| 摘要 |
<p>Powdered thermosetting compositions including a binder consisting of a mixture of polyesters containing carboxyl groups, and a cross-linking agent with functional groups capable of reacting with the carboxyl groups, are disclosed. The polyesters include (a) a semi-crystalline polyester containing carboxyl groups and consisting of 85-100 mol % of 1,4-cyclohexanediol and 0-15 mol % of at least one other aliphatic and/or cycloaliphatic polyol, based on the total of alcohols, and 85-100 mol % of a straight-chain saturated dicarboxylic aliphatic acid having 4-14 carbon atoms, and 0-15 mol % of at least one other aliphatic and/or cycloaliphatic and/or aromatic polycarboxylic acid, based on the total of acids; and (b) an amorphous polyester containing carboxyl groups and consisting of 70-100 mol % of isophthalic acid and 0-30 mol % of at least one other aliphatic and/or cycloaliphatic and/or aromatic polycarboxylic acid, based on the total of acids, and 70-100 mol % of neopentylglycol and/or 2-butyl-2-ethyl-1,3-propanediol, and 0-30 mol % of at least one other aliphatic and/or cycloaliphatic polyol, based on the total of alcohols. Said powdered thermosetting compositions are particularly useful for preparing powdered varnishes and paints, and provide coatings having remarkable weather resistance, high gloss and excellent mechanical properties.</p> |
