聚乳酸/聚氧化乙烯共混体系的热行为和力学性能及流变行为  

THERMAL-MECHANICAL PROPERTIES AND RHEOLOGICAL BEHAVIORS OF POLYLACTIDE/POLY(ETHYLENE OXIDE) BLENDS

作　　者：贾智源[1] 韩常玉[1] 董丽松[1] 杨宇明[1] 

机构地区：[1]中国科学院长春应用化学研究所,长春130022

出　　处：《高分子学报》2009年第9期967-972,共6页Acta Polymerica Sinica

摘　　要：采用熔融共混方法制备了聚乳酸与聚氧化乙烯的共混物.细致研究了重均分子量分别为2 kDa、10kDa1、00 kDa和600 kDa的聚氧化乙烯对聚乳酸的改性效果,并使用DSC、DMA及旋转流变仪等分析了共混物的相容性、热行为、力学性能和流变行为.结果表明,在聚氧化乙烯的组分含量不超过20 wt%的前提下,共混体系保持为完全相容体系,当聚氧化乙烯的分子量超过10 kDa时,其对聚乳酸的增塑效果,不随分子量增加而降低;增加聚氧化乙烯的分子量,可以提高材料的弹性模量和熔体强度.Polylactide （ PLA ）/poly （ ethylene oxide ） （ PEO ） blends were prepared by melt-mixing, and the influence of molecular weight of PEO on the thermal-mechanical properties and rheological behaviors of the blends was investigated. Four kinds of PEO with molecular weight of 2 kDa （PEG2）, 10 kDa （PEG10）, 100 kDa （PEO100） and 600 kDa （PEO600） were used in this study. It was found that all PEOs were miscible with PLA to an extent of ca. 20 wt% and their quenched blends were completely amorphous. The decrease of Tg showed the plasticization effect of PEO on PLA. When the molecular weight of PEO was over 10 kDa, the plasticization effect was not dependence on the molecular weight of PEO, which did not decrease with the increase of molecular weight of PEO.Increasing the molecular weight of PEO can increase the tensile modulus and melt intensity of PLA/PEO blends, while the ductility of the blends was not decreased. All blends with 20 wt % PEO had a similar elongation at break of about 330% , but tensile moldulus of the blends changed from 250 MPa for the PLA/PEG2 blend to 550 MPa for the PLA/PEO600 blend. The theology experiments indicated the G′ increased significantly with the increase of molecular weight of PEO for the blends with same composition.

关 键 词：聚乳酸 聚氧化乙烯 增塑 流变行为 

分 类 号：TQ317[化学工程—高聚物工业]