超微淀粉在LDPE中分散性及其共混体系性能研究

STUDY ON DISPERSIBILITY OF MICRONIZED STARCH IN LDPE AND PROPERTIES OF THE BLEND

研究了平均粒径 2 .91μm的超微淀粉偶联改性后在 LDPE中的分散 ,及其共混物熔体流变性和超微淀粉 / LDPE膜的力学性能。结果表明 ,超微淀粉的偶联量可达 1%。超微淀粉 / L DPE熔体为非牛顿假塑性流体 ,随着剪切速率的提高 ,熔体表观粘度降低 ;随着淀粉粒径的减小 ,熔体流动性得到改善。超微淀粉 / LDPE膜中淀粉质量分数可达 5 0 % ,拉伸强度达 15 .6MPa,断裂伸长率为 4 69%。SEM显示超微淀粉在

The dispersibility of micronized starch (2.91 μm) treated by coupling agent in LDPE was evaluated. And the rheological property of the blend and the mechanical properties of starch/LDPE film were studied. The result shows that the coupling rate may be attainable 1%. The blend melts are pseudoplastic fluids. When the stress sheer increases, the apparent viscosity decreases. When the diameter of starch decreased, the rheological property of the blend melts was improved. The content of starch in the micronized starch/LDPE film reached 50%. Its tensile strength was 15.6 MPa, and its breaking elongation was 469%. The dispersity of the micronized starch in LDPE was proved to be excellent by SEM.