CN1153794C - polyurethane foam - Google Patents

Abstract

The present invention relates to polyurethane foam compositions derived from a reaction mixture comprising a hydrogenated polydiene diol having a number average molecular weight of 1,000 to 20,000, an aromatic polyisocyanate, a plasticizer, and a blowing agent. Preferably, the polyurethane composition further comprises a tackifying resin. The invention further relates to a process for preparing the polyurethane foam and to articles comprising the polyurethane foam.

Description

polyurethane foam

The present invention relates to polyurethane foams, particularly polyurethane foams comprising polyols and aromatic isocyanates having flexibility. The present invention also relates to methods of making polyurethane foams and articles comprising polyurethane foams.

Polyurethane foams with high elasticity are typically made from polyether triols and isocyanates. Polyether triols typically have a number average molecular weight of 4,500 to 6,000 and an average functionality of 2.4 to 2.7 hydroxyl groups per molecule. Utilizing toluene diisocyanate, diphenylmethyl diisocyanate, mixtures of toluene diisocyanate/diphenylmethyl diisocyanate and modified toluene diisocyanate or diphenylmethyl diisocyanate, can be prepared with a wide processing latitude foam plastic. The functionality of the isocyanate is typically 2.0 isocyanate groups per molecule, most often not more than 2.3 isocyanate groups per molecule. Resilient foams can be produced when polyether triols are combined with isocyanates containing 2.0 to 2.3 isocyanate groups per molecule under conditions that promote foam formation.

US Patent 4,939,184 describes the cationic preparation of polyurethanes from polyisobutylene triols and diols. Polyisobutylene is premixed with isocyanate. The so-called isocyanate refers to a mixture of m- and p-toluene diisocyanate with a functionality of 2.0. Water is then added as a blowing agent to form polyurethane foam. The resulting foam has low elasticity and can be used to absorb energy.

International application (PCT) WO 97/00902 describes highly resilient polyurethane foams made from polydiene diols. The elasticity of the foam can be obtained by adding an aromatic polyisocyanate having a functionality of 2.5 to 3.0 isocyanate groups per molecule to ensure sufficient crosslinking. The resulting polydiene glycol foams exhibit superior moisture aging properties compared to conventional polyurethane foams.

US Patent 5,710,192 describes highly elastic, highly tear resistant polyurethane foams made from polydiene diols. By selecting an appropriate amount of aromatic polyisocyanate with a functionality of 1.8 to 2.5 isocyanate groups per molecule to ensure sufficient crosslinking, the elasticity of the foam can be obtained. The polydiene glycol foam thus obtained exhibited excellent tear resistance and was almost white in color.

In the above foams, difficulties have been encountered in processability and in controlling cell size and cell distribution. There is a need to develop a highly processable foam having a small uniform cell size and distribution while maintaining adequate elastic foam properties.

Surprisingly, it has been found that highly processable foams can be obtained by adding plasticizers, such as up to 50%w fat, to polyurethane foams made from polydiene diols. Accordingly, the present invention relates to polyurethane foam compositions derived from reaction mixtures comprising:

Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000;

Aromatic polyisocyanates;

plasticizers; and

Foaming agent.

The foam has a lower viscosity during manufacture and a more uniform cell structure than grease-free foam.

According to a further preferred embodiment, the present invention relates to a polyurethane foam composition derived from a reaction mixture comprising:

Hydrogenated polydiene diols having a number average molecular weight of 1,000 to 20,000;

Aromatic polyisocyanates;

Tackifying resin;

plasticizers; and

Foaming agent.

The plasticizer is preferably compatible with the hydrogenated polydiene diol. If the plasticizer is compatible with the hydrogenated polydiene diol, then after mixing the two components in the preferred weight ratio, the components will not separate into two layers at room temperature for 12 hours.

The plasticizer can typically be selected from plasticizers known to those skilled in the art. Preferably, the plasticizer may be grease and/or hydrogenated diene monoalcohol having a number average molecular weight of 500 to 20,000.

Description of drawings

Figure 1 shows the effect of oil on viscosity.

Figure 2 shows the effect of grease on foam density.

Figure 3 shows the effect of water content on the density of the foams of the present invention.

According to a preferred embodiment, the invention preferably relates to elastic polyurethane foams. The foam comprises 100 parts by weight (pbw) of a hydrogenated polydiene diol having a number average molecular weight of 1,000 to 20,000, more preferably of 1,000 to 10,000, most preferably of 3,000 to 6,000; 20 to 55 pbw of an aromatic polyisocyanate; up to 200 pbw plasticizers, more preferably hydrocarbon processing oils; and blowing agents.

In a preferred embodiment, the hydrogenated polydiene diol has a functionality of 1.6 to 2, preferably 1.8 to 2, hydroxyl groups per molecule. The polyisocyanates used have a functionality of 2.0 to 3.0 isocyanate groups per molecule. The isocyanate is preferably added at a concentration that provides an approximately equal number of isocyanate and hydroxyl groups. Preferably, the NCO:OH molar ratio is from 0.9 to 1.2.

The polydiene diols used in the present invention are typically prepared anionically. Anionic polymerization is well known to those skilled in the art and such methods are described, for example, in US Patent Nos. 5,376,745, 5,391,663, 5,393,843, 5,405,911 and 5,416,168.

The polymerization of polydiene diols begins with a monolithium or dilithium initiator containing protected hydroxyl groups, which polymerizes conjugated diene monomers at each lithium site. Typical conjugated dienes are 1.3-butadiene or isoprene for cost reasons, although other conjugated dienes will work well in the present invention. When the conjugated diene is 1,3-butadiene and the resulting polymer is to be hydrogenated, the anionic polymerization can generally be controlled using a structural modifier to obtain the desired amount of 1,4-addition, said structural modification Aggressive agents such as diethyl ether or 1,2-diethoxyethane.

The anionic polymerization is terminated by adding a functionalizing reagent before the reaction is complete. The functionalizing agents used are well known to those skilled in the art and are described in US Pat. Nos. 5,391,637, 5,393,843 and 5,418,296. A preferred functionalizing agent is ethylene oxide.

To increase stability, the polydiene diol is preferably hydrogenated so that at least 90%, preferably at least 95%, of the carbon-carbon double bonds in the diol are saturated. Hydrogenation of these polymers and copolymers can be carried out by a variety of well-known methods, as described in U.S. Patent No. 5,039,755, in the presence of catalysts such as Raney Nickel®, noble metals (such as platinum), soluble transition metal catalysts, and titanium catalysts. reaction.

Hydrogenated polydiene diols provide stable elastic foams. The polydiene diol preferably has 1.6 to 2, more preferably 1.8 to 2, terminal hydroxyl groups per molecule. For example, an average functionality of 1.8 means that about 80% of the molecules are diols and about 20% of the molecules are -alcohols. Since a large number of product molecules contain two hydroxyl groups, this product can be considered a diol. The polydiene diol of the present invention has a number average molecular weight of 1,000 to 20,000, preferably 1,000 to 10,000, more preferably 3,000 to 6,000. Preference is given to hydrogenated polybutadiene diols, especially polymers of which 40% to 60% are 1,2-additions.

The microstructure of dienes can typically be determined ^by13C nuclear magnetic resonance (NMR) in chloroform. Since after hydrogenation the polymer is a waxy solid at room temperature if it contains less than 40% 1,2-butadiene addition, it is required that the polybutadiene diol have at least 40% 1,2- Addition of butadiene. Preferably, the 1,2-butadiene content is between 40% and 60%. In order to reduce the glass transition temperature ( _Tg ) and viscosity, isoprene polymers typically have at least 80% addition of 1,4-isoprene.

The polydiene diols used in the present invention typically have a hydroxyl equivalent weight of from about 500 to about 10,000, more preferably from 500 to 5,000, most preferably from 1,500 to 3,000. Thus, for polydiene diol, a suitable number average molecular weight is 1,000 to 20,000, more preferably 1,000 to 10,000, most preferably 3,000 to 6,000.

The number average molecular weight of the hydrogenated polydiene diol in the embodiment is 3300, the functionality is 1.92, and the 1,2-butadiene content is 54%. The polymer is hydrogenated, thereby removing greater than 99% of the carbon-carbon double bonds. This polymer is referred to as diol 1 in the following.

The polydiene monools used were obtained essentially by the method for preparing polydiene diols already described herein, except that the polymerization was started with a monolithium initiator. The number average molecular weight of the monohydroxy polydiene polymer is typically 500 to 20,000, preferably 2,000 to 8,000. The number average molecular weight of the hydrogenated polydiene monoalcohol in the embodiment is 3850, the functionality is 0.98, and the 1,2-butadiene content is 48%. The polymer is hydrogenated, thereby removing greater than 99% of the carbon-carbon double bonds. This polymer is referred to as Monool 1 in the following.

The number average molecular weight refers to the number average molecular weight determined by gel permeation chromatography (GPC) calibrated by using polybutadiene standards having known number average molecular weights. The solvent used for GPC analysis was tetrahydrofuran.

The isocyanates used in the present invention are aromatic polyisocyanates which have the desired fast reaction rates for making foams. Since the functionality of saturated polydiene diols is about 2 hydroxyl groups per molecule, polyisocyanates with a functionality of 1.8 to 3.0, preferably 2.5 to 3.0 are typically used to obtain stable, high loading and highly elastic foams The crosslink density of the plastic. The use of isocyanates with low functionality results in less stable foams with lower loading capacity and reduced elasticity. Higher isocyanate functionality can give foams with too high a content of blocked cells, which will have a negative impact on their physical properties.

An example of a suitable aromatic polyisocyanate includes MONDURS MR (Bayer), a polydiphenylmethylisocyanate typically having an isocyanate functionality of 2.7. ^RUBINATE® 9225 (ICI Americas), a liquid isocyanate mixture consisting of 2,4-diphenylmethyl diisocyanate and 4,4-diphenylmethyl diisocyanate, has a functionality of 2.06 ; however, the addition of fats or monoalcohols to foams made from this lower-functionality polyisocyanate can cause the foam to collapse, requiring formulation adjustments.

The fats and oils used in the present invention are petroleum-based processed fats and oils. The composition of these greases can vary within the range of paraffinic-naphthenic-alkane higher aromatics. Usable fats have a wide range of viscosities from 10 to 1000 centipoise at 100°F (38°C). Preferably, the grease used in the form of the present invention includes paraffinic grease, naphthenic grease, or paraffinic/naphthenic grease having the above-mentioned viscosity range. Examples of suitable greases for use in the present invention include SHELLFLEX ^(R) 371 (Shell Grease Company), a paraffinic/naphthenic processing grease having a viscosity of 80-100 centipoise at 100°F (38°C).

Since polydiene diol is a hydrocarbon, it has good compatibility with hydrocarbon processing oils and there is no tendency for the oil to leak out of the foam. Adding fat to the formulation reduces its viscosity and thus improves processability. Figure 1 shows how the viscosity of polydiene diol ( ^Diol 1) blended with grease (SHELLFLEX® 371, SHELLFLEX is a trademark) depends on the amount of grease in the blend. Adding up to 200 parts by weight of grease per 100 parts of polydiene diol resin (phr) will reduce viscosity by a factor of nine at any given temperature. This decrease in viscosity makes the foams of the present invention easier to process than prior foams, resulting in more uniform and finer cell sizes.

Figure 2 shows the effect of grease ( ^SHELLFLEX® 371) concentration on foam density of polydiene diol (diol 1) mixed with polyisocyanate ( ^MONDUR® MR) and water. When the oil content increases from 0 to 200phr, the density will increase by 2 times. Dense foams have finer cells and a very uniform cell size distribution.

The main components of the polyurethane foam of the present invention are polydiene diol, aromatic polyisocyanate, blowing agent (such as water) and plasticizer (preferably grease and/or polydiene monool). Optionally and preferably, the polyurethane foam may further contain a tackifying resin.

The tackifying resins useful in the present invention are relatively low molecular weight, predominantly hydrocarbon polymers characterized primarily by their ring and ball softening points as determined by ASTM standard method E28. Generally, the softening point of the resin is from about 80°C to about 120°C. However, in certain cases, such as for optimum bonding at low temperatures, low softening point resins or liquid resins are advantageous.

As described in U.S. Patent 3,577,398, a typical tackifying resin may be cationic polymerized to contain 60% 1,3-pentadiene, 10% isoprene, 5% cyclopentadiene, 15% 2-methyl-2-butadiene A mixture of alkenes and about 10% dimer was obtained. Commercially available resins of this type include WINGTACK ^(R) 95 (Goodyear Tire & Rubber Company), which has a softening point of 95°C. The resin may also contain some aromatic character which may be introduced by adding styrene or alpha-methylstyrene to the mixture during resin polymerization.

Another class of adhesion promoting resins useful in the present invention includes hydrogenated rosins, rosin esters, polyterpenes, terpene phenolic resins and polymerized mixed olefins. In order to obtain good thermal oxidation properties and color stability, it is preferred to use saturated resins, such as hydrogenated dicyclopentadiene resins, such as ^ESCOREZ® 5000 series (Exxon Chemical Company), or hydrogenated polystyrene resins, such as ^REGALREZ® series (Hercules , Inc.).

When using a tackifying resin with a high softening point, the resin will increase the viscosity of the reaction mixture to the point where foaming will practically not occur. By adding grease, the viscosity during foaming can be reduced and the processability of foamed plastics can be improved. Typical fats and oils used in the present invention include the above-mentioned paraffin/naphthenic rubber processing fats and oils. An example of a grease suitable for use in the present invention is SHELLFLEX ^(R) 371, which has good compatibility with polydiene diol/tackifier mixtures. As such, the grease has no tendency to leak out of the foam and the concentration of the grease is adjusted to obtain the desired viscosity, foam density and tackifying properties.

Foam processability can also be controlled by substituting polydiene monools for part of the polydiene diols. By adjusting the diol to monool ratio, the viscoelastic properties of the foam can be adapted to specific applications. Adhesive foams containing up to 75% by weight of the diol/monool mixture of monool have been found suitable.

The hydrogenated polydiene diol/plasticizer weight ratio is typically at most 5:1, preferably at most 4:1, more preferably at most 3:1, especially at most 2:1. The ratio is typically a minimum of 1:4, preferably a minimum of 1:3, more preferably a minimum of 1:1.5, especially a minimum of 1:1.

The hydrogenated polydiene diol/tackifying resin weight ratio is typically at most 5:1, preferably at most 4:1, more preferably at most 3:1, especially at most 2:1. The ratio is typically a minimum of 1:4, preferably a minimum of 1:3, more preferably a minimum of 1:1.5, especially a minimum of 1:1.

Typically, catalysts and surfactants are required to make foam.

In order to improve the miscibility of ingredients, surfactants are often added, which in turn promotes the hydroxyl/isocyanate reaction. Further, the surface tension of the mixture is reduced, which affects cell nucleation and stabilizes the expanding foam, resulting in a fine cell structure. A preferred surfactant is silicone grease. An example of a suitable commercially available silicone grease is TEGOSTAB-B8404 (TEGOSTAB is a trademark). A preferred silicone surfactant is ^DABCO® DC-5160. Surfactants, if present, are normally added in amounts of 0.01 to 5 parts by weight (0.01-5 phr), preferably 0.01 to 1 phr, per 100 pbw of polydiene diol.

Any catalyst known to be capable of catalyzing one or more blowing reactions in the system can in principle be used. Examples of suitable catalysts are described in European Patent Specification No. 0 358 282 and include amines (such as quaternary amines), carboxylates and organometallic catalysts.

Examples of suitable quaternary amines are triethylenediamine, N-methylmorpholine, N-ethylmorpholine, diethyl-ethanol-amine, N-cocomorpholine, 1-methyl-4-dimethyl- Amino-ethylpiperazine, 3-methoxypropyldimethylamine, N,N,N'-trimethylisopropylpropylenediamine, 3-diethylaminopropyl-diethylamine, dimethyl Benzylamine and Dimethylcyclohexylamine. An example of a carboxylate which can be used as a catalyst is sodium acetate. Examples of commercially available amine catalysts are DABCO ^(R) 33-LV and DANCO ^(R) DC-1 delayed reaction amine catalysts, both available from Air Products and Chemicals. Suitable organometallic catalysts include stannous octoate, stannous oleate, stannous acetate, stannous laurate, lead octoate, lead naphthenate, nickel naphthenate, cobalt naphthenate, and dibutyltin dichloride. Other examples of organometallic compounds useful as catalysts for the preparation of polyurethanes are described in US Patent Specification No. 2,846,408.

The amount of catalyst or catalyst mixture used is generally from 0.01 to 5.0 pbw, preferably from 0.2 to 2.0 pbw, per 100 parts of polydiene diol.

Various blowing agents can be used. Suitable blowing agents include hydrogenated hydrocarbons, aliphatic and cycloaliphatic alkanes, and water, which is often considered a chemical blowing agent. Due to the ozone depleting effects of perchloro, perfluoroalkanes (CFCs), the use of such blowing agents is not preferred, although such blowing agents may be used within the scope of the present invention. Halogenated alkanes in which at least one hydrogen atom has not been replaced by a halogen atom (referred to as HCFCs) have lower ozone depleting efficacy and are therefore preferred halogenated hydrocarbons to be used in mechanically blown foam. A particularly suitable blowing agent of the HCFC type is 1-chloro-1,1-difluoroethane. Particularly preferred blowing agents are hydrofluorocarbons which are considered to have zero ozone depleting efficacy.

It is also known to use water as a (chemical) blowing agent. According to the well-known NCO/H ₂ O reaction, water reacts with isocyanate groups to release carbon dioxide, which produces a foaming effect.

Finally, aliphatic or cycloaliphatic hydrocarbons can be used as CFC selective blowing agents. Examples of such alkanes are n-pentane, isopentane and n-hexane (aliphatic) and cyclopentane and cyclohexane (cycloaliphatic).

It should be understood that the above foaming agents may be used alone or in admixture of two or more thereof. Of all the blowing agents mentioned, we have found that water and cyclopentane are particularly suitable as blowing agents for the purposes of the present invention. Blowing agents are used in those conventional amounts, such as in the case of water, from 0.1 to 5 pbw per 100 parts of polydiene diol; in the case of halogenated hydrocarbons, aliphatic alkanes and alicyclic alkanes , which is used in an amount of about 0.1 to 20 pbw per 100 parts of polydiene diol. A preferred blowing agent is water.

The amount of water added is preferably 0.5 to 3.5 parts by weight per 100 parts of polydiene diol (pbw). The use of distilled or demineralized water is preferred since impurities can adversely affect the foaming reaction.

Flame retardants, fillers and other additives can be added if desired. It is easy for one of ordinary skill in the art to select appropriate amounts of other compounds to add to the composition to be foamed.

In order to further improve the heat and light stability of foamed plastics, antioxidants and UV light stabilizers can be added. Hindered phenolic antioxidants, such as ^IRGANOX® 1076 (Ciba Geigy), are very suitable for stabilizing these foams. A combination of a UV absorber such as ^TINUVIN® 328 (Ciba Geigy) and a hindered amine light stabilizer such as TINUVIN® ¹²³ (Ciba Geigy) can preferably be used for optimum resistance to solar degradation.

Polyurethane foam is preferably made by mixing all ingredients except polyisocyanate. To reduce the viscosity prior to mixing, the polydiene diol and (if present) polydiene monool are preheated (typically to about 80°C). The tackifying resin is preferably preheated (typically to about 150°C). After mixing, the aromatic polyisocyanate is added quickly, stirring briefly before pouring the mixture into molds holding expanded foam.

Therefore, another aspect of the present invention relates to a method for preparing a polyurethane foam composition, the method comprising:

(i) mixing hydrogenated polydiene diol having a number average molecular weight of 1,000 to 20,000 with plasticizer, blowing agent and optionally tackifying resin, surfactant and catalyst to obtain a mixture;

(ii) combining an aromatic polyisocyanate with the mixture to obtain a composition, and

(iii) foaming the composition to obtain a polyurethane foam composition.

Polyurethane foam can be cured by heating the foam to an elevated temperature (usually 100 to 160°C) for a period of time (typically 10 minutes to 96 hours, preferably 30 minutes to 48 hours). Generally, however, the heat generated during the exothermic reaction to form the polyurethane is sufficient to insure complete cure, which can be carried out adiabatically.

A preferred embodiment of the present invention relates to elastic polyurethane foam comprising 100 parts by weight of hydrogenated polydiene diol having a number average molecular weight of 3,000 to 6,000 and a functionality of 1.8 to 2.0 hydroxyl groups per molecule, 0.5 to 3.5 Parts by weight of water, aromatic polyisocyanate having a functionality of 2.5 to 3.0 isocyanate groups per molecule and a concentration such that almost equal amounts of isocyanate and hydroxyl groups are obtained, 20 to 200 parts by weight of oil, 0.4 to 0.8 parts by weight of amine catalyst, 0.3 to 0.6 parts by weight of delayed action amine catalyst and 0 to 0.06 parts by weight of silicon surfactant. The foams of the present invention exhibit superior cell sizes and cell size distributions compared to foams prepared in the absence of grease.

Another preferred embodiment of the present invention relates to elastic polyurethane foams comprising 100 parts by weight of hydrogenated polydiene diols having a number average molecular weight of 3,000 to 6,000 and a functionality of 1.8 to 2.0 hydroxyl groups per molecule, 0.5 to 2.0 3.5 parts by weight of water, an aromatic polyisocyanate having a functionality of 2.5 to 3.0 isocyanate groups per molecule and a concentration such that approximately equal numbers of isocyanates and hydroxyl groups are obtained, 50 to 150 parts by weight of a tackifying resin, 10 to 100 parts by weight of grease, 0.4 to 0.8 parts by weight of amine catalysts, 0.3 to 0.6 parts by weight of delayed action amine catalysts and 0 to 0.06 parts by weight of silicon surfactants.

Yet another preferred embodiment of the present invention relates to elastic polyurethane foams comprising 25 to 100 parts by weight of hydrogenated polydiene diols having a number average molecular weight of 3,000 to 6,000 and a functionality of 1.8 to 2.0 hydroxyl groups per molecule, 75 to 0 parts by weight of a polydiene monool having a number average molecular weight of 2000 to 4000, 0.5 to 3.5 parts by weight of water, a functionality of 2.5 to 3.0 isocyanate groups per molecule and a concentration such that an almost equal amount of isocyanate is obtained and hydroxyl aromatic polyisocyanate, 50 to 150 parts by weight of tackifying resin, 0 to 100 parts by weight of grease, 0.4 to 0.8 parts by weight of amine catalyst, 0.3 to 0.6 parts by weight of delayed action amine catalyst and 0 to 0.06 parts by weight parts of silicone surfactants.

The invention also relates to articles comprising the polyurethane foams according to the invention.

While each example may support each patentable claim, the examples described below are not meant to limit the invention to specific embodiments.

Example 1

Eight kinds of foamed plastics were prepared using polymer, isocyanate ( ^MONDUR® MR), catalyst ( ^DABCO® 33-LV and DABCO® DC-1), surfactant ( ^DABCO® DC-5160) and water in the combination shown ⁱⁿ Table 1 . Samples 2-7 also contained hydrocarbon processing grease (SHELLFLEX ^(R) 371), which are samples illustrating the invention. Sample 1 is a comparative example which does not contain grease. Sample 8 is another comparative example which contains grease but utilizes conventional polyether polyol.

In a typical preparation, the polymer and grease are preheated to 80°C. All ingredients, except the isocyanate, were weighed into a dry container and mixed using a CAFRAMO ^(R) mixer fitted with a 2-inch (5.1 cm) equal pitch impeller. The isocyanate was then added and mixing continued for approximately 45 seconds. At this point most of the substance starts to foam and it is poured into paper drums. After the foam had stabilized and formed a film, the foam was baked in an oven at 110° C. for 10 minutes. Samples were cut from the loaves and their foam density, hardness at 40% compression, elasticity and hysteresis were determined.

density

The density of the foam was determined by the weight and volume of the foam block. The results are shown in Table 2.

elasticity

A steel ball (16.3 g) with a diameter of 16 mm is dropped from a height of 51.6 cm into a 10×10×5 cm foam block through a transparent plastic tube with an inner diameter of 38 mm. Measure the rebound height, and calculate the elasticity according to the following formula: 100×(rebound height/falling ball height). The results are shown in Table 2.

Compression hardness and hysteresis loss

Compression hardness and hysteresis loss were measured on an ^INSTRON® Machine Model 5565. A foam block measuring 10 x 10 x 5 cm was placed between two parallel plates, compressed 60%, then unloaded and cycled four times at a right angle extrusion speed of 12.5 cm/min. During the fourth cycle, the force used to compress the foam by 40% was recorded, resulting in a measurement of the compression hardness of the foam. Hysteresis loss is obtained by calculating the area under the stress/height curve for the fourth cycle relative to the first cycle. The results are shown in Table 2.

Table 1. Foam formulations sample Diol ¹ (phr) oil (phr) water (phr) Isocyanate (phr) Amine catalyst (phr) Delayed Action Amine Catalysts (phr) Surfactant (phr) 12345678 100100100100100100100100 011.133.3100200200200100 11111231 23.523.523.523.522.137.051.823.5 0.40.40.40.40.40.40.80.4 0.30.30.30.30.30.30.60.3 0.020.020.020.020.020.020.040.02

¹ Sample 1-7 uses hydrogenated polybutadiene diol, Mn=3300, f=1.92; Sample 8 uses polyether triol ( ^ARCOL® 11-34) with a molecular weight of 4800

Table 2. Foam Properties sample Density (g/l) Compression 40% hardness (N) elasticity(%) Hysteresis loss (%) Cell Size Distribution foam cell structure ^12345678a 109124135202339267163--- 27.831.023.520.8------9.6--- 5054565032503615 14131613------8--- wide wide narrow very narrow very narrow very narrow very narrow--- Very thin very thin very thin very thin very thin medium

^aStyrofoam is very oily and exhibits poor strength

Samples 1-5 are similar formulations, and the fat content is increased from sample 1 (no fat) to sample 5 (200phr fat). Samples 1-5 all contained 1 phr of water, so they all foamed to the same volume, about 9 times each. The density appears to increase as the amount of fat added increases to this volume. From the results obtained it can be seen that the addition of 11 phr grease (sample 2) has essentially no effect on the properties and qualitative appearance of the foam. Addition of 33 phr grease (sample 3) reduces the cell size distribution with only a small effect on density. Adding 100 to 200 phr of grease (samples 4 and 5) will give a foam with a very uniform distribution of small cell sizes, but a heavy foam. No grease was observed to leak from any foam.

Samples 5-7 and Figure 3 show the effect of increasing water content in foams containing 200 phr grease. Higher amounts of water lead to an increase in isocyanate content and thus more foaming, resulting in a decrease in the density of the foam. It is believed that a foam containing 200 phr of grease can achieve a density of 110 g/l with about 4 phr of water, which is comparable to the density of Sample 1 without grease. However, foams with high fat content have lower compressive hardness and cohesive strength than non-grease foams of the same density.

Sample 8 is a conventional foam based on polyether polyol to which grease has been added. These conventional types of foam are not suitable for adding grease. Grease was felt and leaked in these foams due to the incompatibility of the grease with the polyether polymer.

Example 2

Using diol 1 or diol 1/monol 1 mixture, isocyanate ( ^MONDUR® MR), tackifying resin (WINGTACK95), catalyst ( ^DABCO® 33-LV and ^DABCO® DC-1), surfactant ( ^DABCO® DC-5160) and water to prepare 5 kinds of foamed plastics through the combinations shown in Table 3. Both foams contained hydrocarbon processing grease ( ^SHELLFLEX® 371).

In a typical preparation, the diol, monool and grease (if present) are preheated to 80°C and the tackifying resin is preheated to 150°C. The procedure in Example 1 was then used.

Density, elasticity, compressive hardness and hysteresis loss were measured according to the method of Example 1, and the results are shown in Table 4.

Table 3. Foam formulations sample Diol ¹ (phr) Monool ² (phr) Grease (phr) Resin (phr) water (phr) Isocyanate (phr) Amine catalyst (phr) Delayed Action Amine Catalysts (phr) Surfactant (phr) 1910111213 100100100505025 000505075 010050000 0821001005050 12331.51.5 23.537.051.849.827.626.6 0.40.80.80.80.40.4 0.30.60.60.60.30.3 0.020.040.040.040.020.02

¹ hydrogenated polybutadiene diol, Mn=3300, f=1.92

² Hydrogenated polybutadiene monoalcohol, Mn=3800, f=0.98

Table 4. Foam Properties sample Density (g/l) Compression 40% hardness (N) elasticity(%) Hysteresis loss (%) foam cell structure 1910111213 109122111------109 27.85.36.6------0.0 501010------0 143269------96 Very thin, very thin, no growth, collapse, very thin

Sample 1 is a high resilience foam example for comparison purposes. When the density is 109g/l, the compressive hardness is 28N, it has good elasticity and low hysteresis loss. But since it contains no resin, it has no sticky or adhesive characteristics. Samples 9 and 10 examine the effect of adding tackifying resins and grease, adjusting the water content, to obtain foams with approximately constant densities. The results show that these foams are easier to compress, less elastic, and have higher hysteresis losses than Sample 1, as required for pressure sensitive adhesives. Foam Samples 9 and 10 are both very good pressure sensitive adhesives, both have good nail tack, both adhere well to paper, and can coat surfaces. Both also released cleanly from the substrate, providing examples of adhesive foam removal. Samples 11-13 show the effect of using a grease-free polydiene diol/polydiene monool blend. Samples 11 and 12 did not yield satisfactory foams. However, it is believed that satisfactory foams can be obtained with both formulations by adjusting the preheat temperature, mixing program and catalyst concentration. Sample 13 was fine, a very soft and sticky foam. Sample 13 is an unusual type of foam in that it does not spring back immediately after compression, but fully returns to its original shape and size after standing. Since after the first compression, the foam recovered little in the short time period of the test, the compression hardness was zero and the hysteresis loss was close to 100%. In the elasticity test, the foam only loses the energy of the falling weight without any rebound.

While the present invention has been described in detail for purposes of illustration, such detailed description is not intended to limit the invention, but is intended to cover all changes and improved modes without departing from the spirit and scope of the invention.

Claims (7)

1. polyurethane foam compositions of deriving and obtaining by the reaction mixture that comprises following compositions:

Number-average molecular weight is that 1,000 to 20,000 functionality is the hydrogenation polydiene glycol of 1.6～2 hydroxyls of per molecule;

Functionality is the aromatic polyisocyanate of 1.8～3.0 isocyanate group of per molecule;

Softening agent;

Whipping agent; With

Tackifier,

Wherein softening agent is that grease and/or number-average molecular weight are 500 to 20,000 hydrogenation polydiene, one alcohol and wherein the polydiene glycol be 5: 1 to 1: 4 with respect to the amount of softening agent, the polydiene glycol is 5: 1 to 1: 4 with respect to the amount of tackifying resin, and the amount of the how different poly-acid esters of described aromatics is 20-55 weight part/100 part hydrogenation polydiene glycol.

2. the polyurethane foam compositions of a claim 1 that obtains by the method that comprises the steps:

Hydrogenation polydiene glycol and aromatic polyisocyanate, whipping agent and softening agent are merged; With

The polydiene glycol, aromatic polyisocyanate, whipping agent and the softening agent that allow to merge foam, and obtain polyurethane foam compositions.

3. according to the polyurethane foam compositions of claim 2, wherein hydrogenation polydiene glycol, whipping agent, softening agent and any other composition with mix before aromatic polyisocyanate merges.

4. according to the polyurethane foam compositions of claim 2 or 3, wherein use tensio-active agent and catalyzer.

5. according to each polyurethane foam compositions among the claim 2-4, wherein also comprise tackifying resin.

6. method for preparing polyurethane foam compositions, comprising:

(i) with number-average molecular weight be 1,000 to 20,000, functionality is hydrogenation polydiene glycol and softening agent, the whipping agent of 1.6～2 hydroxyls of per molecule and looks tackifying resin, tensio-active agent and the catalyst mix that particular case exists, and obtains mixture;

(ii) be with functionality the aromatic polyisocyanate of 1.8～3 isocyanate group of per molecule and mixture merge and

(iii) with its foaming, obtain polyurethane foam compositions, wherein softening agent is that grease and/or number-average molecular weight are 500 to 20,000 hydrogenation polydiene one alcohol.

7. the goods that comprise each polyurethane foam compositions among the claim 1-5.

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