MXPA96004853A - Polyurethane articles, molded by the reacc structural injection molding process - Google Patents

Abstract

The present invention provides polyurethane components and compositions capable of providing internal mold release properties in reaction injection structural molding ("SRIM") applications. The polyol composition of the invention has an isocyanate reactive polyol (A), having an average molecular weight, in number, of from 100 to about 10,000, and an effective amount of the internal mold release composition (B), which it has a polymer (a) containing silicon and at least one diester functional compound (b), which is the reaction product of (i) an aromatic carboxylic acid and (ii) alcohols having 2 to 30 carbon atoms. The invention further provides a SRIM polyurethane composition, useful in the preparation of molded polyurethane articles, having internal mold release properties, the composition comprising an isocyanate component (I) and the isocyanate reactive polyol composition (component (II)), described above. In another aspect of the invention, this invention provides methods for using the claimed compositions, as well as polyurethane, cellular and rigid SRIm articles, which are produced from such processes.

Description

POLYURETHANE ARTICLES, MOLDED BY THE PROCESS OF REACTION STRUCTURAL INJECTION MOLDING 1. BACKGROUND OF THE INVENTION The present invention relates to molded, cellular polyurethane articles having internal mold release capabilities, to the compositions used in the preparation of these articles and to methods for obtaining such articles. More particularly, the invention relates to polyurethane articles, rigid, cellular, molded, produced by reaction injection structural molding processes ("SRIM"). The molded articles of the invention can be characterized by their densities ranging from 240 to 640 kg / m3. More particularly, the invention relates to rigid, cellular, SRIM polyurethane articles having glass fiber reinforcements, these articles having internal mold release capabilities. Molded polyurethane articles, cellular and non-cellular, have found many applications in the automotive and construction industries. Illustrative applications in automobiles include the use of such items as consoles, door panels, pillars and seat backs. Examples of uses not in automobiles include supports and doors in residences and showers.

Although many polyurethane molded parts are produced by reaction injection molding ("RIM") processes, it has been found that the use of fiber reinforcements, both woven and non-woven, can supply parts with higher tensile strength and modulus. of flexion. These processes are known as structural reaction injection molding ("SRIM"). The SRIM processes can generally be described as emptying or injecting a liquid foam composition into a closed or open mold, which, when open, subsequently closes during the forming reaction. Prior to pouring the liquid foam composition, reinforcing glass fiber mats and / or other plastic reinforcement parts are placed in the open mold. In some cases, a cosmetic liner or cover material can initially be deposited in the open mold, before placing the reinforcing materials and / or the liquid foam composition. When these cover materials are used and the liquid foam composition is subsequently emptied into the partially filled mold, the process is known as the post-fill process or SRIM process of casting delay. Although the SRIM molding processes face unique problems to their particular processes, they also have problems related to any conventional polyurethane molding process. In any molding operation, considerations of efficiency and cost determine that the length of time required to obtain each piece is reduced to the minimum as much as possible. As a result, it is highly desirable that each piece be removed from the mold as quickly and easily as possible. However, those skilled in the art will appreciate that molded polyurethane parts often resist mold release. Traditionally, external mold release agents ("EMR") have been applied on the surface of the mold, each time a new part is to be molded. The use of these EMR agents is highly disadvantageous for two reasons. First, the use of EMR agents adds significantly to the cost per piece. Factors, such as the cost of the EMR agent per application, the cost of labor or the equipment required to apply the EMR agent. and the cost of the time during which the mold will be, but not in function, should all be included when evaluating the additional cost per piece, which results from the use of the EMR agents. Second, EMR agents often include volatile components, which result in the need for air cleaning and / or ventilation equipment. Fans, blowers and protective gears, all represent a significant investment of capital. As a result, polyurethane formers have long desired internal mold release agents ("IMR"), which are mixed with one or more of the polyurethane components and are thus present during each molding cycle. These internal mold release agents are attempted to appear at the interface, between the mold wall cavity and the reaction ingredients, to cause sufficient non-adhesion between the two, so that release and removal of the molded article can be easily achieved. . Examples of previous attempts of the prior art to supply IMR agents are disclosed in several US patents. Illustrative is US Patent No. 4,111,861, which discloses compositions and methods for forming polyether polyurethanes using internal mold release additives, selected from four classes described, namely: (1) mixtures of aliphatic or aryl carboxylic acids and a polar metal compound, (2) carboxyalkyl-silanes, (3) aliphatic glyoximes and (4) ammonium salts Quaternary aralkyl. U.S. Patent No. 3,875,069 discloses lubricating compositions useful in the configuration of thermoplastic materials, comprising a mixture of: (A) mixed esters of aliphatic polyols, dicarboxylic acids and long chain aliphatic monocarboxylic acids and (B) two-phase esters groups: (1) esters of dicarboxylic acids and long chain aliphatic monohydric alcohols, (2) esters of long chain aliphatic monocarboxylic acids, (3) esters, complete or partial, of aliphatic polyols and long chain aliphatic monocarboxylic acids, in a ratio of (A) to (B) from 1: 3 to 9: 1. The patents of E. U. A., Nos. 4,052,495 and 4,457,887, assigned to Dow Corning Corporation, disclose, respectively, siloxane-polyoxyalkylene copolymers and silicones, intended for use as internal mold release agents in the molding of poly-urethane articles. Similarly, the patents of E. U. A., Nos. 4,498,929, 4,546,145, 4,504,314 and 4,447,366, assigned to ICI, disclose internal mold release agents, which incorporate particular polysiloxane compounds. However, very few attempts of the prior art in the provision of internal mold release agents have been successfully directed towards the applications of the SRIM. The process of molding articles by the SRIM provides unique challenges to the successful incorporation of IMR agents. The use of these IMR agents should not interfere with or impair the internal adhesion of the polyurethane composition to internal components similar to glass fiber mats and / or structural reinforcement elements based on polymers. Similarly, the IMR agent on the exterior surface of the finished SRIM article should not interfere with adhesion between the article and external components, such as the cover material used in SRIM applications with casting delay. Finally, the use of the IMR agents should not interfere with the flow characteristics or the reactivity profile of the polyurethane composition. Those skilled in the art will appreciate that the polyurethane compositions used in SRIM applications must exhibit superior flowability and, generally, low viscosity, in order to accommodate the stress of reinforcing materials. In addition to the performance requirements of the SRIM finished article, those skilled in the art will appreciate that it would be highly desirable to achieve polyol compositions capable of delivering the internal release properties of the mold, which exhibit minimal separation behavior upon standing. It will also be appreciated by those skilled in the art that IMR agents will often exhibit the separation behavior, when combined in either the polyol component or the isocyanate component of a polyurethane composition. Such separation behavior represents special challenges of the process and often requires the use of a costly process and / or mixing equipment. It is thus an object of the invention to provide an internal mold release agent, which is capable of being used in SRIM compositions and applications and which reduces the need to apply EMR agents. It is a further object of the invention to provide a polyol composition having an internal mold release agent, which exhibits minimal separation behavior and which, when used in SRIM applications, supplies rigid, cellular polyurethane articles. , that exhibit good adhesion to both internal and external components. It is a further object of the present invention to provide a foam composition for the preparation of molded polyurethane articles, having internal mold release properties, in which the polyol component of the composition exhibits little or no separation behavior and The composition produces rigid, cellular polyurethane articles that exhibit good adhesion to both internal and external component elements. Finally, it is an object of the invention to provide improved methods for obtaining the SRIM articles, wherein these articles have internal mold release properties and the need to apply EMR agents is reduced. 2. SUMMARY OF THE INVENTION These objects and others are satisfied with the compositions of the invention. The internal mold release composition and the polyol composition of the invention are capable of providing internal mold release properties to a SRIM polyurethane system and reduce the need for EMR agents. The internal mold release composition of the invention includes a polymer (a) containing silicon and at least one functional diester compound (b), which is the reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols with 2 to 30 carbon atoms. The polyol composition of the invention requires an isocyanate reactive polyol (A), having a molecular weight of 100 to about 10,000, and an effective amount of an internal mold release composition (B), which has a polymer (a ) containing silicon and at least one diester functional compound (b), which is the reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols having 2 to 30 carbon atoms. The invention further provides a composition useful in the preparation of molded polyurethane articles, having internal mold release properties, the composition comprising an isocyanate component (I) and an isocyanate reactive polyol component (II), which requires an isocyanate reagent polyol (A), with a molecular weight of 100 to about 10,000, and an effective amount of an internal mold release composition (B), which requires a silicon-containing polymer (a) and at least one diester functional compound (b), which is the reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols having from 2 to 30 carbon atoms. It has been found that the use of the polyol component and the polyurethane composition, as described herein, provide several advantages. Significant improvements in productivity and a decrease in overall cycle time have been made. More particularly, times have been set for the demolding of SRIM articles that are less than one minute and, in some cases, less than 50 seconds. In addition, it has been found that smaller or greatly reduced amounts of the external mold release agent are required. Finally, the molds appear to be easier to clean, when the compositions of the invention are used. The invention also provides methods for using the disclosed polyol and polyurethane compositions, as well as articles produced by such methods. In particular, the invention provides a process for obtaining a molded polyurethane article, which has internal mold release properties, this method requires the provision of a mold; placing within the mold a composition comprising an isocyanate component (I) and an isocyanate reactive polyol component (II), this component (II) requires an iso-cyanate reactive polyol (A), which has a molecular weight of 100 to about 10,000, as well as an effective amount of an internal mold release composition (B), this composition (B) has a polymer (a) containing silicon and at least one functional diester compound (b), the reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols having from 2 to 30 carbon atoms; and allowing the composition to react within the mold, for a sufficient time, to produce a molded polyurethane article having internal mold release properties. Finally, the invention provides a method for obtaining a molded composite article, this method requires placing a cover material inside a mold of the composite article; Subsequently placing within the mold of the composite article an SRIM molded polyurethane article, which has internal mold release properties, this SRIM article is produced by a process that requires supplying an SRIM article mold, placing, inside the mold of the SRIM article, a composition having an isocyanate component (I), and an isocyanate reactive polyol component (II), this component (II) has an isocyanate reactive polyol (A) and an effective amount of an internal composition (B) mold release, this composition (B) has a polymer (a) containing silicon and at least one diester functional compound (b), which the reaction product of (i) an aromatic dicarboxylic acid e ( ii) alcohols having from 2 to 30 carbon atoms, allowing the composition to react within the mold of the SRIM article for a sufficient time to produce an SRIM molded polyurethane article, which that it has internal mold release properties, and remove the item from the mold of the SRIM article; supplying within the mold of the composite article, a polyurethane foam composition; and allowing this polyurethane foam composition to react within the mold of the co-positioned article, for a sufficient time to produce a composite molded article. 3. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The polyurethane composition of the invention requires an isocyanate component (I) and an isocyanate reactive polyol component (II). This isocyanate reactive polyol component (II) must have, at a minimum, an isocyanate reactive polyol (A) having a molecular weight of from 100 to about 10,000 and an effective amount of an internal composition (B) of mold release. .

This internal mold release composition (B) requires a polymer (a) containing silicon and at least one functional diester compound (b), which is the reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols having from 2 to 30 carbon atoms. It has been found that the combination of components (a) and (b) exhibits synergism and provides unexpectedly advantageous internal mold release properties to the SRIM articles and to the molding processes. The particular combination of (a) and (b), in the revealed proportions, provides advantageous results of the release, compared to the performance of (a) and (b) alone. The silicon-containing polymer (a) will generally be a silicone, i.e. a polymer containing the part of -Si (R2? - The silicon-containing polymer (a), preferably used in the invention, includes two or more secondary groups of hydroxyl, and preferably an average of three hydroxyl groups per molecule of the silicon-containing polymer In a particularly preferred aspect of the invention, the silicon-containing polymer is a dimethylsiloxane compound, which is represented by the following generic formula: Rn-H wherein each R is, independently, an alkyl radical having from 1 to 20 carbon atoms; an alicyclic, aryl, alkaryl or aralkyl group, having from 1 to 25 carbon atoms in the alkyl group; a group of aliphatic ether; or a polyester group; and wherein a secondary hydroxyl functional group is substituted in at least two, preferably in each of the R groups; each of A is, independently, one or more silicon atoms, containing alkyl, alicyclic, cycloalkyl, aryl, alkyloxy, alkaryl, aralkyl or aryl-alkoxy groups, having 1 to 25 carbon atoms in each aliphatic portion; an organosiloxane; hydrogen; or an alkyl group having 1 to 25 carbon atoms; n is an integer from 1 to 10; and the sum of w + x + y + z is equal to an integer corresponding to an average hydroxyl equivalent weight in the range of 200 to 4,000.

Preferably, each R is, independently, an alkyl group having from 1 to 10 carbon atoms, an alkoxy group or an ether having the formula: and preferably A is hydrogen, a C 1 -C 4 alkyl group or a siloxane, having the formula: where n is an integer from 1 to 6, and the sum of w + x + y + z is equal to an integer corresponding to an average hydroxyl equivalent weight of the molecule, which varies from 1,250 to 3,000. In the most preferred embodiment of the invention, the silicon-containing polymer (a) used in the invention will be the Dow Corning® 1248 fluid sold by Air Products of Allentown PA or any commercially available equivalent. An equivalent, commercially available is believed to be DABCO®2 DC5000. The fluid 1248 has an average of 3 hydroxyl sites per molecule and an average hydroxyl equivalent weight of about 1,725 to 2,225, and more likely about 2,000. It is believed that this fluid corresponds to the formula: in which each n is, independently, an integer that varies from 1 to 4, and where the sum of w + x + y + z is approximately 70, or corresponds to an average weight of the equivalent of 1 Dow Corning is a registered trademark of Dow Corning Corporation. 2 DABCO is a registered trademark of Air Products Corporation. hydroxyl of a molecule of approximately 2,000. Methods for the manufacture of such silicon-containing polymers are generally described in the U. A., No. 4,130,708, the description of which is incorporated herein by reference. The second component of the internal mold release composition, according to the invention, is at least one functional diester compound (b), which is a reaction product of (i) an aromatic dicarboxylic acid and (ii) alcohols having from 2 to 30 carbon atoms. The aromatic dicarboxylic acids (i) will generally have between 8 and 14 carbon atoms. These aromatic dicarboxylic acids can be mononuclear or polynuclear. Examples of suitable mononuclear aromatic dicarboxylic acids are phthalic acid, terephthalic acid and isophthalic acid. Examples of suitable polynuclear aromatic dicarboxylic acids include naphthalic acid and diphenyl-or, or • -dicarboxylic acid. Mononuclear aromatic dicarboxylic acids are preferred. Especially preferred is phthalic acid. The second reagent used in obtaining at least one diester functional compound (b) is an alcohol (ii) having from 2 to 30 carbon atoms. A wide variety of alcohols are suitable for use in producing the compound (b). Preferred alcohols are the monofunctional aliphatic alcohols. The alcohols can be linear, branched or even highly branched oxo alcohols. The linear alcohols are the most suitable. Monofunctional aliphatic alcohols having from 2 to 30 carbon atoms are preferred. More preferred are aliphatic monofunctional alcohols having from 4 to 15 carbon atoms. Especially preferred, the mono-function alcohols ^! is aliphatic (i) will have 8 to 11 carbon atoms. Examples of suitable monofunctional aliphatic alcohols include ambutyl alcohol, isobutyl alcohol, isohexyl alcohol, 1,3'-dimethylbutyl alcohol, heptyl alcohol, octyl alcohol, 2-ethylhexyl alcohol, isooctyl alcohol, alcohol oxo, dodecyl alcohol, undecyl alcohol, tridecyl alcohol, isotridecyl alcohol, tetradecyl alcohol, hexadecyl alcohol, isohexyldecyl alcohol, styrene alcohol and behenyl alcohol, alcohols of 12 to 30 carbon atoms, such as oleyl alcohol, as well as mixtures of alcohols which are obtained by the hydrogenation of fatty acid mixtures of 12 to 30 carbon atoms, derived from natural fats and oils, such as olive oil, grape seed oil, oil coconut, palm oil, soybean oil, cottonseed oil and linseed oil. The alcohols (i) used to react with the aromatic dicarboxylic acid (i) can be a suitable simple alcohol or can be a mixture of 2 or more suitable alcohols. It will be appreciated that the use of a single suitable alcohol will result in the formation of diesters (b) having the structure (R'OOCRCOOR11), where R is an aromatic structure and R 'and R "are identical. suitable alcohols will produce compounds (b) having the structure (R'OOCRCOOR "), wherein R is an aromatic structure and R 'and R" are not identical, While it is possible to use mixtures of several monofunctional alcohols, it is more preferred that it uses only one alcohol, so that diesters of identical structure are formed, ie R'OORCOOR 'However, it is within the scope of the invention to use esters (b) where R' and R "are different. Particularly preferred reagents for use in obtaining at least one diester functional compound (b) are phthalic acid and undecyl alcohol. Therefore, the at least one functional diester compound (b) is particularly preferred is di-undecyl phthalate or DUP. Reagents (i) and (ii) will generally react in a manner known to those skilled in the art. That is, the production of at least one diester functional compound (b) is carried out according to known methods of esterification, for example, the esterification of the hydroxyl groups of the alcohols (ii) with the aromatic dicarboxylic acids (i) for produce complete esterification. In general, one mole of the dicarboxylic acid (i) will react with two moles of the monofunctional alcohols, (ii). As indicated above, it has unexpectedly been found that the combination of (a) and (b) provides unexpectedly advantageous internal mold release properties. As a result, at a minimum, the internal mold release composition (B) will have from 1 to 99 parts by weight of the polymer (a) containing silicon and from 99 to 1 part by weight of the compound (b), all the parts by weight are based on the total weight of the internal composition (B) of mold release. More particularly, it has been found that good internal mold release properties are obtained when the IMR composition (B) contains from 1 to 50 parts by weight of the silicon-containing polymer (a) and from 50 to 99 parts by weight of this at least one diester functional compound (b). Optimal internal mold release properties have been achieved when this internal mold release composition (B) contains from 1 to 15 parts by weight of polymer (a) containing silicon and from 85 to 99 parts by weight of compound (b) . In general, the polyol composition (II) of the invention (also known as the resin part or the polyol component) should contain about 10 to 60 weight percent of the internal mold release composition (B), based on the total weight of the polyol composition. That is, 100 kilograms of a polyol composition, comprised of a mixture of isocyanate reactive polyol (A) and internal mold release composition (B), of 10 to 60 kilograms must be of the composition (B) of IMR, while 90 to 40 kilograms are polyol (A) isocyanate reagent. Those skilled in the art will appreciate that increasing amounts of the internal mold release composition (B) will provide the best release properties, while increasing amounts of the isocyanate reactive polyol (A) will generally provide the best overall performance properties in SRIM polyurethane articles, molded, finished. It has been found that, ideally, the internal mold release composition (B) will be present in a weight ratio of about 1 part of the IMR agent (B) to 2 parts of the polyol (A). That is, in a total of 99 parts by weight of the polyol composition of the invention (ie, the component (II) of polyol), 33 parts by weight will be of the internal composition (B) of mold release, while 66 parts will be comprised of the polyol (A) isocyanate reagent.

Examples of suitable polyols (A) isocyanate reagents are the compounds having at least two isocyanate reactive hydrogens, which are intended to be used in the preparation of polyurethane foams and elastomers. These compounds are often prepared by the catalytic condensation of an alkylene oxide or mixtures of alkylene oxides, or simultaneously or in sequence, with the organic compound having at least two active hydrogen atoms, as is evident from the patents of USA, Nos. 1,922,459, 3,190,927 and 3,346,447. Representative polyols include the polyoxyester and polycarbonate containing polyhydroxyl, polyoxyalkylene polyether polyols, such as the aforementioned polyoxyalkylene polyether polyols, poly-hydroxy terminated polyurethane polymers, polyhydroxy containing phosphorus compounds and alkylene oxide adducts of polyhydric polythioethers, polyacetals, polyols and aliphatic thiols, ammonia, and amines, which include the aromatic, aliphatic and heterocyclic amines, as well as their mixtures. Alkylene oxide adducts of the compounds containing two or more different groups, within the classes defined above, can also be used, for example, amino alcohols containing an amino group and a hydroxyl group. Similarly, alkylene oxide adducts of compounds containing an SH group and an OH group, as well as those containing amino groups and an SH group, can be used. In general, the number average molecular weight of polyols will vary from more than 400 to 10,000. However, it has been found that nitrogen-containing molecules, particularly those with amino groups, are preferred initiators. Suitable hydroxyl-terminated polyesters can be used, such as those prepared, for example, from polycarboxylic acids and from polyhydric alcohols. Any suitable polycarboxylic acid can be used, such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, brasilic acid, tapsic acid, maleic acid, fumaric acid, glutaconic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethyl-glutaric acid, α, β-diethyl-succinic acid, isophthalic acid, terephthalic acid, hemimelitic acid and 1,4-cyclohexanedicarboxylic acid. Any suitable polyhydric alcohol can be used, including both aliphatic and aromatic, such as ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, glycerol, 1,1-trimethylolpropane, 1,1-trimethylolethane, 1,2,6-hexanetriol, α-methyl glucoside, pentaerythritol and sorbitol. Also included within the term "polyhydric alcohols" are phenol-derived compounds, such as 2,2-bis (4-hydroxyl-phenyl) propane, commonly known as Bisphenol A. The hydroxyl-containing polyester can also be an amide of polyester, as obtained by the inclusion of an amine or an amino alcohol in the reagents, for the preparation of the polyesters. Thus, the polyester amides can be obtained by condensing an amino alcohol, such as ethanolamine, with the polycarboxylic acids, indicated above, or they can be obtained using the same components that make up the hydroxyl-containing polyester, with only one portion of the components being a diamine, such as ethylene diamine. Any suitable polyoxyalkylene polyether polyol can be used, such as the polymerization product of an alkylene oxide or a mixture of alkylene oxides with a polyhydric alcohol. Any suitable polyhydric alcohol, such as those mentioned above, can be used for the use in the preparation of the hydroxy-terminated polyesters. Suitable initiators include both aliphatics and aromatics, such as ethylene glycol, propylene glycol, dipropylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,4-pentanediol, 1, 5-pentanediol, 1,6-hexane-diol, 1,7-heptanediol, glycerol, 1,1-trimethylolpropane, 1,1-trimethylolethane, 1,2,6-hexanetriol, α-methyl glucoside, pentaerythritol and sorbitol. Any suitable alkylene oxide, such as those mentioned above, can be used to prepare the prepolymers. Examples of aliphenylene oxides include ethylene oxide, propylene oxide, butylene oxide, amylene oxide, mixtures thereof, tetrahydrofuran, mixtures of alkylene oxides and tetrahydrofuran, epihalohydrins and aralkylene oxides, such as styrene oxide. Polyethers that are particularly suitable include the addition products of the alkylene oxide of trimethylolpropane, glycerin, porpylene glycol, dipropylene glycol; sucrose and its mixtures, which have average molecular weights in number from 100 to 5,000. Suitable polyhydric polyethers, which can be condensed with the alkylene oxides, include the condensation product of the thiodiglycol or the reaction product of a dicarboxylic acid, such as those mentioned above, for the preparation of the hydroxyl-containing polyesters, with any other suitable thioether-glycol. Polyhydroxyl-containing phosphorus compounds, which may be used, include the compounds disclosed in U.S. Patent No. 3,639,542. Preferred polyhydroxyl-containing phosphorus compounds are prepared from alkylene oxides and phosphorus acids, having an acid equivalency of about 72 to 95 percent. Suitable polyacetals, which can be condensed with the alkylene oxides include the reaction product of the formaldehyde or other suitable aldehyde, with a dihydric alcohol or an alkylene oxide, such as those mentioned above. Suitable aliphatic thiols, which can be condensed with the alkylene oxides, include the alkane thiols, which contain at least two -SH groups, such as 1,2-ethanedithiol, 1,2-propanedithiol, 1,3-propanedithiol and 1,6-hexanediol; alkene-thiols, such as 2-butene-1, 4-dithiol; and alkynethiols, such as 3-hexyne-1, 6-dithiol. As indicated above, polyols having initiator molecules containing nitrogen are particularly suitable for use in the invention. Particularly preferred for use in the invention are polyethers resulting from the condensation of amines with alkylene oxides. Suitable amines, which can be condense with alkylene oxides, include the aromatic amines, such as aniline, o-chloroaniline, p-aminoaniline, 1,5-diaminonaphthalene, methylene aniline, the condensation products of aniline and formaldehyde, and 2,3-, 2,6-, 3,4-, 2,5-, and 2,4-diaminotoluenes (TDA) and rods of the isomers; and aliphatic amines, such as methylamine, tri isopropanolamine, ethylenediamine, 1,3-diaminopropane, 1,3-diaminobutane and 1,4-diaminobutane. Polyethers having aromatic amines as initiator molecules are most preferred. Polyols containing ester groups can also be employed in the present invention. These polyols are prepared by the reaction of an alkylene oxide with an organic anhydride of the dicarboxylic acid and a compound containing reactive hydrogen atoms. A more extensive discussion of these polyols and their method of preparation, can be found in the patents of E. U. A., Nos. 3,585,185, 3,639,541 and 3,639,542. Polyols containing dispersions of graft polymers can also be used in the invention. They are prepared by the in situ polymerization, in the polyols listed below, of an ethylenically unsaturated monomer or a mixture of ethylenically unsaturated monomers. Ethylenically representative unsaturated monomers, which may be employed in the present invention, include butadiene, isoprene, 1,4-pentadiene, 1,6-hexadiene, 1,7-octa-diene, styrene, α-methylstyrene, 2- methylstyrene, 3-methylstyrene and 4-methylstyrene, 2,4-dimethylstyrene, ethylstyrene, isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene, and the like; substituted styrenes, such as cyanostyrene, nitrostyrene, N, N-dimethylaminostyrene, acetoxystyrene, methyl 4-vinylbenzoate, phenoxystyrene, p-vinylphenyl oxide, and the like; acrylic monomers and substituted acrylic monomers, such as acrylonitrile, acrylic acid, methacrylic acid, methyl acrylate, 2-hydroxyethyl acrylate, methyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, isopropyl methacrylate, octyl methacrylate, methacrylonitrile , ethyl a-ethoxyacrylate, methyl a-acetaminoacrylate, butyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, phenyl methacrylate, N, N-dimethylacrylamide, N, N-dibenzylacrylamide, N-butylacrylamide, methacrylyl -formamide, and similar; vinyl esters, vinyl ethers, vinyl ketones, etc. , such as vinyl acetate, vinyl butyrate, isopropenyl acetate, vinyl format, vinyl acrylate, vinyl methacrylate, vinyl methoxyacetate, vinyl benzoate, vinyl toluene, vinyl naphthalene, vinyl methyl ether, vinyl ethyl ether, vinyl propyl ethers, vinyl butyl ethers, vinyl-2-ethylhexyl ether, vinyl phenyl ether, vinyl-2-methoxyethyl ether, methoxybutadiene, 2-butoxyethyl-vinyl ether, 3,4- dihydro-l, 2-pyran, 2-butoxy-2 '-vinyloxy-diethyl ether, vinyl methyl ketone, vinyl ethyl ketone, vinyl phosphonates, such as vinyl phenyl ketone, vinyl ethyl sulfone, N-methyl-N-vinyl acetamide, N-vinyl pyrrolidine, vinyl imidazole, divinyl sulfoxide, divinyl sulfone, sodium vinyl sulfonate, methyl vinyl sulfonate, N-vinyl pyrrole, and the like; dimethyl fumarate, dimethyl maleate, maleic acid, crotonic acid, fumaric acid, itaconic acid, monomethyl itaconate, t-butylaminoethyl methacrylate, dimethylaminoethyl methacrylate, glycidyl acrylate, allyl alcohol, glycol monoesters of itaconic acid, vinyl- pyridine, and the like. Any of the known polymerizable monomers can be used and the compounds listed above are illustrative and not restrictive of the monomers suitable for use in this invention. Preferably, the monomer is selected from the group consisting of acrylonitrile, styrene and mixtures thereof. The amount of the ethylenically unsaturated monomer used in the polymerization reaction is generally 25 to 70 percent, preferably 30 to 45 percent, based on the total weight of the product. The polymerization occurs at a temperature between about 25 and 180 ° C, preferably 80 to 135 ° C. The unsaturated polyols or macromers, which can be used in the preparation of a graft polymer dispersion, if used, can be prepared by the reaction of any conventional polyol, such as those described above, with an organic compound, which has both the ethylenic unsaturation as a hydroxyl, carboxyl, anhydride, isocyanate or epoxy group, or they can be prepared using an organic compound having both the ethylenic unsaturation and a hydroxyl, carboxyl, anhydride or epoxy group, as a reagent in the preparation of the conventional polyol. Representative of these organic compounds include the unsaturated mono- and polycarboxylic acids and anhydrides, such as maleic acid and anhydride, fumaric acid, crotonic acid and anhydride, propenyl-succinic anhydride, acrylic acid, acryloyl chloride, acrylate or methacrylate. hydroxyethyl and halogenated maleic acids and anhydrides, unsaturated polyhydric alcohols, such as 2-buten-l, 4-diol, glycerol, allyl ether, trimethylolpropane-allyl ether, pentaerythritol-allyl ether, pentaerythritol vinyl ether, pentaerythritol diallyl ether, pentaerythritol vinyl ether, pentaerythritol diallyl ether and 1-buten-3,4-diol, unsaturated epoxides, such as 1-vinyl-cyclohexene-3,4-epoxide, butadiene monoxide, vinyl glycidyl ether (2-vinyloxy-2,3-epoxy-propane), glycidyl methacrylate and 3-allyloxypropylene oxide (allyl glycidyl ether). Illustrative initiators of polymerization, which may be employed, are the well-known free radical types of vinyl polymerization initiators, such as peroxides, persulfates, perborates, percarbonates, azo compounds, etc. These include hydrogen peroxide, dibenzoyl peroxide, acetyl peroxide, benzoyl hydroperoxide, t-butyl hydroperoxide, di-t-butyl peroxide, lauroyl peroxide, butyryl peroxide, diisopropylbenzene hydroperoxide, eumenohydroperoxide, hydroperoxide. of paramentane, diacetyl peroxide, di-a-cumyl peroxide, dipropyl peroxide, diisopropyl peroxide, isopropyl-t-butyl peroxide, butyl-t-butyl peroxide, difuroyl peroxide, bi (triephenylmethyl) peroxide, bis (p-ethoxybenzoyl) peroxide, p-monomethoxybenzoyl peroxide, rubenium peroxide, ascaridol, t-butyl peroxybenzoate, diethyl peroxyterephthalate, propyl hydroperoxide, isopropyl hydroperoxide, n-butyl hydroperoxide, t-butyl hydroperoxide, cyclohexyl hydroperoxide, trans-hydroperoxide -decaine, a-methyl-benzyl hydroperoxide, a-methyl-a-ethyl-benzyl hydroperoxide, tetralin hydroperoxide, triphenylmethyl hydroperoxide, diphenylmethyl hydroperoxide, a, a1-azobis- (2-methyl-hepto-nitrile) , 1,1'-azo-bis- (cyclohexane-carbonitrile), 4,4'-azo-bis- (4-cyanopentanoic acid), 2, 2'-azo-bis (isobutyronitrile), lt-butylazole 1-cyanocyclohexane, persuccinic acid, diisopropyl-peroxy-dicarbonate, 2,2'-azobis (2,4-dimethylvaleronitrile), 2-t-butylazo-2-cyano-4-methoxy-4-methylpentane, 2,2 '- azobis-2-methylbutannitrile, 2-t-butylazo-2-cyanobutane, 1-t-amylazo-l-cyanocyclohexane, 2,2'-azobis (2,4-dimethyl-4-methoxivaleronitrile, 2,2'-azobis- 2-methylbutyronitrile, 2-t-butylazo-2-cyano-4-methylpentane, 2-t-butylazo-2-isobutyronitrile, to butylperoxy-isopropyl carbonate, and the like; A mixture of initiators can also be used. Preferred initiators are 2,2'-azobis (2-methylbutyronitrile), 2,2'-azobis (isobutyronitrile), 2,2'-azobis (2,4-dimethylvaleronitrile), 2-t-butylazo-2-cyano 4-methoxy-4-methylpentane, 2-t-butylazo-2-cyano-4-methylpentane, 2-t-butylazo-2-cyano-butane and lauroyl peroxide. Generally, it can be employed in the process of the invention of about 0.1 to 10 percent, preferably about 1 to 4 percent by weight of the initiator, based on the weight of the monomer. However, while many of the polyols, described above, are suitable for use in the invention, it has been found that certain polyols are particularly preferred. It has been discovered, unexpectedly, that the problems of non-homogeneity or separation behavior are greatly eliminated when the isocyanate-reactive polyol comprises at least one polyoxyalkylene polyether, which has, as an initiator molecule, a substituted aromatic molecule of amine. Preferred examples are aniline, o-chloroaniline, p-aminoaniline, 1,5-diaminonaphthalene, methylene dianiline, the condensation products of aniline and formaldehyde, and 2,3-, 2,6-, 3 , 4-, 2,5- and 2,4-diam.inotoluenes (TDA). The most preferred type of aromatic polyamine initiator is diamino-toluene, which has vicinal amino groups, ie 2,3- or 2,6-diaminotoluenes, and mixtures thereof. In addition, the most preferred polyoxyalkylene polyethers for use in the present invention will be those that have been oxypropylated. Thus, the preferred polyol for use in the present invention will be an oxypropylated TDA polyether. More preferred are polyols that generally have a relatively low molecular weight, i.e. below 1,000, and a hydroxyl number generally less than 600. An example of a preferred, commercially available polyol is PLURACOL®3 Polyol 736 from BASF Corporation, of Wyandotte, Michigan, USA. While not wishing to be bound to a particular mechanism, it is believed that the structure of the oxypropyl aromatic polyamine polyether is responsible for the observed lack of separation in the novel polyol composition of the invention. . The side or composition (II) of the polyol of the invention may also contain additional components, such as blowing agents, catalysts, chain extension agents, surfactants, adhesion promoters, stabilizers, dyes, fillers, pigments and / or its mixtures. 3 PLURACOL * is a registered trademark of BASF Corporation For example, a blowing agent, particularly preferred, is water, preferably 0.5 to 10 weight percent, and, more particularly, 1 to 5 weight percent of water, based on the weight of the polyol (A). Alternatively, instead of water alone, mixtures of water and low-boiling hydrocarbons or chemically inert halogenated hydrocarbons can also be used as foam-forming agents. Suitable hydrocarbons and halogenated hydrocarbons will be those having boiling points below 50 ° C, preferably between 50 and 30 ° C, at atmospheric pressure. Illustrative examples are halogenated hydrocarbons, such as monochlorodifluoromethane, dichloromonofluoromethane, dichlorofluoromethane and trichlorofluoromethane and mixtures thereof, as well as hydrocarbons, such as isomers of propane, butane, pentane, as well as dimethyl ether. The required amounts of the blowing agent mixture can be determined experimentally in a very simple manner, as a function of the mixing ratio of the water to the hydrocarbon blowing agents, as well as the desired densities of the foam. Suitable amounts will generally vary from about 2 to 40, preferably 5 to 25 percent, of the blowing agent, based on the weight of the polyol.

Chain extension agents and / or entanglement agents will also preferably be employed in the preparation of molded polyurethane articles. Examples of suitable chain extension and / or entanglement agents include those compounds having at least two functional groups that carry active hydrogen atoms, such as water, hydrazine, primary and secondary diamines, amino-alcohols, amino-acids, hydroxy -acids, glycols, or their mixtures. These agents will generally have a number average molecular weight of less than about 400. A preferred group of chain extension agents and / or entanglement agents include water, ethylene glycol, 1,4-butanediol, glycerin and mixtures thereof. The most preferred crosslinking agent is glycerin. The use of the catalysts is highly preferred.

Examples of suitable amine-based catalysts, which can be used, include tertiary amines, such as, for example, triethylene diamine, N-methylmorpholine, N-ethyl-morpholine, diethylethanolamine, N-co-morpholine, l-methyl-4- dimethylaminoethylpiperazine, 3-methoxypropyl dimethylamine, N, N, N '-trimethylisopropyl-propylenediamine, 3-diethylamino-propyldietyl ina, dimethylbenzylamine, and the like. Other suitable catalysts are metal-based catalysts, for example stannous chloride, dibutyltin-di-2-ethyl hexanoate, stannous oxide, as well as other organometallic compounds, as disclosed in US Pat. No. 2,846,408. . However, preferred catalysts are those commercially available amine catalysts, such as DABCO® MR-3, DABCO® BL-17, DABCO® X-8154 and DABCO® 33LV, all of which are commercially available from Air Products Corporation. A particularly suitable catalyst, based on metal, is dioctyl tin-dimercaptin, commercially available as a FOMREZ® UL-32 catalyst. The especially preferred catalyst will be a mixture of amine-based and metal catalysts. Surfactants will also preferably be incorporated in the invention. A particularly preferred surfactant is L-500, a cellular stabilizing surfactant, commercially available from Union Carbide. It is believed that the presence of this surfactant supplies improved flow characteristics. As indicated above, composition (B) of IMR will more preferably be part of component (II) of the polyol of a polyurethane system. However, it is within the scope of the invention to have an IMR composition (B) incorporated in the isocyanate component (I) of the polyurethane system. Alternatively, the components (a) and (b) of the composition (B) of IMR can, respectively, be incorporated, separately, into the component (II) of the polyol and the component (I) of isocyanate. In any case, the concentrations of (a) and (b) will be as previously provided. The isocyanate reactive polyol component (II) of the invention is generally combined with an isocyanate component (I) to deliver polyurethane compositions of the invention. The polyurethane compositions of the invention are suitable for the preparation of molded SRIM polyurethane articles, which have internal mold release properties. Isocyanate components (I) suitable for use according to the invention are the organic isocyanates. The organic polyisocyanates used in the present invention correspond to the formula R '(NCO) z, where R 1 is a polyvalent organic radical, which is aliphatic, arylalkyl, alkylaryl, aromatic or mixtures thereof, and z is an integer which corresponds to the valence of R 'and is at least 2. Representative of the types of organic polyisocyanates considered here include, for example, 1,2-diisocyanatoethane, 1,3-diisocyanatopropane, 1,2-diisocyanatopropane, 1,4 -diisocyanatobutane, 1,5-diisocyanatopentane, 1,6-diisocyanatohexane, bis (3-isocyanato-propyl) ether, bis (3-isocyanatopropyl) sulfide, 1,7-diisocyanatoheptane, 1,5-diisocyanate-2 , 2-dimethylpentane, 1,6-isocyanato-3-methoxyhexane, 1,8-diisocyanatoctane, 1,5-diisocyanato-2,2,4-trimethylpentane, 1,9-diisocyanatononane, 1, 10-diisocyanatopropyl ether of 1 , 4-butylene glycol, 1,11-diisocyanato-decane, 1,1-diisocyanatododecane, bis (isocyanatohexyl) sulfide, 1,4-diisocyanatobenzene, 1,3-diisocyanate oo-xylene, 1,3-diisocyanate-p-xylene, 1,3-diisocyanate-m-xylene, 2,4-diisocyanato-l-chlorobenzene, 2,4-diisocyanato-l-nitro-benzene, 2, 5-diisocyanate-l-nitro-benzene, m-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- or 2,6-toluene diisocyanates, diisocyanate of 16 hexamethylene, 1,4-tetramethylene diisocyanate, 1,4-cyclohexane diisocyanate, hexahydrotoluene diisocyanate, 1,5-naphthalene diisocyanate, l-methoxy-2,4-phenylene diisocyanate, 4,4'-diisocyanate. cyclohexane, hexahydrotoluene diisocyanate, 1,5-naphthalene diisocyanate, 1-methoxy-2,4-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4-biphenylene diisocyanate, 3,3 'diisocyanate -di-methyl-4,4 '-diphenylmethane, 3,3' -dimethyl-4,4'-diphenylmethane, 3,3'-dimethyldiphenylmethane-4,4'-diisocyanate and 3,3'-dimethyldiphenylmethane-4-diisocyanate , 4 * -diisocyanate; triisocyanates, such as the 4,4 ', 4"-triphenyl-methane triisocyanate, polymethylene and polyphenylene polyisocyanate and 2,4,6-toluene triisocyanate, and tetraisocyanates, such as tetraisocyanate 4, 4'-dimethyl-2, 2'-5, 5'-diphenylmethane, especially useful, due to its availability and its properties are the toluene diisocyanate, 2,4-diiphenylmethane diisocyanate, 4'-diphenylmethane diisocyanate, polyisocyanate of polymethylene and polyphenylene, and mixtures thereof Polyisocyanates are prepared by conventional methods known in the art, such as the phosgenation of the corresponding organic amine, and included within the isocyanates that can be used are modifications of the above isocyanates, which they contain carbodiimide, allophonate or isocyanurate structures.The quasi-prepolymers can also be used in the process of the present invention.These quasi-prepolymers are prepared by reacting a excess of an organic polyisocyanate, or mixtures thereof, with a minor amount of an active hydrogen-containing compound, as determined by the well-known Zerewitinoff test, described by Kohler in Journal of the American Chemical Society, 49, 3181 (1927) ). These compounds and their methods of preparation are well known in the art. The use of any specific compound of active hydrogen is not critical here, rather any of such compounds can be employed. In general, quasi-prepolymers have a free isocyanate content of 20 to 40 weight percent. The component (I) of isocyanate and the component (II) of polyol will generally be combined in a ratio of 60 to 120, and preferably in a ratio of 80 to 110.

The most preferred ratio for the polyurethane composition will be from 85 to 95. The polyurethane composition of the invention can be used with various reinforcement materials to produce SRIM articles in both conventional SRIM processes and casting delay processes. As indicated above, conventional SRIM processes generally require the emptying of a liquid polyurethane composition within a mold, open or closed, which, if open, subsequently closes during the foaming reaction. Before pouring into the liquid foam composition, the reinforcing materials and / or reinforcement parts are placed in the open mold. Reinforcing materials suitable for use in producing SRIM articles include a wide variety of materials. Fiber reinforcements are preferred. The fiber materials can be woven, non-woven (random), or combinations thereof. Suitable fibers include synthetic fibers of nylon, polyester, aramid, polyether ketones, polyether sulfones, polyamides, silicon-carbon, and the like; natural fibers, such as cellulose, cotton, hemp, flax and jute; and mineral or ceramic fibers, which include Wolastonite, aluminum, glass fibers and carbon fibers. A unique material, not glass, is Colbac ®4 nonwoven, 4 Colbac ® is a registered trademark of AKZO Corporation spunbonded, comprising a biocomponent fiber having a polyester core and polyamide skin, available from AKZO Corporation, of Enka, NC. , E. U. A. Glass fibers, woven or non-woven, are the preferred reinforcing materials, due to their low cost and physical properties. One or more fiber reinforcing layers may be used, depending on the desired weight of the fibers. Up to 70 percent by weight of the SRIM piece can comprise the reinforcing material. In general, this reinforcing material will be laid directly into the mold and the liquid composition of polyurethane foam is emptied there. However, alternatively or additionally, staple fibers and other fillers may be added to the isocyanate component of the system, the polyol component or both, in amounts up to 70 percent by weight of the SRIM piece. However, the SRIM processes in which the glass fiber mats are placed in the mold, prior to injection of the polyurethane composition, are preferred. In addition to the reinforcing material of fibers, parts or structural elements, comprised of wood, metal and / or plastic materials, known to those skilled in the art, they can be supplied into the mold, before, or after, the placement of the fiber reinforcement in the open mold. The metal or plastic elements are preferred. Examples of suitable plastic materials include ABS, nylon, acetyl, polypropylene, polyethylene, PVC, and the like. In any case, the liquid composition of polyurethane foam will generally be applied to the last, before closing the mold or the beginning of the molding. In traditional SRIM processes, after the molding of the SRIM article, this article will be trimmed. However, in some cases, the molded SRIM article will be used as a component for a composite article. For example, a cover material may be supplied within an open mold, followed by the molded SRIM article. A flexible or semi-flexible polyurethane foam is then injected into the mold containing the cover material and the molded SRIM article. The foam, flexible or semi-flexible, is allowed to react to bond to the cover material and the molded SRIM article, in a single composite article. Alternatively, composite articles can be obtained using post-fill or delayed pouring process techniques. For example, in a typical lagging delay process, a cover material is supplied in a foam. Such cover materials may or may not have an expanded foam backing. Optionally, a second foam, such as a foam that absorbs energy, can be placed in the upper part of the mold. Alternatively, reinforcing materials can be placed inside the mold. The liquid polyurethane composition is subsequently emptied onto the cover material and molding is started. In an open mold, the molding will be initiated when closing the mold. The foam is allowed to react for a sufficient period of time to fully react and adhere to the cover material and any other component element, previously placed in the mold. Examples of suitable cover materials are vinyl, polyvinyl chloride, polypropylene, polyethylene, fabrics, polyurethane foams, including those rigid, flexible, semi-flexible and energy absorbing, and mixtures thereof. Those skilled in the art will appreciate that, with respect to the post-fill SRIM processes, the cover materials are often referred to as 'vinyl', when they are not comprised of polymeric ethylene. As used herein, the term "vinyl" is intended to encompass both the traditional chemical meaning (ie, polymeric ethylene) and the meaning typically given by those familiar with the SRIM molding process. The cover materials can be formed prior to insertion into the mold of the composite article by vacuum forming. Alternatively, the cover material can be formed of PVC, which has been rotationally molded. A discussion of such processes can be found in the manual Polyurethane Handbook, G. Oretal, Section 5.4, pages 223-225, which is incorporated herein by reference. It will be appreciated that the presence of several internal component elements requires that the internal mold release agent does not interfere with the adhesion of the SRIM article. The molded SRIM articles, which have internal mold release properties, according to the invention, will generally have densities of 160 to 480 kg / m 3 without glass and 240 to 640 kg / m 3 with the glass. More preferably, the densities of the SRIM articles of the invention will have densities of 320 to 560 kg / m 3. They are also characterized by a warpage of approximately 0.25 to 0.75 percent and a dimensional stability not greater than 0.10 to 382C and 100% relative humidity. The dimensional stability in 24 hours and at 702C will not be less than 0.01 percent. The tensile strength of molded SRIM articles varies from 140 to 280 kg / cm2. The flexural strength is 210 to 490 kg / cm2 and the flexural modulus is 7 K kg / cm2 up to 14 K kg / cm2. The molded articles showed no cracks and had an impact resistance of 0.9 Joules, at 23 seconds. The following working examples indicate the manner and process to obtain and use the invention and indicate the best mode considered by the inventors to carry out the invention, but should not be construed as limiting. The following ingredients were used to illustrate the various compositions of the invention: Polyol A is a propylene oxide adduct of the toluene diamine having a hydroxyl number, OH, of 390. Polyol B is an oxide adduct. of propylene glycerin, having an OH number of 398. Polyol C is a propylene oxide adduct of sucrose / diethylene glycol, which has an OH number of 397. Polyol D is an oxide adduct of propylene glycerin, which has an OH number of 935. Polyol E is a polyester polyol, having an OH number of 65. DABCO® is a delayed gel catalyst, commercially available from Air Products Corporation. POLYCAT® SA-1 is a delayed blow catalyst, commercially available from Air Products. Fluid 5000 from Dow Corning® is a silicon-containing polymer, commercially available from Dow Corning or Air Products Corporation.

FOMREZ®5 UL-32 is a dioctyl tin dimercaptide catalyst, commercially available from Witco Corporation. LEXOREZ®6 1721-65 is an adhesion promoter, commercially available from Inolex Corporation. TEGOS ® B 8863Z is a cellular stabilizer, commercially available from Goldschmidt Chemical. XFK-1546® is a silicone surfactant, commercially available from Air Products Corporation and believed to be equivalent to DC-500. PALATINOL®7 11P-E is a di-undecyl phthalate and is commercially available from BASF Corporation. EP-8 is an epoxidized talate, commercially available from Union Carbide. DRAPEX®8 6-8, is an epoxidized soybean oil, commercially available from Witco. Isocyanate A is a polymeric MDI, which is about 45 to 47 weight percent, MDI of 2 rings; 19 weight percent MDI of 3 rings; and 30-33 weight percent of n-ring MDI oligomers, where n > 3. The isocyanate has an NCO content of 31.6 weight percent.

FOMREZ® is a registered trademark of Witco Corporation. 6 LEXOREZ »is a registered trademark of Inolex Corporation. 7 PALATINOL® is a registered trademark of BASF AG. 8 DRAPEX® is a registered trademark of Witco Corporation.

EXAMPLE 1 The following example illustrates the unexpected results achieved with the internal mold release composition of the invention. Three polyol components were prepared, which have the formulations indicated below: POLYOL COMPOSITIONS Each of the above polyol compositions A, B and C were combined with isocyanate A in a ratio of 110, ie 100 parts of polyol to 100 parts of isocyanate, to form three different polyurethane compositions A, B and C. For each SRIM piece , a fiberglass mat weighing between 200 and 300 grams was used, with the average weight of the mat being approximately 222 grams.

The fibers of glass used were 28.35 grams of fibers NICO 754. The parts were molded in a high pressure distributor machine, EMB PU SV. The mold used was a door mold and had a metal surface and internal heating coils. The surface temperature of the mold was approximately 65.50C. The internal temperature of the closed mold was 65.5SC. For the operation of each piece, the mold, which has an approximate dimension of the piece of 61 cm. x 91 cm., was charged with the above polyurethane compositions, each component, ie the isocyanate (I) and the polyol (II) side had a temperature of 272C. The intention was to mold as many pieces as possible, until the quality of the release is considered not acceptable, that is, it fails in its easy and fast exit. The surface of the mold was prepared initially by removal with a solvent followed by a soap (Ivory bar soap) and washing with water. This was followed by an initial application of a light coating of LH-1, a hydrocarbon-based wax, commercially available from Chemtrend of Howell, Mich., E. U. A., It took five passes of the fill arm to fill the mold. It took approximately 14 seconds to hold the mold. The healing occurred 60 seconds after the restraint.

The results indicate that the polyurethane composition of the invention, ie the composition B, performs advantageously in comparison with the prior art compositions. EXAMPLE 2 The effect of the compounds (a) and (b) alone, as compared to that of (a) and (b) together, was measured. The following polyol compositions were prepared.

The above polyol compositions 1, 2 and 3 were combined with iso A at a ratio of 100 to form polyurethane compositions 1, 2 and 3. The plates were obtained manually using a 30.48 cm aluminum mold. x 30.48 cm. x 6.35 mm, prepared initially by removal with a solvent, followed by a soap (Ivory bar soap) and washing with water. This was followed by two coatings of LH-1, a hydrocarbon-based wax, commercially available from Chem-Trend of Howell, Michigan, E. u. A. A fiberglass mat, weighing 200 to 300 grams, was used, with the average weight of the mat being around 222 grams. The glass fibers used were the NICO 754, in an amount of 28.35 grams.

The attempt was to mold successive mold plates until an unacceptable stickiness occurred. Fifteen successive plates were molded using polyurethane composition No. 1. All 15 releases, including the last one, were excellent. The successive molding was stopped using the polyurethane composition No. 1, due to the lack of the glass fiber mat. The polyurethane composition No. 2 exhibited poor flow and was stuck after the second molding. The resulting foam, partially cured, had to be removed from the surface of the mold. Three plates were molded using polyurethane composition No. 3. The last release was extremely poor and stuck to the surface of the mold. Therefore, neither the presence of the silicone (a) alone, (composition No. 2) nor the compound (b) alone (Composition No. 3), provided acceptable results. Rather, there is an unexpected synergism between (a) and (b), which produces an internal mold release agent, ie that used in composition No. 1, which provides advantageous results. EXAMPLE 3 The effect of compound (b) alone was compared in comparison to (a) and (b) together and again measured using a different polyol. The following polyol compositions were prepared.

The above compositions of polyol 4 and 5 were combined with Iso A at a ratio of 100, to form polyurethane compositions 4 and 5. The reactivity of the manual mixture was as follows: The plates were obtained manually using a 30.48 cm aluminum mold. x 30.48 cm. x 6.35 mm The surface of the mold was prepared initially by stirring with solvent, followed by a soap (Ivory bar soap) and washed with water. This was followed by an initial application of a lye-free coating of LH-1, a hydrocarbon-based wax, commercially available from Chemtrend of Howell, Mich., E. U. a. Successive plates were molded until tack occurred and the application of an external mold release agent became necessary. Ten plate releases were obtained using polyurethane composition No. 4. Only 2 plate releases were possible using the polyurethane composition No. 5. The plates obtained with the polyurethane composition No. 5 stuck strongly to the surface of the mold.

Thus, as a result of the use of the compositions of the invention, the need to spray additional IMR agents is substantially reduced. The average performance properties of the resulting finished parts, produced according to Example 1 and using the polyurethane composition, Formulation R. are as follows: PHYSICAL PROPERTIES VALUE Density (with glass) 540 kg / m3 Foam density 416.5 kg / m3 Pandeo 0.12 Dimensional stability 0.05 to 38SC and 100% RH Dimensional stability 0.05 24 hours and 70dC Resistance to tension 191 kg / cm2 Resistance to bending 362.6 kg / cm2 Bending module 11389 kg / cm2 Resistance to impact, no cracks formed at 0.9 Joules and 232 C Glass fibers, weight 305 g / m2

Claims (6)

1. CLAIMS 1. A molded polyurethane article, having internal mold release properties, produced by the process of: providing a mold; placing within the mold, a composition comprising: I.) an isocyanate component; and II.) an isocyanate reactive polyol component, this component includes: A.) an isocyanate reactive polyol, having a molecular weight of from 100 to about 10,000; and B.) an effective amount of an internal mold release composition, which is composed of: a.) a silicon-containing polymer; and b.) at least one diester functional compound, which is the reaction product of: (i) an aromatic dicarboxylic acid; e (ii) alcohols, having from 2 to 30 carbon atoms; and allowing the composition to react within the mold, for a sufficient time to produce a molded polyurethane article, having internal mold release properties; and remove this molded polyurethane article from the mold.
2. 2. The molded polyurethane article according to claim 1, produced by the process in which the cast composition within the mold comprises an internal mold release agent (B), having at least one functional diester compound (b), comprising the reaction product of: (i) an aromatic dicarboxylic acid, having 8 to 12 carbon atoms; e (ii) one or more monofunctional aliphatic alcohols, having from 4 to 15 carbon atoms.
3. 3. The molded polyurethane article according to claim 2, produced by the process in which the composition placed inside the mold comprises an internal mold release agent (B), having at least one functional diester compound (b), which it comprises the reaction product of: (i) an aromatic dicarboxylic acid, having from 8 to 12 carbon atoms; e (ii) one or more aliphatic monofunctional alcohols, having from 8 to 11 carbon atoms.
4. 4. The molded polyurethane article according to claim 3, produced by the process in which the composition placed inside the mold includes an internal mold release agent (B), having a compound (b) comprising the reaction product of: (i) an aromatic dicarboxylic acid, selected from the group consisting of phthalic acid, terephthalic acid and isophthalic acid; e (ii) an aliphatic monofunctional alcohol, having from 8 to 11 carbon atoms.
5. 5. The molded polyurethane article according to claim 4, produced by the process in which the composition placed inside the mold comprises an internal mold release agent (B), where compound (b) is di-undecyl phthalate .
6. 6. The molded polyurethane article according to claim 1, produced by the process in which the composition placed inside the mold has an isocyanate reactive polyol component, which comprises: an isocyanate reactive polyol (A), which includes at least one polyoxyalkylene polyether polyol, having a nitrogen-containing molecule, as an initiator; and an effective amount of an internal mold release composition (B), which consists of: from 1 to 50 parts by weight of a polydimethylsiloxane (a) functional secondary hydroxyl; from 50 to 99 parts by weight of the compound (b), these parts by weight are based on the weight of the internal mold release composition (B).