MXPA97003469A - Polyurethanes resistant to manc - Google Patents

Abstract

The present invention relates to polyurethanes, and more particularly, stain resistant polyurethanes that are hydrophobic in nature that are useful for various commercial applications. An added feature of the present invention is that the stain resistant polyurethanes can be made to a hardness desired

Description

POLYURETHANES RESISTANT TO SPOTS FIELD OF THE INVENTION The present invention relates to stain-resistant polyurethanes, and more particularly, to polyurethane-based elastomers resistant to stains, foams and coatings.

BACKGROUND OF THE INVENTION Polyurethanes have become increasingly useful for a wide range of commercial applications. These materials are generally characterized by mechanical properties and resistance to degradation caused by heat oxidation, ozone attack or ultraviolet radiation surprising. Frequently the polyurons are less expensive to process than rubber and thermoplastics making them highly desirable for use in the industry. Although many compositions based on p-Lurethane are known, a perceived disadvantage of the known materials resides in their susceptibility to staining, i.e., discoloration due to the absorption of water-soluble materials, for example, urethane-based elastomers. employees such as protective and / or decorative edges for furniture and upper parts of appliances tend to be discolored during the time when they are spilled on the same fluids such as coffee and tea, among others. In this way, there is a need for urethane ballasting and foams that have surprising mechanical properties, are resistant to degradation and are resistant to stains.

SUMMARY OF THE INVENTION According to a preferred embodiment, the present invention relates to manure-resistant polyurethanes formed as the reaction product of a mixture comprising a) an organic isocyanate; b) a hydrophobic compound selected from the group consisting of hydrophobic compounds having at least two isocyanate reactive hydrogens, hydrophobic long chain drocarbides and mixtures thereof; c) optionally, when b) includes less than sufficient isocyanate-reactive hydrogen to form polyurethane, at least one second compound that is sufficiently reactive with the organic isocyanate to form a polyurate; and d) optionally, one or more components selected from the group consisting of blowing agents, ticulators, catalysts, antioxidants, UV stabilizers, flame retardants, water scavengers, multipliers, fillers, coloring agents and mixture of the same. Under an alternative preferred embodiment, the invention relates to stain resistant polyurethane formed as the reaction product of a mixture comprising: a) an organic isocyanate; b) at least one hydrophobic compound capable of reacting with the organic isocyanate to form a polyuret, the compound having at least two hydrogens reactive with isocyanate; and c) optionally, one or more components selected from the group consisting of blowing agents, ticulators, catalysts, antioxidants, UV stabilizers, flame retardants, water scavengers, plastifiers, fillers, coloring agents and mixtures. thereof. Stain-resistant polyurethanes can be used for a number of different products including, but not limited to, countertop furniture and edges, appliance handles, shelf edges and decorative moldings, for example. In general, it is contemplated that the polyurethane compositions of the present invention may be employed under any application where the stain resistance is a consideration. In addition to the stain-resistant urethane compositions, the present invention also relates to the formation of prepolymers which are storage stable and easily useful for the formation of various polyurethane products. A unique aspect of the urethane resis tant compositions is that the ores-tte invention can be modified so that the resulting product has the desired hardness e.g., varying from Shore A to Shore D after the cured. The present invention also relates to the method for preparing both the stain resistant polyurethanes and the prepolymers of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED MODE The stain-resistant polyurethanes of the present invention can be used to form a variety of products, including, but not limited to, furniture edges and countertop parts, appliance handles, shelf edges. and decorative moldings, among others. In general, it is contemplated that the preferred urethanes of the present invention may be employed in the production of various products wherein stain resistance is of particular importance. As used herein, the phrase "stain resisting polyurethanes" should be understood to include both filled and unfilled filler-based polyurethane compositions, including, generally, foamed elastomers and coatings. Hydrophobic compounds having at least one of isocyanate-reactive hydrogens which are considered useful, without limitation, in accordance with the teachings of the present invention, include polyols having a carbon chain length of at least about C1Q or greater. Preferred pyrolines of said polyols include castor oil, co-bases or derivatives of castor oil, polybutadiene and saturated hydrocarbon polyols. By hydrocarbon polyols saturated bureau is implied that the polyols have no double bond in their molecular structure. In what was mentioned above, kidney oils are considered to be particularly preferred. While numerous commercially available castor oil products are useful in accordance with the teachings of the present invention, one known as DB Oil which is available from CasChem, Inc., of Bayonne, NJ, has been found to be particulate useful mind. In this regard, it has been observed that rye oil does not only appear to improve the hydrophobicity of polyurethane compositions, i.e., resistance to water-soluble staining materials such as coffee and tea, for example, without also improving the fire retardant characteristics of the resulting product due to the formation of coke caused by the relatively long hydrocarbon chain length. Under certain applications, the hydrophobic compound optionally or alternatively employed or will be included as will have at least two hydrogens reactive with isocyanate, said compounds being referred to herein as long chain hydrocarbons. Examples of such long chain hydrocarbons include, for example, and without pretending to be mitigatives, paraffins, olefins, vegetable and animal oils and materials dichso mifications. Particularly useful are the so-called long-chain hydrocarbons, the hydrocarbon oils and the monofunctional long-chain hydrocarbon compounds such as alcohols, and / or fatty acids (long-chain hydrocarbon) and the fine powders. By long chain hydrocarbons, it is meant that the hydrocarbons will have a carbon chain length of at least C1Q, more preferably at least C12, still more preferably, at least C1g, and still more preferably, they will have a carbon chain length of C, fi or greater. In general, the longer the chain length of the hydrocarbon is, the more hydrophobic the hydrocarbon will be in nature. It should be noted that the amount of hydrophobic compound employed will depend largely on the desired application for the final product. For example, while high amounts of castor oil will generally result in products that have the best stain resistant characteristics, the resulting polyurethane-based product may be too soft for certain applications. Therefore, the dilution of castor oil or other of these hydrophobic compounds with less hydrophobic polyols, chain extenders, crosslinkers and other additives will give rise to products that are typically less resistant to stains. In this way, the amount of hydrophobic compound employed in the stain resistant polyurethane composition will determine a large number of factors including the end use of the product, as a minimum, the preferred stain resistant polyurides of the present invention will generally include when less about 10 weight percent of a hydrophobic compound based on the total weight of the composition prior to reaction with the organic isocyanate. In addition to the hydrophobic compound, the polyurethane-based compositions of the present invention may optionally employ one or more conventional additive components at the levels of the described branch selected from the group consisting of chain extenders, crosslinkers, catalysts, antioxidants, UV stabilizers, flame retardants, water barriers, fillers, coloring agents and mixtures of the same. Suitable examples of useful chain extenders in the stain resistant urethanes of the present invention include polyoxyalkylene polyether polyols which are the polymerization product of an alkylene oxide with a polyhydric alcohol. Suitable polyhydric alcohols include those described above for use in the preparation of the hydroxy-terminated polyesters. Any suitable alkylene oxide and mixtures thereof may be used such as ethylene oxide, propylene oxide, butylene oxide, amyl oxide, and mixtures of these oxides, preferably propylene oxide. The polyether polyols of polyoxypropylene are more hydrophobic than their ethylene oxide counterparts. The polyalkylene polyol 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 rhodium oxide. The polyether polyols of polyalkylene can have hydroxyl groups either primary or secondary. Included among the polyether polyols are polyoxyethylene glycol, poly oxypropylene glycol, polyoxybutylene glycol, polytetramethyl glycol, block copolymers, for example, polyoxypropylene and polyoxyethylene blends, pol-1, 2. Oxibuti-wood and polyoxyethylenglycol, poly-1, 4-tetramethyl and polyoxyethylene glycols, and copolymer glycols prepared from mixtures or addition of two or more alkylene oxides. The p-alkylene polyether polyols can be prepared by any known process such as, for example, the process described in the Encyclopedia of Chemical Technology, Vol. 7, p. 257-262, published by Inter Science Publishers, Inc. (1951) or in U.S. Patent No. 1,922,459; all of which are expressly incorporated herein by reference. Extensive lists of suitable polyol can be found in columns 2 and 3 of U.S. Patent No. 3,652,639; columns 2-6 of the United States Patent No. 4,421,872; and columns 4-6 of U.S. Patent No. 4,310,643, these three patents being incorporated herein by reference. The polyether polyols generally employed will have preferred molecular weights of from 500 to 10,000, more preferably from 750, to 8,000, and still more preferable from 1,000 to 6,000. Even though polyester polyols are generally less preferred than polyols of polyether in that they tend to be less soluble than polyether polyols, polyester polyols can also be employed. Suitable hydroxy-terminated polyesters include those obtained, for example, from polycarboxylic acids and polyhydric alcohols. A suitable polycarboxylic acid can be used such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, bacic acid, brasilic acid, tapsic acid, maleic acid, fur rich acid , glutaconic acid, α-hydromuconic acid, B-hydromuic acid, α-buty 1-a-1-glutaric acid, a, Bd i and i lsuccinic acid isophthalic acid, terephthalic acid, phthalic acid, hemimetic acid and 1,4-cyclohexanedicarboxylic acid. Mixtures can also be used. An appropriate polyhydric alcohol can be used such as ethylene glycol, propylene glycol, trimethanol, 1,2-bu tandiol, 1,5-pentanediol, 1,6-hexanediol, 1,7-heptanediol, 2-methyl 1 , 3-propanediol, hydroquinone, resorcinol, glycerol, glycerin, 1, 1, 1 -trimeti loletane, 1, 2,6-hexantriol, α-methyglucoside, sucrose and sorbitol. Again, mixtures of said to cools may be employed. Also included within the term "polyhydric alcohol" as used herein, are flon-derived compounds such as 2,2-b s (4-hydroxypheni-1) -propanol, commonly known as Bisphenol A. The polyols of polyester, if employed, will preferably have molecular weights of from 500 to 10,000, more preferably from 750 to 8000, and even more preferably from 1000 to 6000. Preferred chain extenders will have molecular weights of from 50 to 400 generally and preferably from 60 to 300 In order to obtain the desired hardness of the polyurethanes, the amount of hydrophobic component which has at least two isocyanate-reactive hydrologens to chain extenders can be varied within a relatively broad molecular relationship; hardness typically increasing with increasing content of former chain tenders. For example, less rigid polyurethanes (which have a Shore A hardness of less than 95, preferably d 75 to 85 after curing), will generally have hydrophobic component linkages to chain extenders of 10: to 20: 1 , preferably from 8: 1 to 15: 1. For more rigid polyurethanes, (for example, those having a Shore D hardness of more than 50, preferably 60 to 80 Shore D, after curing), the molar ratios of hydrophobic component to dena extenders are 2: 1 at 3: 1, preferably 4: 1 to 5: 1.

Suitable examples of crosslinkers useful in accordance with the practice of the present invention include, without limitation, the alkylene oxide addition products of trimethylolpropane, glycerin, sucrose, sorbitol, propylene glycol, dipropylene glycol, pentaerythritol and 2, 2-bis (4-hydroxypheni 1) -propane and mecías of them that have equivalent weights of 31-340. Catalysts may also be employed in accordance with the teachings of the present invention. The catalyst generally accelerates the reaction of the active hydrogen containing compounds (if present) with the organic polyisocyanates. Examples of useful catalysts include organic metal compound, preferably organic tin compounds such as tin (II) salts of organic carboxylic acids eg, tin (II) acetate, tin (II) octoact, ethylhexyl of tin (II) and tin laurate (II), as well as the dialkylino (IV) salts of organic carboxylic acids, e.g., dibutyltin diacete, dibutyltin maleate and dialytic diacetate. Specific examples of organic tin compounds that are useful include, without limitation, dibutyltin dilaurate, dibutyltin sulfide, and tin mercaptans, among others. Other organic metal compounds that are considered useful include zinc compounds such as zinc octoate with bismuth compounds. Useful organometallic compounds as catalysts are generally described in U.S. Patent No. 2,846,408, incorporated herein by referendum. The organic metal compounds are used alone or in combination in combination with strong basic amines. Examples include idines such as 2, 3-dimeti 1-3, 4, 5,5-tetrahydropyrimine, tertiary amines such as triethyl sheet, tributyl sheet, dimethylbenzyl amine, N-methyl orfolin, N- eti Imorfol ina, N-cyclohexylmorpholine, N, N, N ', N' -tetramethylethylenediamine, N, N, N ', N'-tetramethyl-lbutanediamine, pentamethylethiatriamine, tetramethyldiaminoethyl ester, bis (dimethyl aminopropyl) ) urea, dimethylpiperazine, 1,2-dimethyl-1-imidazole, 1-aza-bicyclo (3.3.30) octane and preferably 1,4-diazabicyclo (2.2.2) octane, 1,8-diazabicyclo 5, 4, 0- undecene 7 and alkanolamine compounds such as tretinoamine, triisopr panolamine, N-methyl- and N-eti Id ietanola ina and dimet i letanolamine. Suitable catalysts also include trisidia qu i lamino) -s-hexahydrotriazines, especially tris (N, N-di me i 1 aminopropi 1) -s-hexahydrotriazine, tetraalkylammonium hydroxides such as tetramethyl ammonium hydroxide, alkali hydroxides such as sodium hydroxide and alkali alcoholates such as sodium m-tilate and ptoasium isopropylate as well as alkali salts of long-chain fatty acids with 10 to 20 carbons and optionally OH-side groups. An effective amount of catalyst to promote the reaction of isocyanate groups with the polyol or with other isocyanate groups in the case of isocyanurates is employed. 0.001 to 5 weight percent, catalyst catalyst combination based on the weight of polyol composition is preferred. Mixtures of amine, tin and bismuth catalysts can be used. Antioxidants may also be used if necessary to retard the oxidation of the reacted urethane. It is preferred among the numerous commercially available antioxidants that are considered useful: Irganox, available from ciba-Geiby Corp. of Greensboro, N.C .; and Cyanox, available from Cytec, Industries Inc of Havre De Grace, MD; both are particularly useful. Tam-well can be mixed mixtures of antioxidants. UV stabilizers that can be used include without limit, benzophenones, benzotriazoles, acrylonitrols, phenol-nickel complexes and mixtures thereof. Examples of commercially available UV stabilizers include Tinuvin, available from ciba-Geigy Corp. of Greensboro, N.C., and Uvinul, available from GASF Corporation of Mt. Olive, NJ. It may be desirable in certain applications to employ one or more flame retardants. For example, certain flame retardants that are reactive with isocyanates that may be employed include phosphorus-based products such as Fyrol 6 and Fyrol 51, available from A zo Chemicals, Inc., of Chicago, IL.; and Vircol 82 available from Mobil Chemical Co., of Norwalk, CT. Additionally, certain halogen-based flame retardants, such as FR-522 and Saytex FR-1138 (which are di-bropentin-based products available from AmeriBrom, Inc. and Ethyl Corporation of Richmond, VA, respectively) can be used. Still other flame retardants that are generally non-reactive to isocyanates can be employed. Reactive FR series flame retardants are preferred since they are homogeneous in nature, ie they do not migrate to the surface of the polyurethanes Mixtures can also be used. For non-foaming applications, water scavengers, otherwise designated herein as water absorbing agents, may be employed so that any water contained in the composition is prevented from reacting with the isocyanates which in turn prevents the formation of C0. and this limits or prevents foaming. Molecular sieves that are generally based on silica have proved useful in this regard. Additionally, Zolidine, which is a liquid oxazolidine available from Angus Chemicals, Inc. of Buffalo Grove, IL, is contemplated as being useful. For applications where the polyurethanes resistant to the spots of the present invention are foams, blowing agents are typically required. Suitable blowing agents are those of the reactive type such as water, formic acid or tertiary alcohols; physically active blowing agents having a boiling point below 28 degrees C and vaporizing at or below the temperature of the foam mass comprising chlorofluorocarbons having at least hydrogen (mild CACs) and volatile hydrocarbons , or mixtures thereof. Soft CFCs in the present are those that have an ozone depletion potential of less than 0.2, including 1, 1, 1-trichloroethane, 1, 1, 2, 2-tetraf-lutein, HCFC-14 HCFC-22, HCFC - 123 and HCFC-142b. Volatile hydrocarbons include butane, pentane, hexane, heptane, cyclopentane, cyclohexane, pentene and heptene. A surfactant is generally necessary for the production of high-grade polyurethane foam in accordance with the present invention, since in the absence thereof, the foams can be knocked down. Examples of surfactants include compounds that support the homogenization of the starting materials and optionally are also suitable for regulating the cell structure. An extensive array of surfactant substances in accordance with the teachings of the present invention is described in United States Patent No. 5,045,885 to Sa para et al., Which is expressly incorporated herein by reference. Other conventional additives that include, but are not limited to, astif icants, reactive and non-reactive silicone oils, fillers and coloring agents including dyes and pigments can also be employed, at conventional levels or described in the art. Included in the class of additive materials generally referred to herein as fillers are fibrous and particulate materials, non-polar polyester materials, inorganic antiblocking agents. Examples of these materials include glass and carbon fibers, silicas, calcium carbonate, clay, mica, talc, carbon black, particulate graphite, and flakes and talas, among others. For further understanding of the various optional components that may be employed, reference may be made to various technical publications including, for example, the article by J.H. Saunders and K.C. Frisch, High Polymers, Volume XVI, Polyurethane, Parts 1 and 2 (Interscience Publishers 1962 and 1964), Kunstostoff -Handbuch, Volume 7, Polyurethan 1a and 2a. editions (Cari hanser Verlag, 1966 and 1994) or DE-A 29 01 774 that are expressly incorporated herein by reference. As alluded to above, the hydrophobic components of the present invention are particularly useful when mixed with certain isocyanate compounds. Among the many isocyanates, otherwise referred to herein as organo cyanates, which are considered useful are those which include aromatic, aliphatic and cycloaliphatic polyisocyanates and combinations thereof. Examples of these isocyanates can be found in columns 8 and 9 of US Pat. No. 4,690,956, incorporated herein by reference. Representative polyisocyanates are diisocyanates such as m-phenylene diisocyanate, 2,4-toluene diisocyanate, 2,6-toluene diisocyanate, mixtures of 2,4- and 2,6-toluene diisocyanate, diisocyanate of hexameti wood, diiso cyanate of tetramethyl wood, diisocyanate of cyclohexane-1,4, diisocyanate cyanate of hexahydrotoluene (and isomers), naphthalene-1,5-diisocyanate, 1-methi lfeni 1-2, 4-di isocyanate, 4,4'-diisocyanate-diphenyl diisocyanate, 4,4'-diisocyanate-bifennylane, 3,3'-dime-toxy-4,4'-biphenium, diisocyanate, 3'3-diimcyanate -dimeti 1-4 , 4 '-bifeni lo and 3, 3' -dimeti ldifeni lmetano-4, 4 '-di isocyanate; the tri isocyanates such as tri-socianate of 4, 4, 4-trifluoromethane and 2,4,6-triisocyanate of toluene, and the tetraisocyanates such as 4,4'-dimethyl-1-diphenyl-2-methane. '5, 5' -tetrai soc ianato and po lomeric isolations such as polymethylene polyisocyanate polyphenylene, mixtures of the same.For the preparation of the stain-resistant polyurethanes of the invention, the The ratio of the equivalent weight number of NCO groups of isocyanate (a) to the sum of hydroxyl groups of compound (b) is from 300: 100 to 95: 100, preferably from 105: 100 to 100: 100. equivalent, the weight of an element that is chemically combined with 8 grams of oxygen or its equivalent is implied, for example, since 8 grams of oxygen is combined with 1,008 grams of hydrogen, the latter is considered equivalent to 8 grams of oxygen Appropriate methods for preparing the stain resistant polyurethanes of the present invention include adding the hydrophobic compound to a container and heating to approximately 60 ° C. Next, each of the other components, including one or more co-selected from the group consisting of chain extenders, crosslinkers, catchers, antioxidants, UV stabilizers, falma retarders, astif icants, fillers, coloring agents and mixtures thereof, with the exception of any water scavengers, are charged to the mixing vessel and mixed with the hydrophobic compound. After mixing, the water level of the composition is typically measured to determine if the water level is less than approximately 0.035 by weight, based on the total weight of the composition. If the water is higher than that level, the composition is further heated under vacuum to expel the water; however, if the water level is at or below this level, a water scavenger is added to the mixture with mixing. During the complete mixing of the components, a resinous material results. Next, the resin is mixed with the organic isocyanate to form the stain resistant polyurethane of the present invention. as discussed by way of non-limiting examples below. Other conventional methods or methods described in the art can also be used to prepare the resins and prepolymers of the present invention.

EXAMPLE 1 A stain resistant polyurethane was prepared in accordance with the teachings of the present invention, first charging 85.7% by weight of DB oil to a dry, clean mixing tank equipped with a dry air or nitrogen purge. The DB oil was heated to 60 ° C and then 10.0% by weight of FR-522, 0.5% by weight of Tinuvin 328, 0.5% by weight of Tinuvin T765, 0.55 by weight of Irganox 245 and 0.3% by weight were slowly added. d Fomrez UL28 with DB oil mixing and the composition was mixed for one hour. The composition was mixed continuously until the water level was less than about 0.03% by weight at which time 2.5% by weight of a molecular sieve A-3 was added and the composition was mixed for approximately half an hour to form the desired resin , which was liquid and had a viscosity of approximately 700 cps and a density of 1.0 g / cc or 8.2 lbs / gal a25 * C. One hundred parts by weight of the resin were mixed with 45 parts by weight of dicyclohexy-limetane diisocyanate having a viscosity of about 30 cps and a density of 1.07 g / cc or 8.9 lbs / gal at 25 ° C and molded. The mold was maintained at a temperature of between about 54-66 ° C. As a result of the mixing of the resin and the isocyanate together and the molding thereof, an urethane-based elastomer product was obtained which is aliphatic, light-stable and sufficiently flame-retardant at a thickness of 12.7 millimeters to achieve a classification UL94V0. the resulting polyurethane product had a du za as measured by ASTM D2240 of 75, tear strength of 91.39 kg / cm in accordance with ASTM D412, elongation breakage of 200 and Severe Tear in accordance with AST D1004 of 10.16 joules.

EXAMPLE 2 A second malt resistant polyurethane was prepared by charging 39.15% by weight of DB Oil to a similar mixing tank and adding 17.5% by weight of dipropylenolyl with mixed do. The mixture was heated to 60 ° C. and then 0.2% by weight of Fo rez UL 28, 0.5% by weight of tinuvin 328, 0.5% by weight of Tinuvin T765, 0.5% by weight of Irganox 245 and 39.15% by weight of Pluracol were added. 726 and the composition was mixed until the water level was less than about 0.03% by weight at which time 2.5% by weight of an A-3 molecular sieve was added. The resulting composition was mixed for about a half hour with the resulting liquid resin having 2.5 wt.% Molecular sieve. A-3 was added after the water level was below a viscosity of approximately 700 cps and a density of 0.99 g / cc or 8.2 lgs / gal at 25QC. One hundred parts by weight of the resin were then mixed with 58 parts by weight of dicyclohexyl diisocyanate methane having a viscosity of approximately 30 cps and a density of 1.07 g / cc or 8.9 lbs / gal at 25eC and molded. The mold was maintained at a temperature between about 54-66 ° C. The resulting polyurethane product had a hardness as measured by ASTM D2240 of about 80-85, tensile strength d 147.63 kg / cm in accordance with ASTM D412, elongation at 230 ° C and Gravity Torn in accordance with ASTM D-1004 of 10.16 Jul ios.

EXAMPLE 3 EXAMPLE 3 A third polyurethane composition was prepared for purposes of comparing the man-resistant characteristics of a commercial product currently employed against that provided in accordance with the teachings of the present invention. This third example was prepared by charging 89.5 parts by weight of Pluracol 538 polyol commercially available from BASF Corporation to a 60SC mixing tank together with 9.0% by weight of diethyl glycol. The mixture was mixed under vacuum and nitrogen purge at a temperature between 82 to 100 ° C until the water level was below 0.05%. Then, the temperature was adjusted to between 49s to 60SC and 0.5% by weight of Tinuvin 328 was added with mixing. The mixture was mixed for approximately 25 minutes and cooled to between 21 to 38 ° C at which time 0.5% by weight of Tinuvin 765 and 0.5% by weight of Fomrez UL-32 catalyst was added and mixed for half an hour. The resultant resin that was liquid had a viscosity of 775 cps and a density of 1.03 g / cc or 8.6 lbs / gal at 255C. One hundred parts by weight of the resin were mixed with 43.5 parts by weight of poly ethylene polyisocyanate diisocyanate, a MDI prepolymer, having a% NC0 of 23, a viscosity of about 700 cps and a density of 1.2. g / cc or 10 lbs / gal at 255C. The mold was maintained at a temperature of approximately 54 ° C. The resulting polyurethane product had a hardness as measured by ASTM D2240 of approximately Shore 65 tensile strength of 44.29 kg / cm in accordance with AST D412, elongation at break of 190 and Severe Tear in accordance with ASTM D1004 of 3.39. joules To analyze stain resistance, a sample of each of Examples I, II and III was immersed in the same cavé solution and allowed to remain for a period of 24 hours. Then, each sample was separated and lightly rinse with a clean damp towel. Upon observing the samples, the samples were formed in accordance with the Examples and II showed virtually no signs of manging; in fret, the sample of Example III was clearly discolored As alluded to above, in addition to its use to prepare stain-resistant polyurethanes, the hydrophobic compound of the present invention can also be used in prep-lysers. In this regard, the hydrophobic resins, such as those described in Examples I and / or II above, are cleaved with the isocyanates and heated to the desired temperature while mixing. The NCO content of the mixture is exceeded during the reaction until the NCO s target percentage is obtained, at which time the composition is cooled to ambient, and to say room temperature. The prepolies formed conforming to the teachings of the present invention will generally have between about 1.0 to 32.0% NCO. While it will be apparent that the preferred embodiments of the invention described are well calculated to fill the manifest objects, it will be noted that the invention is susceptible to modification, variation and change without abandoning the spirit of the same.

Claims (33)

1. - A stain resistant polyurethane which is the reaction product of a mixture, comprising: a) an organic isocyanate; b) a hydrophobic compound selected from the group consisting of hydrophobic compounds having at least two hydrogens reactive with isocyanate, long chain hydrophobic hydrocarbons and mixtures thereof; c) optionally, when b) includes less than the isocyanate-reactive hydrogens sufficient to form a polyurethane, at least one second compound that is sufficiently reactive with the organic isocyanate to form a polyurethane; and d) optionally, one or more components selected from the group consisting of blowing agents, reactants, catalysts, antioxidants, UV stabilizers, flame retardants, water scavengers, plasticizers, fillers, coloring agents and mixtures of the same.

2.- The stain-resistant polyurethane of claim 1, wherein the hydrophobic compound has a carbon chain length of C.Q or longer.

3. The stain resistant polyurethane of claim 1, wherein the compound having at least two hydrogens reactive with isocyanate is a polyol.

4. The stain resistant polyurethane of claim 3, wherein the polyol is a castor oil.

5. The stain-resistant polyurethane of claim 1, wherein the component b) is present in an amount of at least 10.0% by weight based on the total weight of the composition.

6. - the stain-resistant polyurethane of claim 1, wherein the ratio of the weight number of NCO groups of component a) to the sum of group hydroxyl d component b) is from 300: 100 to 95: 100 .

7. The stain resistant polyurethane of claim 1, wherein the long chain hydrocarbon is selected from the group consisting of paraffins, olefins, animal oils, vegetable oils and mixtures thereof.

8.- the stain resistant polyurethane of claim 1, wherein the polyurethane is elastomeric.

9.- The stain-resistant polyurethane of claim 1, wherein the polyurethane is a foam.

10.- The stain resistant polyurethane of the vindication 1, wherein the component c) is a cade extender.

11.- A stain resistant polyurethane which is a reaction drug of a mixture, comprising: a) an organic isocyanate; b) at least one hydrophobic compound capable of reacting with the organic isocyanate, to form a polyurethane, the compound having at least two hydrogen reactive with isocyanate; and c) optionally, one or more components selected from the group consisting of blowing agents, reactants, catalysts, antioxidants, UV stabilizers, flame retardants, water scavengers, plasticizers, fillers, coloring agents and mixtures of the same.

12. The stain resistant polyurethane of claim 11, wherein the hydrophobic compound has a carbon chain length of C1Q or longer.

13.- The stain resistant polyurethane of claim 11, wherein the hydrophobic compound is a polyol.

14. The stain resistant polyurethane of claim 13, wherein the polyol is a castor oil.

15. The stain resistant polyurethane of claim 11, wherein component b) is present in an amount of at least 10.0% by weight based on the total weight of the composition.

16.- The stain resistant polyurethane of claim 11, wherein the ratio of weight number equivalent to NCO groups of component a) to the sum of hydroxyl group of component b) is 300: 100 to 95: 100

17. The stain resistant polyurethane of claim 11, wherein the compound b) further comprises a long chain hydrocarbon.

18.- The stain-resistant polyurethane of the re vindication 17, wherein the long chain hydrocarbon is selected from the group consisting of paraffins, olefins, animal oils, vegetable oils and mixtures thereof.

19.- The stain-resistant polyurethane of claim 11, wherein the polyurethane is elastomeric.

20.- The stain-resistant polyurethane of claim 11, wherein the polyurethane is a foam.

21.- A stain resistant polyurethane which is the reaction product of a mixture comprising: a) an organic isocyanate; and b) a resinous material comprising at least one hydrophobic com pound selected from the group consisting of compounds having at least two isocyanate-reactive hydrocarbons, long chain hydrocarbons and mixtures thereof, and optionally, one or more compounds selected from the group consisting of blowing agents, crosslinkers, antioxidant catalysts, UV stabilizers, flam retarders, water scavengers, plasticizers, fillers, coloring agents and mixtures thereof.

22. - The stain resistant polyurethane of the vindication 21, where the hydrophobic compound has a carbon chain length of C.Q or longer. 23.- The stain-resistant polyurethane of the claim 21, wherein the hydrophobic compound is a polyol. 24.- The stain resistant polyurethane of the vindication rej 23, where the polyol is a castor oil. 25. The stain-resistant polyurethane of claim 21, wherein component b) is present in an amount of at least 10.0% by weight based on the total weight of the composition. 26.- The stain-resistant polyurethane of the vindication 21, where the ratio of the equivalent weight number of group NCO of component a) to the sum of hydroxyl groups - of component b) is 300: 100 to 95: 100 27.- The stain-resistant polyurethane of the vindication 21, where the long-chain hydrocarbon is selected from the group consisting of paraffins, olefins, animal oils, vegetable oils and mixtures thereof. 28.- The stain resistant polyurethane of the vindication 21, where the polyurethane is elastomeric. 29.- The stain-resistant polyurethane of the vindication 21, where the polyurethane is a foam. 30. A prepolymer useful for the production of stain-resistant polyurethane, which comprises: a) a resin comprising a hydrophobic compound selected from the group consisting of compounds having at least two hydrogens reactive with isocyanate, long chain hydrocarbons and mixtures thereof, and optionally, one or more compounds are selected from the group consisting of blowing agent, crosslinkers, catalysts, antioxidant UV stabilizers, flame retardants, water scavengers, plasticizers , fillers, coloring agents and mixtures thereof; and b) an isocyanate mixed with the resin while being milled, wherein the resulting composition has the desired percentage of NCO. 31.- The prepolymer of claim 30, wherein the prepolymer has an NCO content of between about 1.0 to 32.0% NCO. 32.- A process for making polyurethanes resistant to stains comprising the steps of: a) providing a hydrophobic compound selected from the group consisting of compounds having at least two hydrogens reactive with isocyanate, long chain hydrocarbons and mixtures thereof same a reaction vessel and heat; b) optionally mixing in admixture with the component one or more compounds selected from the group consisting of blowing agents, crosslinkers, catchers, antioxidants, UV stabilizers, flame retardants, plasticizers, fillers, coloring agents and mixtures thereof and the resulting mixture is declared to expel excess water, if any; c) optionally adding a water scavenger to the mixture of a) and b) once it has been found that the water level is less than approximately 0.05% by weight; d) reacting the above mixture with an organic isocyanate to form a stain resistant polyurethane. 33.- A process for making a prepolymer useful for the production of stain resistant polyurethanes, comprising the steps of: a) forming a resin that comrpenses a hydrophobic compound selected from the group consisting of compounds that have at least two hydrogens reactive with isocyanate, long chain hydrocarbons and mixtures thereof, and optionally, one or more compounds selected from the group consisting of blowing agents, crosslinkers, catalysts, anti oxidants, UV stabilizers, retarders flam water sweepers, plasticizers, fillers, coloring agents and mixtures thereof; and b) mixing an organic isocyanate with the resin to form a prepolymer.