MXPA97002286A - Expandable material of multip layers - Google Patents

Abstract

The present invention relates to a thermosettable, latent melt flowable sheet or laminate material, characterized in that it has an upper surface and a lower surface, comprising two or more layers, comprising an upper layer and a lower layer, the layer The lower layer comprises a melt-flowable, thermosetting, latent composition and the lower layer comprises a melt-flowable, thermosettable, expandable, latent composition wherein, by applying the sheet material to a substrate by contacting the lower layer with the same layer. and heating the lower flowing and expanding layer and the upper flowing layer, and wherein one of the upper or lower layers comprises a copolymerizable macromonomer of the formula: (II) X- (Y) n Z wherein X is a group vinyl copolymerizable with an alkyl acrylate and reinforcing monomers, and is a divalent linking group where n can be zero or one, and Z is a monovalent polymeric portion; that has a Tg greater than 20

Description

OF LAYERS Tp.TTPT.gg the invention This invention relates to a melt flow sheet material and to a method for using same.

Antec «adßn '_. ßs gives the invention U.S. Patent No. 5,086,088 discloses a thermosetting, latent pressure sensitive adhesive composition comprised of an acrylate pressure sensitive adhesive and an epoxy resin component which is provided for the curing of the thermoset. The adhesive composition is described as an end for clamping molded into the roof of a carriage body.

BrflfY »Riffmffln n the Pr-tumtß tt_Y M. n, The present invention provides a melt-curing, thermosetting, latent sheet material having a top surface and a bottom surface comprising two or more layers. The sheet material comprises a REF: 24393 top layer and a bottom layer the top layer comprises a melt-flowable, thermosetting, latent composition, and the bottom layer comprises a meltable, thermosettable, expandable, latent flowable composition in which, by applying the sheet material to a substrate by contacting the bottom layer therewith and heating it to an elevated temperature, the bottom layer flows and expands and the top layer flows. Preferably: the upper layer flows laterally so that the lower layer is essentially encapsulated by the substrate in the upper layer. The melt-curing, thermosetting, latent sheet material of the invention provides particular utility for providing topographic and / or protective features to primed or unprimed metal automotive parts or to follow-up bodies formed by such metal parts. The fluidity and expandability of the lower layer provides the optimum sealing of such joints. The fluidity of the upper layer provides an aesthetically pleasing surface which can be, for example, painted.

Brief Description of the Drawings The invention will now be described in greater detail with reference to the accompanying drawings, in which: Figure 1 is an end view of a sheet material of the invention prior to the thermosetting or curing placed e > n the channel in the awning of a car; Figure 2 is an end view of the sheet material shown in Figure 1 subsequent to the thermosetting or curing, - Figure 3 is an end view of the sheet material of the invention prior to the thermosetting or curing placed in the channel of a car's awning; and Figure 4 is an end view of the sheet material shown in Figure 1, subsequent to thermosetting or curing.

Detailed Description of the Invention The melt-curing, thermosetting, latent sheet material of the present invention comprises at least two layers of latent thermosetting, melt-flowing compositions (ie, the "top layer" and the "bottom layer"). By "melt flowable" it is meant that, upon heating, the composition shows a viscous flow resulting in an irreversible volume deformation of the composition. The preferred fused melt composition for the lower layer also shows properties of pressure sensitive adhesive. The melt flowable composition for the top layer can also show, if desired, pressure sensitive adhesive properties. By "pressure sensitive adhesive" it is meant that the sheet material exhibits pressure sensitive adhesive properties by its application or curing temperature at which the sheet material is exposed. Generally, the temperature will be between room temperature and about 204 ° C. It is currently preferred that the adhesive exhibit pressure sensitivity properties at room temperature, for example at 22 ° C. With reference to the drawings, in figure 1 there is shown a sheet material 10 consisting of an upper layer 12, a lower layer 14 and a polymeric film 16 between them. The sheet material 10 is placed and adhered to the channel 18 in the awning which is formed by joining the panels 20 and 22. After thermosetting by heating to an elevated temperature, the lower layer 14 expands: and the upper layer 12 it flows so that the lower layer 14 is essentially encapsulated by the upper layer 12 and the channel 18 of the awning, as shown in Figure 2. With reference to the drawings, in Figure 3 there is shown a sheet material 20 consisting of an upper layer 22 and a lower layer 24. The sheet material 20 is suitable and adheres to the channel 28 of the awning which is formed by the joined jacks 30 and 32. After thermosetting by heating to an elevated temperature, the lower layer 24 has expanded and the upper layer 22 has become fluid. In this case, the lower layer 24 is essentially not encapsulated by the upper layer 22 and the channel 28 in the awning, as shown in Fig. 4. The melt flow compositions, thermosetting, used both in the upper layer and in the upper layer. The lower layer preferably comprises photochemical reaction products of starting materials comprising (i) a prepolymeric (i.e., partially polymerized to a viscous syrup usually between about 100 to 10,000 centipoise) or monomeric syrup consisting of an acrylic acid ester or methacrylic; (ii) an epoxy resin; (iii) a photoinitiator, - and (iv) a heat activatable hardener for the epoxy resin. The composition used to prepare the top layer also preferably includes an acrylate copolymer, as will be discussed in the following.

The composition used to prepare the lower layer, which is capable of expanding by heating, additionally includes a blowing or foaming agent, or "3S" expandable spheres. All such compositions can be coated and conveniently polymerized in a variety of thicknesses including relatively thick sections. The photopolymerizable prepolymer or monomeric syrup used in the composition for preparing both the top layer and the bottom layer contains an acrylic or methacrylic ester and optionally a copolymerizable reinforcing comonomer. The acrylic or methacrylic ester is a monofunctional acrylic or methacrylic ester of a non-tertiary alcohol, having from about 4 to about 12 carbon atoms, in the alcohol moiety. Included within this class of esters are n-butyl acrylate, hexyl acrylate, 2-ethylhexyl ether, octyl acrylate, isooctyl acrylate, decyl acrylate and dodecyl acrylate. You can use mixtures of esters. If used, the copolymerizable reinforcing monomer is preferably selected from the group consisting of monomers such as isobornyl acrylate, N-vinylpyrrolidone, N-vinylcaprolactam, N-vinylpiperidine, N, N-dimethylacrylamide and acrylonitrile. Preferred reinforcing monomers are nitrogen-containing monomers such as those nitrogen-containing monomers listed above. The reinforcing monomer is generally selected such that a homopolymer prepared therefrom will have a greater vitreous transition than a homopolymer prepared from the acrylic or methacrylic ester used. Small amounts of copolymerizable acids such as acrylic acid may be included insofar as they do not detrimentally affect the curing of the epoxy resin. Acrylic acid can be used in amounts of up to about 2 parts of acrylic acid to 100 parts of acrylic ester monomer. In the case where the prepolymer or monomeric syrup comprises acrylic or methacrylic ester and a reinforcing comonomer, the acrylic or methacrylic ester will generally be present in an amount of about 50 to 95 parts by weight, and the reinforcing comonomer will be present in a corresponding amount of about 50 to 5 parts by weight. A person ordinarily skilled in the art will be able to vary the nature and amount of the reinforcing monomer to obtain the desired properties. In addition, both the photopolymerizable acrylic or methacrylic prepolymer or the monomeric syrup and the copolymerized polymer form a stable mixture with the epoxy resin.

As indicated above, the composition used to prepare the top layer preferably includes a copolymer of acrylate which contributes to handling properties prior to heat setting and the hardness of that layer when fully cured while, at At the same time, it does not affect or damage its ability to flow: from the layer to the heating to carry out the curing. Preferably, the acrylate copolymer has a Tg greater than 22 ° C. Suitable acrylate copolymers include isobutyl methacrylate polymer, polyethylene methacrylate copolymer, methyl methacrylate copolymer, and the two copolymers of methyl methacrylate / butyl methacrylate sold by Rohm & Haas under the trade names Acryloid ^ B-d? , B-72, B-82, B-60, and B-56, respectively. The amount of any acrylate copolymer preferably used will be from about 5 to 100 parts by weight per 100 parts by weight of the prepolymer or monomeric syrup. The acrylate copolymer can also be added to the lower layer. Polyacetal polymers can also be added to the compositions of the top layer or the bottom layer to increase the modulus of the cured composition before the thermosetting, as well as to improve the addition of paint a. the sheet. A preferred type of polyacetal polymer is poly (vinyl butyral). The poly (vinyl butyral) must yield sufficient hydroxyl functionality to be soluble in acrylate monomers. Hydroxyl functionalities between approximately 9% and 13% have proven useful. Poly (vinyl butyral) / is usually used in amounts of about 10 to 120 parts per 100 parts of acrylate, and preferably are used in amounts of about • 20 to 80 parts per 100 parts of acrylate. The addition of larger amounts of poly (vinylbutyral) can be used to reduce or eliminate stickiness of the sheet material so that the sheet material becomes easier to handle. Poly (vinyl butyral) resins are sold by Monsanto by the trademark BUTVAR "to various degrees having different molecular weights, etc. Other useful additives to modify the flow properties and to improve the handling properties of the sheets include polymers of polyester, which can be added to the top or bottom layer.Polymeiros are usually added to the top layer.The amount of polyester polymer that can be used is limited by the amount of polymer that is soluble in the acrylate monomer or syrup It has been found that amounts of up to about 20 parts of polyester polymer per 100 parts of acrylate monomer are useful The preferred polyester polymers are those having carboxyl or hydroxyl end groups, and an average number of molecular weight between about 7500 and 200,000, more preferably between approximately 10,000 and 50,000, and of handling to more preferable between approximately 15,000 and 30,000. It is preferred that the polyesters are also linear, saturated and semi-crystalline. Suitable polyesters are commercially available from Hüls America, Inc. under the trademark Dynapol with the following product numbers S1402, S1358, S1227, S1229, S1359 and S1401. Another useful class of polyesters are polycapclactones which can be added to any layer. These are particularly useful in the upper layer to improve the flow properties and improve adhesion of the sheet to the sheet. The polycaprolactones can be used in the same amounts as the polyester polymers. Useful polycaprolactones include those described in U.S. Patent No. 3,169,945. The preferred polycaprolactone polyols can be represented by the following structure: HO- [(CH 2) 5-C (= 0) -0) n R- [-0-C- (= 0) - (CH 2) 5] n-OH wherein R is a divalent alkylene radical, and n is approximately 2 to 200. Polycaprolactone diols and useful polymers are commercially available from Union Carbide Inc under the trademark TONE. It may be desirable to use glycidyl methacrylate, glycidyl acrylate or other epoxy functional monomer together with the acrylic or methacrylic ester and a reinforcing monomer, if used. Such epoxy-functional monomers, if used, will preferably be present in an amount of about 0.1 to about 10 parts per 100 parts by weight of all monomers used. Another functional epoxy oligomer useful as reflectance or crosslinking species is the epoxy adduct of 2-isocyanotoethyl methacrylate and glycidyl ether of bisphenol?. If used, the adduct can be used in amounts of up to about 100 parts of adduct per 100 parts of acrylate and preferably from 1 part to parts per 100 parts of acrylate. The reinforcement of the cured composition can also be carried out by the use of silane which have an organofunctional group capable of reacting with an epoxy group or a vinyl group, and a silane functional group which can react with silanol groups on the surface of suitable inorganic fillers. If used, the silanes can be used in amounts of from about 0.01 parts to about 10 parts per 100 parts of acrylate, and preferably from about 0.1 parts to about 5 parts. Silanes are commercially available from various suppliers, including Hüls America, Inc. Mixtures of silanes can also be used. In a useful embodiment, a mixture of two silanes having different functional groups can be used. For example, a first silane may contain a functional group that is selectively reactive with epoxy groups, and a second silane that is reactive with acrylates. Thus, a silica-containing filler material can serve as a bridging agent for connecting the epoxy and acrylate phases of the thermosetting pressure sensitive adhesive. Commercially available silanes that can function in this manner are Hüls G6720 (epoxy silane) and Hüls M8550 (methacrylate silane), both available from Hüls America Inc. A weight ratio l -.l is useful, although the amount of each silane is can st for the ratio of the acrylate portion to the epoxy portion. Crosslinking agents for only the acrylate phase can be added to increase the stiffness of the sheet material and facilitate handling. Useful crosslinking agents are those which are polymerizable by free radicals with acrylate monomers such as divinyl ethers and multifunctional acrylates. Examples of multifunctional acrylates include 1,6-hexanediol diacrylate, tri-methylolpropane triacrylate, pentaerythritol tetraacrylate and 1,2-ethylene glycol diacrylate. The acrylate crosslinking agent should not impede the flow and / or expansion of any of the upper or lower layers. Amounts of up to about 1 part per 100 parts of acrylate can be used, and 0.1 to 0.2 parts are preferred. The rigidity of the tapes can also be increased by the addition of at least one copolymerizable macromonophore to the compositions for the environmentally resistant layer, the expandable layer, or both. The useful copolymerizable monomer is a polymeric moiety having a vinyl group which will copolymerize with the alkyl (meth) acrylate monomer, and if included, the reinforcing monomer (e.g., isoborinyl acrylate). The macromiDnomer is represented by the general formula (I) X- (Y) n-Z wherein X is a vinyl group copolymerizable with the alkyl acrylate and reinforcing monomers; Y is- a divalent linking group in which n may be zero or one, and Z is a monovalent polymer portion having a Tg greater than 20 ° C and a molecular weight in the range of about 2,000 to 30,000 and which is essentially not reagent under copolymerization conditions. The preferred macromonorrero is defined additionally by presenting a group X with the general formula II) R R - H where R is a hydrogen atom or a group COOH and R 'is a hydrogen atom or a methyl group. The double bond between the carbon atoms provides a capping portion of copolymerizing with the alkyl acrylate and the reinforcing monomers. The preferred macromonomer includes a group Z which has; the formula wherein R 2 is a hydrogen atom or a lower alkyl group, R 3 is a lower alkyl group, n is an integer from 20 to 500 and R 4 is a monovalent radical that is selected from the group consisting of wherein R5 is a hydrogen atom or a lower alkyl group and -C02R6 wherein R6 is a lower alkyl group. Preferably, the macromonomer has the general formula that is selected from the group consisting of: O H (VI 'or X-C-O-CH2CH2-NH-C -O-C-CH2-. K : vn: R X-CH2-O 5 -CC-CCHH22-Z. H ÍVIII) or H (IX) X -O-C- -CCHH22--0O-C-CH2- k wherein R7 is a hydrogen atom or a lower alkyl group.

Polymeric vinyl terminated macromonomers are known and can be prepared by the method described in U.S. Patent Nos. 3,786,116 and 3,842.0E > 9 (Milkovich, et al). Macromonomers are also commercially available, eg, from styrene macromonomer RC13K from Sartomer. The amount of macromonomer that is useful ranges from about -2% to about 20% by weight of the acrylate composition of the base consisting of an acrylate monomer, the reinforcing monomer and the macromonomer. Larger amounts of macromonomer can be used but the cost would be prohibitive. Preferably, the amount of macromonomer is 3-15% and more preferably, about 4-12%. In order to provide a sheet material that exhibits the desired flow characteristics in response to heating, it may be desirable to include a chain transfer agent in the starting materials used to prepare the thermosetting pressure sensitive adhesive. Such inclusion facilitates a low molecular weight crical polymer. Chain transfer agents are generally known and include halogenated hydrocarbons such as carbon tetrabromide and sulfur compounds such as lauryl mercaptan, butyl mercaptan, ethanethiol and 2-mercaptoether. The chain transfer agents can also be polymeric or oligomeric in nature such as the polymers and macromonomers described in U.S. Patent Nos. 4,746,713, 5,028,677, 5,264,530 and 5,290,633. In particular, the macrommonomers described in U.S. Patent No. 5,264,530 incorporated herein by reference. reference, they are useful. Commercially available macromonomers that can function as a chain transfer agent include those sold under the trademark ElvaciteKR by ICI. The compositions may additionally include acrylic resins which have been found to improve the flow properties. Such acrylic resins are commercially available, for example, under the tradename of acrylic resin ISOCRYL EP-550 (Estron Chemical, Inc.) and acrylic resin SCX 8008 (Johnson ax Specialty Chemical). The epoxy resins useful for both the upper layer and the lower layer can be selected from the group of compounds containing an average of more than one, and preferably at least two epoxy groups per molecule. Preferably, the epoxy resin is liquid or semi-liquid at room temperature. The most preferred epoxy resins for the top layer are liquid at room temperature to provide the desired level of flowability. layer higher than the heating during the curing process. Representative examples of suitable epoxy substances for both the lower layer and the upper layer include phenolic epoxy resins, epoxy benol resins, hydrogenated epoxy resins, aliphatic epoxy resins, halogenated bisphenol epoxy resins and novolac epoxies. It is also possible to use mixtures of epoxy resins. Preferred epoxy resins for the lower layer include bisphenol epoxy with the most preferred epoxy resin being the diglycidyl ether of bisphenol-A, formed by reaction of bisphenol-A with epichlorohydrin. Examples of preferred liquid epoxy resins for the top layer include hydrogenated epoxy resins and aliphatic epoxy resins. The epoxy resin used in each composition is generally present in an amount from about 25 to 150 parts by weight, based on 100 parts, er. weight of the prepolymer or monomeric syrup contained in the composition used to make each respective layer. The photoinitiator used to polymerize the prepolymer or monomeric syrup in each composition can be any conventional free radical photoinitiator activated by, for example, ultraviolet light. An example of a suitable photoinitiator is 2,2-dimethoxy-1,2-diphenylethin-1-one (Irgacure ™ dBl available from Ciba-Geigy Corporation). The photoinitiator will usually be used in an amount of about 0.01 to 5 parts by weight per 100 parts of the prepolymer or monomeric syrup. A heat activatable hardener is added to each composition to carry out the curing of the epoxy resin under application of heat. The hardener may be of any type, but preferably an amine type hardener which is selected from the group comprising dicyandiamide or polyamine salts. These are available from various sources, for example, 0micure ™ available from Omicron Chemical and Ajicurem available from Ajinomoto Chemical. The heat-activatable hardener will usually be used in an amount of about 0.1 to 20 parts by weight, and preferably 0.5 to 10 parts by weight per 100 parts by weight of the prepolymer or monomeric syrup. Sufficient hardener must be used to obtain the curing of the epoxy resin. The polymerizing agents for epoxy resins can be varied for each layer in order to impart different! Curing temperatures for each layer, and this will control the flow characteristics of each layer. Other types of polymerizing agents for resins that are useful include polymerizing agents for acid and anhydride resins. For example, by using an amine salt as a polymerizing agent for resins in the expandable layer and a polymerizing agent for anhydride resins in the upper or environmentally resistant layer, a tape, a two-layer sealant can be manufactured in which the expandable layer flows and expands and is cured at a certain temperature, and at the same time the environmentally resistant layer Eluyes and cures at a higher temperature. Examples of polymerizing agents for anhydride resins include phthalic anhydride, hexahydrophthalic anhydride, tetrahydrophthalic anhydride, trimellitic anhydride, pyromellitic dianhydride, maleic anhydride, 1,2-cyclohexane dicarboxylic anhydride, succinic anhydride, dodecyl succinic anhydride, 3, 3 ', 4 dianhydride, 4'-benzophenotetra-carboxylic acid, methyl nadic anhydride, methylhexahydrophthalic anhydride, polymeric anhydrides and glutaric anhydride Examples of polymerizing agents for acid resins include acrylic acid, methacrylic acid, crotonic acid, intaconic acid, fumaric acid, maleic acid, citraconic acid, adipic acid, suberic acid, azelaic acid, sebacic acid and dodecanedioic acid. Because there are many points, for example, in a cycle of automotive paint in which a sheet material can be used, the heating to which the sheet material is exposed may be insufficient to fully cure the epoxy resin. In these cases, it may be advantageous to add an accelerator to the prepolymer mixture so that the resin can cure completely at a lower temperature, or can heal completely when exposed to heat for shorter periods. Accelerators are typically selected based on the type of polymerizing agent for epoxy resins used. Imidazoles and urea derivatives are particularly preferred in the practice of the present invention for use as accelerators due to their ability, as shown in the examples with amine curing agents herein, to extend the shelf life of materials based in acrylic containing uncured epoxy resin. The most preferred imidazoles for use in the present invention are 2,4-diamino-6- (2'-methylimidazolyl) -ethyl-s-triazine isocyanurate, 2-phenyl-4-benzyl-5-hydroxymethylimidazole, 2, 4-diamino-6 - (2 '-methylimidazoyl) -ethyl-s-triazine, hexakis phthalate (imidazole) nickel and bis-dimethylurea of toledo. Such an accelerator can typically be used in an amount of up to about 20 parts by weight per 100 parts by weight of the prepolymer or monomeric syrup. For acid and anhydride curing agents, typical accelerators include amines, ammonium compounds, phosphonium compounds, dicyandiamide, and sulfonat compounds. Examples of suitable accelerators for polymerizing agents for acid and anhydride resins are trimethylamine, triethylamine, imidazole, triisoprcpilamine, dimethylbenzylamine, tris- (2,4,6-di ethylaminomethyl) phenol, triethylammonium chloride, triisopropylammonium chloride, dimethylbenzylammonium, triethylamine sulfonate, tetramethylammonium chloride, tetraethylammonium bromide, tetrabutylammonium iodide, triphenylphosphonium acetate, ethyltriphenyl-phosphonium bromide, 2-dimethylaminoethyltriphenylphosphonium bromide, N, N-dimethylacrylamide and N-vinylcaprolactam. As indicated above, the composition used to prepare the lower layer also includes a blowing or foaming agent or expandable spheres which are activated by heating to provide the desired expansion of the lower layer. Suitable blowing or foaming agents are well known in the art and include azo derivatives and inorganic compounds such as carbonates and bicarbonates. Suitable expandable spheres are also well known in the art. A blowing or foaming agent will preferably be used in an amount of about 0.1 to 5 parts by weight per 100 parts by weight of the prepolymer or monomeric syrup in the composition used to prepare the lower layer. Non-woven or loosely woven fabrics or gauze may be used to add strength to the sheet either between the two layers or they may be laminated or one or both surfaces exposed. A nonwoven laminate to the bottom surface also provides channels to allow trapped air to escape during the bonding process. When a strip of the sheet material is applied to a substrate, air may be trapped between the sheet and the substrate, particularly when the bottom surface of the sheet material is tacky. As the sheet material is heated, trapped air expands to form a bubble of air, which collapses when the sheet material cools and a concavity or defect is formed on the surface of the sheet material . The defect can be avoided by laminating a non-woven gauze to the bottom surface so that when it melts enough it flows through the non-woven part and attaches to the substrate, and trapped air can escape around the non-woven fibers.

Useful nonwoven materials can be formed from (ie, natural and synthetic polymer fibers that adhere to the sheet material such as a polyester, nylon, cotton, polypropylene, cellulose acetate, acetate or mixtures thereof. non-woven fabrics are relatively thin, for example, from about 0.005 to about 0.1 mm thick.The useful thickness of the gauze materials can vary based on the thickness of the sheet material, but the gauze is usually less than about 20% of the thickness total of the sheet, and preferably the gauze is less than about 10% of the total thickness of the sheet The suitable nonwoven materials usually have a base weight range of about 5 to about 200 grams / square meter , and preferably * from about 25 to 150 grams / square meter Suitable nonwoven materials are commercially available under the trade name CEREXMR from Mitsubishi Petrochemical Co., and under the trade name Syntex * ® from Reemay Co. Long strands of thread, filament.! can also be used to reinforce the sheet material. The strands can be placed between the layers, embedded within the top or bottom layer, or they can adhere to the exposed surface of both layers. The preferred fibers have a diameter greater than 5 micrometers and less than one tenth of thickness with respect to the sheet material. The threads can be made of polyester, nylon, acetate, cellulose, cotton and the like. The number of strands varies based on the 1: size of the strand, filament and the amount of reinforcement needed. The amount can vary from about 1 to 2,000 strands per centimeter in width, and more typically from about 1 to 200 strands per centimeter in width. A thermoplastic film that is dimensionally stable to. temperatures of use, that is, of signs of painting in an oven of up to 200 ° C and cold ambient temperatures of less than about -40 ° C can be laminated to the exposed surface of the upper layer of the sheet material before the thermosetting to Provide a regular surface for painting after thermosetting. Useful films include polyimide films and biaxially oriented polyester films having thicknesses ranging from about 0.025 mm to about 0.5 mm, and preferably having thicknesses in the range from 0.05 mm to about 0.25 mm. The film can be treated to improve adhesion to the layers, for example, primed or corona treated.

Other useful materials which can be blended into melt-flowable, thermosetting compositions include, but are not limited to, filler materials, pigments, fibers, woven and non-woven fabrics, antioxidants, stabilizers, flame retardants and viscosity adjusting agents. . The above composition is coated on a flexible carrier network, preferably a silicone release coating which is transparent to ultraviolet radiation and polymerized in an inert, ie, substantially oxygen-free, atmosphere, for example, a nitrogen atmosphere. A sufficiently inert atmosphere can be obtained by coating a layer of the photoactive coating with a plastic film which is substantially transparent to ultraviolet radiation and irradiating it through the film in air, as described in U.S. Patent No. 4,181,752 (Martens et al. .). The filling materials can then be removed when it is desired to use the resulting sheet material in the method of the invention. The non-woven materials or strands of yarn, fibers or filaments can be incorporated into the sheet material by coating the composition of both the upper layer and the lower layer on the non-woven material or strands placed on the transparent film., and polymerize the composition. Alternatively, the nonwoven material or the strands can be laminated between the upper or lower layers, or they can be laminated to the exposed surface in both layers. Preferably, the strands or the non-woven part are laminated to the exposed surface of the lower layer. In addition, a film can be placed between the upper layer and the lower layer to improve the handling of the sheet material and to distribute the expansion force as the lower layer expands to improve the aesthetics of the cured sheet material. A polymer film is preferred. The film can also be attached to the exposed surface of the lower layer. Useful films include those made of polyester, acrylates, polyamides, polyimides, polyesters and nylon. Thin metal sheets, such as thin aluminum sheets such as thin sheets of aluminum and nonwoven materials such as nonwoven polyester can also be used for this purpose. When the surface of the lower layer is not sensitive to pressure at the application temperature, for example sticky at room temperature, a pressure sensitive adhesive or a pressure sensitive adhesive transfer tape can be applied as part of , or to the entire surface of the lower layer. Commercially available pressure sensitive adhesive transfer webs include tapes 467 and 468 from the Minnesota Mining and Manufacturing Company. Preferably, the upper layer encapsulates the lower layer and the substrate after heating, but embodiments in which the lower layer is not encapsulated are also useful. The use of a non-encapsulated bottom layer is facilitated by the application of paint to the sheet material. The paint becomes more rigid to the sheet material so that these less preferred embodiments of the invention become more durable. The sheet material may also comprise more than two layers which comprise melt flowable compositions. They can be considered three-layer constructions in which the layers are arranged in different orders. For example, a non-expandable layer / an expandable layer / a non-expandable layer (upper / middle / lower) and non-expandable layer / non-expandable layer / expandable layer constructions, among others, function the same as two-layer constructions. The sheet materials of the present invention have various applications in the industry. One use is in the automotive industry where they can be used in a process to seal metal joints in automobiles. By this process, first a sheet material is prepared for example by the processes described in the following. Subsequently, the sheet material is applied on the joint to be sealed. In a preferred embodiment, a complete seal and joint is obtained because the lower layer of the sheet material flows and expanded, and the upper layer flows to encapsulate the lower layer before hardening. As a result of this expansion and flow, an aesthetic surface appearance is obtained. The exposed surface of the hardened sheet material can be painted or decorated in some other way to match the body of the automobile. In some cases it is desirable that the upper layer has a higher initiation temperature than the lower layer. The initiation temperature is defined as the temperature at which the epoxy material begins to cure, and is determined using a differential scanning calorimeter (Perkin-Elmer DSC-2C) using a velocity gradient of 10 ° C per minute. When the lower layer heals first, the upper layer remains fluid enough to flow over and cover the lower layer. The invention is further illustrated by the following non-limiting examples in which all parts are expressed as parts by weight, unless otherwise indicated.

TESTS PRACTICE CAPACITY A piece of tape that measures 2.5 cm is adhered 2. 5 cm to a 5.0 cm by 10.2 cm panel ED-11 (primed steel panel for electrodeposition available from Advanced Coating Technologies, Inc.). The panel is cured at 177 ° C for 12 minutes. The tape and panel are coated with a base coat (HWB90394 glossy white from PPG Ind., Inc.) and dried at room temperature for about one hour. It is then applied as a clear coat (NCT II of PPG Ind., Inc.) on the base coat and the panel is placed in an oven at 121 ° C for 30 minutes. The painted tape is verified to determine roughness of the painting surface and is classified as OK (without corrugations) or FAIL (with corrugations).

PROOF OF RESISTANCE TO THE ENVIRONMENT This test measures the change in color of the paint due to exposure or "subjection to the environment" in a particular environment. Two panels are prepared for each sample according to the procedure described for PAINTING CAPACITY (painted in white). Then a sample is subjected to aging in a chamber that simulates environmental conditions ("QUV" of Q-Panel Co.) For 250 hours according to ASTM G-53, with repeated cycles of 4 hours of ultraviolet light at 60 ° C followed by 4 hours of condensation humidity at 50 ° C. The other panel prepared in a similar manner is maintained at room temperature in the dark. After 250 hours, exposed and unexposed panels are measured to determine color values using an ACS Spectro-Sensor II spectrophotometer and an associated computer (from Applied Color Systems, Inc.).

The total color difference is calculated on the computer and registered as Delta E under environmental conditions (TH) Low values of Delta E are desired since they indicate less color change.

This test measures the amount of flow the tape shows as it cures. A piece of 2.5 cm by 2.5 cm square tape is placed on the top edge of an anodized aluminum panel of 5.0 cm by 10.2 cm. Weigh a 2.5 cm by 5.0 cm ribbon of anodized aluminum (Wt) and then press lightly on the tape. The panel is held vertically in a panel at 177 ° C for 12 minutes. The panel is removed from the oven and the amount of flow is measured by how far the strip has moved down from the top of the panel. The distance is recorded in centimeters (cm). A distance of 11+ indicates that the strip has moved completely out of the panel.

SCRAP 1PQR SUPERPOSITION A 1.25 cm by 2.5 cm ribbon is adhered between the superimposed ends of two ED-11 panels measuring 2.5 cm by 5 cm so that the free ends of the panels extend in opposite directions and the length of the tape is placed at through the lengths of the panels. The sample is rolled down with two passes of a 6.8 kg roller. For initial results (INIT) the sample is conditioned at room temperature for 20 minutes. Then the opposite ends of the panels are clamped in opposite jaws of an Instron Tensile Tester (tension tester) and pulled at a speed of 5 cm / min. The adhesive failure force is recorded in Newtons / square centimeter (N / cm2) or in MegaPascals (MPa).

For resistance to tearing after curing (CURED) the sample is heated at 177 ° C for 12 minutes, maintained at room temperature for 5 minutes, heated at 121 ° C for 30 minutes and cooled to room temperature before of the test as described in the above.

ADHESION OF DETACHMENT TO 9Q ° A 1.25 cm by 15.2 cm tape is laminated on a 0.13 mm thick strip of anodized aluminum. The strip is then laminated to an ED-11 panel as described above and rolled with 2 passes of a 2-kg roller. The panel is then attached to an Instron device so that the aluminum foil is pulled out at a 90 ° angle. The aluminum foil is pulled at a speed of 30.48 cm per minute. Adhesion to detachment is recorded in Newtons per decimeter (N / dm).

RESISTANCE TO TRACTION AND ELONGATION The tape is cured at 120 ° C for 30 minutes and cooled to room temperature. A specimen in the form of a dumbbell or specimen (prepared in accordance with ASTM 0-412) is held and clamped in the jaws of an Instron Tensile Tester. The jaws are separated at a speed of 50.8 cm per minute. The tensile force (TENS) at break in Newtons / square centimeter (N / cm2) and the elongation (ELON) in% break are recorded. For tests C, D, E and F in tables 5 and 6, the sheet is cured for 20 minutes at 177 ° C. The tensile strength and elongation is determined according to ASTM D412-87 in an Instron ™ Tensile Tester using the described sample length of 33.27 mm, and a jaw separation speed of 50.8 centimeters per minute. The samples are conditioned for at least 24 hours after curing before the test. The stress results are reported in MegaPascals (MPa) and the elongation is reported in percent of the original length (%).

EXPANSION The thickness of the tape is measured before heat curing and after curing by heat and expansion. The difference in thickness is recorded in millimeters (mm).

STORAGE MODULE This test measures the module of a tape. The test is performed on a sample that is 25 mm in diameter and 1.5 to 2.0 mm thick. The sample is carried out in a Rheometrics Dynamic Analyzer II available from Rheometrics, Inc., using a parallel plate geometry at 25 ° C and a frequency of 10 radians per second. The storage module (G1) is recorded in dynes / cm2.

Paint Adhesion: A measured sample of approximately 2.54 cm by 7.5 cm is applied to a PPG ED-11 electro-coated steel panel and heated at 177 ° C for 12 minutes. 1.1 panel is then coated with a basecoat H B90394 (white PPG Industries, Inc.) and subjected to .norneado in an oven at 121 ° C for 30 minutes. A two-part clearcoat is manually mixed (part A is CNCT2AH, part B is CNCT2BE, from PPG Industrie;, Inc.), according to the manufacturer's instructions and spray-painted on the basecoat and cured at 177 ° C for 12 minutes. The painted panel is then cooled to room temperature and conditioned for at least 16 hours. The paint is then tested to determine the adhesion of paint by cross-scraping the cured paint surface and testing to determine the adhesion of the paint to the sheet. The test is carried out in accordance with ASTM D-3359-90. The results:, of the test are reported as a percentage of the paint surface that remains intact on the sheet.

Curing Hardness: The hardness of a cured sample is determined for 20 minutes at 177 ° C using a Shore A hardness meter and the results of the test are reported in Shore A hardness.

BA - butyl acrylate B60 - butyl methacrylate / butyl methacrylate copolymer with Tg = 75 ° C (Acryloid "* B-60 available from Rhom and Haas Co.) B66 - n-butyl methacrylate / methyl methacrylate copolymer with Tg = 50 ° C (Acryloid1 B-66 available from Rhom and Haas Co.) B67 - isobutyl methacrylate polymer with Tg = 50 ° C (Acryloid ^ B-67 available from Rhom and Haas Co.) B72 - copolymer of ethyl methacrylate with Tg = 40 ° C (Acryloid "11 B-72 available from Rhom and Haas Co.) B82 - methyl methacrylate copolymer with Tg = 35 ° C (Acryloid "* B-82 available from Rhom and Haas Co.) CDDGE - 1,4-cyclohexane di-ethanol diglycidyl ether (HeloxyMR107 from Rhone-Poulenc) DGEBA - bisphenol A digiicidyl ether (EponR828 from Shell Chemical Co. ) DGEOBA - diglycidyl ether oligomer of bisphenol A (EPONMR1001F from Shell Chemical Co.). DICY - micronized dicyandiamide (DYHARDMR 100 available from SK Chemical) HDGEBA - hydrogenated diglycidyl ether of bisphenol A (EponexMR1510 from Shell Chemical Co.) HINP - Hexakis imidazole phthalate nickel IRGACURE ^ - 2, 2-dimethoxy-2-phenylacetophenone otoinitiator (available from Ciba-Geigy) KB-1 - benzyldimethyl ketal photoinitiator (Esccure ^ KB-l from Sartomer) NVC-N-vinylcaprolactam TDI-1, 1 '- (4-methyl-m-phenylene) -bis (3,3' -di-ethylurea (OmicureMR24 from Omicron Chemicals) NNDMA-N, N-dimethylacrylamide (Jarchem) ToneMR0240 - Diol polycaprolactone (Union Carbide; PF = 2000) ToneMRP767E - Polycaprolactone polymer (Union Carbide) DynapolMRS1402 - Polyester copolymer (Hülls, America) Irg 1010 - Irganox antioxidant ^ lOlO (Ciba-Geigy) 2MZ Azine - CurezolMR2MZ Azine - 2,4-diamino-6 - [2'-methylimidazolyl- (1 ')] ethyl-s-triazine (Air Products) C15-250 - glass microspheres (Minnesota Mining &Manufacturing Co.) CBR4 - carbon tetrabromide HDDA - hexane dioldiacrylate DICY - AmicureMRCG-l200 dicyandiamide micronized (Air Products) VAZO ^ dd - 1, 1 '-azobis (cyclohexanecarbonitrile (DuPont) PMMA - Poly (methyl methacrylate) macromer (ICI) Examples 1-14 Tapes are prepared as described in the following using the specific amounts of the materials in each of the formulations as shown in Table 1. A 50/50 mixture of BA and NVC is heated to about 50 ° C to form a solution. More BA is added so that the total amount of BA is equal to the amount shown in the table. The solution is placed in a container with HDGEBA and B60. The container is placed in a roller mill overnight to dissolve the B60. After B60 is dissolved, the following materials are added: photoinitiator - 0.14 pha (parts per hundred parts of BA and NVC combined) Irgacure ^ edl: epoxy curing agents - 7.5 phr (parts per hundred parts of epoxy resin) DICY and 6.2 phr of TDI; and 4 parts of hydrophilic smoked silica (Aerosil 200 available from DeGussa). The composition is mixed on a high shear stirrer for about 15 minutes, degassed and applied as a knife coating to a thickness of about 1.1 mm on a 0.05 mm thick silicone coated polyester coating and covered with a coating Similary. The coated composition is subjected to photopolymerization to form a sheet using ultraviolet light sources having 90% emissions between 300 and 400 nm with a maximum at 351. The intensity of the light is 1.54 mW / cm2 above the wave and of 1.5: mW / cm2 below the wave, measured with a UVIRAD radiometer (Model No. VR365CH3) of E.IT (Electronic Instrumentation &Technology, Inc.). The total energy is 397 mJ / cm 'above the network and 386 mJ / cm2 below the network. The sheet is then cut into strips and tested for peel strength, tensile strength and tensile strength tests. elongation, resistance to detachment by superposition, wear to the environment and melt flow, according to the previous test procedures. The test results are shown in Table 1. All the samples presented an OK rating with respect to painting capacity.

I The data in Table 1 show that these tapes have adequate tensile strength, good tear properties by superposition and good melt flow before curing to a thermoset state.

Examples 15-23 Ribbons were manufactured as described in Example 1 with the compositions shown in Table 2, except for the following changes: 0.14 pha of KB-1 is used as the photoinitiator; the epoxy curing agents are 4.5 phr of DICY and 1.0 phr of HINP; and instead of AerosilMR200, it will be used. 5.0 parts of Cab-O-Sil M5 silica from Cabot Corp. Example 19 is prepared with a different epoxy material CDDGE. In Examples 20-23 different copolymers were used as follows: Example 20-B67; Example 21 - B72; Example 22 - B82, Example 23 - B66. The test results are shown in Table 2. The tapes need to qualify as OK for painting ability.

OR * Different epoxy resin was used as described above. + Different polymers were used as described above. The epoxy curing agents used were 6 phr of DICY and 3 phi of HINP.

The data in Table 2 shows that the tapes flow at 177 ° C and cure to provide adequate overlap properties.

Example 24 A three-layered tape having an expandable layer, a flowable c.apa that is also environmentally resistant, and a film between the expandable and flowable layers is constructed. The flowable layer is prepared by mixing 40 parts of BA and 40 parts of NVC and heating to about 50 ° C to form a solution. The solution is placed in a container and 20 parts of BA, 80 parts of B60 and 80 parts of HDGEBA are added to form a mixture. The container is then; Cover and mix in a roller mill overnight to dissolve the B60. To the mixture is added 0.14 parts of KB-1 photoinitiator, 0.10 parts of an antioxidant (IrganoxMR1010 of Ciba-Geigy), 4.5 parts of DICY, 1.0 parts of HINP and 5 parts of Cab-O-Sil M5. After mixing with a high-speed mixer for approximately 15 minutes, the mixture is degassed and applied as a coating to a thickness of approximately 1.5 ml on a silicone-coated polyester release coating material of 0.05 mm. thickness. A 0.025 mm thick polyester film that has both sides primed is placed on top of the coating mix. The primer is an aqueous dispersion of colloidal silica having 0.25 of Nalco 2326 (ex Nalco Chemical Co.), 0.3% of 3-aminoprop: .. ltriethoxysilane, and 0.03% of Triton X-100 (ex Rohm &Haas) an deionized water. The mixture applied as a coating is photopolymerized to form a sheet using ultraviolet light sources that have 90% of the emissions between 300 and 400 nm with a maximum of 351. The intensity of the light is 2.40 mW / cm2 above the network and of 1.50 mW / cm2 below the network measured with a UVIRAD radiometer (model number VR365CH3) from EIT (Electroni.c Instrumentation &Technology, Inc.). The total energy is 401 mJ / cm2 above the network and 251 mJ / cm2 below the network. The tested tape has a tensile strength (INIT) of 89 N / cm2 and an elongation of 840% at room temperature, and a tensile strength (CURED) of 574 N / cm2 and an elongation of 50% after heating as described in the previous test. The expandable layer is prepared by mixing 20 parts of BA with 20 parts of NVC and heating to about 50 ° C to form a solution. The solution is placed in a container: with 60 parts of BA, 80 parts of DGEOBA, and 20 parts of DGEPA. The container is covered and left in a roller mill overnight. The mixture is then added with 0.1 parts of KB-1, 0.8 parts of carbon tetrabromide, 4.5 parts of DICY, 1.0 parts of HINP, 0.60 parts of; 2, 2- '-azobis-2-methylbutyronitrile (Vazo 67 from Du Pont: Company) 0. 1 5 parts of glycidoxioropyltrimethoxysilane (G6720 from Hüls America, Inc.), 8 parts of Aerosil R-972, 2.5 parts of Cab-O-Sil M5 and 4 parts of glass bubbles (glass bubbles C15-250 available from Minnesota Mining and Manufacturing Co.). The mixture is vigorously agitated, then degassed and applied as a knife coating to a thickness of about 0.5 mm on a 0.05 mm thick silicone coated polyester release sizing. A 0.05 mm thick silicone coated polyester release sizing is placed on the coated mixture and the mixture cured as described above for the flowable layer. The light intensity is 2.38 mW / cm2 above the grid and 1.49 mW / cm2 below the network. The total energy is 281 mJ / cm2 above the network and 176 mJ / cm "below the network, a three-layer composite material 2.02 mm thick is used to remove one of the coating materials of releasing the expandable layer and laminating the expandable layer to the other primed surface of the polyester film that adheres to the flowable layer.

A 1.9 cm by 7.6 cm tape is cut from the composite material for testing. The side of the expandable layer of the tape is applied on an ED-11 panel and the other release size on the flowable side is removed. The panel with the tape is heated at 177 ° C for 12 minutes. After cooling and cutting off the tape, the upper fluid layer is found to cover the exposed surfaces of both the polyester film and the lower expandable layer so that all of the exposed surfaces of the tape are resistant to environment. The thickness of the tape increases from 2.02 to 2.5 mm.

Examples 25-30.

A melt-sealing composition for a top layer is prepared, according to the procedure of Example 2, having a composition of 60 parts of BA, 40 parts of NVC, 80 parts of HDGEPA, 80 parts of B60, 0.16 parts of KB-1, 6 parts of DICY, 3 parts of 2MZ Azine (from Air Produts), and 4.5 parts of Cab-O-Sil M5. The composition is applied as a coating between the two polyester sizes treated with release and cured as in Example 24. An expandable composition is prepared for the lower layer, according to the procedure of Example 24, which has a composition of 80 parts. of BA, 20 parts of N, N-dimethylacrylamide, 20 parts of DGEBA, 80 parts of DGEOBA, 20 parts of B60, 0.1 parts of KB-1, 0.4 parts of * - carbon tetrabromide, 0.6 parts of 1,1- azobis (cyclohexane carbonitrile), (Vazo 88), 0.15 parts of glycidoxypropyltrimethoxysilane, 4.5 parts of DICY, 1.0 parts of HINP, 2 parts of Cab-O-Sil M5 and 4 parts of Aerosil E972 (available from DeGussa). The composition is applied as a coating to a thickness of 0.51 mm and cured as described above for the top layer. The reinforcement layers, shown in Table 3, are laminated at room temperature between the two layers for the 26-30 ams. Example 25 does not have a reinforcing film. The reinforcement film of example 30 is prepared by mixing 80 parts of isooctyl acrylate, 20 parts of acrylic acid and 0.04 parts of Irgacure ^ dSl, and polymerizing to a cohesive viscosity of about 3000 cps using ultraviolet black light. The partially polymerized mixture is then applied as a coating to a thickness of; 0.13 mm between the polyester films treated for release, and cured as described above for the upper and lower layers. Samples measuring 2.5 cm by 7.5 cm from each of the sheets are cut and placed on 5 cm by 10 cm steel panels that have been electrocoated with PPG-ED-11 (from Advanced Coatings Technology, Inc.). The leaves are subjected to heat-hardening at 177 ° C for 20 minutes. After cooling, the samples are examined for sealing and appearance. All of the samples exhibit encapsulation and complete sealing of the lower layer by the upper layer. Examples 26-30 have a smooth surface after thermosetting, while Example 25 has a rough surface.

Example 31 A composition of a 1 mm thick expandable layer is repaired by mixing 15 parts of acrylate, 85 parts of N-vini Lpyrrolidone and 0.04 parts of Irgacure ^ dSl in a recipient purged with nitrogen and partially polymerized with ultraviolet black light until a viscosity of approximately 3000 cps. The following was added with continuous agitation: 0.1 parts of Irgacure ™ 651, 85 parts of DGEOBA with an epoxy equivalent weight of 500, 15 parts of DGEBA, 7 parts of dicyandiamide (CG1200 of Omicron Chemical o. ), 2.5 parts of 2,4-diamino-6- (2'-methyl-midazoyl) -ethyl-S-triazine isocyanurate (2MA-OK from Shikoku Chemical: o. Ltd.), 7 parts of silica (AerosilMRR- 972 of DeGussa), 5.5 parts of glass bubbles (C15 / 250 glass bubbles from Minnesota Mining and Manufacturing Co.), 0.4 parts of} polydimethylsiloxane (TSF-451-1000 from Toshiba Silicone Co. Ltd.), 4 parts of foaming agent (Microcap-feule F-50 of Matsumoto), and 0.05 parts of mercaptop :: opionic acid. After mixing, the composition is degassed, applied as a coating to a thickness of 1 mm and cured as described in Example 1 by utilizing a light intensity of 1.76 mW / cm2 at the upper and lower apse, and of 975 mJ / cm2 of total energy to form an expandable layer. The expandable layer has an initiation temperature of 145 ° C (determined by DSC as described above). A melt flowable layer of 1 mm thickness is prepared as described above for an expandable layer, except that DICY, 2MA-0K, and the foaming agent are not used, and 15 parts of acid dihydrazide are added. Adipic to the composition as the polymerizing agent for epoxy resins. The melt-flow layer has an initiation temperature of 175 ° C. A sheet of material is prepared by laminating a melt-flowable layer to the expandable layer with a hand-operated roller to form a 2-mm-thick sheet. A sample is placed on a panel coated with ED, with the expandable layer against the panel, and cured at 150 ° C for 20 minutes. The surface of the cured leaf is regular and free of corrugations.

Examples 32-35 A melt-flowable layer (A) composition is prepared by mixing 72 parts of BA, 28 parts of N, N-dimethylacrylamide (NNDMA) and 0.04 parts of Irgacure ^ dSl. The mixture is partially polymerized as described in Example 30. The following are added to the mixture: 0.1 parts of Irgacut6 ^ 651, 2.0 parts of glycidyl methacrylate, 60 parts of EponMR1001 (from Shell Chemical Co.), 20 parts of DGEBA, 6 parts of CG1200, 2 parts of 2MA-OK, 4 parts of Aerosil R972, 4 parts of C15 / 250 glass bubbles and 0.2 parts of 3-mercaptopropionic acid. The composition is mixed, se; degass, is applied as a coating to a thickness of 1 mm and cured as in Example 31. Layer B is prepared in the same manner as layer A with the following changes in composition: 80 parts of BA, 20 parts of NNDMA, 3 parts of glycidyl methacrylate, 85 parts of Epon ^ 100l, 15 parts of DGEBA, 7 parts of CG1200, 2 parts of 2MA-OK, and 1.2 parts of a blowing agent (AZ-M3 from Ohtsuka Chemical ). Layer C is prepared in the same way as layer B with the following changes in composition: 2.0 parts of 2MA-OK is used and the blowing agent is removed. The sheet materials are prepared by laminating the layers as shown in Table 4 with a manual roller. Samples are laminated on ED-11 coated steel panels and cured at 140 ° C for 20 minutes. The samples are cooled to room temperature before the test shown in Table 4.

Example 36 An expandable layer is prepared by mixing 80 parts of BA, 20 parts of NNDMA, 80 parts of DGEOBA, 20 parts of DGEBA, 5.0 parts of polycaprolactone (ToneMR767E available from Union Carbide), 2.8 parts of DICY, 1.2 parts of HINP, 0.16 parts of KB-1, 0.1 parts of Irganox ^ lOlO, 0.4 parts of CBr4, 0.05 parts of hexanediol diacrylate, 1.0 parts of 1,1-azobis (cyclohexanecarbonitrile) (Vazo 88 from DuPont), 0.15 parts of glycidoxypropyltrimethoxysilane, 4.0 parts of glass bubbles C15 / 250, and 4.0 parts of Cab-O-Sil M5. The mixture is then degassed and applied as a knife-type coating to a thickness of about 1 mm between 0.05 mm thick silicone-coated polyester films, and cured as described in Example 1. The light intensity is 2.25. mW / cn2 above the network, and 1.77 mW / cm2 below the network. The total energy above the network is 225 mJ / 'cm2 and 177 mJ / cm2 below the network. A melt-flowing layer is repaired, according to the procedure of Example 1, by the following composition: 60 parts of BA, 40 parts of NVC, 80 parts of B60, 80 parts of HDGEBA, 0.14 parts of KB-1. , 0.10 parts of Irganox ^ lOlO, 6 parts of DICY, 3 parts of 2MZ Azine, and 4.5 parts of Cab-O-Sil M5. The mixed composition is then degassed, the top film is removed from the expandable layer, and the composition of the melt flowable layer is applied as a knife-like coating to a thickness of 1.25 mm at the top of the expandable layer !, and Covers with a film coated with 0.05 mm thickness. The coated sheet is cured with lamps as described in Example 1 with a light intensity of 2.3 mW / cm2 above the network and 2.1 mW / cm2 below the network. The total energy is 550 mJ / cm2 above the network and 503 mJ / cm2 below the network.

The film is removed from the expandable layer side of a sample measuring 1.9 cm by 7.6 cm, and the expandable layer is laminated to a steel panel that has been electrocoated with PPG-ED-5100 (from Advanced Coatings Technology, Inc.) . The film on the melt-flow side is then removed and the sample is heated at 177 ° C for 12 minutes After cooling, the sample is examined for sealing and appearance. The lower layer of the sample has been completely encapsulated and sealed by the top layer to produce a regular, paintable and environmentally resistant surface after heat curing.

Examples 37-44 The layers for these examples can be used as a top layer or as a bottom layer in a sheet construction. For each example, a composition is produced by mixing 80 parts of BA, 20 parts of NNDMA, and 80 parts of Epon ^ lOOl. The various polycaprolactone ions are added in the parts by weight shown in Table 5. The polycaprolactone polyols are heated to about 70 ° C before being added to the epoxy / acrylate mixture. The melt-flow side is then removed and the sample is heated at 177 ° C for 12 minutes. After cooling, the sample is examined for its sealing and appearance. The lower layer of the sample is completely encapsulated and sealed by the top layer to produce a regular surface, which can be painted and environmentally resistant after thermosetting.

Examples 37-44 The layers of these examples can be used as a top layer or as a bottom layer in a sheet construction. For each example, a composition is formed by mixing 80 parts of BA, 20 parts of NNDMA, and 80 parts of EponMR1001. Are various polycaprolactone ions added in the parts by weight shown in the Table? . The polycaprolactone polyols are heated to about 70 ° C before being added to the epoxy / acrylate mixture. The remaining ingredients are added using a high shear mixer: 0.16 parts of KB-1, 0.1 parts of Irganox ^ lOlO, 2.8 parts of DICY, 1.2 parts of HINP, 4 parts of C15 / 250 glass bubbles and 4 parts of silica Cab-O-Sil M5. After degassing under vacuum, the mixtures are applied with a knife-like coating to a thickness of 2 mm between two polyester release coating materials coated with 0.05 mm of silicone. The coated mixtures are cured with ultraviolet light as described in Example 1 with a total energy of 341 mJ / cm2 above the network and 310 mJ / cm2 below the network. The intensity is 1.87 mW / cm2 above the grid and 1.66 mW / cm2 below the network. The layers are tested for their resistance to stress, elongation and vertical flow, and the results in Table 5 show how the polycaprolactone polyols can be used to modify the flow properties as well as the physical properties of the sheet.

* The sample does not break; the maximum information is presented. TEST A - Detachment 90 ° - N / dm TEST B - Resistance to tearing by cured overlap - MPA TEST C Resistance to the initial tension - MPa TEST D Initial elongation -% TEST E Resistance to tension in curing - MPa TEST F Elongation in curing -% TEST G Hardness in curing - Shore A hardness test system) TEST H Vertical flow - mm TEST I Adhesion to paint Examples 45-50 Single layers are prepared using a polyester polymer (DynapolMRS1402) and polycaprolactone polymers (TONE ^ OO and TONEMRP767E) to alter the properties of the sheet materials in these examples. The layers can be used as a top layer or as a bottom layer.

The basic formulations are the same for all the examples but different amounts and types of polymers were added as shown in Table 6. The materials used in the basic formulation were: BA-80; NNDMA -twenty; EPON ^ lOOl-80; KB-1 - 0.16; DICY - 2.8; HINP - 1.2; C15 /: 50 - 4; Cab-O-Sil 5 - 4. The polymers were mixed with BA, NNDMA and epoxy material and heated, with occasional stirring to about 70 ° C to melt the polymers and form molten solutions. The remaining components (catalyst, accelerator, photoinitiator and fillers) were added to the solutions (which have been cooled to room temperature) with a high shear mixer and degassed. Leaves (2.0 mm thick) are prepared as described in Example 36. Examples 45-48 were cured with a total curing energy of 341 mJ / cm2 above the network and 310 mJ / cm2 below of the network, and an intensity of 1.87 mW / cm2 above the network and 1.66 mW / cn2 below the network. The total energy for examples 49-50 was 343 mJ / cm2 above the grid and 304 mJ / crr2 below the grid, and the intensity was 2.07 ra / ct? 2 above the grid and 1.83 mW / cm2 below the network. : the tests are how they are used.

Examples 51-53 An adduct of a diglycidyl ether of bisphenol A (DGEBA) and 2-isocyanatomethyl methacrylate (IEM) is prepared by charging the following materials, under an atmosphere of dry air, to a 500 ml three-necked round bottom flask equipped with a mechanical agitator, a reflux condenser? a thermometer: 200 grams of EponMR828, 10.06 grams of IEM (from Dow Chemical Co.), and 6 drops of dibutyl tin dilaurate. The flask is immersed in an oil bath and heated at 65 ° C for about 5 hours until it is not possible to detect residual isocyanate by infrared. The reaction product (DGEBA / IEM adduct) is allowed to cool to room temperature and placed in an amber bottle, a 50/50 mixture of BA and NVC is heated to about 50 ° C to form a solution. A mixture (MIX) is prepared by mixing 400 parts of the BA / NVC solution, 600 parts of BA and 1,000 parts of Epon ^ 100l. The mixture is further compounded with fillers and catalysts as shown in Table 11 and 2.0 mm thick sheets are prepared as described in Example 19. The sheet is substantially free of tack. The test data in Table 11 indicate that the stiffness of the sheet material increases significantly without affecting the flow properties in function.

Table 7 Example 51 52 53 MIX 1400 200 200 KB-1 0.7 0.7 0.7 IRG 1010 0.7 0.2 0.2 DICY 24.5 3.5 3.5 HINP 8.75 1.25 1.25 CBr4 5.6 0.8 0.8 C15-250 28 M5 35 ADUCT DGEBA / IEM 10 Flow in Fusion Shear by superposition 836 777 700 curing - MPa * Stiffness ratio ** - 0.0 / 0.24 / 53 / Torsion / viscous nodule 0.0 0.08 29 (inches pounds) * All faults are cohesive * * The stiffness ratio is calculated on a Monsanto MDR areometer of moving die), - test conditions - oscillating at 0.5 °, at 177 ° C for 30 minutes.

Example 54 Three sheets of material layers are made according to the procedure described in Example 36. The melt flowable layer has the same composition as the melt flowable layer of Example 36 and is applied as a coating to a thickness of 1.5 mm. The light intensity is 2.46 mW / cm2 above the grid and 2.03 mW / cm2 below the network. The total energy is 354 above the network and 292 mW / cm2 below the network. An expandable, pressure-sensitive layer having the same composition as the expandable layer of Example 36, except that it has been applied as a knife coating to a thickness of 0.12 mm and cured with a light intensity of 2.21 mW / cm2 above the network and 1.76 mW / cm2 below the network. The total energy is 168 by the grid, and 134 mW / cm2 below the network. An expandable layer with the same composition as the expandable layer of Example 36 except that 1 part of hexanediol diacrylate was used, and the composition was applied as a coating to a thickness of 0.75 mm. The composition is cured with a light intensity of 2.20 mW / cm2 above the grid and 1.75 mW / cm2 below the network. The total energy is 251 mW / cm2 above the grid and 200 mW / cm 'below the network.

The sheet material is prepared by laminating the expandable layer; pressure sensitive on the expandable layer, and then laminate the meltable layer by melting on the surface; exposed from the expandable layer. The sheet material is subjected to thermosetting as described in Example 36. After cooling, the sample exhibits good bonding to the panel, and the complete encapsulation and sealing of the pressure-sensitive layers and expandable by the melt-flowable layer produce a regular surface, which can be painted and resistant to environment.

Examples 55-60 A premix composition is prepared as described in Example 1 having a composition of 80 parts of butyl acrylate, 20 parts of N-vinylcaprolactam and 30 parts of poly (vinylbutyral) (ButvarRB''9) available from Monsanto Co. ). The following were added in the amounts shown in Table 8 and mixed with a high shear mixer for approximately 20 minutes: DGEBA, KB-1, Irg 1010, HDDA, DICY, 2MZ Azine, PMMA and VAZO ^ ßß. The resulting mixtures are then transferred to glass containers, sealed and gently agitated in a mechanical stirrer.

The blends are then applied as a knife-like coating to a thickness of approximately 1.25 mm between two silicone-coated polyester release sizes. The coated compositions are cured with UV radiation as described in Example 1 with an intensity of 1.92 mW / cm2 above the network and 1.50 mW / crn2 below the network. The total energy used is 371 mJ / cm2 above the network and 289 mJ / cm2 below the network. The samples are tested to determine their tension and their elongation and their adhesion to the 90 ° detachment. The tensile strength is reported in KiloPascals (kPa) in Table 8. The detachment adhesion test is carried out on an ED5100 electro-coated plate for a retention period of 20 minutes at room temperature. The samples are particularly useful as an environmentally resistant layer either as a single layer or as a multi-layer construction.

The data in Table 8 show that tapes with compositions containing a polymethyl methacrylate macromer have lower values for tensile stress resistance and higher release adhesion values, which are indications of a reduction in molecular weight of the cured compositions.

Example 61-65 Styrene macromers were added to the composition of Example 61 in Examples 62-65. The compositions for the expandable layer were cured and laminated to the polyester film described in Example 24, and a flowable layer as described in Example 54. It is repaired as follows a methacrylate-terminated polystyrene macromonomer (macromer 1) . A 5-liter, flame-dried, 5-neck, glass flask, equipped with a mechanical stirrer, thermometer, gas inlet, condenser and addition funnel, purged with argon and then loaded with 2100 grams of cyclohexane which has previously been distilled from polystyryllithium. The cyclohexane is heated to 50 ° C and 20 ml of a 1.17 molar solution of sec-butyllithium in cyclohexane (23.4 moles) is added to the flask using a syringe. Purified styrene monomer (350 grams) is added in one portion to the flask, resulting in an exothermic reaction. The temperature is maintained at less than 74 ° C by cooling and then during the next hour, the reaction is maintained at about 50 ° C. Subsequently, the mixture is cooled to 40 ° C and ethylene oxide is introduced, which has previously passed over sodium hydroxide, with vigorous stirring, until the red color changes to a light yellow. The reaction is then suspended with 1.4 grams (23.4 millimoles) of acetic acid. The reaction mixture is saturated with dry air, and 10.9 grams (70.2 mmol) of 2-isocyanatoethyl methacrylate (obtained from Dow Chemical Company) and 4 drops of tin dioxatoate catalyst are added. The resulting mixture is heated to 60 ° and held at that temperature for about 14 hours. Subsequently the mixture is cooled and the polymer is precipitated in 30 liters of methanol, dried in vacuo to provide 340 grams of the macromonomer having an average molecular weight number of 16,700, and an average molecular weight of 18,036. Macromer 2 is the styrene macromer RC13K from Sartomer. Example 61 is prepared as in Example 1 except that 50/50 BA / NVC is mixed in a roller mill without heating until the solution is formed. The composition has 80 parts of BA, 20 parts of NVC, 80 parts of DGEOBA (EponM10Cl from Shell Chemical Co.), 20 parts of DGEBA, 4.5 parts of DICY, 1.0 parts of HINP, 0.6 parts of VAZOMR64, 0. 16 parts of glycidoxypropyltri ethoxysilane, 4.0 parts of C15 / 2? 0, 2.5 parts of silica (Cabot Cab-O-Sil M5) Corp.), 0.1 parts of KB-1, 8.0 parts of smoked silica (Aerosil R972 from DeGussa) and 0.8 parts of CBr4. In Examples 62-65, the styrene macromonomer is added to the mixture in the acrylate monomers and the epoxy resins are dissolved in a roller mill. The remaining components are dispersed with a high shear mixer. The mixture is then mixed in a roller mill for about 2 days, the air is removed, applied as a cover and cured as described in Example 1. The sheets are coated to a thickness of approximately 0.051 mm. The leaves are tested for stiffness (G1) of the sheet before heat curing, and the results are shown in Table 9. The leaves are then cured at 177 ° C for 12 minutes and at 121 ° C for 20 minutes, they are cooled to room temperature and tested for tensile strength (in kiloPascals - kPa) and elongation. The results of the test are shown in Table 9. A three layer construction is prepared with the flowable layer of Example 54 (approximately 1.52 mm thick) with the polyester film of Example 24. The thickness of the initial construction and final are shown in Table 9.

The data in Table 9 show that the addition of copolymerizable macromonomers increase the rigidity and tensile strength of the expandable layer to improve handling and at the same time maintain desirable flow characteristics.

E-ie 66-70 Examples 66-70 are prepared using a curative anhydride with tetramethylammonium chloride as the accelerator. A flowable composition is prepared by mixing 30 parts of BA, 20 parts of isobornyl acrylate, 15 parts of macromonotide 1 (Example 61), 35 parts of DGEOBA (Epon ^ 100l), 0.1 part of Irgacure ™ 655 as photoinitiator and 0.2 part of CBr2. . The anhydride which functions as the polymeric agent for resins (1,2-cyclohexa dicarboxylic anhydride and accelerator (tetramethyl chloride, Lamonium) is added in amounts shown in Table 10. The compositions are removed from the air, applied as a coating of blade type to a thickness of about 2 mm and cured as described in Example 1 with an exposure to approximately 650 mJoules of UV radiation.The UV cured samples are then tested for temperature onset, peak exothermic temperature and exotherm (Joule / gram) and a differential scanning calorimeter from DuPont.The results are shown in Table 10. The cutting samples are also cured at 177 ° C for 30 minutes and all of the samples exhibit good flow properties. to say, they flow beyond the boundaries of the initial belt The melt-flowable sheets of these examples can be laminated to expandable layers as described above.

The data in Table 10 show that by varying the amount of polymerizing agent for resins the temperature which cures the epoxy component can change, therefore a greater or lesser time is allowed for the composition to flow before curing.

Examples 71-74 A composition is prepared having 25 parts of a solution of BA / NNDMA / ButvarMRB79 in a 60/40/30 ratio, 5 parts of BA, 10 parts of DGEBA, 2 parts of 1,2-cyclohexanedicarboxylic anhydride, 0.05 parts of chloride of tetramethylammonium, 0.05 parts of HDDA, 0.1 parts of Irg 1010, 0.40 parts of Irgacure ^ dSl and 0.15 parts of glycidoxypropyltrimethoxysilane. Variable amounts of acrylic acid, sodium bicarbonate and carbon tetrabromide are added, as shown in Table 11. The compositions were coated and cured as described in Example 1. After heat curing, the sheets are they observe qualitatively for expansion (positive or negative) and for flow during heat curing (positive or negative) and the results are reported in Table Ll.

The data in Table 11 show that sodium bicarbonate can be used as an expanding agent in the expandable layer, and varying amounts of the other components can be used to modify the properties as desired. It will be apparent to those skilled in the art that various modifications and variations may be made to the method and article of the present invention without departing from the spirit or scope of the invention. Therefore, it is considered that the present invention encompasses the modifications and variations of this invention insofar as they fall within the scope of the appended claims and their equivalents. It is noted that in relation to this date, the best method known by the applicant to carry out the aforementioned invention, is the conventional one for the manufacture of the objects to which it relates. Having described the invention as above, property is claimed as contained in the following:

Claims (5)

1. A melt-curing, thermosetting, latent sheet material having an upper surface and a lower surface, comprising two or more layers, comprising an upper layer and a lower layer, the sheet material is characterized in that the upper layer comprises a melt-flowable, thermosetting, latent composition, and the bottom layer is comprised of a melt-flowable, thermosettable, latent expandable composition in which, by application of the sheet material to a substrate upon contacting the bottom surface with the same, and heat at an elevated temperature, the lower layer expands and the upper layer flows; and wherein the upper and lower layers comprise a macromonomer.

2. The melt-flowable, thermosetting, latent sheet according to claim 1, characterized in that the upper layer comprises a macromonomer.

3. The melt-flowable, thermosetting, latent sheet according to claim 1, characterized in that the lower layer comprises a macromonomer.

4. The melt-curing, thermosetting, latent sheet according to one of claims 1 to 3, characterized in that the macromonomer is a copolymerizable macromonomer.

5. The melt-curing, thermosetting, latent sheet according to one of claims 1 to 4, characterized in that the macromonomer is a macromonomer which functions as a chain transfer agent. RESDMEN OF THE INVENTION A meltable, thermosetting, latent, melt-flowable sheet material is provided, consisting of at least two layers, one. of which is expandable and flowable, and the other of which flows to encapsulate the expandable layer therebetween and a substrate to which the sheet material has adhered. A melt-curing, thermosetting, latent sheet material which can be cured to provide an environmentally resistant layer is also described. Additionally, a method for imparting topographic or protective features to a substrate such as a metal gasket or automotive body is described.