PROCESS FOR THE PREPARATION OF FLAME-RESISTANT AND COLD-RESISTANT POLYURETHANE FOAMS AND THEIR USE AS INNER COATINGS OF STORAGE-TANKS

摘要

1. Process for the production of flameproof, cold-resistant polyurethane foams by reacting polyisocyanates with relatively high molecular weight compounds containing at least two hydroxyl groups and having an OH number of 150-300 in the presence of chain-lengthening and crosslinking agents containing at least two active hydrogen atoms, blowing agents, activators and phosphorus containing compounds, optionally in the presence of auxiliaries and additives known per se, characterised in that 1. a modified diphenylmethane diiscyanate is used as the polyisocyanate, 2. a polyester is used as the relativly high molecular weight compound containing at least two hydroxyl groups and 3. a) a C2 -C6 -alkanediol and optionally b) an adduct of an alkylene oxide and an amino compound containing at least three hydroxyl groups and having an OH number of 400-800 are used as the chain-lengthening and crosslinking agents.