| 摘要 |
PROBLEM TO BE SOLVED: To improve the heat resistance and mechanical characteristics of a polycarbodiimide compd. by reacting it with a hydroxyl or mercapto compd. in the presence of an alkali or alkaline earth metal alcoholate. SOLUTION: A polycarbodiimide compd. is obtd. by decarboxylating an org. diisocyanate having a mol.wt. of 5,000 or higher by heating it in a hydrocarbon solvent. A cross-linked polycarbodiimide having iso(thio)urea bonds is obtd. by reacting the polycarbodiimide compd. with a compd. having at least two hydroxyl or mercapto groups in an amt. of 50mol% or lower (based on the carbodiimide bonds in the polycarbodiimide compd.; the same applies hereunder) in the presence of an alkali or alkaline earth metal (1-30C)-alcoholate in an amt. of 0.1-20mol%. The cross-linked polycarbodiimide is heated to 50-300 deg.C to further cross-link it, and the resultant thermally cross-linked product is further heated to 500-3,000 deg.C to be converted into an inorg. material. |
