聚乳酸/柠檬酸基聚酯共混物的降解性能  

Degradation of Polylactide/Citric Acid-Based Polyester Blend

作　　者：张伟阳[1] 桂宗彦[1] 徐媛媛[1] 陆冲[1] 程树军[1] 

机构地区：[1]华东理工大学材料科学与工程学院,上海200237

出　　处：《高分子材料科学与工程》2013年第10期32-35,共4页Polymer Materials Science & Engineering

摘　　要：采用熔融共混制备了聚乳酸/柠檬酸基聚酯(PLA/PEGCA)共混物(质量比85/15),通过对共混物在缓冲溶液中的失重率、吸水率、PLA相对分子质量、表面形貌和力学性能的测定,研究了其降解行为,并同纯PLA做了对比。结果表明,由于PEGCA的亲水性强,缓冲溶液容易渗透到材料内部,所以PLA/PEGCA共混物相对于纯PLA有更好的降解能力。12周时,PLA/PEGCA共混物的失重率与吸水率分别为0.8%和13.0%,明显大于纯PLA。共混物中PLA的组分相对分子质量下降程度大于纯PLA。随着降解时间的延长,共混物表面出现明显裂纹,力学性能降低,12周后冲击强度和拉伸强度分别为7.8 MPa和11.3 MPa,而纯PLA变化不大。A blend of poly（lactic acid） （PLA） and citric acid-based polyester （1SEGCA） （ mass ratio of 85/15） was prepared via melt blending. Mass loss, water absorption ratio, molecular mass of PLA, morphologies of the surfaces and mechanical properties of the blend were investigated during degradation in buffer solution. Neat PLA was tested as control. The results indicate that the mass loss and the water absorption of PLA/PEGCA after 12 weeks are 0.8% and 13.0% respectively, greater than those of PLA due to hydrophilic nature of PEGCA and the ease of the buffer solution to penetrate into the material. The molecular mass loss of PLA in PLA/PEGCA is.faster than that in neat PLA. During degradation, cracks appear in the surfaces of blends, which makes the mechanical properties decrease, the impact resistance and tensile strength are 7.8 MPa and 11.3 MPa respectively after 12 weeks, while those of neat PLA has a limited change.

关 键 词：聚乳酸 降解 柠檬酸基聚酯 共混物 

分 类 号：TQ316.62[化学工程—高聚物工业]