生物降解塑料填充增强复合体系的流变学研究

We study the rheological properties, rheological models and the enhancement mechanism of biodegradable plastic composites with plant fiber or inorganic nanoparticle as the filler in this project. As we known, the biodegradable plastics cannot be used widely for their high costs and low intensities. We will (1) improve the self-developed multi-functional rheological instrument and create an experimental platform for testing the rheological properties of biodegradable composites with plant fiber or inorganic nanoparticle filler. (2) research the effects of the filler content, filler size, shear rate, processing temperature, superimposed force field, compatibilizer, modifier and other factors on the rheological behaviors, the product structures and performances of the composites, then set up the rheological models for biodegradable plastic composites in typical processing field. (3) explain the dispersal mechanism and the orientation of plant fiber or inorganic nanoparticle in the biodegradable plastic matrix, which induce the crystallization and enhance the biodegradable plastics. The above-mentioned researches can explain the nonlinear viscoelastic behaviors of biodegradable plastic composites, and can optimize the material formula, processing technologies and molding equipment for biodegradable plastic composites in order to reduce the production costs and to improve the processing performance and the product intensity of biodegradable plastic composites.

针对生物降解塑料普遍存在的生产成本高、制品强度低等不足，分别选取生物降解塑料/植物纤维复合体系、生物降解塑料/无机纳米粒子复合体系为研究对象：（1）结合植物纤维、无机纳米粒子、生物降解塑料的特点，完善自行研制的多功能流变特性测试仪器，建立测试生物降解塑料填充增强复合体系流变行为的实验平台。（2）研究填料含量、填料尺寸、剪切速率、加工温度、叠加外场、相容剂或改性剂含量等因素对复合体系流变行为和制品结构性能的影响规律，建立多因素影响下生物降解塑料填充增强复合体系在典型加工流场中的流变模型。（3）宏观实验表征和微观动力学相结合，研究植物纤维、无机纳米粒子在生物降解塑料基材中分散、取向、诱导结晶以及增强生物降解塑料的机理。上述研究为客观而合理地建立生物降解塑料填充增强体系非线性粘弹行为的表征理论，优化体系的配方设计、加工工艺和成型设备，以降低生产成本、提高制品强度，提供重要的理论基础和实验依据。

针对生物降解塑料普遍存在的生产成本高、制品强度低等不足，以生物降解塑料填充改性复合体系为研究对象：（1）结合无机纳米粒子、微晶纤维素等改性填料以及生物降解塑料的特点，完善了自行研制的多功能流变特性测试仪器，建立了测试生物降解塑料填充改性复合体系流变行为的实验平台。（2）研究了填料含量、填料尺寸、剪切速率、加工温度、叠加外场、相容剂或改性剂含量等因素对复合体系流变行为和制品结构性能的影响规律，分析了多因素影响下生物降解塑料填充增强复合体系在典型加工流场中的流变特性和机理。（3）宏观实验表征和微观动力学相结合，研究了无机纳米粒子、微晶纤维素等改性填料在生物降解塑料基材中分散、取向、诱导结晶以及增强生物降解塑料的机理。上述研究为客观而合理地建立生物降解塑料填充增强体系非线性粘弹行为的表征理论，优化体系的配方设计、加工工艺和成型设备，以降低生产成本、提高制品强度，提供重要的理论基础和实验依据。此外，依托本项目开发的流变测试平台和流变分析方法，拓展了高流动性尼龙和共聚尼龙填充改性复合材料的流动机理分析及其对实际生产中材料配方设计和成型加工工艺的指导。