Abstract:
The invention relates to a method for producing viscoelastic foam materials, by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive with isocyanate groups, in the presence of c) catalysts and d) expanding agents. The invention is characterised in that a) polyisocyanates are used as ai) diphenylmethane diisocyanate or aii) mixtures of diphenylmethane diisocyanate and polymethylene polyphenylene polyisocyanates, and/or aiii) prepolymers containing isocyanate groups, which can be produced by reacting aiv) polyether alcohols with diphenylmethane diisocyanate or mixtures of diphenylmethane diisocyanate and polymethylene polyphenylene polyisocyanates, and mixtures of at least one catalyst ci) and at least one catalyst cii) are used as catalysts.
Abstract:
The invention relates to a process for producing viscoelastic polyurethane foams by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups in the presence of c) catalysts, d) blowing agents, wherein ai) diphenylmethane diisocyanate or aii) mixtures of diphenylmethane diisocyanate and polymethylenepolyphenylene polyisocyanates and/or aiii) prepolymers which comprise isocyanate groups and can be prepared by reacting aiv) polyether alcohols with diphenylmethane diisocyanate or mixtures of diphenylmethane diisocyanate and polymethylenepolyphenylene polyisocyanates are used as a) polyisocyanates and mixtures of at least one catalyst ci) and at least one catalyst cii) are used as catalysts.
Abstract:
The invention relates to a process for producing viscoelastic polyurethane foams by reacting a) polyisocyanates with b) compounds having at least two hydrogen atoms which are reactive toward isocyanate groups in the presence of c) catalysts, d) blowing agents, wherein ai) diphenylmethane diisocyanate or aii) mixtures of diphenylmethane diisocyanate and polymethylenepolyphenylene polyisocyanates and/or aiii) prepolymers which comprise isocyanate groups and can be prepared by reacting aiv) polyether alcohols with diphenylmethane diisocyanate or mixtures of diphenylmethane diisocyanate and polymethylenepolyphenylene polyisocyanates are used as a) polyisocyanates and mixtures of at least one catalyst ci) and at least one catalyst cii) are used as catalysts.