PBAT/热塑性玉米淀粉共混改性对结构和力学性能影响

采用价格低廉的玉米淀粉为填充剂来改性生物可降解聚己二酸?对苯二甲酸丁二酯（PBAT），以降低PBAT价格，拓宽应用领域。首先采用丙三醇对玉米淀粉进行塑化，再采用双螺杆挤出机进行造粒获得热塑性淀粉（TPS）粒料，然后采用双螺杆挤出机和注塑机制备不同比例的PBAT/TPS样条，最后分析论文TPS含量对样条结构和力学性能的影响。结果表明，经丙三醇塑化后的淀粉含有大量的羟基，PBAT的结晶结构与PBT的相同，随着TPS含量的增加，PBAT的结晶完善程度逐渐降低，结晶温度向高温方向偏移，拉伸强度和断裂伸长率逐渐降低，而弹性模量有相反的趋势。

Effect of Blending Modification on Structure and Mechanical Properties of PBAT/Thermoplastic Corn Starch Composites

As a biodegradable thermoplastic, PBAT has some application limitations due to its high price. In this study, the low?cost corn starch was used as a filler to modify PBAT. The corn starch was first plasticized with glycerol and then extruded with a twin-screw extruder to obtain the thermoplastic corn (TPS) granules. PBAT/TPS composites were prepared at different ratios by melt blending, and the effect of TPS content on their structure and mechanical property was investigated. The results indicated that there were a large number of hydroxyl groups formed in the starch after plasticized with glycerol. PBAT exhibited the same crystalline structure with PBT. In the PBAT/TPS composites, the PBAT domain showed a gradual decrease in the level of crystallization perfection with an increase of TPS content, and meanwhile its crystallization temperature shifted to a high temperature. As the TPS content increased, the tensile strength and elongation at break of the composites decreased gradually but their elastic modulus tended to increase