DE19902685A1 - Urethane (meth)acrylate, useful for the production of coatings for flat roof and parking decks, has at least 3 terminal ethylenically unsaturated reactive groups. - Google Patents

Abstract

A urethane (meth)acrylate having at least 3 terminal, ethylenically unsaturated reactive groups is prepared by reaction of a hydroxyalkyl(meth)acrylate with a polyisocyanate and a polyoxyalkylene that has at least 3 hydroxy groups and has a polyethylene oxide content of less than 50 wt.%. A urethane(meth)acrylate (I) has at least 3 terminal ethylenically reactive unsaturated groups and is prepared by reaction of (A1) a hydroxyalkyl(meth)acrylate with (A2) a polyisocyanate and (A3) a polyoxyalkylene that has at least 3 hydroxy groups and has a polyethylene oxide content of less than 50 wt.%.or (B1) a hdyroxyalkyl(meth)acrylate with (B2) a mixture of polyisocyanates of which at least one has at least 3 isocyanate groups and (B3) a polyoxyalkylene that has at least 3 hydroxy groups and has a polyethylene oxide content of less than 50 wt.%. An Independent claim is included for a process for the production of (I) by reaction of a hyroxyalkyl(meth)acrylic acid ester with at least one polyisocyanate and at least one polyoxyalkylene.

Description

The invention relates to novel urethane (meth) acrylates, Processes for their production and their use, especially in (meth) acrylate resins, which for the Surface protection of traffic areas, especially bridges; and parking decks, from flat roofs, for backfeeding of bathtubs or in general for floor and Wall coatings and seals are used.

Bridges can be made by plastic coatings that are considered Membrane between concrete carriageway slabs and mastic asphalt be applied against damage caused by water ingress, De-icing salt solutions and diluted acids (acid rain) to be protected. For this are (meth) acrylate resins basically suitable, their flexibility at low However, temperatures are insufficient.

As a measure of the flexibility of a resin is in the frame elongation at break of the present invention understood the tensile strength. These two mechanical Properties of a resin are generally opposed to one another, so a resin with a high elongation at break very often only has a low tensile strength.

As a further measure of the flexibility of a resin, the Ability to serve crack bridging. A measuring method for This property is determined, for example, in "Additional technical contract conditions and Guidelines for protection and repair of Concrete Components (ZTV-SIB 90) ", published by Federal Minister of Transport (1990).

Additives that increase the flexibility of (meth) acrylate resins increases are known per se and commercially available, so for example difunctional urethane (meth) acrylates.  

A disadvantage of these substances is that they are relatively large Amounts must be used. This leads in particular to high cost because they are quite expensive. Furthermore, it is Improvement achieved by adding these substances may not be sufficient for many purposes.

In view of the state of the art, it was the task of present invention additives for (meth) acrylate resins specify the flexibility of (meth) acrylate resins increase, especially at low temperatures.

Another task was to specify substances that increase the tensile strength of the (meth) acrylate resins.

Furthermore, it was an object of the present invention To provide fabrics that have the elongation at break of Improve (meth) acrylate resins, especially at deep ones Temperatures.

In addition, (meth) acrylate resins, which the Contain additives, insensitive to Temperature fluctuations.

The additives should be as inexpensive as possible be producible.

The amount of additives needed to achieve the desired effect is needed, should be as low as possible his.

These tasks are solved as well as others that are not to be called literally, but deriving from the here derive discussed contexts as a matter of course let or inevitably result from these, by Urethane (meth) acrylates with all the characteristics of the independent Claim 1.  

Advantageous embodiments of the invention Urethane (meth) acrylates are the subject of the independent product claim related claims.

With regard to the method according to the invention Claim 7 the solution to the underlying problem, wherein preferred embodiments in the related to Claims are explained. Uses according to the invention are presented in claim 10.

The fact that urethane (meth) acrylates with at least 3 reactive terminal ethylenically unsaturated functionalities, obtainable by the reaction of

• A) a) Hydroxyalkyl (meth) acrylic acid esters with
• B) polyisocyanates and
• C) polyoxyalkylenes, the
  • 1. have at least three hydroxy functionalities,
  • 2. wherein the proportion of polyethylene oxide is less than 50 wt .-%, based on the total amount of polyoxyalkylene, or
• D) a) Hydroxyalkyl (meth) acrylic acid esters with
• E) mixtures of polyisocyanates, of which at least one polyisocyanate 3 or more Has isocyanate groups, and
• F) polyoxyalkylenes, the
  • 1. have at least two hydroxy functionalities,
  • 2. the proportion of polyethylene oxide being less than 50% by weight, based on the total amount of polyoxyalkylene,

used as an additive in (meth) acrylate resins, the Resin flexibility at low temperatures essential elevated.

Furthermore, the following advantages are achieved by the present invention:

• - The additives according to the invention allow a change the requirements perfectly adaptable Property spectrum.
• - The elongation at break is significantly increased if this Value compared with that of resins, the one have comparable tear strength.
• - The tensile strength is improved if this value compared to that of resins, the one have comparable elongation at break.
• - By adding the urethane (meth) according to the invention - acrylate is compared to the stability Temperature fluctuations increased.
• - To achieve a desired improvement in flexibility To achieve low temperatures, it is sufficient to use the urethane (meth) acrylates according to the invention in relative small quantities, which creates cost advantages.
• - For use in floor and wall coatings by the additives according to the invention Brittleness specifically reduced depending on the amount used or the impact strength of the coating is increased. This applies in the same way to the sealing of a Coating.
• - Furthermore, the inventive Additives smoother surfaces and better  dirt - repellent properties of the coatings and Achieve seals.
• - Furthermore, when applying a resin for the Floor coating the course through the additives according to the invention improved.
• - Finally, improve the invention Additives the adhesion between a coating and their sealing.

Urethane (meth) acrylates in the context of the present Invention Compounds that have (meth) acrylate functionalities have linked together via urethane groups are.

Urethane (meth) acrylates according to the invention have at least three reactive terminal ethylenically unsaturated Functionalities derived from (meth) acrylates are.

They are by the implementation of hydroxyalkyl (meth) - acrylic acid esters with polyisocyanates and polyoxyalkylenes, which have at least three hydroxy functionalities, where the proportion of polyethylene oxide is less than 50% by weight, based on the total amount of polyoxyalkylene available.

The term (meth) acrylic acid denotes herein Methacrylic acid, acrylic acid and mixtures of these acids.

Hydroxyalkyl (meth) which can be used according to the invention acrylic acid esters are esters of (meth) acrylic acid with dihydric, aliphatic alcohols. These connections are well known in the professional world. You can for example by the reaction of (meth) acrylic acid with Oxiranes can be obtained.  

The oxirane compounds include, among others Ethylene oxide, propylene oxide, 1,2-butylene oxide and / or 2,3- Butylene oxide, cyclohexene oxide, styrene oxide, epichlorohydrin and Glycidyl ester. These connections can be both individually and can also be used as a mixture. Implementation to the Hydroxyalkyl (meth) acrylic acid esters are, for example, in DE-A-24 39 352, DE-15 68 838 and GB 1 308 250.

The hydroxyalkyl (meth) acrylic acid esters obtainable in this way are often commercially available and therefore for the purposes according to the invention are particularly suitable.

The hydroxyalkyl (meth) acrylic acid esters can also Substituents such as phenyl or Amino groups included. Furthermore, the Hydroxyalkyl radical of the ester also polyoxyalkylene groups included that are both linear and branched can, such as polyethylene oxide, Polypropylene oxide and polytetramethylene oxide. These groups often have between 2 and 10 oxyalkyene units.

Preferred hydroxyalkyl (meth) acrylic acid esters are among other hydroxyethyl acrylate, hydroxyethyl methacrylate, 2-hydroxypropyl acrylate, 2-hydroxypropyl methacrylate, 3-hydroxypropyl acrylate, 3-hydroxypropyl methacrylate, 6-hydroxyhexyl acrylate and 6-hydroxyhexyl methacrylate, 3-phenoxy-2-hydroxypropyl methacrylate, Polyethoxymethacrylate, polypropoxymethacrylate, Polyethylene oxide / polytetramethylene oxide methacrylate, Polyethylene oxide / polypropylene oxide methacrylate, acrylic acid (4-hydroxybutyl ester), acrylic acid (2-hydroxyethyl ester), Methacrylic acid (hydroxymethylamide), caprolactone hydroxy ethyl methacrylate and caprolactone hydroxyethyl acrylate, of these are hydroxyethyl methacrylate, hydroxyethyl acrylate, Whole 2-hydroxypropyl methacrylate and 2-hydroxypropyl acrylate particularly preferred.  

In the context of the present, designate polyisocyanates Invention of low molecular weight compounds. Two or contain several isocyanate groups.

By choosing the proportion of polyisocyanates with 3 or more Isocyanate groups can be the property spectrum of Set elongation at break and tensile strength. The higher the Share of connections with three or more functionalities the greater the tensile strength. This takes however, the elongation at break greatly decreases. Accordingly found that the proportion of these polyisocyanates with three or more functionalities not larger than 10% by weight, preferably not more than 5% by weight, based on the Total mass of polyisocyanates should be. This However, explanations only refer to the Production of the urethane (meth) acrylates according to the invention according to embodiment A). In embodiment B), in the polyoxyalkylenes which have two hydroxyl groups, linked via polyisocyanates, the three or more Have isocyanate groups, is the proportion of Polyisocyanates with three or more functionalities accordingly larger.

Among those usable in the present invention Polyisocyanates include, among others 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-dicyclohexyl diisocyanate, meta- and para-tetramethyl xylene diisocyanate, 3-isocyanatomethyl-3,5,5- trimethylcyclohexyl isocyanate (isophorone diisocyanate), Hexamethylene diisocyanate, 1,5-naphthylene diisocyanate, Dianisidine diisocyanate, di (2-isocyanatoethyl) - bicyclo [2.2.1] -hept-5-ene-2,3-dicarboxylate, 2,2,4- and 2,4,4-trimethylene hexamethylene diisocyanate, triphenylmethane 4,4 ', 4 "triisocyanate, tris- (4-isocyanatophenyl) - thiophosphate, and mixtures thereof.  

Suitable polyisocyanates can also, for example, by the implementation of polyhydric alcohols with diisocyanates or obtained by the polymerization of diisocyanates become. Polyisocyanates can also be used, by reacting with hexamethylene diisocyanate small amounts of water can be represented. These products contain biuret groups.

These connections are well known in the art and for the most part commercially available. This includes among others ®Desmodur H, ®Desmodur N 100, ®Desmodur N 3300 (from BAYER), ®Basonat PLR 8401, ®Basonat PLR 8638 (from BASF), ®Tolonate HDB 75 MX, ®Tolonate HDT 90 (from Rhône Poulenc), ®Vestanat IPD, ®Vestanat T 1890/100 and ®Vestanat T 2960 (from Hüls).

Compounds whose isocyanate groups are preferred have different reactivities. This attribute facilitates the conduct of the reaction without this Restriction should take place. An example of such preferred polyisocyanate is isophorone diisocyanate.

Suitable polyisocyanates in the context of the present Invention also the analog isothiocyanates. This one however, are less commercially available these compounds less preferred.

Polyoxyalkylenes containing at least three hydroxy can have functionalities, for example, by Polyaddition of cyclic ethers, such as Oxiranes and tetrahydrofuran can be obtained.

To the oxiranes used for polyaddition can include those mentioned above. Of propylene oxide is preferred.

To get at least three hydroxy functionalities, the can react with isocyanate groups  for example, alcohols are used as starting molecules that have at least three hydroxyl groups.

These include glycerin, trimethylolpropane, Erythritol, pentaerythritol, sorbitol and inositol, of these is Preferred glycerin.

The polyaddition of cyclic ethers to polyvalent ones Alcohols are well known in the art. Valuable The expert can find information, for example, in Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., Keyword "Polyoxyalkylene".

Furthermore, polyoxyalkylenes, the three or more Have hydroxy functionalities, also produced in situ become. This is achieved through variant B) by Polyoxyalkylenes with two hydroxy functionalities Polyisocyanates with three or more isocyanate groups be linked.

The weight average molecular weight of the Polyoxyalkylenes can vary widely. It is preferably in the range from 2000 to 20,000, preferably in the range from 4000 to 10,000 and entirely particularly preferably in the range from 4000 to 80,000 g / mol. It is essential, however, that the polyether chains have a minimum Induce flexibility. Accordingly, the Chain length of the polyether chains larger than on average 10 units, preferably larger than 20 units and whole preferably be greater than 30 units.

The above cyclic ethers can also be used as Mixture are used, resulting in copolymers. Block copolymers of this type are also used become.

Polyethylene glycols (PEG) are hygroscopic. The stake of these polymers in acrylic resins, for example  concrete bridges are used for surface protection therefore not recommended. It freezes through the cold PEG absorbed water and expands. This Expansion may cause cracking in the resin and thus to the destruction of the surface protection to lead. Therefore the proportion of polyethylene oxide should be smaller than 50% by weight, based on the total amount Polyoxyalkylene. It is preferably less than 25% by weight, particularly preferably less than 15% by weight.

Some polyoxyalkylenes with at least three Hydroxy functionalities are commercially available.

Preferred polyoxyalkylenes are polyoxypropylenes. Prefers can also be polytetramethylene oxides, which together with the polyoxypropylenes can be used, these Polyoxyalkylenes each have at least three reactive, have terminal hydroxy functionalities.

It is assumed that at least some of the urethane (meth) acrylates according to the invention can be represented by the following formula (I):

wherein
R ^{1 is} hydrogen or methyl,
R ^{2 is} a linear or branched alkylene group with 2 to 20 carbon atoms or alkylene oxides with 4 to 50 carbon atoms,
R ^{3 represents} an aromatic, aliphatic or cycloaliphatic group containing up to 18 carbon atoms, which are derived from diisocyanates or diisocyanate mixtures,
R ^{4 represents} an alkylene radical having at least 2 carbon atoms, provided that at least half of all R ⁴ radicals in the urethane (meth) acrylate of the formula (I) have 3 or more carbon atoms,
m is an integer ≧ 1,
n is an integer ≧ 10,
x an integer ≧ 3 and
Z is a connecting group derived from alcohols with at least three hydroxyl groups or from polyisocyanates with at least three isocyanate groups.

The term "alkylene" means a divalent radical that by removing two hydrogen atoms from each a non-adjacent carbon atom original hydrocarbon is obtained and includes Alkylenes of 3 to 18 carbon atoms, inclusive for example 1,3-propylene, 1,4-butylene, 1,5-pentylene, 1,8-octylene and 1,10-decylene. These residues can be branched be linear as well. Furthermore, these groups also be substituted.

The groups R ² to R ⁴ and the numbers m and n are derived from the starting materials used in the reaction. These are described above. Accordingly, m is preferably equal to 1, but to increase the tensile strength, polyisocyanates with three or more functionalities can also be used, so that consequently some of the molecules can be represented by formulas in which m <1.

The connecting group Z and the number x are also dependent on the starting materials. In addition, the radical Z and the parameter x can also be influenced by the reaction procedure and the quantitative ratios of the starting materials. If, for example, glycerol is chosen as Z, it is also possible, among other things, for connecting groups of the formula (II)

are formed, which can be formed by coupling two polyoxyalkylenes with polyisocyanates, where R ³ , R ⁴ and n have the meaning given above. However, the formation of macromolecules is also conceivable, which result from the coupling of more than two polyoxyalkylenes.

Particularly preferred urethane (meth) acrylates of the present Invention have three or four reactive terminal ethylenically unsaturated functionalities.

The urethane (meth) acrylates according to the invention can be prepared by processes in which

• a) at least one hydroxyalkyl (meth) acrylic acid ester With
• b) at least one polyisocyanate and
• c) at least one polyoxyalkylene

implements.  

Various reactions are conceivable here. So can Urethane (meth) acrylates of the present invention in one two-step synthesis. Here are for example equimolar amounts of hydroxyalkyl (meth) - acrylic acid ester and polyisocyanate, after which the reaction product thus obtained with an appropriate amount Polyoxyalkylene can react. When choosing more suitable Polyisocyanates or by a skillful reaction In particular, urethane (meth) acrylates with three reactive terminal ethylenically unsaturated Get functionalities.

It is also conceivable to implement it in one step perform. This creates a mixture Different numbers of urethane (meth) acrylates of ethylenically unsaturated functionalities. It has shown that when using trifunctional Polyoxyalkylenes are often tetrafunctional Urethane (meth) acrylates with connecting groups of Formula (II) are created, as exemplified above are shown. The mixtures thus obtained can be used as Additive in the (meth) acrylate resins without further Purification can be used.

The reaction can be carried out in bulk, i.e. H. without using a further solvent can be carried out. If if desired, an inert solvent can also be used become. These include benzene, toluene and Methyl isobutyl ketone (MIBK), methyl ethyl ketone (MEK).

The reaction of the isocyanate groups with the hydroxy groups is well known in the professional world. So it can Vary reaction temperature over a wide range, but often the temperature is in the range of 30 ° C to 120 ° C, preferably in the range of 60 ° C to 90 ° C. The same applies to the pressure during the implementation is carried out. So the reaction can be both under negative pressure  as well as with overpressure. It is preferred but carried out at normal pressure. The reaction can take place under Air as well as take place under a protective gas atmosphere, whereby there is preferably a small amount of oxygen, since this inhibits possible polymerization.

To speed up the implementation are common Catalysts, such as tertiary amines, to these include, among others, 1,4-diazabicyclo [2.2.2] octane, N-methylmorpholine, N, N-diethylcyclohexylamine and N.N.N ', N'-tetramethyldiaminomethane, or organic Tin compounds, these include, among others Dibutyltin dilaurate and tin dioctoate. This Catalysts as well as the amounts in which these compounds are widely known in the professional world and for example in Ullmann's Encyclopedia of Industrial Chemistry, 5th ed., Keyword "Polyurethanes".

Inhibitors can be added during the reaction a radical polymerization of the (meth) acrylates during prevent the reaction. These inhibitors are in the Experts are well known.

Mainly 1,4-dihydroxybenzenes are used. However, differently substituted dihydroxybenzenes can also be used. Such inhibitors can generally be represented by the general formula (III)

wherein
R ^{1 is} a linear or branched alkyl radical having one to eight carbon atoms, halogen or aryl, preferably an alkyl radical having one to four carbon atoms, particularly preferably methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec -Butyl, tert-butyl, C1, F or Br;
n is an integer ranging from one to four, preferably one or two; and
R ^{2 is} hydrogen, a linear or branched alkyl radical having one to eight carbon atoms or aryl, preferably an alkyl radical having one to four carbon atoms, particularly preferably methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec -Butyl or tert-butyl.

However, compounds with 1,4-benzoquinone as the parent compound can also be used. These can be described with the formula (IV)

wherein
R ^{1 is} a linear or branched alkyl radical having one to eight carbon atoms, halogen or aryl, preferably an alkyl radical having one to four carbon atoms, particularly preferably methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec -Butyl, tert-butyl, Cl, F or Br; and
n is an integer in the range from one to four, preferably one or two.

Phenols of the general structure (V) are also used

wherein
R ^{1 is} a linear or branched alkyl radical with one to eight carbon atoms, aryl or aralkyl, propionic acid ester with 1 to 4-valent alcohols, which may also contain heteroatoms such as S, O and N, preferably an alkyl radical with one to four carbon atoms, particularly preferably methyl , Ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl.

Another advantageous class of substances are hindered phenols based on triazine derivatives of the formula (VI)

with R = compound of the formula (VII)

wherein
R ¹ = C _n H _{2n + 1}
with n = 1 or 2.

Connections 1,4- Dihydroxybenzene, 4-methoxyphenol, 2,5-dichloro-3,6- dihydroxy-1,4-benzoquinone, 1,3,5-trimethyl-2,4,6-tris- (3,5- di-tert-butyl-4-hydroxybenzyl) benzene, 2,6-di-tert-butyl-4- methylphenol, 2,4-dimethyl-6-tert.butylphenol, 2,2-bis [3,5-bis (1,1-dimethylethyl) -4-hydroxyphenyl-1- oxoperopoxymethyl)] 1,3-propanediyl ester, 2,2'- Thiodiethylbis- [3- (3,5-di-tert.butyl-4- hydroxyphenyl)] propionate, octadecyl-3- (3,5-di-tert.butyl-4- hydroxyphenyl) propionate, 3,5-bis (1,1-dimethylethyl-2,2- Methylenebis (4-methyl-6-tert.butyl) phenol, tris- (4- tert-butyl-3-hydroxy-2,6-dimethylbenzyl) -triazine-2,4,6- (1H, 3H, 5H) trione, tris (3,5-ditert.butyl-4-hydroxy) -s- triazine-2,46- (1H, 3H, 5H) trione or tert-butyl-3,5- dihydroxybenzene used.

Based on the weight of the entire reaction mixture is the proportion of the inhibitors individually or as Mixture generally 0.01-0.5% (wt / wt).

Many of these inhibitors are commercially available.

The invention also relates to the use herein Described urethane (meth) acrylates according to the invention for the surface protection of flat roofs and traffic areas, especially bridges and parking decks, for backfeeding of bathtubs or for coatings and seals.

The urethane (meth) acrylates according to the invention can used for example as an additive for (meth) acrylate resins that are used to coat floors, concrete bridges, Flat roofs and parking decks, especially for improvement the flexibility at low temperatures, so for example increasing the ability to  Crack bridging, the improvement of the elongation at break and the Tear resistance, as well as for the backing of bathtubs be used. In these (meth) acrylate resins, the Urethane (meth) acrylates in amounts greater than 5% by weight used, otherwise the improvement of flexibility is insufficient at low temperatures. The use of Amounts above 30% by weight are possible, but from not preferred for economic reasons, since then none substantial improvement in properties occurs more.

(Meth) acrylate resins for floor coatings can consist, for example, of the following components:

• 1. A) (meth) acrylate 50-100% by weight C ₁ -C ₆ (meth) acrylate 0-100% by weight ≧ C ₇ (meth) acrylate 0-50% by weight polyvalent (meth) acrylates 0-10% by weight Comonomers 0-50% by weight Vinyl aromatics 0-30% by weight Vinyl ester 0-30% by weight the components of component A) giving 100% by weight,
• 2. 0-2 parts by weight per 1 part by weight A) one in A) soluble or swellable (pre) polymers,
• 3. 5 to 30 parts by weight per 100 parts by weight (A + B) at least one of the invention Urethane (meth) acrylate,
• 4. 0.1 to 5 parts by weight per 100 parts by weight (A + B + C) at least one paraffin and / or wax,
• 5. one up to the polymerization of the polymerizable Components of the system at least in relation to one Component of the redox system to be kept separate Redox system containing an accelerator and one  peroxide catalyst or initiator in an amount sufficient for cold hardening of component A) and
• 6. usual additives.

Component A)

For floor coatings with particular success (Meth) acrylates that can be used include, among others Methyl methacrylate, methyl acrylate, ethyl methacrylate, Ethyl acrylate, propyl acrylate, propyl methacrylate, Butyl acrylate, butyl methacrylate.

Component A) can contain up to 10% by weight of one or more contain polyvalent (meth) acrylates. About the crowd this crosslinker can change the range of properties (Meth) acrylate resins are changed. The higher the percentage the greater the tensile strength. However, takes the elongation at break.

These include di-, tri- and multifunctional connections. Difunctional (meth) acrylates and trifunctional (meth) acrylates are particularly preferred.

• a) Difunctional (meth) acrylates
  Compounds of the general formula:
  wherein R is hydrogen or methyl and n is a positive integer between 3 and 20, such as. B. di (meth) acrylate of propane diol, butane diol, hexane diol, octane diol, nonane diol, decane diol and eicosane diol;
  Compounds of the general formula:
  where R is hydrogen or methyl and n is a positive integer between 1 and 14, such as. B., di (meth) acrylate of ethylene glycol, diethylene glycols, triethylene glycols, tetraethylene glycols, dodecaethylene glycols, tetradecaethylene glycols, propylene glycols, dipropyl glycols and tetradecapropylene glycols;
  and glycerol di (meth) acrylate, 2,2'-bis [p- (γ-methacryloxy-β-hydroxypropoxy) phenylpropane] or bis-GMA, biphenol A dimethacrylate, neopentyl glycol di (meth) acrylate, 2,2'- Di (4-methacryloxypolyethoxyphenyl) propane with 2 to 10 ethoxy groups per molecule and 1,2-bis (3-methacryloxy-2-hydroxypropoxy) butane.
• b) trifunctional or multifunctional (meth) acrylates
  Trimethylolpropane tri (meth) acrylates and pentaerythritol tetra (meth) acrylate.
• c) urethane (meth) acrylates
  Reaction products of 2 moles of hydroxyl group-containing (meth) acrylate monomer with one mole of diisocyanate and reaction products of a urethane prepolymer having two NCO end groups with a methacrylic monomer which has a hydroxyl group, as described, for. B. are represented by the general formula:
  wherein R represents hydrogen or a methyl group, R _{2 represents} an alkylene group and R _{3 represents} an organic radical.

The stated crosslinking monomers a) to c) are either alone or in the form of a mixture of several monomers used.

To very particularly advantageous in the resin according to the invention The polyvalent monomers used belong above all Trimethylolpropane trimethacrylate (TRIM), 2,2-bis-4 (3- methacryloxy-2-hydroxypropoxy) phenylpropane (Bis-GMA), 3,6-dioxaoctamethylene dimethacrylate (TEDMA), 7,7,9-trimethyl-4,13-dioxo-3,14-dioxa-5,12-diaza-hexadecane 1,16-dioxy-dimethacrylate (UDMA) and / or 1,4- Butanediol dimethacrylate (1,4-BDMA).

Component A) can also other comonomers contain with the above (meth) acrylates are copolymerizable. These include a. Vinyl ester, Vinyl chloride, vinylidene chloride, vinyl acetate, styrene, substituted styrenes with an alkyl substituent in the Side chain, such as B. α-methylstyrene and α-ethylstyrene, substituted styrenes with an alkyl substituent on the ring, such as vinyl toluene and p-methylstyrene, halogenated styrenes, such as monochlorostyrenes, Dichlorostyrenes, tribromostyrenes and tetrabromostyrenes, Vinyl and isopropenyl ether, maleic acid derivatives, such as for example maleic anhydride, Methyl maleic anhydride, maleimide, methyl maleimide, Phenyl maleimide and cyclohexyl maleimide, and dienes, such as for example 1,3-butadiene and divinylbenzene.  

The proportion of the comonomers is 50% by weight of the component A) limited, otherwise the mechanical Properties of the polymerized coatings can be adversely affected. The share of Vinylaromatics is here on 30 wt .-% of component A) limited because higher proportions lead to segregation of the Systems can lead. The proportion of vinyl esters is likewise limited to 30% by weight of component A), since harden them insufficiently at low temperatures and tend to have an unfavorable shrinkage behavior.

All of the above monomers, which are in component A) are commercially available.

Component B)

To adjust the viscosity of the reaction resin and the Flow properties as well as for better hardening or other properties of the resin or polymerized coating of components A) Polymer or a prepolymer can be added. This (Pre) polymer should be soluble in component A) or be swellable. On a part by weight A) between 0 and 2 parts by weight of the (pre) polymer are used.

In particular, e.g. B. poly (meth) acrylates as component B) suitable, which are dissolved as a solid polymer in A) can. They can also be used as so-called syrups, i.e. H. as partially polymerized masses of corresponding monomers be used.

Furthermore, a. Polyvinyl chlorides, polyvinyl acetates, Polystyrenes, epoxy resins, epoxy (meth) acrylates, unsaturated polyesters, polyurethanes or mixtures of these or with the above poly (meth) acrylates as  Component B) suitable. The (pre) polymers mentioned can can also be used as copolymers.

Component C)

Component C) was discussed in detail above described.

Component D)

Methacrylate resins tend to harden Air inhibition. This causes the top Resin layers that can come into contact with air in stay sticky and do not get stuck, like the rest of the crowd. To prevent or improve this behavior is therefore the resin paraffins and / or Waxes added, which prefer their concentration are close to the solubility limit. When vaporizing The solubility limit becomes part of the recipe exceeded, a fine paraffin film forms the surface, which is an air inhibition of the upper Resin layers effectively prevented and thus a dry Surface leads.

Waxes and paraffins are generally to non-polar substances that are in the liquid, Loosen uncured resin. With increasing networking during the polymerization, their tolerance increases the resin so that they form a second phase and to the Migrate the surface of the polymerizing resin mass can. You will then be able to make a closed film to form on the surface, and can this mass shut off from atmospheric oxygen. Through this Exclusion of oxygen is the polymerization of the Supported resin on its surface. In particular  the addition of waxes and / or paraffins thus reduces the stickiness of the surface that the inhibitory effect can be counteracted by oxygen.

In principle, all substances that do the above are suitable described behavior of a homogeneous Surface layer formation when falling below the Show solubility limits.

Suitable waxes include paraffin, microcrystalline wax, carnauba wax, beeswax, Lanolin, whale oil, polyolefin waxes, ceresin, Candelilla wax and the like.

However, pataffins have proven to be particularly suitable. These consist predominantly of straight-chain hydrocarbons of the general formula C _n H _{2n + 1} with n = 10-70 and a proportion of iso- and cycloalkanes / - paraffins from 0 to 60%. These waxes obtained from the vacuum distillation cuts of light and medium-sized lubricating oils have the advantage that they are extremely unreactive under the conditions prevailing in (meth) acrylate resins. They are insoluble in water and hardly soluble in low molecular weight aliphatic alcohols and ethers. They are more soluble in ketones, chlorinated hydrocarbons, gasoline, benzene, toluene, xylene and higher aromatics. The solubility decreases with a higher melting point, ie with an increasing molar mass of the wax. The softening points of the macrocrystalline paraffins are between 35 and 72. The products on the market show viscosities at 100 ° C. between 2 and 10 mm ² / s.

Completely refined and deoiled waxes have proven to be preferred for use in methacrylate resins for floor coating. The oil content of these types is a maximum of 2.5%. Products with a softening point between 40 and 60 ° C and a viscosity at 100 ° C of 2.0 to 5.5 mm ² / s are given particular preference.

The waxes and / or paraffins are used in amounts from 0.1 to 5% by weight, preferably up to 1% by weight and very particularly preferably of about 0.5% by weight, based on the total weight of components A) to C) added. Exceeds the amount of wax and / or paraffin added amount of 5% by weight, this can have an adverse effect on the strength of the floor coating. Falls below the added amount of wax and / or Paraffin an amount of 0.1 wt .-%, so the resins harden not stick-free.

Component E)

The resin for floor coatings A) to E) is for Suitable for cold curing, d. H. for polymerization it contains a redox system consisting of an accelerator and one peroxidic catalyst or initiator. The amounts in to which these accelerators and initiators are added, depend on the respective system and by the specialist To determine routine examinations. However, you must go to Cold hardening of component A) is sufficient.

The accelerator is usually used in an amount of 0.01 to 5% by weight, preferably 0.5 to 1.5% by weight to the sum of components A) to D). To the compounds particularly suitable as accelerators include amines and mercaptans, such as for example dimethyl-p-toluidine, diisopropoxy-p- toluidine, n, n-bis (2-hydroxyethyl) -p-toluidine, Dimethylaniline and glycol dimercaptoacetate, where n, n-bis (2- hydroxyethyl) -p-toluidine and dimethyl-p-toluidine as a whole are particularly preferred.  

Organic accelerators can also be used as accelerators Metal salts are used, which are usually in the range of 0.001 to 2 wt .-%, based on the sum of the Components A) to E) are used. These include u. a. Copper naphthenate and copper oleate.

Suitable as a peroxidic catalyst or initiator especially connecting groups such as ketone peroxides, Diacyl peroxides, peresters, perketals and mixtures of Connections of these groups with each other and with not effective hardeners and initiators mentioned.

Compounds such as are particularly preferred for this purpose Methyl ethyl ketone peroxide, acetylacetone peroxide, ketone peroxide, Methyl isobutyl ketone peroxide, cyclohexanone peroxide, Dibenzoyl peroxide, tert-butyl peroxybenzoate, tert-butyl peroxy isopopyl carbonate, 2,5-bis (2-ethylhexanoyl-peroxy) -2,5- dimethylhexane, tert-butylperoxy-2-ethylhexanoate, tert- Butylperoxy-3,5,5-trimethylhexanoate, 1,1-bis (tert- butylperoxy) cyclohexane, 1,1-bis (tertbutylperoxy) 3,3,5- trimethylcyclohexane, cumyl hydroperoxide, tert Butyl hydroperoxide, dicumyl peroxide, bis (4-tert- butylcyclohexyl) peroxydicarbonate, mixtures of ketone Peroxide types, Perester types, and mixtures of two or more of the aforementioned compounds with each other. Of The above compound is dibenzoyl peroxide prefers.

The initiators are usually in an amount in Range from 0.1 to 10% by weight, preferably from 0.5 to 5 wt .-%, based on the sum of components A) to D), used. In the resin, component E) can  the accelerators, e.g. B. Dimethylparatoluidine included be without polymerization at ambient temperature takes place. By adding the remaining components of the Component E) the reaction is started, the Component E) is usually dimensioned such that the (Meth) acrylate system a pot life of 10 minutes to 20 minutes Has. The (meth) acrylate system according to the invention thus contains the full one just before use Component E), component E) is not until use or included only in part, or in other words, that is fully functional redox system up to Polymerization of the polymerizable components of to keep this away, while individual components of the Redox systems already with polymerizable substances can be premixed.

Component F)

Component F) is optional. These include a large number of additives commonly used in (meth) acrylate reactive resin for floor coatings. Examples are:
Setting agents, antistatic agents, antioxidants, bio-stabilizers, chemical blowing agents, mold release agents, flame retardants, lubricants, colorants, flow improvers, fillers, lubricants, adhesion promoters, inhibitors, catalysts, light stabilizers, optical brighteners, organic phosphites, oils, pigments, impact modifiers, reinforcing agents, reinforcing agents, reinforcing agents and plasticizers.

Depending on the application, the proportions of these Additives vary widely. In general however, the quantities are in the range from 0 to 3 Parts by weight per part by weight of components A) to E).

The invention also relates to the use of the present invention described urethane (meth) acrylates in (meth) acrylate resins for the surface protection of bridges, flat roofs and Parking decks, for the backing of bathtubs or for Coatings and seals.

In the following the present invention with reference to Examples explained in more detail, but none Restriction should take place.

1. Synthesis of urethane (meth) acrylates Example 1) Production of trifunctional urethane methacrylate in a two-stage implementation

0.3 mol of IPDI and 3.10 ^-4 mol of dibutyltin dilaurate (DBTDL) are placed in a round-bottom flask with a reflux condenser, thermometer, stirrer and dropping funnel. This mixture is heated to 80 ° C. For this purpose, a total of 0.3 mol of hydroxyethyl methacrylate (HEMA), to which 500 ppm of 2,6-di-tert-butyl-A-methylphenol (Fluka), based on the expected amount of the end product, was added over a period of 30 minutes , added with stirring. After the addition, the temperature is kept at 80 ° C. until the content of isocyanate groups has dropped to half, with a nitrogen-oxygen mixture with about 7% by volume oxygen being above the mixture. The content of isocyanate groups was determined in accordance with DIN 53 185, from 12. 1974. Generally, this step took about 5 hours.

Then another 3. 10 ^-4 moles of DBTDL added. 0.1 mol ®Voranol CP 6055 (Dow) is metered in, the exact metering amount being based on the determined NCO content and the OH number of the voranol, stoichiometric amounts being used. The addition takes place within an hour, the temperature being kept at 80.degree. The mixture is then stirred at 80 ° C. under the nitrogen-oxygen atmosphere described above until the isocyanate group content is less than 0.1%. If this value is not reached, an amount of HEMA stoichiometric to the remaining isocyanate content is added, and the reaction is continued until the NCO content is less than 0.1%. 500 ppm of 2-tert-butyl-4,6-dimethylphenol (Aldrich), based on the total mass of the end product, are then added to the product.

The product obtained in this way can be processed without further processing other implementations.

Example 2) Production of polyvalent urethane methacrylate in one one-step synthesis

In a round bottom flask with reflux condenser, thermometer, stirrer and dropping funnel, 0.2 mol ®Voranol CP 6055 (DOW), 0.4 mol hydroxyethyl methacrylate (HEMA), 500 ppm 2,6-di-tert-butyl-4-methylphenol, based on the expected amount of the final product, 0.46 mol of IPDI and 2.10 ^-3 mol of dibutyltin dilaurate (DBTDL) and stirred for one hour at room temperature. The temperature of the mixture is then raised continuously to 80 ° C. within one hour. The temperature is then held at 80 ° C. for about 5 hours until the isocyanate group content has dropped to below 0.1%, a nitrogen-oxygen mixture with about 7% by volume oxygen being present above the mixture located. Residual amounts of isocyanate groups are reacted with a stoichiometric amount of HEMA, provided that the isocyanate content does not decrease to below 0.1% despite an extended post-reaction time. Then 500 ppm of 2-tert-butyl-4,6-dimethylphenol, based on the total mass of the end product, are added to the mixture.

There is a mixture of Obtained urethane methacrylates without further ado Refurbishment can be used in other implementations.

An SEC curve (SEC: size exclusion chromatography) of the product is shown in FIG. 1.

2. Tests - methods 2.1 Production of the plates

The plates were produced by curing a methacrylate resin with the help of dimethyl-p- toluidine (DMPT) or another accelerator amine and dibenzoyl peroxide in a mold Room temperature. The mold consisted of two with Polyester film (Hostaphan film, type RN / 36, 0.036 mm thick, colorless, from Pütz GmbH + Co., 65232 Taunusstein contractions) covered glass plates (25 cm × 22 in cm × 0.4 cm) and an approximately 2 mm thick piping (Vitro tape, type 63020, from Xaver Bayer, 79215 Elzach). The mixture was at least 24 hours hardened.  

2.2 Checking the plates

After 24 hours, test specimens in the form of shoulder bars were punched out of the plates produced in accordance with 2.1. The shoulder bars are shown in Fig. 2. They were 140 mm long and 25 mm wide at the ends, this width remaining constant over a length of 25 mm in order to clamp the test specimen in the test device. The width in the central zone was 6.5 mm. The length of the central zone was 65 mm.

The tests were based on DIN 53455 (1981), which were carried out on 5 test specimens each which was kept in the at least 16 h before the measurement Normal climate according to DIN 50014-23 / 50-2 (1968) stored were. According to the "Technical test regulations for Surface protection systems (TP OS) (The Federal Minister für Verkehr, 1990) the tests were carried out at Room temperature with a test speed of 100 mm / min. The test was carried out at -20 ° C, deviating from the TP OS, at one speed of 50 instead of 10 mm / min.

A universal testing machine was used as the tensile testing machine from Zwick, type 1478.

Example 3

According to the method previously described, a plate was made made that contains a urethane methacrylate, the Preparation is described in Example 2. This was done a mixture of 63 parts by weight of ®Degaroute VP 480 (one in Monomers dissolved on MMA as an essential component based polymer, available from Degussa AG), 1.2% by weight Parts of methyl methacrylate (MMA), 15.6 parts by weight  Butyl acrylate (BA) and 20 parts by weight of urethane methacrylate manufactured. This mixture was 0.2 parts by weight DMPT mixed with 3 parts by weight of dibenzoyl peroxide hardened as previously described.

The plate obtained was prepared according to that described in 2.2 Methods examined. The results for tensile strength and the elongation at break are shown in Table 1.

Example 4)

According to the method previously described, a plate was made made that contains a urethane methacrylate, the Preparation is described in Example 2. This was done a mixture of 63 parts by weight of ®Degaroute VP 480, 6.2 Parts by weight of methyl methacrylate (MMA), 10.6 parts by weight Butyl acrylate (BA) and 20 parts by weight of urethane methacrylate manufactured. This mixture was 0.2 parts by weight DMPT mixed with 3 parts by weight of dibenzoyl peroxide hardened as previously described.

The plate obtained was prepared according to that described in 2.2 Methods examined. The results for tensile strength and the elongation at break are shown in Table 1.

Comparative Example 1)

According to the method previously described, a plate was made made, but no inventive Contains urethane (meth) acrylate. Here, the Resin mixture of Example 3 used, except that 20 parts by weight Parts ®Ebecryl 230 (a divalent urethane (meth) acrylate the company UBC) instead of the invention Urethane (meth) acrylate was used.

The plate obtained was prepared according to that described in 2.2 Methods examined. The results for tensile strength and the elongation at break are shown in Table 1.  

Comparative Example 2)

According to the method previously described, a plate was made made, but no inventive Contains urethane (meth) acrylate. Here, the Resin mixture of Example 4 used, except that 20 parts by weight Parts © Ebecryl 230 instead of the invention Urethane (meth) acrylate was used.

The plate obtained was prepared according to that described in 2.2 Methods examined. The results for tensile strength and the elongation at break are shown in Table 1.

Table 1

Claims (10)

1. Urethane (meth) acrylates with at least 3 reactive terminal ethylenically unsaturated functionalities, obtainable by the reaction of

• 1. Hydroxyalkyl (meth) acrylic acid esters with
• 2. Polyisocyanates and
• 3. Polyoxyalkylenes, the
  • 1. have at least three hydroxy functionalities,
  • 2. wherein the proportion of polyethylene oxide is less than 50 wt .-%, based on the total amount of polyoxyalkylene, or
• 4. Hydroxyalkyl (meth) acrylic acid esters with
• 5. Mixtures of polyisocyanates, of which at least one polyisocyanate has 3 or more isocyanate groups, and
• 6. Polyoxyalkylenes, the
  • 1. have at least two hydroxy functionalities,
  • 2. wherein the proportion of polyethylene oxide is less than 50 wt .-%, based on the total amount of polyoxyalkylene.

2. urethane (meth) acrylates according to claim 1, characterized in that this by the implementation of hydroxyethyl methacrylate, Hydroxyethyl acrylate, hydroxypropyl methacrylate and Hydroxypropyl acrylate and mixtures thereof  Compounds as hydroxyalkyl (meth) acrylic acid esters are available. 3. urethane (meth) acrylates according to claim 1 or claim 2, characterized in that this by reaction of 2,4-toluenediisocyanate, 2,6-toluene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 4,4'-dicyclohexyl diisocyanate, meta- and para-tetramethylxylene diisocyanate, 3-isocyanatomethyl 3,5,5-trimethylcyclohexyl isocyanate (Isophorone diisocyanate), hexamethylene diisocyanate, 1,5-naphthylene diisocyanate, dianisidine diisocyanate, Di (2-isocyanatoethyl) bicyclo [2.2.1] hept-5-ene-2,3- dicarboxylate, 2,2,4- and 2,4,4-trimethylene hexamethylene diisocyanate, triphenylmethane-4, 4 ', 4 "-triisocyanate, Tris (4-isocyanatophenyl) thiophosphate and mixtures of which are available as polyisocyanate. 4. Urethane (meth) acrylates according to one of the preceding Expectations, characterized in that this through the implementation of polyoxypropylene and / or Polytetramethylene oxides, each at least three reactive, terminal hydroxy functionalities have, are available as polyoxyalkylene. 5. Urethane (meth) acrylates according to one of the preceding Expectations, characterized in that this three or four reactive terminal ethylenic have unsaturated functionalities.   6. Urethane (meth) acrylates according to one of the preceding Expectations, characterized in that the polyoxyalkylene a weight average of Molecular weight in the range of 2000 to 20,000 exhibit. 7. A process for the preparation of urethane (meth) acrylates according to at least one of claims 1 to 6, characterized in that

• a) at least one hydroxyalkyl (meth) acrylic acid ester
• b) at least one polyisocyanate and
• c) at least one polyoxyalkylene

implements. 8. The method according to claim 7, characterized in that implementation in the presence of an inhibitor takes place. 9. The method according to claim 7 or 8, characterized in that the reaction in the presence of tertiary amines and / or organic tin compounds, in particular Dibutyltin dilaurate, takes place. 10. Use of urethane (meth) acrylates obtainable after at least one of claims 1 to 6 or producible by at least one method according to claims 7 up to 9 in (meth) acrylate resins for surface protection of flat roofs and traffic areas, especially bridges and parking decks, for the backing of bathtubs or for coatings and seals.