聚乙二醇改性淀粉与PBAT复合材料的制备和性能

Preparation and Performance of Polyethylene Glycol Modified Starch/PBAT Composite

普通淀粉由于具有微晶束结构,与聚合物树脂相容性较差,影响了淀粉在聚合物改性中的应用。采用六偏磷酸钠(SHMP)和聚乙二醇(PEG)对淀粉进行改性,然后,采用改性淀粉与聚己二酸/对苯二甲酸丁二酯(PBAT)熔融共混挤出,制备得到复合材料,进行红外光谱分析与热失重测试。结果表明,SHMP和PEG成功的对淀粉进行了改性。当SHMP和PEG添加量均为10%时,改性淀粉的热稳定性最佳,热分解温度达到300℃。通过对改性淀粉/PBAT复合材料进行力学性能、吸水性能测试可知,当SHMP和PEG的添加量均为5%时,制备的改性淀粉与PBAT的相容性较好,得到的复合材料拉伸强度可达6.5 MPa,断裂伸长率为145%,并且所制备的复合材料具有较低的吸水率。

Because of the microcrystalline bundle structure,starch exhibits the poor compatibility with polymer matrix,which limits its application in the modification of polymer.In this work,starch was modified by sodium hexametaphosphate(SHMP)and polyethylene glycol(PEG)in the gelatinization process firstly,and then was blended with polybutylene terephthalate(PBAT)to prepare the starch/PBAT composite.The infrared spectrum analysis and the thermogravimetric curve showed that the starch was successfully modified by SHMP and PEG.When the addition of SHMP and PEG was 10%,the better thermal stability of the modified starch was achieved,and the thermal decomposition temperature reached 300℃.Furthermore,the tensile strength and the water absorption of the obtained composite were measured.When the modified starch prepared with the addition amounts of SHMP and PEG was 5%was added,the compatibility of starch and PBAT was improved,and then the tensile strength of the as⁃obtained composite was 6.5 MPa,and the elongation at break reached 145%.Moreover,a good water resistance was obtained.