Effect of Starch/Polylactic Acid Ratio on the Interdependence of Two-Phase and the Properties of Composites  

作　　者：左迎峰 GU Jiyou CAO Jun WEI Shuangying TAN Haiyan 张彦华 

机构地区：[1]Key Laboratory of Bio-Based Material Science and Technology, Northeast Forestry University, Ministry of Education [2]College of Material Science & Engineering, Central South University of Forestry & Technology

出　　处：《Journal of Wuhan University of Technology(Materials Science)》2015年第5期1108-1114,共7页武汉理工大学学报（材料科学英文版）

基　　金：Funded by the National Forestry Public Welfare Industry Major Projects of Scientific Research(No.201504502);National Natural Science Foundation of China(No.31200442);Supported by the Post Doctorate Research from the Ministry of Science and Technology of China(No.2014M550178)

摘　　要：Starch/polylactic acid(PLA) composites were prepared by melt extrusion, with corn starch and PLA as raw materials, glycerol as the plasticizer. Effects of starch/PLA ratio on the interdependence of two-phase and other properties of the composites were studied. The combination of results of TGA with SEM indicated that the interdependence between starch and PLA was increased gradually as the starch/PLA ratio reduced. DSC results showed that the glass transition temperature(Tg), melting temperature(Tm) and degree of crystallinity of PLA in composites were increased gradually, whereas the cold crystallization temperature(Tc) was gradually decreased as the starch/PLA ratio reduced. The rheological properties of composites were closely related with the interdependence of two-phase, with reducing starch/PLA proportion, the interdependence was increased, and then the strain for storage modulus was firstl reduced and then gradually increased. Frequency scanning showed that the storage modulus and complex viscosity were decreased with reducing starch content. As the starch/PLA ratio reduced, the matrix phase PLA was increased, so that the strength of composites was increased gradually, whereas water absorption rate was decreased gradually.Starch/polylactic acid(PLA) composites were prepared by melt extrusion, with corn starch and PLA as raw materials, glycerol as the plasticizer. Effects of starch/PLA ratio on the interdependence of two-phase and other properties of the composites were studied. The combination of results of TGA with SEM indicated that the interdependence between starch and PLA was increased gradually as the starch/PLA ratio reduced. DSC results showed that the glass transition temperature(Tg), melting temperature(Tm) and degree of crystallinity of PLA in composites were increased gradually, whereas the cold crystallization temperature(Tc) was gradually decreased as the starch/PLA ratio reduced. The rheological properties of composites were closely related with the interdependence of two-phase, with reducing starch/PLA proportion, the interdependence was increased, and then the strain for storage modulus was firstl reduced and then gradually increased. Frequency scanning showed that the storage modulus and complex viscosity were decreased with reducing starch content. As the starch/PLA ratio reduced, the matrix phase PLA was increased, so that the strength of composites was increased gradually, whereas water absorption rate was decreased gradually.

关 键 词：corn starch polylactic acid mixing ratio interdependence of two-phase PROPERTIES 

分 类 号：TQ317[化学工程—高聚物工业] TB332[一般工业技术—材料科学与工程]