无机盐增塑淀粉/聚乙烯醇共混复合材料的结构与性能研究

This project aims at establishing new principle and new methods for preparing starch/PVA blend or composite materials with high performance to meet the urgent need of developing natural and non-petroleum based environment friendly polymers. Inorganic salts containing high electrovalent metal ions such as Mg2+, Ca2+ would be used as the high-effeciency plasticizers for starch/PVA in place of the commonly used small organic molecules such as glycerol and water. These metal ions can form strong electronic interaction with the oxygen in starch and PVA molecules and thus realize the plasticization of starch/PVA and improve compatibility of starch and PVOH. With these high-effeciency plasticizers it can be easier to tailor the structure and properties of starch/PVA blend or composite materials materials and realize the thermal processing of starch/PVA than that by suing common plasticizers such as glycerol. Based on these new plasticizers for starch/PVA, the crosslinking and reinforcing with inorganic fillers etc methods would also be used to prepare the high-performance starch/PVA blend or composite materials materials. The basic plasticization principle of inorganic salts on starch/PVA and the effect of different kinds of inorganic salt and concentration on the properties of starch/PVA blend or composite materials would be researched. The effect of inorganic salts with different structures on the aggregation structure, thermal properties and crystallization behaviors would be researched. It is also anticipated to prepare the high performance starch/PVA environment friendly materials by thermal processing through this project.

本项目以环境友好高分子材料- - 淀粉/聚乙烯醇（PVA）共混复合材料为研究对象，针对现有增塑剂与淀粉/PVA体系相容性较差、增塑效果不理想，制备的材料性能较差的问题，创新增塑方法，采用无机盐为增塑剂，即以高价金属离子与淀粉/PVA中氧原子的强电子相互作用替代现有增塑剂的氢键作用，改变高分子链段的活动性和聚集态结构，提高共混体系的相容性。研究不同结构的无机盐对淀粉/PVA共混体系结构与性能的影响规律，建立高效且能赋予制品优良性能的淀粉/PVA热塑加工新技术。在此基础上采用交联改性及与无机填料、纤维复合的方法进一步改善材料性能，研究相关改性方法的作用原理，揭示淀粉与PVA结构、体系组成、成型加工条件、交联与复合改性对无机盐增塑的淀粉/PVA体系结构、性能的影响规律，建立淀粉/PVA共混复合材料的结构与性能调控方法，为制备能满足不同应用要求的高性能淀粉/PVA共混复合材料奠定基础。

淀粉、PVA及其共混复合材料是很有发展前景的环境友好材料。本项目针对现有增塑剂与淀粉/PVA体系相容性较差、增塑效果不理想，制备的材料性能较差的问题，创新增塑改性方法，围绕盐增塑改性淀粉、PVA共混复合材料认真按计划开展研究工作，取得了系统的研究成果，完成了研究计划，达到了预期目标：1）研究了锂盐、镁盐、钙盐、铝盐（配对阴离子包括Cl—、NO3—）及有机盐1-丁基-3-甲基咪唑氯盐[BMIM]Cl（离子液体）等不同结构的盐类物质与淀粉、PVA及其共混物的相互作用原理及改性体系的结构性能特征，揭示了盐的作用机理及不同结构盐对淀粉/PVA结构与性能的影响规律；2）研究了氯化镁与甘油在改性淀粉/PVA中的复合作用，采用氯化镁复配改性剂实现了PVA及淀粉/PVA的熔融挤出，揭示了氯化镁复配改性剂与淀粉/PVA的作用效果与规律，为发展PVA及淀粉/PVA热塑加工新技术、制备不同性能的淀粉/PVA共混复合材料奠定了基础；3）研究了淀粉及PVA结构对无机盐增塑改性的淀粉/PVA体系结构与性能的影响，获得了相关规律；4）针对氯化镁/甘油改性的淀粉/PVA共混材料，进一步开展了交联改性及与纳米材料的共混改性研究，获得了交联改性材料及纳米共混复合材料的结构与性能特征，为实现改性淀粉/PVA的性能调控奠定了基础；5）发表期刊论文10篇、会议论文4篇、申请发明专利1项，培养博士研究生2人、研究生硕士5人。