强韧化聚(3⁃羟基丁酸⁃co⁃3⁃羟基戊酸酯)/聚碳酸酯共混物的制备及耐久性研究

Study on preparation and durability of toughened poly(3⁃hydroxybutyrate⁃co-3⁃hydroxyvalerate)/polycarbonate blending films

以聚(3⁃羟基丁酸⁃co⁃3⁃羟基戊酸酯)(PHBV)作为基体,通过共混聚碳酸亚丙酯(PPC)后进行固相拉伸,制备强韧化PHBV/PPC复合薄膜;通过万能拉伸试验机、小角/广角X射线散射仪、场发射扫描电子显微镜、差示扫描量热仪对共混物进行表征。结果表明,当固相拉伸温度为55℃、拉伸速率为300 mm/min,拉伸倍率为3时,对比未拉伸样品,断裂伸长率提高约为66%,拉伸强度提高约为642.9%。当拉伸倍率为3时,取向度从0.88%提升到38.96%,还有效促进了聚合物的结晶,对PHBV的耐久性产生了正向作用,使得其性能更加稳定,对比未拉伸样品有了明显提升:未拉伸样品的韧性下降95%,固相拉伸3倍的样品的韧性下降46%。

The toughened poly(3⁃hydroxybutyrate⁃co⁃3⁃hydroxyvalerate)(PHBV)/polypropylene carbonate(PPC)blending films were prepared through solid⁃phase stretching and then characterized by using universal tensile testing machine,small⁃angle/wide⁃angle X⁃ray scattering instrument,SEM,and DSC.The PHBV/PPC blending films exhibited an increase in elongation at break by about 66%and in tensile strength by 642.9%at a stretching temperature of 55ºC,a stretching rate of 300 mm/min,and a stretching ratio 3.The degree of orientation of the blending films was increased from 0.88%to 38.96%at a stretching ratio of 3.This effectively promotes the crystallization of PHBV and generates a positive effect on its durability of PHBV,resulting in more stable performance.The toughness of the unstretched blending film decreased by 94.8%,whereas there was only a reduction by 46%in the toughness of the blending film at a stretching ratio of 3.