甘油用量对淀粉/聚乳酸复合材料性能的影响

摘要

Starch/polylactic acid composites were prepared by melt extrusion method with corn starch and poly-lactic acid as raw material,glycerol as the plasticizer.Melt fluidity,interfacial compatibility,mechanical prop-erties,water absorption rate and rheological properties of composite was studied by glycerol content.The re-sults show that the increased glycerol content was increased melt flow properties of composite materials,and reduce the complex viscosity,which helps to improve the processing performance of the composite material. The addition of glycerol increased the interface compatibility between starch and polylactic acid,and with glyc-erol content increased,the compatibility was improved more.Compatibility improve was increased the tensile strength of the composite.Plasticizer can damage the crystalline structure of starch,reduce the interaction of molecules,and so increase flexibility of composite material.Thus,with glycerol dosage increase,the bending strength and storage modulus were decreased,but the elongation at break increased.Water absorption test re-sults show that increased glycerol dosage was help to improve the water resistance of composite materials.%以玉米淀粉和聚乳酸为原料，甘油为增塑剂，利用熔融挤出法制备了淀粉/聚乳酸复合材料。研究了甘油用量对复合材料熔融流动性、界面相容性、力学性能、吸水率以及流变性能的影响。结果表明，甘油用量增加可以提高复合材料的熔融流动性能，降低复数粘度，有利于提高复合材料的加工性能。甘油的加入提高了淀粉和聚乳酸的界面相容性，并且甘油用量增加，相容性提高越多。相容性提高使复合材料的拉伸强度提高。增塑剂能够破坏淀粉的结晶结构，降低分子间相互作用力，提高复合材料的柔顺性。随着甘油用量增加，淀粉/聚乳酸复合材料的弯曲强度降低，储能模量也逐渐降低，但断裂伸长率增大。吸水率测试结果表明，甘油用量增加有利于提高复合材料的耐水性能。