中文摘要：

采用模压和热压两种成型方法制备高木材纤维含量的聚丙烯（PP）基木塑复合材料,研究不同工艺方法和木材纤维质量分数（50%-90%）对木塑复合材料吸水性、接触角、表面自由能以及力学性能的影响,并通过扫描电子显微镜对复合材料的层间断面形貌进行观察。结果表明,木材纤维质量分数的提高使复合材料表面润湿性增强,力学性能有所下降,储能模量降低,玻璃化转变温度提高。当木材纤维质量分数达到80%时,复合材料仍可保持较好的弹性模量和冲击韧性;24 h吸水厚度膨胀率小于15%,可在潮湿环境下使用;表面自由能极性分量与中密度纤维板相当。扫描电镜结果表明,木材纤维质量分数增加可使复合材料的界面结合减弱。采用模压工艺制备的复合板材密度较大,抗弯性能较好;热压工艺所制复合板材的润湿性和冲击强度均优于模压工艺,在贴面装饰方面具有潜在优势。

英文摘要：

Wood fiber reinforced polypropylene （WF/PP） composites were prepared through two processing methods of compression molding and hot pressing. The effects of wood fiber content （ 50%-90% ） and processing methods on WF/PP composite properties, such as moisture absorption, contact angles, surface energy and mechanical properties were evaluated, and the interlamination fracture surface of composites were observed with the scanning electron micro- scope （SEM）. The results showed that, with the increase in wood fiber content, the wettability of the WF/PP com- posites was improved, the mechanical properties were decreased, the storage modulus were reduced, and the glass transition temperature was increased. When wood fiber content reached 80%, the composites remained good flexural modulus and impact strength. The 24 h thickness swelling was lower than 15%, indicating that WF/PP composites could be used in humid environment. The surface energy polar components of WF/PP composites were comparable to that of medium density fiberboard. The results of SEM images showed that, with the increase in wood fiber content, the interface bonding of composites was weakened. Compared with the composites manufactured by hot pressing method, the composites made by compression molding method had higher density and better flexural modulus. However, the composites made by the hot pressing method showed better surface wettability and impact strength, indicating that the hot-pressed composite has advantage in terms of surface covering decoration.