摘要:
This invention relates to solid reaction products of aliphatic, cycloaliphatic or araliphatic mono- and/or polyisocyanates and organic, weakly acid mono- and/or polycarboxylic acids for the production of cellular plastics articles and particularly polyurethane foams. The products of the present invention may also be in the form of mixtures with carboxylic acids. The products are suitable for the production of cellular or porous plastics articles, but are preferably used in the preparation of cellular thermoplastic polyurethanes and semi-rigid and particularly rigid polyurethane integral skin foams having a compact outer skin formed by foaming the reaction mixture in closed molds.
摘要:
The present invention is directed to a reactive polyurethane mixture comprising:A) at least one polyisocyanate,B) a polyol mixture comprising:B1) at least one polyol containing three or more hydroxyl groups and having a molecular weight in the range from 800 to 6,000,B2) at least one polyol containing three or more hydroxyl groups and having a molecular weight in the range from 400 to 799 andB3) at least one polyol containing three or more hydroxyl groups and having a molecular weight in the range from 92 to 399, andC) at least one polyamine.
摘要:
The invention relates to a process for improving the flowability and preventing the agglomeration of finely divided dimerized 2,4-toluene diisocyanate in which a precipitated silicas and/or pyrogenic silica having a hydrophobic surface is added to the finely divided dimerized 2,4-toluene diisocyanate. The invention also relates to the finely divided dimerized 2,4-toluene diisocyanate prepared by this process.
摘要:
The present invention relates to N,N'-bis-(4-isocyanatocyclohexyl)urea obtained from the reaction with water of cyclohexane-1,4-diisocyanate having a high trans isomer content. This invention further relates to the process for preparing the N,N'-bis(4-isocyanatocyclohexyl)urea and to its use in the synthesis of polyurethanes.
摘要:
Low molecular weight 4,4'-diphenylmethane-uretdione-diisocyanates corresponding to the formula: ##STR1## wherein n is a number from 0 to 1,are made by dimerizing diphenylmethane-4,4'-diisocyanate at a temperature of 50.degree. C. or less in a mixture of non-polar and moderately polar solvents in the presence of a dimerization catalyst. The dimerization product may then be worked up at low temperatures (i.e., .ltoreq.50.degree. C.). The dimerization products of diphenylmethane-diisocyanate thus obtained generally have only a small amount of oligomeric uretdione-diisocyanates present. These dimerization products may be used advantageously in the synthesis of polyurethanes.
摘要:
Diisocyanates corresponding to the formula ##STR1## in which R.sup.1, R.sup.2, R.sup.3, R.sup.4, R.sup.5 and R.sup.6 (an isocyanate-containing radical) are as defined herein are made by several processes. These diisocyanates may be made by phosgenating the diamine in which the diisocyanate is based. They may also be produced by treating the bis-urethane of the tertiary alcohol corresponding to the diisocyanate with phosgene. Such diisocyanates may also be made by treating a specific type of bis-urea with hydrogen chloride. The diisocyanates corresponding to the above-given formula are particularly useful in the production of polyurethanes having good flame-proof and mechanical properties.
摘要:
This invention relates to a process for the production of polyurethanes, particularly polyurethane foam moldings having a compact skin and a cellular core, using special tin activators.
摘要:
The present invention relates to a heat curable, one-component polyurethane reactive compositions containingA) surface-modified, finely divided polyisocyanates in which 0.1 to 25 equivalent percent, based on the total number of NCO groups, of the NCO groups are deactivated andB) a mixture of relatively high molecular weight compounds having isocyanate-reactive groups containing1) 5 to 40 wt. %, based on the weight of component B), of one or more aliphatic polyether polyamines and2) 60 to 95 wt. %, based on the weight of component B), of a polyol mixture containingi) 10 to 60 wt. %, based on the weight of component B2), of at least one polyester polyol andii) 40 to 90 wt. %, based on the weight of component B2), of at least one polyether polyol with predominantly primary hydroxyl groups.The present invention also relates to use of the heat curable, one-component polyurethane reactive compositions to prepare coatings, adhesives, anti-drumming products and sealants, especially seam sealants.
摘要:
The present invention relates to a process for the preparation of a modified 1,5-naphthylene diisocyanate containing urea and biuret groups comprising reacting(a) 1,5-naphthylene diisocyanate in molten form with(b) a mixture comprising about 0.02 to about 0.5 mole of water per mole of 1,5-naphthylene diisocyanate and about 1 to about 10 parts for each part of water of an organic solvent.The present invention further relates to a process for the preparation of elastomeric moldings comprising reacting by the one-shot or prepolymer process at an isocyanate index of 70 to 130 a modified 1,5-naphthylene diisocyanate containing urea and biuret groups with compounds containing at least two isocyanate-reactive groups and having a molecular weight in the range from about 500 to about 10,000 and, optionally, organic compounds containing isocyanate-reactive groups and having a molecular weight in the range from 60 to 499.
摘要:
The present invention relates to heat-curable reaction systems prepared by mixing (a) solid polyisocyanates (optionally deactivated) having melting points above 80.degree. C., (b) OH- and/or NH.sub.2 -terminated polyoxyalkylene polyethers that have molecular weights of 400 to 10,000 and are liquid at room temperature, (c) solid OH- and/or NH.sub.2 -terminated polyesters that have molecular weights of 400 to 20,000 and are solid at room temperature, and which are thoroughly distributed throughout the mixture but are not homogeneously miscible with the polyether, (d) optional low molecular weight chain-extending agents that contain OH and/or NH.sub.2 groups and have a molecular weight of 62 to 399, and (e) optional catalysts and other auxiliaries. The invention further relates to a method for preparing elastomers, coating compounds, sealing compounds, or adhesives by heat-curing the heat-curable systems.