MXPA98009131A - Foams with integrated coating that use propane pentafluoro as blown agents - Google Patents

Abstract

It has been found that non-chlorinated pentafluoropropane blowing agents can be used alone, or in combination with water, in flexible foams with integrated coating. For example, foams prepared using 1,1,1,3,3-pentafluoropropane (HFA-245fa) alone or in combination with water, exhibit physical characteristics such as abrasion resistance and flex cracking comparable to blown foams with conventional chlorinated fluorocarbons. The foams of the present invention are suitable for use in multiple applications including, for example, shoe soles

Description

FOAMS WITH INTEGRATED COATING THAT USE PENTAFLUORO- PROPANE AS BLOWING AGENTS FIELD OF THE INVENTION The present invention relates to foams with coating, integrals, and to a process for preparing these foams. More specifically, the invention relates to coated foams employing pentafluoropropane as the sole blower or with water, as a co-blowing agent.

BACKGROUND OF THE INVENTION Coated foams are well known to those skilled in the art of polyurethane foams. These foams have an alveolar interior and a microcellular coating of higher density or non-cellular. In general, to prepare these foams an organic isocyanate is reacted with a substance having at least one reactive isocyanate group in the presence of a catalyst, blowing agent and a variety of optional additives. The reaction is carried out in a mold where a higher density coating is formed at the interface of the reaction mixture and the relatively cold internal surface of the foam. Previously, the most common types of blowing agent that were used in the polyurethane foams with coating, integrated chlorofluorocarbons (CFCs) or combinations of CFCs and other blowing agents. However, in view of the recent stockpiles due to a reduction and finally the elimination of the use of CFCs, alternatives are considered necessary. The above methods for preparing coated polyurethanes, integrated with CFC as a blowing agent, include GB Patent No. 1,209,297, which teachings of the use of a blowing agent combination consist of a CFC and a hydrate of an organic compound that removes water at temperatures above 40 ° C. This blowing agent or combination of agents was used in a formulation with a suitable polyisocyanate, a polyol containing hydroxyl groups and a catalyst. This patent discloses that the free water in the system causes a coating that is permeated with fine cells, which is undesirable. Attempts have been made to evaluate the operation of alternative blowing agents to CFCs. In a document of J.L.R. Clatty and S.J. Harasin titled, Performance of Altérnate Blowing Agents to Chlorofluorocarbons in RIM Structural and Elastomeric Polyurethane Foa, presented at the Annual Conference on Technical Aspects / Marketing of Polyurethanes, October 1989, the authors considered the use of water as a blowing agent for systems injection molded with polyurethane reaction (RIM) with skin or integrated coating. In this application, the concentration of water in the system is controlled by the concentration and type of molecular sieves that are used. As in the Great Britain Patent described above, water is not found in a free form but is bound in some way. In this case, the authors state that this process is limited to use in rigid foam systems; and formulations for flexible integrated coatings can be best served using HCFC or HCFC-22 as CFC substitutes. An integrated, newly-employed, foamed foam formulation is described in U.S. Patent No. 5,100,922 to Wada et al, which relates to a method for producing a molded polyurethane foam product with an integrated coating. The method consists in reacting and curing (1) a high molecular weight polyol containing, as the main component, an oocyloxyalkylene polyol having, as the main constituent, oxyalkylene groups of at least 3 carbon atoms and oxyethylene groups in its molecular terminals, the total content of the oxyethylene group being not more than 15% by weight and with a hydroxyl number not greater than 80, (2) a crosslinking agent consisting of a compound having an aromatic nucleus and at least two groups containing active hydrogens that are selected from the group consisting of hydroxyl groups, primary amino groups and secondary amino groups, and (3) a polyisocyanate, in a mold, in the presence of a catalyst and a halsgenated hydrocarbon foaming agent containing hydrogen atoms. Although an extensive list of blowing agents is provided, only the pentafluoro compounds described are chlorinated compounds such as 3, 3-dichloro-1,1,2,2-pentafluoropropane and 1,3-dichloro-1,2, 2, 3-pentafluoropropane, which are considered undesirable. Recently, U.S. Patent 5,506,275 published by Valoppi, the inventor of the present invention relates to the use of 1,1,1,2-tetrafluoroethane as an alternative to conventional chlorinated fluorocarbon blowing agents in the formulations of foamed integrated foams. While these patents offer an alternative to halogenated hydrocarbon blowing agents, 1,1,2-tetrafluoroethane (HFC-134a) boils at -26.5 ° C and thus requires special gas supply systems to introduce and maintain the agent blower in solution, especially in hot climatic conditions, that is, above 90 ° F (32 ° C). Like these, other improvements in the technique are still considered necessary. It has been found that foams using pentafluoropropane blowing agents and, in particular, 1,1,1,3,3-pentafluoropropane as the blowing agent only or in combination with limited amounts of water can be prepared, which meet the requirements strict adherence to the applications of the foams with integrated coating, as it can be an acceptable appearance and must present improved resistance to abrasion and cracking with bending. In addition, the pentafluoropropane blowing agents used in the present invention are generally soluble in resinous solution thereby eliminating and greatly reducing the need for specialized gas supply systems to maintain the pressure in the system.

SUMMARY OF THE INVENTION The object of the present invention is to provide a flexible, low density, integrated polyurethane foam, capable of being used in various applications, consisting of the reaction product of: a) a polyisocyanate component; and b) an active hydroxy-functional polyol composition; in the presence of: c) a blowing agent including a non-chlorinated pentafluropropane and, optionally, water; d) a catalyst; and e) optionally, one or more compounds that are selected from the group consisting essentially of chain extenders, a surfactant, an alcohol having from 10 to 20 carbon atoms, fillers, pigments, antioxidants, stabilizers and mixtures thereof. . The general process consists in reacting a polyisocyanate component with a reactive isocyanate compound in the presence of a catalyst of a type known to those skilled in the art, and a non-chlorinated pentafluropropane blowing agent, optionally in association with water as a co-blowing agent. blown. A catalyst that helps in the control of foam formation can be used as well as a surfactant to control the size and structure of the cells.

DETAILED DESCRIPTION OF A PREFERRED EMBODIMENT OF THE INVENTION The organic polyisocyanates used in the present process contain isocyanate groups linked by aromatic linkages. Representative types of the organic polyisocyanates contemplated herein include, for example, 1,4-benzene diisocyanate, 1,3-o-xylene diisocyanate, 1,3-p-xylene diisocyanate, 1,3- m-xylene diisocyanate, 2,4-diol-1-nitrobenzene diisocyanate, 2-nitrobenzene-diisocyanate, m-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures 2,4- and 2,6-toluene diisocyanate, 4,4'-biphenylylene diisocyanate, 4,4'-diphenyl-diisocyanate, 3,3'4,4'-diphenylmethane diisocyanate and 4,4'-diisocyanate 3, 3'-dimethyldiphenylmethane diisocyanate; io triisocyanates such as 4,4 ', 4"-triphenylmethane triisocyanate, polymethylene polyphenylene polyisocyanate and 2, β-toluene triisocyanate; and tetraisocyanates such as 4,4-dimethyl-2,2'-5'-diphenylmethane tetraisocyanate. Especially useful due to their availability and properties are 2,4 '-diphenylmethane diisocyanate, 4,4'-diphenylmethane diisocyanate, polymethylene polyphenylene polyisocyanate and mixtures thereof. These polyisocyanates are prepared by conventional methods known in the art such as phosgenation of the corresponding organic amine. Included within the usable isocyanates are the modifications of the above isocyanates - which contain carbodiimide, allophanate, alkylene or isocyanurate structures. In the process of the present invention it is also possible to use the quasiprepolymers. These quasi-polymers are prepared by reacting an excess of organic polyisocyanate or mixtures thereof with a minor amount of an active hydrogen-containing compound determined by the well-known Zerewitinoff test, as described by Kohler in the 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 compound with specific active hydrogen is not crucial for this; on the other hand, any compound can be used in the present. In general, the quasi-prepolymers have a free isocyanate content from 20 to 40% by weight. Mixtures of polymeric diphenylmethane diisocyanate (polymeric MDI) and carbodiimide or urethane-modified MDI are preferred. The reactive isocyanate composition, otherwise referred to herein as a polyol composition with active hydroxy functional groups can include any suitable polyoxyalkylene polyether polyol as those resulting from the polymerization of a polyhydric alcohol and an alkylene oxide. Representative of these alcohols may include ethylene glycol, propylene glycol, trimethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,4-pentanediols, 1,5-pentanediol, 1,6-hexanediol, 1,7 heptanediol, glycerol, 1,1-trimethylol propane, 1,1,1-trimethylol ethanol or 1,2,6-hexanetriol. Any suitable alkylene oxide can be used as ethylene oxide, propylene oxide, butylene oxide, amylene oxide and mixtures of these oxides. The polyoxyalkylene polyether polyols can be prepared from other starting materials such as tetrahydrofuran and mixtures of alkylene oxide-tetrahydrofuran, epihalohydrins such as epichlorohydrin, as well as aralkylene oxides such as styrene oxide. The polyoxyalkylene polyether polyols may have primary or secondary hydroxyl groups. Included among the polyether polyols are polyoxyethylene glycol, polyoxypropylene glycol, polyoxybutylene glycol, polytetramethylene glycol, block copolymers, for example, combinations of polyhoxypropylene and polyoxyethylene glycols, poly-1, 2-oxybutylene and polyoxyethylene glycols and glycols. polymeric prepared mixtures or sequential addition of two or more alkylene oxides. The polyoxyalkylene polyether polyols can be prepared by any of the known processes, such as the process described by Wurtz in 1859 and Encyclopedia of Chemical Technology, Vol. 7, p. 257-262 published by Interscience Publishers, Inc. (1951) or in U.S. Patent No. 1,922,459. Other polyoxyalkylene polyether polyols that can be used are those containing grafts in the same vinyl monomers. The polyols having vinyl polymers incorporated therein can be prepared (1) by in situ free radical polymerization of a monomer or mixture of ethylenically unsaturated monomers in a polyol, or (2) by dispersion of a polyol of a polymer preformed graft that is prepared by free radical polymerization in a solvent as described in U.S. Patent Nos. 3,931,092; 4,014,846; 4,093,573; and 4,122,056; the descriptions of which are incorporated herein by reference, or (3) by polymerization at low temperature in the presence of chain transfer agents. These polymerizations can be carried out at a temperature between 65 ° C and 170 ° C, preferably between 75 and 135 ° C. The amount of the ethylenically unsaturated monomer used in the polymerization reaction is generally from 1% to 60%, preferably from 10% to 40%, based on the total weight of the product. The polymerization is carried out at a temperature between about 80 ° C and 170 ° C, preferably from 75 ° C to 135 ° C. Polyols that can be used in the preparation of graft polymer dispersions are well known in the art. Both conventional polyols essentially free of ethylenic unsaturation and those described in US Patent No. RE 28,715 and unsaturated polyols such as those described in US Pat. No. 3,652,659 and RE 29,014 can be used in the preparation of dispersions of graft polymers used in the present invention, the descriptions of which are incorporated by reference.

Representative polyols substantially free of ethylenic unsaturation that can be employed are well known in the art. These are usually prepared by catalytic condensation of an alkylene oxide or mixture of alkylene oxides either simultaneously or in sequence with an organic compound having at least two active hydrogen atoms as mentioned in U.S. Patent Nos. 1,922,459; 3,190,927; and 3,346,557, the descriptions of which are incorporated by reference. The unsaturated polyols which can be used for the preparation of the graft copolymer dispersions can be prepared by the reaction of any conventional polyol, such as those described above, with an organic compound having ethylenic unsaturation and a hydroxyl, carboxyl, anhydride group, isocyanate or epoxy; or they can be prepared using an organic compound having ethylenic unsaturation and a hydroxyl, carboxyl, anhydride or epoxy group as a reactant 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 and halogenated maleic acids and anhydrides, unsaturated polyhydric alcohols such as 2-butene 1,4-diol, glycerol allyl ether, trimethylol propane allyl ether, pentaerythritol, allyl ether, pentaerythritol vinyl ether, pentaerythritol diallyl ether and l-buten-3,4-diol, unsaturated epoxides such as 1-vinicyclohexene monoxide, butadiene monoxide, vinyl glycidyl ether, glycidyl methacrylate and 3-allyloxypropylene oxide. As already mentioned, the dispersions of the graft polymer used in the invention are prepared by the in situ polymerization of an ethylenically unsaturated monomer or a mixture of ethylenically unsaturated monomers or a mixture of ethylenically unsaturated monomers [sic], with a solvent or in the polyols described above. Representative ethylenically unsaturated monomers that can be employed in the present invention include butadiene, isoprene, 1,4-pentadiene, 1,5-hexadiene, 1,7-octadiene, styrene, α-methylstyrene, methylstyrene, 2, -dimethylstyrene, ethylstyrene. , isopropylstyrene, butylstyrene, phenylstyrene, cyclohexylstyrene, benzylstyrene and the like; substituted radicals such as chlorostyrene, 2,5-dichlorostyrene, bromostyrene, fluorostyrene, trifluoromethylstyrene, iodostyrene, cyanostyrene, nitrostyrene, N, N-dimethylaminostyrene, acetoxystyrene, methyl-4-vinyl benzoate, phenoxystyrene, p-vinyl diphenyl sulfide, p-vinylphenyl phenyloxide , and the like; substituted acrylic and acrylic monomers such as acrylonitrile, acrylic acid, methacrylic acid, ethylacrylate, 2-hydroxyethyl acrylate, 2-hydroxyethyl methacrylate, methyl methacrylate, cyclohexyl methacrylate, benzyl methacrylate, isopropyl methacrylate, octyl methacrylate, methacrylonitrile . ' methyl a-chloroacrylate, ethyl a-ethoxyacrylate, methyl a-acetam [sic], inocrylate [sic], butyl acrylate, 2-ethylhexyl acrylate, phenyl acrylate, phenyl methacrylate, α-chloroacrylonitrile, methacrylonitrile, N , N-dimethylacrylamide, N, N-dibenzylacrylamide, N-butylacrylamide, methacrylformamide and the like; vinyl esters, vinyl ethers, vinyl ketones, etc., such as vinyl acetate, vinyl chloroacetate, vinyl alcohol, vinyl butyrate, isopropenyl acetate, vinyl format, vinyl butyrate, isopropenyl acetate, vinyl format, vinyl methacrylate, vinyl ethoxyacetate, vinyl benzoate, vinyl iodide, vinyltoluene, vinylnaphthalene, vinyl bromide, vinyl fluoride, vinylidene bromide, 1-chloro-1-fluoroethylene, vinylidene fluoride, vinyl methyl ether, other vinyls , vinyl propyl ether, vinyl butyl ether, vinyl 2-ethylhexyl ether, vinyl phenyl ether, vinyl 2-butoxyethyl ether, 2,4-dihydro-l, 2-pyran, 2-butoxy-2 '-vinyloxy diethyl ether, vinyl 2 -ethylthioethyl ether, vinyl methyl ketone, vinyl ethyl ketone, vinyl phenyl ketone, vinyl phosphonates such as bis (p-chloroethyl) vinyl phosphonate, vinyl ethyl sulfide, vinyl ethyl sulfone, N-methyl-N-vinyl acetamide, N- vinyl pyrrolidine, vinyl imidazole, divinyl sulfide, divinyl sulfoxide, divinyl sulfone, v sodium inylsulfonate, methyl vinyl sulfonate, N-vinylpyrrole and the like; dimethyl fumarate, dimethyl maleate, acid, lexicon, crotonic acid, fumaric acid, itaconic acid, monomethyl itaconate, butylaminoethyl methacrylate, dimethylamino ethyl methacrylate, glycidyl acrylate, allyl alcohol, glycol mono-esters of itacic acid [sic] , dichlorobutadiene, vinylpyridine and the like. It is possible to use any of the known polymerizable monomers, and the aforementioned compounds are illustrative and not limiting of the monomers suitable for use in this invention. Preferably, the monomer is selected from the group consisting of acrylonitrile, styrene, methyl methacrylate, and mixtures thereof. The total amount of the active hydroxy-functional polyol composition that is employed according to the teachings of the present invention - includes from about 60 pep to about 100 pep, based on a total of 110 parts by weight (pep) of the resin and a foam index of between about 96-104. More preferably, the total amount of the active hydroxy-functional polyol composition will be from about 65 pbw to about 95 pbw based on a total of the weight parts of the resin of 110. -4-methoxy-4-methylpentane, 2-t-. ,,,. , butylazo-2-cyano-4- illustrative which can be used for methiipentane,,. . . - -. . Vinyl monomers are the known types of vinyl initiators, for example, peroxides, or, percarbonates, azo compounds, and hydrogen, dibenzoyl peroxide, acetyl peroxide, benzoyl hydroperoxide, hydroperoxide t-butyl, lauroyl peroxide, butyryl peroxide, Diisopropylbenzene hydroperoxide, eumeno hydroperoxide, paramentane hydroperoxide, di-a-cumyl peroxide, dipropyl peroxide, diisopropyl peroxide, difuroyl peroxide, ditriphenylmethyl peroxide, bis (p-methoxybenzoyl) peroxide, p-monoethoxybenzoyl peroxide , rubenium peroxide, ascaridol, t-butyl peroxybenzoate, peroxyethyl-diethyl phthalate, propyl hydroperoxide, isopropyl hydroperoxide, n-butyl hydroperoxide, cyclohexyl hydroperoxide, trans-decalin hydroperoxide, a-methylbenzyl hydroperoxide, hydroperoxide of a-methyl-a-ethylbenzyl, tetralin hydroperoxide, triphenylmethyl hydroperoxide, diphenylmethyl hydroperoxide, a, a'-azobis (2-methyl) heptonitrile, 1,1-azo-bis (1-cycloheanocarbonitrile), dimethyl a, a'-azobis (isobutyronitrile), 4,4'-azobis (cyanopetanoic acid), azobis (isobutyronitrile), 1-t-amylazo-l-cyanocyclohexane, 2-t-butylazo-2-cyano-4-methoxy-4-methylpentane 2- (t-butylazo) -2-cyan o-4-methylpentane, 2- (t-butylazo) isobutyronitrile, 2-t-butylazo-2-cyanobutane, 1-cyano-l- (t-butylazo) cyclohexane, t-butyl peroxy-2-ethyl hexanoate, perpivalate of t-butyl, 2,5-dimethyl-anoxy-2, 5-diper-2-ethyl hexoate, t-butyl-perneo decanoate, t-butyl perbenzoate, t-butyl perchotoate, persuccinic acid, diisopropyl peroxydicarbonate and the like; it is also possible to use a mixture of initiators, it is also possible to employ photochemically sensitive radical generators, generally from about 0.5% to about 10%, preferably from about 1% to about 4% by weight of the initiator, based on the weight of the monomer, will be used in the final polymerization. During the process of preparing the dispersions of the graft polyols it is possible to use stabilizers. One such example is the stabilizer described in US Patent No. 4,148,840, which consists of a copolymer having a first portion composed of an ethylenically unsaturated monomer or a mixture of these monomers and a second portion which is a polymer of propylene's OXID. Other stabilizers that may be employed are the alkylene oxide addition products of the styrene / allyl alcohol copolymers. Preferred polyols are polyethers having an average functionality of about 1.75 to about 3.0 and a molecular weight range of about 3500 to 5100. ' The most preferred polyols are polyethers which are copolymers of ethylene oxide and propylene oxide glycolrin or trimethylolpropane. Included with this group are the polymer graft dispersions previously described. Any suitable catalyst can be used including tertiary amines, such as triethylene diamine, N-methylmorpholine, N-ethylmorpholine, diethylethanolamine, N-co-morpholine, l-methyl-4-dimethylaminoethylpiperazine, methoxypropyl dimethylamine, N, N, N '-trimethylisopril propylene diamine, 3-diethylaminopropyldiethylamine , dimethyl benzylamine and the like. Other suitable catalysts are, for example, dibutyltin dilaurate, D / dibutyltin acetate [sic], stannous chloride, dibutyltin di-2-ethylhexanoate, stannous oxide, available under the trademark FOMREZ®, as well as other organometallic compounds such as those described in U.S. Patent No. 2,846,408. In the present invention it is possible to use an alcohol having from about 10 to about 20 carbons or mixtures thereof. Alcohols of this type are known to those skilled in the art. The types of alcohols contemplated are commonly produced through the oxo process and are known as oxo-alcohols. Examples of some products available commercially include LIAL 125 from Chemica Augusta Spa. Or NEODOL® 25 produced by Shell. These alcohols are known to improve crosslinking, improving the resistance to tearing by i- Aze. Although surface active agents are generally not necessary to solubilize the blowing agents of the present invention, contrary to other known blowing agents, the surface active agents, ie the surfactants, can be used, for example, to control the size and cell structure of the resulting foams. Common examples of these surface active agents include siloxane oxyalkylene ether polymers and other organic polysiloxanes, oxyethylated alkylphenol, oxyethylated fatty alcohols, fluoroaliphatic polymeric esters, paraffin oils, castor oil ester, ricindole [sic] esters and turkey red oil , as well as regulators of cells such as paraffins.

Chain extender agents that can be employed in the present invention include those having two functional groups carrying active hydrogen atoms. A preferred group of chain extender agents includes ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, or 1,4-butanediol and mixtures thereof. The additives that can be used in the process of the present invention include antioxidants, pigments known as carbon black, dyes and flame retardants (eg, tris-chloro ethyl phosphates or ammonium phosphate or polyphosphate), anti-aging stabilizers and weathering, plasticizers such as butyl-lactone range, fungistatic and bacteriostatic substances and fillers. The blowing agent of the present invention includes a non-chlorinated pentafluoropropane compound, specifically 1, 1,3,3-pentafluoropropane, otherwise known as HFA-245A. The pentafluoropropane blowing agent is used alone or in combination with water in sufficient amounts to provide the desired foam density. Depending on the amount of water used as the co-blowing agent and the package factor of the molded component, the amount of non-chlorinated pentafluoropropane blowing agent will generally be in the range of about 0.5 pep to about 10 pep, and more preferably from about 1.0 to 8.0 p.w. based on a total of 110 parts by weight of the resin for foams having densities of the molded part from 2 pcf to about 40 pcf. By way of non-limiting example, the amount of pentafluoropropane that is used as the sole blowing agent for a shoe sole or the like will generally be in the range from about 1.5 pep to about 5.0 pep for foams having densities molded from 25 pcf at approximately 35 pcf in a molded package factor of 1.5-3.0. By way of another example, the amount of pentafluoropropane that is used as a single blowing agent for a steering wheel will generally be in the range of about 2.0 pep to about 8.0 pep for foams having molded densities from 25 pcf to about 35 pcf with a package factor of 2.0-6.0. When water is added as a co-blowing agent, the amount of the non-chlorinated pentafluor blowing agent is reduced proportionally. In general, up to about 0.25 pbw of water may be employed as a co-blowing agent, and more preferably between about 0.05 pbw to about 0.17 pbw based on a total of 110 pbw of the resin. The mechanical parameters of the present process are flexible and depend on the final application of the polyurethane foam with integrated coating. The reaction system is very versatile and can be prepared in a variety of densities and hardnesses. The system can be introduced into a mold in a variety of ways known to those skilled in the art. It can be introduced in a closed mold preheated by the technique of injection at high pressure. In this way, it is processed well enough to fill complex molds at low mold densities (from 19 pcf to 25 pcf). It can also function using a conventional open mold technique, wherein the reaction mixture with system is emptied or injected at relatively low pressure or atmospheric pressure in a preheated open mold. or process of the present, the system can be run at mold temperatures from about room temperature to about 120 ° F with room temperature being preferred. Having thus described the invention, the following examples are given by way of illustration, wherein the amounts are given in parts by weight unless otherwise indicated. Density ASTM D-1622 Torn ASTM D-1938 Tensile Strength Tear Tough ASTM D42 ASTM D-412 matrix C Tensile Elongation Shore Hardness ASTM D-2240 ASTM D-412, matrix A Abrasion Taber ASTM 1044 Flexion ASTM 1052 Ross Polyol A is a polyoxyethylene polyoxyethylene block copolymer initiated with propylene glycol having a hydroxyl number of about 25 and a molecular weight of about 3850.

Polyol B contains 31% solids, graft copolymer acrylonitrile: styrene 1: 1, dispersed in a polyoxypropylene-polyoxyethylene block copolymer initiated by trimethylolpropane having a molecular weight of about 4120. The dispersion of the graft polymer has a hydroxyl number of about 25. Polyol C is a polyoxypropylene-polyoxyethylene block copolymer initiated with glycerin having a hydroxyl number of about 27 and a molecular weight of about 5050. XFE-1028 is an amine catalyst containing a patented mixture available from Air Products. T-12 is dibutyltin dilaurate. S-25 is a catalyst -amine that contains a patented mixture available from Air Products. WB 3092 is a prepolymer prepared from isocyanate modified with uretonimine and propylene glycol having an NCO content of 24% by weight and a viscosity of 120 cps at 25 ° C.

CFC-11 is 1-fluoro-1,1,1-trichloromethane. HFA-245fa is 1, 1, 1, 3, 3-pentafluoropropane HCF-134a is 1,1,1,2-tetrafluoroethane. Iso A is a 50/50% by weight mixture free of diphenylmethane diisocyanate solvents and urethane-modified polymethylene polyphenylene polyisocyanate prepolymer, wherein the mixture has an isocyanate content of 23% by weight.

Table 1 Foam formulations Initially it should be noted that the blowing agent was added in amounts to produce similar densities without rise for all solvent-blown foams to ensure similar paging factors so that the thickness of the coating was caused only by the condensation of the blowing agent on the surface of the mold. As will be understood by those skilled in the art, the phrase "pack factor" is the ratio of density without rise to the molded density of the resulting foam. The resin systems were foamed with the blowing agents added so that a master batch of resin was produced by combining all the components except the blowing agent. The Karl Fisher method for the determination of water was made and the residual water was determined in 0.20%. This value was used to determine all resin / prepolymer ratios. The liquid blowing agents (CFC-11 and HFA-245fa) were added to the resin system and then mixed. The blowing agent was added until a constant amount of the blowing agent was obtained after mixing. The gaseous blowing agent (HFC-134a) was added to 2000 g of resin through a gas dispersion tube (Pyrex 20C) of a pressurized cylinder (supplied by DuPont) equipped with a gas controller. The resin was loaded into a round-bottom, three-necked flask. The resin was kept cool by placing the flask in an ice water bath while the addition was carried out so that higher levels of HFC-124a could be added before saturation. A metallic stirring arrow connected to a motor kept the resin under stirring at approximately 500 rpm. The third segment of the round base was connected to a cold finger [sic] with dry ice / isopropyl alcohol to carry out the reflux of the blowing agent. The cold finger was equipped with a bubbler to regulate the flow of gas. The addition was timed and the final weight of the blowing agent obtained by measuring the change in weight of the flask. The total percentage of the blowing agent in the resin was then calculated. The water was also tested as a blowing agent by adding it directly to the resin and a water determination was carried out by Karl Fisher. Each of the blowing agent compositions in the resin were added directly to a quarter gallon Lily cup for foaming. Sufficient of the resin / blowing agent composition was added to produce the foam that flowed over the rim of the one-quart cup so that no-rise densities could be measured. The appropriate amount of the prepolymer was weighed directly into the Lily cup. The mixture was then stirred for 7 seconds with a 3-inch Vorath mixing blade at 200 rpm. The formation of the cream was observed, gel, top of the cup, rise times and no stickiness of the foam. The net weight of the foam produced was taken and the density of the foam was calculated: g x 0.059 = lb / ft3. The resulting no-rise foam densities and reactivity profiles are given in Table II Table II Reactivities and densities without rise The components of the foam were weighed so that the final total weight is equal to the weight needed in the mold plus about 50 g hanging in the Lily cup. The density of the desired molded plate is 30 lb / ft3 (0.48 g / cc). After agitation, the foam was emptied into a 12-inch by 6-inch by 3/8-inch aluminum mold heated to 120 ° F, which had been lightly sprayed with silicone mold separator. After 4 minutes, the plate was demolded and trimmed. The net weight of the plate was taken and the density of the foam was calculated (g / 442 ce = g / ml). After a one-week curing time, the physical properties were tested as reported in Table III below. As shown in Table III, the formation time of the HFA-245fa cream is slightly faster than that of the CFC-11 but not as fast as R-134a. This is probably due to the boiling point of HFA-245fa which is between CFC-11 and HFC-134a. Due to volatility, HFA-245fa (boiling point = 15.3 ° C) escapes from the resin faster than CFC-11 (boiling point 23.8 ° C) but not as fast as HFC-134a (boiling point 26.5) ° C). It can be deduced that HFA-245fa is, therefore, more soluble in the resin matrix than HFC-134a, but not as soluble as CFC-11. The solubility studies were not carried out due to the limited availability of HFA-245fa. The formation time of the reported cream of HFC-134a is not the actual cream but a foaming of the resin caused by the boiling of the blowing agent. It is considered that the slightly faster HFA cream. '' 45fa compared to CFC-11 is due to the same boiling effect but to a much lesser degree than HFC-134a. On a molar basis, HFA-245fa appears to be a more efficient blowing agent than CFC-11. At density without lower rise (or lb / ft3). The HFA-245fa is not as efficient a blowing agent as HFC-134a, but it is an equally efficient blowing agent as HFC-134a at density, no rise, higher than 12.5 lb / ftJ. When comparing the parts of the blowing agent necessary to produce a density without desired rise, HFA-245fa is a more efficient blowing agent than CFC-11 at densities of 9.0 and 12.5 lb / ft'5. When comparing the blowing efficiency with HFC-134a, it can be seen that more blowing agent is required for 9.0 lb / ft3 and 12.5 lb / ft3. However, the cost associated with the additional volume is considered more than displaced, eliminating the need for specialized transfer and storage equipment, especially at higher temperatures. At density with no higher rise, namely 12.5 lb / ft3, HFA-245fa produces superior tensile strength and tear strength for foams blown with HFC-134a (see Table III). The properties of the foam blown with HFA-245fa are only slightly lower than foams blown with CFC-11 with the exception of elongations and lower abrasion resistance. The abrasion resistance for foam for HFA-245fa (loss of 104 mg) is still good under industry standards of losses less than 200 mg. It is considered that the Ross flexural modulus slightly lower than this density without rise is not indicative of weaker bending properties but instead is due to a separation in the hand-mixed foam. At the no-rise density of 9 lb / ftJ, traction and elongations are superior to those of foams blown with CFC-11 and the other physical properties are equal. Again, the properties of the foam blown with HFA-245fa are much higher than those of the foams blown with HFC-134a. The hardness of the foams blown with HFA-245fa is similar to those of foams blown with CFC-11. Foams blown with CFC-134a tend to be softer. As expected, all solvent blowing agents produced foams with physical properties superior to those of water blown foams. This is especially shown in tear resistance. Water-blown foams used for comparison had no-rise densities of 16.5 lb / ft3 and 12.5 lb / ft3, respectively. The density with no higher rise (16.5 lb / ft3) was used due to the ease of handling and does not overflow the mold or produce flow lines in the final parts. The density with no lower rise (12.5 lb / ft3) was used as a comparison since the highest package factor could be obtained in a water-blown formulation. The foams blown with HFC-245fa produce a well defined thick coating, as determined by electronic scanning microscopy (EBM). The thicknesses of the coating were not quantitatively measured due to the high variability in the formation of the coating of the plates mixed by hand. In comparison, it can be seen that, in both densities without rises of 9 lb / ft3 and 12.5 lb / ft3, • foams blown with HFC-245fa have coating thicknesses approximately equal to foams blown with CFC-11. The coatings produced with HFC-245fa are much superior to those foams blown with HFC-134a. Due to its high volatility, HFC-134a does not produce a foam with thick coating. As expected, the water presented a very unrealistic coating since no condensation was carried out on the surface of the mold. When used in an integrated coating system, HFC-245fa produces foam with physical properties and coating thickness higher than foams blown with HFC-134a. When comparing blown foams with HFC-245fa and foams blown with CFC-11, foams produced with HFC-245fa compete with foams blown with CFC-11 both in the physical properties and in the thickness of the coating. In practice, it is considered • that the use of HFC-245fa is an improvement over HFC-134a, since it is easier to handle, does not require special equipment for gas management and produces foam with excellent physical properties and thickness of the coating. In addition, foams employing HFC-245fa as a blowing agent, and particularly foams with integrated coating, can be used to form articles having a relatively broad mold density, i.e., from about 2.0 pcf to about 40.0 pcf. Although it will be evident that the preferred embodiments of the invention described are well calculated to meet the aforementioned objectives, it will be appreciated that the invention is susceptible to modification, variation and change without departing from the spirit and the spirit.

Claims (19)

1. CLAIMS 1. A polyurethane foam with integrated coating consisting of the reaction product of: a) a polyisocyanate component; and b) an active hydroxy-functional polyol composition; in the presence of: c) a blowing agent including a non-chlorinated pentafluropropane and, optionally, water; d) a catalyst; and e) optionally one or more compounds that are selected from the group consisting essentially of: chain extenders, a surfactant, an alcohol having from 10 to 20 carbon atoms, fillers, pigments, antioxidants, stabilizers and mixtures thereof .
2. 2. The foam with integrated coating as recited in claim 1, wherein the non-chlorinated pentafluoropropane is present in an amount from about 0.5 to about 10.0 parts by weight, based on 110 parts by weight of b) -e).
3. 3. The foam with integrated coating as recited in claim 1, wherein the non-chlorinated pentafluoropropane blowing agent is 1,1,1,3,3-pentafluoropropane.
4. 4. The foam with integrated coating, as mentioned in claim 1, wherein the blowing agent includes water in an amount of up to about 0.25% parts by weight based on 110 parts by weight of b) -e). The foam with integrated coating as recited in claim 1, wherein the water is present in an amount from about 0.05 parts by weight to about 0.17 parts by weight, based on 110 parts by weight of b) -e) . 6. The foam with integrated coating, as mentioned in claim 1, wherein the active hydroxy-functional polyol composition is selected from the group consisting of polyoxyalkylene polyether polyols, polyoxylethane polyether dispersions grafted with vinyl polymer and mixtures thereof . The foam with integrated coating, as mentioned in claim 6, wherein the active hydroxy-functional polyol composition is present in an amount of between about 50 parts by weight to about 95 parts by weight, based on 110 parts on weight of b) - e). 8. The foam with integrated coating, as mentioned in claim 1, wherein the chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol and mixtures thereof. 9. The foam with integrated coating, as mentioned in claim 1, wherein the alcohol containing 10 to 20 carbon atoms is an aliphatic alcohol. 10. A polyurethane molded article with an integrated coating having improved flexibility and resistance to abrasion which is obtained by: a) providing an organic polyisocyanate; b) providing a resin containing: i) an active hydroxy-functional polyol composition; ii) a blowing agent including a non-chlorinated pentafluropropane and, optionally, water; iii) a catalyst; and iv) optionally one or more compounds that are selected from the group consisting essentially of chain extenders, a surfactant, an alcohol having from 10 to 20 carbon atoms, fillers, pigments, antioxidants, stabilizers and mixtures thereof . C) introducing components a) and b) into a mold and reacting the components for a sufficient period of time to produce a molded polyurethane article with an integrated coating. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the non-chlorinated pentafluoropropane is present in an amount of from about 0.5 parts by weight to about 10.0 parts by weight, based on 110 parts by weight of b) -e). 12. The polyurethane article with integrated coating, as mentioned in claim 11, wherein the non-chlorinated pentafluoropropane blowing agent is 1,1,1,3,3-pentafluoropropane. 13. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the blowing agent includes water in an amount of up to about 0.05 parts by weight up to 0.17% in parts by weight, based on 110 parts by weight of b) -e). 14. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the active hydroxy-functional polyol composition is selected from the group consisting of polyoxyalkylene polyether polyols, polyoxylethane polyether dispersions grafted with vinyl polymer and mixtures thereof. 15. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the active hydroxy-functional polyol composition is present in an amount of from about 50 parts by weight to about 95 parts by weight, based on 110 parts by weight of b) - e). 16. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the chain extender is selected from the group consisting of ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butanediol and mixtures thereof. 17. The polyurethane article with integrated coating, as mentioned in claim 10, wherein the alcohol containing from 10 to 20 carbon atoms is an aliphatic alcohol. 18. An article formed from the composition of claim 10, wherein the article has a density of the molded part from about 2.0 pcf to about 40.0 pcf. 19. The article of claim 10, wherein the article is a shoe sole.