PURPOSE: To produce the titled polyurethane, by reacting a specified polyester- diol with an organic diisocyanate at a predetermined ratio and chain-extending the prepolymer.
CONSTITUTION: A hydroxyl group-terminated polyesterdiol (of an MW of 800W 1,500) is obtained by reacting 3-methyl-1,5-pentanediol with a dicarboxylic acid (e.g., adipic, succinic or sebacic acid). Said polyesterdiol is reacted with an organic diisocyanate (e.g., 4,4'-diphenylmethane diisocyanate) in an amount satisfying the relationship (wherein M is the average MW of the polyester-diol and R is a molar ratio of the organic diisocyanate to the polyester-diol) at a temperature ≤about 120°C, and the obtained isocyanate-terminated prepolymer is reacted with a chain extender (e.g., 1,4-butanediol) at about 50W160°C.
ISHIGURO MICHIHIRO
OKAMURA TAKAYUKI
Next Patent: BAG FILTER