摘要
为了解自然紫外光老化对木塑复合材料(WPC)再加工的影响,即木粉增强聚丙烯(PP)复合材料。与纯PP相比,研究了两种木粉质量分数(10%和30%)。将注入的样品进行长期自然暴露,然后进行一次完整的再加工周期(研磨再注射)。光学显微镜观察了表面的视觉变化。为了了解材料的物理降解,通过拉伸和夏比冲击试验测量了材料的力学性能。微分扫描量热法(结晶率)、流变试验(黏度)、尺寸排除色谱测试(平均分子量)和红外光谱分析(化学结构),对微结构演变进行了评估。在再处理后恢复了机械性能,并强调了再生现象。这是由于在没有重组或交联机制的情况下,将退化链的混合和稀释转化为材料。最后,对同一样品进行的人工紫外风化进行了比较,并在前人的研究中进行了研究。
In order to identify and understand the effect of one-year natural UV weathering on the reprocessing performance of wood-plastic composite(WPC),i.e.a wood flour reinforced polypropylene(PP)composite,compared with pure PP,two types of wood flour reinforced polypropylene(PP)composites with different wood powder contents(10%and 30%(w/w))were studied.The injected samples were exposed to nature for a long time,and then the whole reprocessing cycle(grinding and reinjection)was conducted.The optical microscopy was used to observe the visual aspect evolution of the surface.In order to understand the physical degradation of the material,the mechanical properties of the material were measured by tensile and Charpy impact tests.The assessment of the microstructural evolution was performed by differential scanning calorimetry(crystallinity ratio),rheological tests(viscosity),size exclusion chromatography tests(average molecular weights)and infrared spectroscopy analysis(chemical structure).The microstructure evolution was evaluated by the differential scanning calorimetry(crystallization rate),rheological test(viscosity),the chromatographic test(average molecular weight)and infrared spectroscopic analysis(chemical structure).A"regeneration"phenomenon was highlighted as mechanical properties were recovered after reprocessing.This was due to the mixing and the dilution of the degraded chains into the material as no recombination or crosslinking mechanism was detected.Finally,the artificial ultraviolet weathering of the same sample was compared and studied.
作者
李良钊
刘毓海
LI Liang-zhao;LIU Yu-hai(College of Chemistry and Environmental Engineering,Hanshan Normal University,Chaozhou 521041,China;School of Chemistry and Molecular Engineering,Peking University,Beijng 100871,China)
出处
《当代化工》
CAS
2020年第12期2712-2717,共6页
Contemporary Chemical Industry
基金
广东省教育厅创新强校项目2018KTSCX141
潮州科技项目2018GY47韩山师范学院博士启动项目QD20180108支持和资助
关键词
聚丙烯
木粉
复合材料
再加工
天然紫外线风化
Polypropylene
Wood flour
Composites
Reprocessing
Natural UV weathering
