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Polyurethanes and polyurethane rigid foams prodn - using as polyol component a phenol-aldehyde condensation product prepd. in presence of alkoxylated tert. alkanolamines
Polyurethanes and polyurethane rigid foams prodn - using as polyol component a phenol-aldehyde condensation product prepd. in presence of alkoxylated tert. alkanolamines
Polyurethanes and rigid polyurethane foams with a wide variety of uses are prepd. by reacting (I) a condensation prod. prepd. by reacting (a) a phenol and (b) an aldehyde, in the presence of (c) an alkoxylated tert. alkanolamine at 40-90 degrees C and alkoxylating the prod. at 50-120 degrees C and (II) a polyisocyanate, opt. in the presence of a blowing agent, a foam stabiliser and similar auxiliaries. Components (I) have a low viscosity at satisfactory hydroxyl numbers, and have a good solubility for blowing agents. Their viscosity can be controlled over a wide range. Can be used without purification.
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