Hardening agent for polyurethane polybutadiene terminated by a base of the hydroxyl groups, the curable composition containing this agent and of the grains of propellant linked by the polyurethane

摘要

P the invention described in the hardening agents of a polyurethane and their applications. / p & & p & it has been found that of the salicylic acid esters are suitable for blocking of a polyisocyanate, which makes it possible to prepare the grains of propellant linked by the polyurethane of polybutadiene with hydroxyl groups and having a duration prolonged possible in pots of storage at ambient temperatures. / p & & p & the unblocking (dissociation) occurs easily at normal temperatures of hardening of the propellant, which allows normal speeds of hardening. / p