聚乙丙交酯和二乙酸纤维素化学共混物的制备和初步表征

以辛酸亚锡(SnOct2)为催化剂,将溶有二乙酸纤维素(CDA)的乙/丙交酯 (GA/LLA)熔体进行开环接枝反应,制得二乙酸纤维素和聚乙丙交酯的共混物,并提纯得到接枝共聚物CDA-g-Poly(LLA-co-GA)s.用IR和GPC对提纯所得接枝共聚物进行了初步表征,用TGA和DSC对共混物的玻璃化温度、熔点和热失重行为进行了测定,并与相应的机械共混物进行了比较.结果表明,接枝共聚物具有较短的聚L-丙交酯(PLLA)和聚乙交酯(PGA)侧链.共混物具有较好的热稳定性,玻璃化温度和熔点可通过改变投料比调节.通过化学接枝反应所得共混物的性能与机械共混物不同的原因可能是由于PLLA和PGA侧链的内增塑作用.

Preparation and preliminary characterization of chemical blends of poly(glycolide-co-L-lactide)s and cellulose diacetate

Blends of poly(glycolide-co-L-lactide)s and cellulose diacetate(CDA) were prepared by ring-opening graft polymerization of glycolide/L-lactide on cellulose diacetate,using stannous octoate(SnOct_2) as catalyst.The purified graft copolymers were preliminarly characterized by IR and GPC.Thermogravimetic behavior,glass-transition temperature and melting point of the chemical blends were measured by TGA and DSC,and still compared with those of mechanical blends.The results showed that the graft copolymers had short PLLA and PGA lateral chain.The blends had better thermal stability and its glass-transition temperature and melting point can be adjusted by varying the feed ratio.The behavior difference between mechanical blends and blends prepared by chemical grafting reaction was possibly caused by the internal plasticization of short PLLA and PGA lateral chain.