High temperature resistant polyester resin with low usage amount of TGIC (triglycidyl isocyanurate) for powder coating and preparation method of high temperature resistant polyester resin

The invention provides high temperature resistant polyester resin with low usage amount of TGIC (triglycidyl isocyanurate) for powder coating and a preparation method of the high temperature resistant polyester resin, and the high temperature resistant polyester resin is prepared from the following raw materials in parts by weight: 20 to 40 parts of neopentyl glycol, 0 to 30 parts of TMP (trimethylolpropane), 30 to 60 parts of terephthalic acid, 10 to 40 parts of IPA (isophthalic acid), and 1 to 20 parts of adipic acid. According to the high temperature resistant polyester resin provided by the invention, polyester resin has a high molecular weight and a high net structure by using the TMP and controlling the usage amount of the TMP; the acid value range of a finished product is controlled between 28 to 32 by controlling the ratio of alcohol to acid, so that the usage amount of the TGIC is lowered when the polyester resin and a curing agent are cured and crosslinked. Meanwhile the obtained polyester resin has high temperature resistance and yellowing resistance.