| 摘要 |
Polyurethane powder coating compns. with good anti-weathering, anti-chemicals, anti-abrasive and low baking temp. were prepd. by the reaction of partially blocked isocyanate compd. (A ; mp 50-150≦̸C) contg. free NCO and blocked NCO group by blocking agent (mp>=180≦̸C) with high mol. wt. compd.(B) contg. active H. At least the sum of each group in reactants was larger than 5, an B compd. was fed to the mixts. more than A.
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