PEG对PLA/PBS共混物结构与性能的影响

Effect of PEG on Microstructure and Properties of PLA/PBS Blend

通过熔融共混法制备了聚乳酸/聚丁二酸丁二醇酯/聚乙二醇(PLA/PBS/PEG)共混物,研究了PEG组分对PLA/PBS共混体系微观结构、流变性能、结晶性能、动态力学性能以及冲击性能的影响。结果表明,将PEG组分添加到PLA/PBS共混物中,能够降低PBS分散相的尺寸,均化分散相尺寸分布,增强界面结合。与PLA/PBS共混物相比,PLA/PBS/PEG共混物的复数黏度大幅度降低。由于PEG对PLA和PBS分子链同时具有增塑作用,使PLA/PBS/PEG共混物的结晶能力远大于相应的PLA/PBS共混物,最高结晶度可达17.4%。通过测试,动态力学性能结果表明,PEG组分能够降低共混体系中PLA组分的玻璃化转变温度,并且促进PLA与PBS之间的相容性。此外,PLA/PBS/PEG共混物的冲击强度得到了显著提高,最高可达到4.71 k J·m-2,比未添加PEG组分的PLA/PBS共混物提高了25.3%。

Poly(lactic acid)/poly(butylene succinate)/poly(ethylene glycol)(PLA/PBS/PEG)triple-phase blends were prepared by melt blending.The influences of PEG component on the microstructure,rheological properties,crystallization properties,dynamic mechanical properties and impact properties of PLA/PBS blends were studied.The results showed that the addition of PEG component could reduce the size and homogenize the size distribution of dispersed phase,enhance the interfacial adhesion.Compared with PLA/PBS blends,the complex viscosity of PLA/PBS/PEG blends were reduced sharply.Own to the plasticization effect of PEG on PLA and PBS,the crystallization capacity of PLA/PBS/PEG blends were much higher than that of corresponding PLA/PBS blends.The highest crystallinity of 17.4%was achieved.The results of dynamic thermomechanical properties showed that PEG components could reduce the vitrification transition temperature of PLA components in the blend system and promote the compatibility between PLA and PBS.Moreover,the impact strength of PLA/PBS/PEG blends were improved significantly.The highest value of 4.71 k J·m-2 was reached,which increased by 25.3%compared with PLA/PBS blend without PEG component.