不同长度玻纤增强聚丙烯热氧老化性能  

Thermal oxygen aging properties of polypropylene enhanced by different lengths glass fiber

作　　者：林明华 黄鑫 郭建兵 王华 LIN Minghua;HUANG Xin;GUO Jianbing;WANG Hua(Kangmingyuan(Guizhou)Technology Development Co.,Ltd.,Anshun 561100,China;Guizhou Institute of Materials Industry Technology,Guiyang 550014,China)

机构地区：[1]康命源(贵州)科技发展有限公司,贵州安顺561100 [2]贵州省材料产业技术研究院,贵阳550014

出　　处：《工程塑料应用》2024年第8期148-153,共6页Engineering Plastics Application

基　　金：国家自然科学基金项目(52263007);贵州省科技计划项目(黔科合平台人才-ZZSG[2024]015,黔科合中引地项目[2024]020)。

摘　　要：为研究不同长度纤维复配对聚丙烯(PP)复合材料热氧老化性能的影响,采用熔融浸渍法制备了长玻璃纤维(LGF)增强PP复合材料(PP/LGF),在120℃的热氧环境下持续老化40 d后,利用旋转流变仪、扫描电子显微镜(SEM)等对老化样品进行观察表征,对比不同长度复配的LGF在热氧老化下对PP复合材料力学、结晶及流变等性能的作用,探讨LGF长度复配对PP复合材料老化性能的影响机理。结果表明,经40 d的老化后,PP复合材料拉伸强度平均下降仅为2.39%,弯曲强度上升了0.79%,而冲击强度保持率达到87.0%以上。老化前后,纤维复配PP样品均有较高的结晶度且老化后进一步提高到49.12%。老化后纤维复配的PP样品出现了明显的剪切应力下降。另外,通过SEM观察到,老化前后,复合材料界面微观形貌变化不明显,但GF质均长度较低的样品与PP基体结合较好。研究表明,热氧老化使得GF增强PP复合材料整体呈变硬变脆的趋势下,纤维长度复配对这一趋势有较好的抑制作用,并提高了材料冲击强度的稳定性;不同长度纤维共同作用有利于提高PP复合材料在老化过程中的结晶度并降低剪切应力。In order to study the effect of different lengths fiber on the thermo-oxygen aging properties of polypropylene(PP)composites,PP composites reinforced with long glass fiber(PP/LGF)were prepared by melt impregnation method.After continuous aging for 40 days at 120℃,the aging samples were observed and characterized by rotating rheometer and scanning electron microscope.The effects of different length composite glass fibers on the mechanical,crystalline and rheological properties of PP composites under thermal oxygen aging were compared,and the mechanism of the effects of long and short fiber composite on the aging properties of PP were discussed.The results show that after 40 days of aging,the average tensile strength decrease by 2.39%,the bending strength increase by 0.79%,and the impact strength retention rate reach more than 87.0%.Before and after aging,the crystallinity of fiber composite samples is higher and increase to 49.12%after aging.After aging,the shear stress of PP composite samples decrease obviously.In addition,it was observed by SEM that the change of the interface morphology was not obvious before and after aging,but the samples with lower average length of glass fiber were better combined with PP matrix.The results show that under the trend of hardening and brittleness caused by thermal oxygen aging,the different length of fiber pairing has a better inhibition effect on this trend,and improves the stability of impact strength.The combination of different length of fibers can improve the crystallinity of PP composite and reduce the shear stress during aging.

关 键 词：玻璃纤维 复配 聚丙烯 热氧老化 力学性能 

分 类 号：TQ322.2[化学工程—合成树脂塑料工业]