Abstract: A process for the manufacture of polyurethane foam comprising the steps of (i) mixing at a reaction index of 40 to 400: (a) a polyisocyanate blend comprising at least one polyisocyanate and optionally, additives and fillers; (b) a polyol blend comprising isocyanate reactive components and optionally, water, additional blowing agents, catalysts, surfactants, fillers and other additives; wherein either or both said polyisocyanate blend or said polyol blend contain between 0.3 to about 20 wt. % CO.sub.2 based on the total weight of said polyisocyanate blend and said polyol blend; (ii) introducing and uniformly mixing in liquid form of CO.sub.2 as a blowing agent into either or both said polyisocyanate blend or said polyol blend and maintaining said CO.sub.2 in said liquid form. The present invention also relates to an apparatus, which performs the above-mentioned process.

Abstract: This invention relates to a process for the production of polyurethane/urea elastomers from a reaction injection molding process of a reaction mixture on the presence of a catalyst via the one-shot process. The isocyanate component of this invention is a prepolymer based on a cycloaliphatic diisocyanate, and having an NCO content of 12-27%, an average isocyanate functionality of less than 2.3, a monomer content of greater than about 25% by weight, and containing urethane or urea groups. The isocyanate-reactive blend comprises a high molecular weight polyether polyol and a low molecular weight chain extender wherein the equivalent ratio of hydroxyl groups to amine groups of the chain extender is from 1:2 to 20:1. This invention also relates to the polyurethane/urea molded article produced by the above process.

Abstract: The present invention is directed to a heat resistant product prepared by reacting a) a mixture of i) an organic polyisocyanate, ii) an epoxide group containing compound, and iii), optionally, an organic compound containing an active methylene group and containing at least one electron withdrawing group adjacent to the methylene carbon, and b) at least one polyol which is free of any tertiary amine groups, with the reaction being conducted at an NCO:OH equivalent ratio of from 2:1 to 5:1. The reaction is conducted in the presence of a tertiary amine-free isocyanurate catalyst selected from the group consisting of oxides, alkoxides, hydroxides and carboxylates of alkali metals, alkaline earth metals, transition metals and quaternary ammonium.

Abstract: This invention relates to a process for the production of polyurethane/urea moldings from a reaction injection molding process by processing the reaction mixture consisting of a diisocyanate and an isocyanate-reactive component via the one-shot process at an isocyanate index of about 80 to 130. The diisocyanate is an unmodified cycloaliphatic diisocyanate. The isocyanate-reactive component consists of 1) at least one polyol having functional groups which are hydroxyl groups, amine groups, or mixtures of hydroxyl groups and amine groups such that the equivalent ratio of hydroxyl groups to amine groups is from 0:1 to 1:1, and 2) at least one chain extender which is selected from diols, triols, primary aliphatic amines, secondary aliphatic amines, aminoalcohols and mixtures thereof. The equivalent ratio of hydroxyl groups to amine groups in the chain extender component is from 1:2 to 10:1.

Abstract: The present invention relates to a process for the production of molded articles via the reaction injection molding technique. According to the RIM process, a reaction mixture is introduced into a closed mold, allowed to react fully, and removed from the mold. More specifically, these reaction mixtures comprise an isocyanate-reactive material, a chain extender, and a stable, liquid diallophanate modified diphenylmethane diisocyanate (MDI). Two specific processes for the preparation of the suitable diallophanate modified diisocyanate are disclosed. These diallophanate modified isocyanates either have an isocyanate group content from about 12 to 30%, or from about 5 to 29%.

Abstract: This invention relates to a process for the production of polyurethane/urea moldings which exhibit both high flexural modulus and high impact strength. The process comprises reaction injection molding of a reaction mixture in the presence of a catalyst via the one-shot process. The isocyanate component of this invention is a prepolymer of methylenebis(cyclohexyl isocyanate) having an NCO content of 12-27%, an average isocyanate functionality of less than 2.3, a monomer content of greater than about 25% by weight, and containing urethane or urea groups. The isocyanate-reactive blend comprises a high molecular weight polyether polyol and a low molecular weight chain extender, wherein the isocyanate-reactive blend has an OH:NH equivalent ratio of from 1:1 to 15:1. This invention also relates to the polyurethane/urea molded article produced by the above process.

Abstract: Allophanate-modified MDI which is a storage stable liquid at 25.degree. C. is produced by reacting a monoisocyanate and an organic material having at least two hydroxyl groups and a molecular weight of from about 60 to about 6,000 to form a urethane. The urethane is then reacted with and isomeric mixture of MDI in an amount such that the product isocyanate will have an NCO content of from about 12 to about 30%. The isomeric mixture of MDI is composed of 4,4'-diphenylmethane diisocyanate containing from 0 to about 60% by weight 2,4'-MDI and less than 6% by weight of the 2,2'-MDI. This allophanate-modified MDI is further reacted with an organic isocyanate-reactive material to produce an allophanate-modified MDI prepolymer containing urethane, urea and/or biuret groups having an NCO content which is generally from about 5 to about 29% by weight. The prepolymers of this invention are particularly useful in reaction injection molding processes because they give molded articles having improved flex modulus.

Abstract: Allophanate-modified MDI which is a storage stable liquid at 25.degree. C. is produced in two steps. First, a monoisocyanate is reacted with an organic material having about 1.8 or more hydroxyl groups and a molecular weight of from about 60 to about 6,000 to form the urethane. The urethane is then reacted with an isomeric mixture of MDI in an amount such that the resultant isocyanate will have an NCO content of from about 3 to about 28%. The isomeric mixture of diphenylmethane diisocyanate contains from about 0 to about 60% by weight 2,4'-diphenylmethane diisocyanate, less than 6% by weight 2,2'-MDI and the remainder 4,4'-MDI. The prepolymers of this invention are particularly useful in reaction injection molding processes because molded articles having improved flex modulus are obtained.

Abstract: The present invention is directed to polyurethane moldings produced via the RIM process. These polyurethane moldings have excellent reactivity, demold properties (at a 30 s demold), and good elongation and tear strength, and comprise the reaction product of an aliphatic polyisocyanate having a viscosity of less than about 20,000 mPa.multidot.s at 25.degree. C. and a NCO functionality of 2.3 to 4.0 with an isocyanatereactive component comprising b1) a relatively high molecular weight organic compound containing at least one of the groups selected from the group consisting of hydroxy groups and amine groups; and b2) a low molecular weight chain extender selected from the group consisting of diols, triols, primary amines, secondary amines, aminoalcohols, and mixtures thereof; in the presence of a catalyst. The OH:NH ratio of the chain extender is from 1:1 to 25:1.

Abstract: The present invention is directed to polyurethane moldings produced via the RIM process. These polyurethane moldings have excellent reactivity, demold properties (at a 30s demold), and good elongation and tear strength, and comprise the reaction product of an HDI prepolymer having an NCO content of 5 to 25%, a functionality of less than 2.3, and a monomer content of less than 10%, with an isocyanate-reactive component comprising b1) at least one relatively high molecular weight organic compound containing at least about two isocyanate-reactive hydroxyl groups; b2) at least one relatively low molecular weight organic compound selected from the group consisting of diols, aminoalcohols, and mixtures thereof; and b3) at least one relatively low molecular weight hydroxyl-based crosslinking compound containing no more than one aliphatic amine hydrogen atoms capable of reacting with isocyanate groups; in the presence of at least one catalyst.

Abstract: This invention relates to a process for the production of a polyurethane molded part from a reaction injection molding process. The reaction mixture comprises:A) an isocyanate distillation residue resulting from the production of 1,6-hexamethylenediisocyanate by phosgenation of the corresponding amine, followed by the distillation of the pure 1,6-hexamethylenediisocyanate to yield said residue, wherein said residue has an NCO content of from 20 to 27%, a viscosity of from 1500 to 5000 cps at 25.degree. C., and from 0.1 to 3% by weight of hydrolyzable chlorides; withB) an isocyanate-reactive component comprising at least one organic compound having a molecular weight of from 500 to 10,000 and containing at least two isocyanate-reactive hydroxyl groups, and at least one organic diol having a molecular weight of from about 62 to 500,in the presence ofC) a specific catalyst mixture.

Abstract: Novel liquid, room temperature polyisocyanate having isocyanate group contents of from 6 to 31% by weight, are prepared by reacting:a) a methylene-bis(phenyl isocyanate) containing1) from 65 to 90% by weight of the 4,4'-isomer,2) from 10 to 35% by weigh of the 2,4'-isomer, and3) no more than 2% by weight of the 2,2'-isomer, with the percents of components a)1), a)2), and a)3) totalling 100%, andb) a mixture of:1) one or more organic compounds having molecular weights of from 400 to 6000 and containing from 2 to 8 isocyanate reactive groups, and2) one or more organic diols having molecular weights of from 60 to 200, excluding tripropylene glycol, the weight ratio of component b)1) to b)2) being from 150:1 to 5:1.When used in a RIM process, molded products are obtained which have improved tear strength, improved flexural modulus, improved impact resistance, and improved tensile strength.

Abstract: Products made using the RIM process where the reaction mixture contains an acidic release agent have improved green strength when the reaction mixture also contains a peralkylated polyalkylene polyamine.

Abstract: This invention relates to a process for preparing polyurethanes by reacting, in accordance with the resin transfer molding technique at an isocyanate index of about 80 to about 120,(a) an organic polyisocyanate;(b) about 60 to about 98 percent by weight, based on the total amount of components (b) and (c), of at least one isocyanate-reactive compound containing at least two isocyanate-reactive hydrogen atoms and having a molecular weight of from about 400 to about 10,000;(c) about 2 to about 40 percent by weight, based on the total amount of components (b) and (c), of (i) 2-methyl-1,3-propanediol or (ii) a mixture of 2-methyl-1,3-propanediol with (1) up to about 30% by weight, based on the total amount of component (c), of a chain extender other than 2-methyl-1,3-propanediol and/or (2) up to about 5% by weight, based on the total amount of component (c), of a crosslinking agent; and(d) one or more catalysts and, optionally, one or more other auxiliaries and/or additives.

Abstract: Disclosed herein is an improved polyurea system comprising a reaction product of a polyisocyanate and a polyamine and an amine chain extender, the improvement comprising the polyisocyanate containing diethyl methylene diisocyanate, a prepolymer thereof or a mixture thereof, in an amount sufficient to slow down the reaction for use in a reaction injection molding.