FIELD: chemistry.
SUBSTANCE: present invention pertains to the method of obtaining hard polyurethane or polyisocyanurate foams which can be used for making refrigerating machines. The method involves reaction of: (a) organic diisocyanate and/or polyisocyanate with (b) activated aromatic amine polyol, with ratio of equivalents of groups (a) to groups with active hydrogen (b) ranging from 0.9 to 3.0, in the presence of, (c) more carbon dioxide and water, and (d) C3-C5 fluorocarbon. The invention aims at designing a method of producing hard urethane foams, with good physical properties, including a low k-factor, using environmentally acceptable foaming agents. This given task is solved by that, HFC (hydrofluorocarbon) is used as the foaming agent, combined with water and supplementary carbon dioxide.
EFFECT: reduced minimum filling density and filling percentage, required for frost resistant foam plastics at -30°C, as well as the k-factor of the obtained foam plastic.
12 cl, 1 tbl, 6 ex
