玻璃纤维增强TPVA/PBST复合材料的制备及性能

Preparation of glass fiber reinforced TPVA/PBST composites and their properties

研究了短玻璃纤维(SGF)增强热塑性聚乙烯醇(TPVA)/聚丁二酸对苯二甲酸丁二醇酯(PBST)复合材料的改性机理、复合材料的热学及力学性能,并对复合材料中玻璃纤维(GF)的尺寸及分布进行了分析。实验结果表明,马来酸酐接枝乙烯-乙酸乙烯酯共聚物(EVA-g-MAH)与硅烷偶联剂能够有效增容TPVA/PBST复合材料,引入EVA-g-MAH有利于提高组分之间的相容性和复合材料的韧性,而SGF则赋予复合材料优异的热稳定性;SGF用量增加,复合材料的拉伸强度、弯曲强度及模量提高,熔融流动性下降,韧性和断裂伸长率降低,复合材料在SGF用量为20.0%~30.0%(w)时发生韧-脆转变。SGF用量低时,复合材料中GF的平均尺度较大、分布较窄,可诱导TPVA结晶;SGF用量高时,GF的平均尺度减小、分布变宽,易导致TPVA结晶不完全或缺陷。

The modification mechanism,thermal and mechanical properties of short glass fiber(SGF)reinforced thermoplastic polyvinyl alcohol(TPVA)/poly(butylene succinic-co-terephthalate)(PBST)composites were investigated.The size and distribution of glass fibers(GF)in the composites were also analyzed.The experimental results revealed that the compatibility between components and the toughness of the TPVA/PBST composite system are effectively improved by incorporating maleic anhydride grafted ethylene-vinyl acetate copolymer and silane coupling agent,while SGF contributes to the excellent thermal stability of the composites.With the increase of SGF content,the tensile strength,flexural strength and modulus of the composites increase,while the melt flow rate,toughness and elongation at break of the composites decrease,and there is a ductile-brittle transition on the composites around 20%-30%(w)of SGF content.At a low SGF content,GF in the composites with larger average size and narrow size distribution can induce the crystallization of TPVA,while at a high SGF content,GF in the composites with smaller average size and broad size distribution may cause incomplete or defective crystallization of TPVA.