PLA/PBS共混物增黏改性的研究

Study on Viscosity Increasing Modification of PLA/PBS Blends

采用熔融反应共混法,通过引入过氧化二苯甲酰(BPO),对聚乳酸/聚丁二酸丁二醇酯(PLA/PBS)进行增黏改性。研究了该PLA/PBS反应共混物的流变性能、凝胶分数、热性能、力学性能和断面微观形貌。结果表明:随着BPO用量的增加,PLA/PBS反应共混物的转矩和凝胶分数均增大;PLA/PBS反应共混物的结晶性和熔点(Tm)随着BPO用量的增加而降低,且出现熔融双峰,当BPO用量增至1 phr时,熔融双峰消失,PLA和PBS间的相容性显著改善;随着BPO用量的增加,PLA/PBS反应共混物的断裂伸长率、拉伸强度、冲击强度均有所提高,而玻璃化转变温度(Tg)先降后升,体系的内耗则逐渐降低。

The poly（lactic acid）/poly（butylene succinate）（PLA/PBS） blends with benzoyl peroxide（BPO） were prepared by reactive blending,and the rheological properties,gel fraction,thermal properties,mechanical properties and morphological structure of the blends were investigated.The results show that torque and gel fraction of the blends increase with increasing BPO contents.The crystallization ability and the melting point（Tm） decrease with increasing BPO contents,and there are double melting peaks on differential scanning calorimetry（DSC） thermograms.In addition,the double melting peaks disappear while BPO contents increase to 1%,and the compatibility between PLA and PBS improves significantly.Elongation at break,tensile strength,impact strength of the reactive PLA/PBS blends enhance,but the glass transition temperature（Tg） decreases first and then increases,and internal friction of the PLA/ PBS blends reduces gradually with increasing BPO contents.