采用超声辅助动态分散装置制备石墨烯纳米片/聚乙二醇(GNPs/PEG)复配改性剂,通过熔融共混法制备一系列GNPs/PEG/聚乳酸(PLA)复合材料,在120℃下对样品进行不同时间的退火处理。利用广角X-射线衍射仪(WAXD)和偏光显微镜(POM)分析了复配改性剂GNPs/PEG及退火对PLA结晶行为的影响。结果表明,GNPs/PEG的添加未改变PLA的晶型,随着退火时间的增加,纯PLA结晶的完善程度会进一步提高,GNPs/PEG的添加有利于缩短退火时间;退火30min时,GNPs/PEG/PLA复合材料的晶体较为完善,继续延长退火时间对其晶体形貌几乎没有影响。
Graphene nanosheets (GNPs)/polyethylene glycol (PEG) compound modifier was prepared by ultrasonic assisted dynamic dispersion device,and a series of polylactic acid(PLA)/GNPs/PEG composites were prepared by melt blending,then the samples were annealed at 120 ℃ under different times.The effects of compounding modifier GNPs/PEG and annealing on crystallization behavior of PLA were analyzed by wide angle X-ray diffractometry (WAXD) and polarized light microscopy (POM).The results shown that the introduction of GNPs/PEG did not change the crystal form of PLA,and with increasing of annealing time,the perfect degree of pure PLA crystals was further improved.Meanwhile,after annealing 30min,the crystals of PLA/GNPs/PEG were perfected,while the further extension of annealing time had almost no effect on the crystal.
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