| 摘要 |
<p>1,207,794. Modified epoxy resins. SHELL INTERNATIONALE RESEARCH MAATSCHAPPIJ N.V. 13 Jan., 1969, No. 1831/69. Heading C3B. [Also in Division C7] Resins containing free carboxyl groups which are thinnable by water after neutralization are prepared by a three-stage process: (i) a polyglycidyl ether of a polyhydric phenol is reacted, at 0À8-1À3 acid equivalents per epoxy equivalent, with monocarboxylic acids, at least 50% of which are ethylenically unsaturated fatty acids, e.g. drying oil acids; (ii) the resultant polyester is reacted with at least 4% by weight of an ethylenically unsaturated polycarboxylic acid or anhydride, e.g. maleic anhydride; and (iii) the resultant polycarboxylated polyester is reacted at > 150‹ C. with an oil-soluble non- heat-reactive phenolic resin. Step (i) may be carried out in the presence of an esterification catalyst, e.g. triphenylphosphine. Step (ii) may be carried out at > 175‹ C., e.g. 180-220‹ C. The alde. phenolic resin may be a condensate of a para-substituted phenol and formaldehyde, e.g. p-tert-butyl phenol. In order to render the resin water dispersible at least 40% of the carboxyl groups are neutralized, e.g. with a primary, secondary or tertiary aliphatic or cycloaliphatic amine. A lyotropically active solvent, e.g. ethylene glycol monobutyl ether may also be present in coating compositions. Conventional pigments may be present. The compositions are useful in electrodeposition processes.</p> |
