| 摘要 |
Thermosetting compositions comprise by weight, (I) 100 parts of the reaction product of (a) 25-56 equiv. per cent of isophthalic acid, terephthalic acid, a lower dialkyl ester of isophthalic acid, a lower dialkyl ester of terephthalic acid or a mixture of two or more thereof, (b) 15-46 equiv. per cent of a diol, and (c) 13-44 equiv. per cent of a saturated aliphatic polyhydric alcohol having at least 3 hydroxyl groups, and (II) 2-20 parts of pyromellitic acid and/or pyromellitic dianhydride. The compositions which are preferably pulverulent may also contain fillers and/or pigments and/or thixotropic agents. They are useful as coating compositions.ALSO:Metal surfaces may be coated by, e.g. a film-spreader or fluidized bed, with compositions comprising by weight, (I) 100 parts of the reaction product of (a) 25-56 equiv. per cent of isophthalic acid, terephthalic acid, a lower dialkylester of isophthalic acid, a lower dialkyl ester of terephthalic acid or a mixture of two or more thereof, (b) 15-16 equiv. per cent of a diol and (c) 13-44 equiv. per cent of a saturated aliphatic polyhydric alcohol having at least 3. OH groups, and (II) 2-20 parts of pyromellitic acid and/or its dianhydride. The compositions which are preferably pulverulent may also contain fillers and/or pigments and/or thixotropic agents. |
