在粉末涂料配方中,增塑剂是充塞于相邻高分子化合物链段之间增大其间距,减羽其相互之向的作用力,从而降低舱裂和断折的趋势的助剂。对于含有极基团的增塑剂,可以与高聚物的极性基团发生作用,使高聚物分子缝段之间的作用力发生转移而降低玻璃化温度。添加增塑剂可以降低高聚物物的玻璃化温度,增强聚合物的柔韧性、耐冲击蛋度和延伸率等物理性能。増塑剂的条件要求与树脂具有良好的相容性;化学稳定性好,要求耐温、耐光、耐水和耐化学药品性能好;其有良好的绝缘性和阻燃性;对颜料和填料的润湿性好,挥发性低;价格便宜,来源丰富。
增剂的品种可分为类增塑剂、氣烃类增塑剂和其他类。临类增塑剂又可分为邻苯二甲酸酯类、磷酸酯类、癸二酸酯类和环氧
酯类。邻邻苯二甲酸酯类增塑剂的优点是与树脂的相容性好,增塑效果明显,挥发率低,其耐寒性随醇类碳链的增长而提高,其有较好的耐泛黄性。癸二类增塑剂的优点是刚寒性好,可用于与食品接触材料的生产,增塑效果明显,挥发率低。缺点是价格比较贵嗨酸类增塑剂的优点是阻燃性能好,磷酸三甲酚睛只有防霉性能,电性能好。缺点是较容易变黄,耐光、耐热老化性差。环氧酶类塑剂的优点是涂膜的时热、耐光性好,不易泛黄,与树脂的相容性好,有良好的润性能,无毒,可用于与食品接触材料的生缺点是价格高。氯化烃类增塑剂的优点是具有优良的耐酸、耐碱、耐水性能和阻燃性能。
The use of plasticizers will improve the disadvantages of hard and magic powder coatings, and can give some such as flame retardancy, aging, flexibility, impact resistance and elongation . In order to give full play to the role of plasticizers, it is necessary to select the appropriate , and different types of plasticizers can be used together, which is more conducive to complementary advantages or synergistic effects. Generally, the amount of plasticizer used in thermoplastic powder coatings is relatively large, and the amount used in thermosetting powder coatings is very small. The amount added to the formula is 1% to 25%, and it is dispersed by melt extrusion mixing method.
