摘要:
The present invention is directed to a rigid, molded foam produced by reacting: a) one or more organic polyisocyanates, with b) a polyol blend comprising i) 100 parts by weight of a mixture comprising: 1) from 30 to 80 parts by weight of one or more polyethers having hydroxy functionalities of 2 or 3 and molecular weights of from about 1,000 to about 8,000, the polyethers further being characterized as containing no nitrogen atoms and not being filled polyethers, 2) from 10 to 50 parts by weight of one or more adducts of toluene diamine and an alkylene oxide, the adduct having a molecular weight of from about 350 to about 700, 3) from 0 to 15 parts by weight of one or more di- or trialkanol amines, with the amounts of components 1), 2) and 3) totaling 100 parts, and c) from about 0.1 to about 4 parts by weight per 100 parts by weight of component b) of a silicone cell-opening surfactant and d) from 1 to 7 parts by weight of water, and e) from 0.1 to 2 parts by weight of at least one tertiary amine catalyst; wherein the reaction mixture contains no auxiliary blowing agents and wherein the amount of polyisocyanate is such that the isocyanate index is from 95 to 120.
摘要:
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.
摘要:
A method for making an energy-absorbing foam having a density that is less than about 7 pcf that exhibits excellent strength properties and that is particularly suitable for automobile bumper applications. The invention is also directed to the energy-absorbing foam made with the method.
摘要:
This invention relates to a process for preparing optionally reinforced rigid polyurethanes by the reaction, under resin transfer molding conditions at an isocyanate index of 90 to 130, of(a) an organic polyisocyanate, with(b) 15 to 80 percent by weight, based on the total of components (b), (c), and (d), of certain polyester polyols having long-chain fatty acid or fatty alcohol groups, a number average molecular weight of 500 to 3000, and a metal ion content below 100 ppm; and(c) 20 to 85 percent by weight, based on the total of components (b), (c), (d) and (e), of one or more crosslinkers, other than component (b), containing 3 to 8 hydroxyl groups and having a molecular weight of 92 to 1000 and a metal ion content below 100 ppm,(d) 0 to 60 percent by weight, based on the total of components (b), (c), and (d), of an isocyanate-reactive compound, other than a polyester polyol of component (b), having a metal ion content below 100 ppm, selected from (i) an isocyanate-reactive polyol containing 3 to 6 hydroxyl groups and having a number average molecular weight of more than 1000 to 10,000, (ii) an isocyanate-reactive diol having a number average molecular weight of 62 to 10,000, and (iii) mixtures thereof, and(e) 0.05 to 3 parts by weight, based on the total amount of components (b), (c), (d) and (e), of a delayed action catalyst.
摘要:
The present invention is directed to an isocyanate reactive mixture comprising from about 17 to about 85% by weight of one or more non-filled polyether polyols having a hydroxyl functionality of from 1.5 to 3 and molecular weights of from 1,500 to 8,000; from about 12 to about 80% by weight of one or more non-tertiary amine containing polyether polyols having a hydroxyl functionality of from 3 to 8 and a molecular weight of from 150 to 1,000; from about 0 to about 4% by weight of one or more primary or secondary diamines or amino alcohols and from 3 to about 12% by weight of water. The invention is also directed to a water-blown, energy absorbing foams made from the isocyanate reactive mixture.
摘要:
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.
摘要:
A method for making an energy-absorbing foam with polyurethane fillers that produces an energy-absorbing foam with properties that are comparable to a foam made without fillers.
摘要:
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.
摘要:
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. A catalyst capable of catalyzing the reaction between isocyanate groups and isocyanate-reactive groups is also present in the reaction mixture.
摘要:
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.