| 摘要 |
1485596 Polyester compositions RHONEPOULENC INDUSTRIES 22 Dec 1975 [24 Dec 1974] 52421/75 Heading C3R A composition comprises an OH-terminated polyester (P), containing no non-aromatic C-to- C unsaturation, of softening temp. 70-130‹ C., OH-number 150-250, and acid-number <10, and a cross-linking agent (C) comprising a dianhydride with ester groups being the product of a reaction between trimellitic anhydride and a diol, with softening temp. 60-130‹ C. (P) may be derived from diol(s) and optionally triol(s) and aromatic dicarboxylic acid(s) or alkyl esters thereof, and optionally saturated aliphatic acid(s) and/or aromatic or aliphatic acid(s) having >2 COOH groups: e.g. (P) may be the reaction product of a triol with high MW poly(ethylene terephthalate). (C) may be formed by reacting, at 180-250‹ C., trimellitic anhydride and a diol in a mole ratio of from 2 to 1À5; the diol may be a C 2-10 aliphatic diol. The composition may be cross-linked at 140-200‹ C. The composition may be used in a binder for a powder paint, 0À1-1% wt. of spreading agents, e.g. acrylic polymers or silicones, being added. Other conventional paint additives may also be added. The mixtures may be applied by fluidized bath or electrostatic spraying, e.g. on glass articles. |
