3种木塑复合材料的耐老化性能比较

木塑复合材料的老化性能直接关系其使用寿命和适用范围。使用稻壳、橡胶木锯末和橡胶籽壳分别与回收聚乙烯混合制备木塑复合材料。通过色差分析、红外光谱分析和差示扫描量热法(DSC),研究了3种木塑复合材料经紫外荧光老化后表面颜色、化学成分及结晶度的变化。结果表明,经2 000 h紫外荧光辐照后,处理B(锯末)ΔL和ΔE值为35和30,处理A(稻壳)为40和37,处理C(橡胶籽壳)为45和43;3种材料表面羰基浓度增大,表面氧化程度加深;紫外荧光辐照1 000 h后,处理B(锯末)结晶度由59.21上升到88.44,增加了49.37%;处理A(稻壳)结晶度由63.53上升到94.00,增加了47.96%;处理C(橡胶籽壳)结晶度由55.42上升到98.35,增加了77.46%。

Surface properties of biomass fiber/polyethylene composites with accelerated ultraviolet weathering

Aging properties of wood-plastic composites are directly related to their application. Currently，rubber wood and rubber seed shell are used in wood-plastic composites has not been reported. Changes on the surface of materials will be tested emphatically. Rice husk，rubber wood fiber，and rubber seed shell were each mixed with high-density polyethylene（HDPE） to make wood-plastic composites. Change in surface color，chemical composition, and degree of crystallinity for the three different materials subjected to ultraviolet（UV）weathering were monitored using color analysis, Fourier transform infrared spectroscopy（FTIR）and differential scanning calorimetry（DSC）. Results showed that after 2 000 h of aging，the ΔL and ΔE for rubber wood fiber was 35 and 30，for husks was 40 and 37，and for rubber seed shell was 45 and 43，respectively. Also，the concentration of carbonyl groups on the surface of the three materials increased，and the degree of oxidation was enhanced. After aging 1 000 h，crystallinity of the rubber wood fiber treatment increased from 88.44 to 59.21（49.37%）；for the husks treatment it increased from 94.00 to 63.53（47.96%）；and for the rubber seed shell treatment it increased from 55.42 to 98.35（77.46%）.［Ch，4 fig. 1 tab. 13 ref.］