EPOXY-POLYESTER RESIN COMPOSITION WITH EXCELLENT WEATHER RESISTANCE AND MECHANICAL PROPERTIES AND POWDERED PAINT COMPOSITION

摘要

PURPOSE: An epoxy modified polyester resin for a powdered paint, its preparation method and a powdered paint composition containing the resin are provided, to improve weather resistance, pollution resistance and mechanical properties. CONSTITUTION: The method comprises the steps of preparing a core-shell material-dispersed epoxy resin comprising 5-20 wt% of a core-shell material having a particle size distribution of 300-20,000 Angstrom and 80-95 wt% of an epoxy resin having an epoxy equivalence of 100-300 g/eq; preparing a carboxyl polyester resin having an organic/glycol equivalence ratio of 1.05-1.2, an acid value of 30-80 mg KOH/g and a melt viscosity of 10-50 poise (200 deg.C); and reacting the carboxyl polyester resin and the core-shell material-dispersed epoxy resin in the ratio of 1 : 0.1-0.2 by weight. Preferably the epoxy resin is a monovalent or divalent alicyclic epoxy resin or aliphatic epoxy resin.