聚己内酯/酯化淀粉/纳米碳酸钙复合材料的制备及性能

以玉米淀粉(ST)和马来酸酐为原料,采用干法改性方法制备了酯化淀粉(EST),将EST与聚己内酯(PCL)、纳米碳酸钙通过密炼机混炼制备可降解PCL/EST/纳米碳酸钙复合材料。利用红外光谱仪、扫描电子显微镜、广角X射线衍射仪和热重-差示扫描量热同步热分析仪研究了PCL/EST/纳米碳酸钙复合材料的微观形态、力学性能、结晶以及热性能。结果表明,随着纳米碳酸钙含量的增加,PCL/EST/纳米碳酸钙复合材料的拉伸强度先升高后降低,当纳米碳酸钙含量为6份(质量份数,下同)时材料的拉伸强度和断裂伸长率达到最大值,与未添加纳米碳酸钙的复合材料相比分别提高了49.8%和34.8%;与PCL/ST/纳米碳酸钙复合材料相比,PCL/EST/纳米碳酸钙复合材料中淀粉颗粒尺寸减小,复合材料的熔点和结晶度有所提高,拉伸强度和熔体流动速率增加,热分解温度下降。

Preparation and Properties of Polycaprolactone/Esterified Starch/Nano-calcium Carbonate Composites

The corn starch was esterified with maleic anhydride via a dry process,which was blended with polycaprolactone(PCL),nano-calcium carbonate(nano-CaCO3) forming the composites.Mechanical properties,morphology,crystallization behavior and thermal properties of the composites were investigated using Fourier transform infrared spectroscopy,mechanical test,melt flow rate,scanning electron microscopy,wide-angle X-ray diffraction,and simultaneous thermogravimetry differential scanning calorimetry.It showed that the tensile strength and elongation at break of the composites first increased and then decreased with the increasing content of nano-CaCO3,and reached maxima when the content of nano-CaCO3 was 6 phr,49.8 % and 34.8 % higher than CaCO3-free samples,respectively.When esterified starch was used in the composites,melting point,crystallinity,tensile strength,and melt flow rate became higher,however decomposition temperature was a little lower.