聚乙烯醇热塑加工的研究

Thermal Processing of Poly(Vinyl Alcohol)

聚乙烯醇(PVA)是综合性能优异的可由非石油路线大规模生产的一种高分子材料,但其熔点与分解温度接近,难以热塑加工,应用主要基于溶液法,仅能制备纤维、薄膜等低维制品或用作助、辅材料,限制了其应用和发展。文中介绍了我们近年来在PVA热塑加工方面的一些研究工作:通过分子复合和增塑,获得PVA热塑加工窗口,实现PVA热塑加工,建立了PVA熔融纺丝、吹塑成膜、挤出注塑、中空吹塑及热塑发泡等新技术,通过热塑加工制备性能优良的PVA/无机填料复合材料和PVA/生物质复合材料,为开拓PVA应用新领域、解决PVA工业发展瓶颈问题提供新理论、新技术。

Poly（vinyl alcohol） （PVA） is an important polymer material that can be prepared in large industrial scale from coal and natural gas and has been developed very fast in recent years. However, the melting point of PVA is very close to its decomposition temperature, resulting in the difficulty in thermal processing of PVA. The current applications of PVA are based on and limited to wet process, only used as low-dimensional products such as fibers, films, or as assistants, and auxiliary materials, which seriously hinders the further development of PVA industry. This paper briefly reviewed our research work on the novel thermal processing technology of PVA and PVA based composites. Based on intermolecular complexation and plasticization, the thermal processing window of more than 120 ℃ for PVA was obtained. In this way, the melt spinning, thermal blowing, extrusion, injection and micro-injection molding as well as thermal foaming of PVA were successfully realized. Furthermore, the PVA based composites with excellent comprehensive properties such as PVA/inorganic filler and PVA/biomass material composites were obtained combining the thermal processing of PVA and solid state shear milling （S3M） technology, which will open a new application field for PVA and provide a technical and theoretical support for PVA industry.