粉末涂料用耐高温有机硅改性聚酯树脂的制备和性能研究

Preparation and Properties of High Temperature Resistant Silicone Modified Polyester Resin for Powder Coatings

通过化学共聚改性的方法在粉末涂料聚酯树脂中引入有机硅,合成了粉末涂料用有机硅改性聚酯树脂,研究了有机硅中间体用量对改性聚酯树脂黏度、相对分子质量及其分布、玻璃化转变温度和热失质量的影响。并用其制备了平面和消光2种粉末涂料,研究了不同有机硅中间体加量对涂层性能的影响。结果表明:有机硅中间体加量为42%的改性聚酯树脂具有合适的玻璃化转变温度和黏度,制备的粉末涂层具有良好的附着力;在350℃左右的高温下平面涂层具有优秀的保光率,加入云母粉的消光涂层则具有更好的弯曲性能。有机硅改性聚酯树脂在兼顾耐热性和平面高光的同时,又解决了使用纯有机硅树脂的价格偏高的问题,为市场提供了耐高温粉末涂料用聚酯树脂的更多选择性。

In this paper,silicone was incorporated into polyester resin by chemical copolymerization,which was used for powder coatings.The effects of the amount of silicone intermediate on the viscosity,relative molecular weight and its distribution,glass transition temperature and thermal weight loss of modified polyester resin were studied.Two kinds of powder coatings,high gloss finish and matt finish,were prepared.The effects of different amount of silicone intermediate on the coatings properties were studied.The results showed that the modified polyester resin with 42% silicone intermediate provided appropriate glass transition temperature and viscosity,and the powder coating prepared by this modified polyester resin presented good adhesion and excellent gloss retention at about 350℃.In addition,the matt coatings with mica exhibited better bending properties.This resin offered high temperature resistance and high gloss,and solved the high price drawback of using pure silicone resin at the same time,which also provided more options of polyester resins for high temperature resistant powder coatings in the market.