聚乳酸/聚丁二酸丁二醇酯/二氧化碳基热塑性聚氨酯三元薄膜的制备与性能研究

Study on Preparation and Properties of PLA/PBS/Thermoplastic Poly(propylene carbonate) Polyurethane Blown Films

用熔融共混法和挤出吹膜工艺制备了聚乳酸(PLA)/聚丁二酸丁二醇酯(PBS)/二氧化碳基热塑性聚氨酯(PPCU)薄膜。用差示扫描量热仪(DSC)、力学测试、流变测试和接触角分别详细研究了PLA/PBS/PPCU共混体系的结晶性能、力学性能、流变学特性和亲水性。DSC结果分析表明PLA与PBS的结晶可互相抑制,共混体系总结晶度下降,有利于薄膜的韧性提高。力学结果表明PPCU对PLA改性效果好,显著提高其力学性能。而PBS的加入进一步改善了PLA的柔韧性,断裂伸长率更高,杨氏模量下降显著。PBS的加入使体系黏度降低,增加流动性。PBS对改善共混薄膜亲水性有一定作用。

Poly （ lacticacid ） （ PLA ）/poly （ butylene succinate ） （ PBS ）/poly （ propylene carbonate ） polyurethane （PPCU） film was prepared by melt blending method and extrusion blown film process. By using differential scanning calorimetry （DSC）, mechanical testing, rheological testing and contact angle testing, the crystallization properties, mechanical properties, rheological behaviors and hydrophilic properties of PLA/PBS/PPCU blend films were investigated in detail. The results of DSC indicated that PLA and PBS had inhibiting effect on each other in crystallization and total degree of crystallinity, which benefited to improve the toughness of PLA/PBS/PPCU film. The results of mechanical properties indicated that PPCU has good modification effects and it could improve mechanical properties significantly. The addition of PBS could improve the flexibility of PLA/PBS/PPCU film ulteriorly. The elongation at break is greatly enhanced and Young＇s modulus decreases significantly. The addition of PBS could decrease viscosity of blend system and increase mobility of blend system. PBS has certain effect on improvement of hydrophilic properties.