半芳香族耐高温聚酰胺的制备及性能

Preparation and Properties of Semi-Aromatic High-Temperature Resistant Polyamide

为满足电子电器、汽车涡轮增压发动机等对聚酰胺(PA)耐高温性能提出的更高要求,开发了一种能够获得各种黏度的耐高温聚酰胺(PA6T/66)树脂的工艺,该工艺简单,耗能低,环保安全。首先,利用熔融法和固相增黏法相结合的方式制备了不同黏度的PA6T/66,此时树脂黏度较高。其次,PA6T/66树脂在一定温度和真空度下增黏至所要求的黏度。探究了不同pH条件下制备的对苯二甲酸己二胺(6T)盐的形貌与颜色;研究了不同pH下制备的6T盐与己二酸己二胺(66)盐、聚合压力、聚合时间、封端剂用量、树脂增黏时间等对PA6T/66树脂相对黏度的影响。结果表明,各种pH条件下制备的无水6T盐为白色结晶状粉末;当6T盐与66盐质量比为55∶45时,PA6T/66树脂的熔点为307℃;聚合压力为2.35 MPa,聚合时间为3 h,封端剂占总盐质量0.1%,增黏时间为6 h时,制备的PA6T/66树脂达到玻纤增强、电子电器应用的要求。

In order to meet the higher requirements of high temperature resistance of polyamide(PA)in electronic appliances,automobile turbocharged engines,etc.,a process for obtaining high temperature resistant polyamide(PA6T/66)resin with various viscosities was developed.The process is simple,low energy consumption,environmental protection and safety.Firstly,PA6T/66 with different viscosities was prepared by combining melting method and solid-phase viscosity enhancement method,and the resin viscosity was high.Secondly,the resin was tackled to the required viscosity at a certain temperature and vacuum.The morphology and color of hexanediamine terephthalate(6T)prepared under different pH conditions were explored.The effects of 6T salt and hexamethylene adipate(66)salt prepared at different pH,polymerization pressure,polymerization time,amount of capping agent,and resin thickening time on the relative viscosity of PA6T/66 resin were studied.The results show that the anhydrous 6T salt prepared under various pH conditions is white crystalline powder.When the mass ratio of 6T salt to 66 salt is 55∶45,the melting point of the PA6T/66 resin is 307℃;When the polymerization pressure is 2.35 MPa,the polymerization time is 3 h,the end capping agent accounts for 0.1%of the total salt mass,and the tackification time is 6 h,the prepared PA6T/66 resin meets the requirements of glass fiber reinforcement and electronic and electrical applications.