主链含硅的芳香嵌段共聚酯的制备

Preparation of main-chain silicon-containing aromatic polyester block copolymers

通过酯交换、熔融缩聚的方法将含硅耐热单元引入到聚对苯二甲酸丙二醇酯-聚四亚甲基醚二醇大分子链中,制备了一系列硅含量不同的嵌段共聚酯,并对其结构、特性黏数、熔融和结晶性能、热稳定性能以及燃烧后试样形态进行了表征和分析。结果表明:通过熔融缩聚可以合成含硅嵌段共聚酯;含适量硅组分的共聚酯具有良好的结晶性能,更高的热稳定性,有一定的阻燃性;随着主链中硅含量的增加,共聚酯的熔点降低,起始结晶温度和残炭量均升高,当硅油质量分数为7%时,冲击强度提高了2.5倍。

Heat resistant blocks containing silicon were introduced to polytrimethylene terephthalatepolytetramethylene ether glycol(PTT-PTMEG)via ester exchange and melt polycondensation to prepare a series of block copolyesters in different silicon contents.The block copolyesters were characterized in terms of the structure,characteristic viscosity,thermal stability,melting and crystallization properties as well as morphology of samples after combustion.The results show that silicon-containing block copolyesters are synthesized by melt polycondensation,which performs excellently in crystallization,thermal stability and flame retarding.The melting point descends while the initial crystallization temperature and carbon residue ascend with the increase of silicon content in main chains of copolyesters.The impact strength of the copolymer is increased by 2.5 times when the mass fraction of silicon oil is 7%.