Explanation

The first kind is polyester resin with different branch chain structure and molecular weight, which is produced through polycondensation reaction reaction with polyol and polyacid (anhydride) as main raw materials, and is mainly used in coatings industry. The representative variety is phthalic acid type alkyd resin, which is obtained by co condensation of phthalic anhydride and polyols (such as glycerol, pentaerythritol, etc.). It is brittle, D93 has poor solubility, and is easy to gel. In industry, it is often used to introduce the co condensation modification of human, meta resin acid (rosin acid), unsaturated fatty acid (tung oil, castor oil acid) and saturated fatty acid to form a branched chain structure in alkyd resin, reduce the crosslinking density, improve its solubility, compatibility and heat resistance with each component in varnish, and increase the flexibility and elasticity of products. alkyd resin based coating and paint film have long service life, good glossiness, good water resistance, flexibility resistance, heat resistance, impact resistance and dimensional stability, tensile strength of 20.6~32.4MPa. impact strength CWlSWm, coefficient of volume resistance lX1012n. cm, shrinkage of 0.4%~0.7% alkyd resin is the most widely used coatings resin. It is mainly used in the field of coatings, and can also be used as adhesive, toughener, ink, etc

Classification