以羟丙基交联淀粉为原料、甘油为增塑剂,采用双螺杆熔融挤出共混技术制备热塑性淀粉。在单因素试验的基础上,利用响应面分析法对影响热塑性淀粉挤出膨胀率的因素进行优化。结果表明:在甘油添加量30.7%,熔融区温度136.6℃,螺杆转动频率16.4Hz的工艺条件下制得热塑性淀粉的离模膨胀率为172.4%;同时,对制备的热塑性淀粉吹塑成膜,将其置于50%的湿度环境平衡24h后,测得膜的抗张强度10.1 MPa,断裂伸长率107.4%。

Thermoplastic starch was prepared with cross-linked hydroxypropyl starch by double screw extruder,glycerol was used as plasticizer.The factors that affected extrusion swell of thermoplastic starch were optimized by response surface based on the single factor experiment.The results showed that the best condition was : glycerol 30.7%,extruder temperatures 136.6℃ and rotational frequency 16.4Hz.under the above conditions,the expansion ration was 172.4%.Meanwhile,the thermoplastic starch was used in blowing models.After being stored for 24h at RH=50%,the tensile strength and elongation of TPS reached to 10.1 MPa and 107.4% respectively.