生物基工程聚酯弹性体对聚(3-羟基丁酸酯-co-3-羟基戊酸酯)的增韧改性研究

Toughening modification of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)by bio-based engineering polyester elastomer

针对聚(3-羟基丁酸酯-co-3-羟基戊酸酯)(PHBV)的晶体尺寸大、结晶度高、呈脆性等问题对其进行增韧改性,通过熔融共混法在PHBV中添加生物基工程聚酯弹性体(BEPE),制备了PHBV/BEPE共混物,经过测试流变性能、结晶性能、力学性能、热性能及微观形貌,对共混物的结构和性能进行分析和研究。结果表明,PHBV与BEPE之间的氢键作用、链缠结作用以及相似的主链结构使二者有更好的相容性和分散性,还可使PHBV球晶数量增多,球晶尺寸减小;当添加30%(质量分数,下同)BEPE时共混物的断裂伸长率和冲击强度最高,分别较PHBV提高了589.2%和149.4%;BEPE使共混物的结晶度逐渐降低;添加BEPE样品的冲击断面逐渐粗糙,发生了脆韧转变。

In this paper,the properties of poly(3-hydroxybutyrate-co-3-hydroxyvalerate)PHBV/bio-based engineering polyester elastomer(BEPE)compounds were studied through analyzing their rheological properties,crystallization properties,mechanical properties,thermal properties,and microstructure.The results indicated that the number of PHBV spherulites increased along with a decrease in their size due to the hydrogen bonding,chain entanglement,and similar main chain structures between PHBV and BEPE,resulting in better compatibility and dispersion.When 30 wt%BEPE was added,the compounds achieved maximum elongation at break and impact strength,increasing by 589.2%and149.4%,respectively,compared to pure PHBV.The crystallinity of the compounds decreased with the addition of BEPE,and their impact fracture surface tended to be rough along with a“brittle-ductile”transition according to the morphological observation.