PET-co-PGA共聚酯的性能及可纺性研究

Preparation and spinnability of PET-co-PGA copolyesters

聚乙醇酸酯(PGA)在自然环境下快速降解而不易储存,难以进一步开发利用,共缩聚成为抑制其降解的重要途径之一。本文将对苯二甲酸(TPA)、乙二醇(EG)与PGA进行熔融缩聚反应而生成共聚酯(PET-co-PGA),探讨了PET-co-PGA基本性能以及碱降解性,研究了PET-co-PGA及纳米粒子改性共聚酯的熔纺性。试验结果表明:当PET-co-PGA中PET含量为87%时,特性黏度为0.805 dL/g,端羧基含量为38.7 mmol/kg,玻璃化温度为64.8℃,熔点为185.0℃,结晶度为2.8%。用2M NaOH水溶液于80℃下处理4 h后,共聚酯碱降解率为82.4%。共聚酯纤维断裂强度为1.4 cN/dtex,纤度为19.4 dtex。添加质量分数1.5%纳米TiO2后,改性共聚酯断裂强度为1.5 cN/dtex,纤度为10.6 dtex,PET-co-PGA表现出良好的熔纺性。共聚酯粉碎和纳米粒子增强改性均改善了共聚酯可纺性。

Polyglycolic acid ester(PGA)is not easy to store and find applications because of its fast degradation in natural environment.The copolyester PET-co-PGA was synthesized by melt polycondensation and transesterification with terephthalic acid,ethylene glycol and PGA.The basic properties of PET-co-PGA copolyester,such as intrinsic viscosity,carboxylic content,crystallization and alkali degradation were discussed.The melt spinning performances of the copolyester and the nanoparticle-dosed one were investigated.The results showed that the copolyester intrinsic viscosity was 0.805 dL/g,the end carboxyl content was 38.7 mmol/kg,while its color values were L 37.44,a 12.9,b 31.66 at the content of PET 87%.The glass transition temperature was 64.8℃,the melting point was 185.0℃and the crystallinity was 2.8%.The alkaline degradation rate of the copolyester was 82.4%whereas that of pure PET was 10%after being treated with 2 M NaOH solution at 80℃for 4 hours.The tensile strength of the fiber drawn at 65℃was 1.4 cN/dtex at its denier of 19.4 dtex.After being dosed 1.5%nano-TiO2 and drawn at 75℃,the tensile strength was 1.5 cN/dtex at the denier of 10.6 dtex.The spinnability of the copolyesteris improved by grinding and adding nanoparticles.