Abstract: There is provided a method of producing an open cell rigid polyurethane foam which comprises reacting a specified polyol mixture by use of water as the substantially sole blowing agent without the use of a volatile hlorofluorocarbon as a blowing agent. There is provided a further method of producing an open cell rigid polyurethane foam particularly suitable for use as a shock absorbing material which comprises reacting a specified polyol/monool mixture. Water is used in an amount of 0.5-5.5 parts by weight in relation to 100 parts by weight of the polyol mixture or polyol/monool mixture used.

Abstract: A polyether polyol produced by using an N-amino-ethylpiperazine-ethylene oxide aduct as an initiator and addition-polymerizing an alkylene oxide thereto and having a molecular weight of about 2000 to 7000; a process for producing a flexible urethane foam starting with the above polyether polyol; a process suited for the production of a hot-cure urethane foam which comprises using the above polyether polyol with a hydroxyl value of 40 to 80 mg KOH/g and, as a blowing agent, 4.6 to 6.0 weight parts of water based on 100 weight parts of the polyol; and a process suited for the production of a cold-cure urethane foam which comprises using the above polyether polyol with a hydroxyl value of 23 to 50 mg KOH/g and, as a blowing agent, 2.5 to 5.0 weight parts of water on the same basis.

Abstract: A polyether polyol produced by using an N-aminoethylpiperazine-ethylene oxide aduct as an initiator and addition-polymerizing an alkylene oxide thereto and having a molecular weight of about 2000 to 7000; a process for producing a flexible urethane foam starting with the above polyether polyol; a process suited for the production of a hot-cure urethane foam which comprises using the above polyether polyol with a hydroxyl value of 40 to 80 mg KOH/g and, as a blowing agent, 4.6 to 6.0 weight parts of water based on 100 weight parts of the polyol; and a process suited for the production of a cold-cure urethane foam which comprises using the above polyether polyol with a hydroxyl value of 23 to 50 mg KOH/g and, as a blowing agent, 2.5 to 5.0 weight parts of water on the same basis.

Abstract: A method of producing an open cell rigid polyurethane foam which comprises reacting a mixture of polyols having a hydroxyl value of 160-360 mg KOH/g with a polyisocyanate in the presence of water as a blowing agent in an amount of 6-12 parts by weight in relation to 100 parts by weight of the mixture of polyols at an isocyanate index of 70-120, the mixture of polyols comprising:(a) 30-60% by weight of a first polyoxyalkylene polyol having a functionality of 2-3.

Abstract: The present invention relates to a polyether polyol which is prepared by(i) reacting 3.0 to 4.0 molecular equivalents of ethylene oxide with one molecular equivalent of 2,3- or 3,4-tolylenediamine, or a mixture thereof in the absense of catalyst, and thereafter,(ii) reacting 2.8 to 4.8 molecular equivalents of propylene oxide with one molecular equivalent of the reaction product in the presence of an alkali metal hydroxide in an amount of not more than 0.8% by weight based on the 2,3- or 3,4-tolylenediamine, or the mixture thereof.The present invention also relates to a rigid polyurethane foam which is prepared by reacting a polyol mixture containing not less than 50 wt % of the above-mentioned polyether polyol with an isocyanate. The rigid polyurethane foam is obtained with reduced fron requirements.

Abstract: A method of producing a rigid urethane foam, which comprises reacting a blend polyol consisting of a polyol having a hydroxyl value of 300 to 450 mg KOH/g as prepared by using an acyclic sugar alcohol of 5 to 6 carbon atoms as an initiator and one or more other polyols, said blend polyol having a sugar alcohol content of 3 to 14 weight % and an average hydroxyl value of 300 to 430 mg KOH/g, with a polyisocyanate using 4.0 to 7.0 weight parts of water based on 100 weight parts of said polyol composition as a blowing agent, can reduce the CFC requirements by 50 to 100 percent as compared with the known production technology for rigid urethane foams and, moreover, the adhesive property of the resulting foam is not inferior to that of the conventional urethane foam.

Abstract: A polyol composition comprising(a) a polyether polyol with an average molecular weight of 2,000 to 10,000,(b) an adduct of a carboxylic acid having not less than 8 carbon atoms with ethylene oxide or both ethylene oxide and propylene oxide and(c) a diol with an average molecular weight of 62 to 400, having one or more primary hydroxyl groups;in a ratio of (88 to 98):(2 to 8):(0 to 4) by weight is suitable for the production of flame-retardant flexible polyurethane foam and a flame-retardant flexible polyurethane foam produced by reacting(i) the above polyol composition with(ii) a polyisocyanatein the presence of(iii) water,(iv) both a foam-setting agent for slab foam and a foam-setting agent for HR foam(v) both a metal-containing catalyst and a tertiary amine catalyst and(vi) a flame retardant comprising a triarylphosphatenot only has an excellent flame retardant effect but also causes no discoloration of the foam-covering material.

Abstract: Polyetherpolyols useful in preparing rigid polyurethane foam excellent in dimensional stability and inflammability. These polyetherpolyols are obtained by reacting alkylene oxide with compounds containing active hydrogen atoms, part or all of which comprise the reaction product obtained by heating the distillation residue secured as a byproduct in the distillation process of a crude polyisocyanate in the presence of (1) water, alcohols and/or amines and (2) hydroxides or oxides of alkali metals or alkaline earth metals and/or monoalkanolamines.