| 摘要 |
<p>Polyurethanes contg. both urethane and semicarbazide groups, ar made by reacting an isocyanate-modified polyhydroxy cpd. with a mol. wt. of 500 - 5000, with terminal NCO groups, with 10 - 90% (on NCO content) of a chain-lengthening polyhydric alcohol, and subsequently with 90 - 110% (on remaining NCO content) of a hydroxyalkane carboxylic acid hydrazide. Solns. of the product are useful as coating agents and impregnants.</p> |
