酚醛树脂共聚改性竹纤维复合材料的制备及其碳化行为

Preparation and Carbonization Behavior of Bamboo Fiber Modified by Copolymerized Phenolic Resin

用超声浸渍和热处理法制备酚醛树脂共聚改性竹纤维复合材料(PR-BF),研究了PR-BF的碳化性能及其机理。结果表明,在超声及热处理条件下,竹纤维(BF)具有很好的吸胶性能;红外光谱分析结果表明,酚醛树脂(PR)通过共聚反应接枝到竹纤维表面。碳化实验结果表明,与BF相比,PR-BF的热稳定性显著提高,25%PR-BF在900℃碳化后残碳率达到37.75%。用红外光谱法探讨了PR改性BF的碳化机理。结果表明,PR-BF发生热解的同时,BF还与PR通过进一步的共聚反应形成了新的苯环取代结构,使PR-BF表现出比BF高得多的热稳定性和残碳率。SEM结果表明,PR-BF碳化后出现纳米级纤维状粉体。

Copolymerized phenolic resin modified bamboo fiber composites(PR-BF) were prepared by a two step process i.e.firstly the bamboo fiber was immersed in an ultrasound irradiated bath of proper water solution of copolymerized phenolic resin and then undergone a heat treatment.The PR-BF composite was characterized by FTIR and its thermal property was examined by means of TG and DTG.The results show that bamboo fiber had excellent absorbability of phenolic resin; the phenolic resin is grafted on to bamboo fiber by copolymerization reaction; the thermal stability of the PR-BF composite increased dramatically with the increasing PR solid content in the solution; and the carbon residue of PR- BF reached a climax of 37.75% for the carburization at 900℃.From the FTIR analysis results it follows that in company with the thermal decomposition of PR-BF,a novel substitution product of benzene might form due to the copolymerization of BF with PR,which results in better thermal stability for PR-BF rather than the merely BF,and better resistance to elevated temperature rather than of the merely phenolic resin.Besides,after carburization the formed fiber-like nano-powders were good dispersed in PR-BF composite.