In order to make full use of the by-products of the industrial production of coffee bean,the shell of the coffee bean wasused as the raw material. It was purified by series of chemical treatments to remove the lignin and hemicellulose,and theα-cellulose content of the resulting purified pulp was 83.7 ％. Then the sample was passed once through a grinder to extract the nanofibers (CNF),which presented a uniform diameter of approximately 15–30 nm. The CNFfilm was made using vacuumfiltra-tion and dry method, and then impregnation method was conducted to prepare acrylic resin/CNF compositefilm. After UV-curing, the compositefilm showed good transparency,with a light transmittance of 85.3 ％. The thermal expansion analysis shows that the thermal expansion coefficient of pure CNFfilm is very low (13.5×10–6/K);and that of the CNF/acrylic resin compositefilm can reach 23.8×10–6/K,which shows good dimensional stability. The results of the study can provide reference for the application of coffee shells in high value-addedfields.%为充分利用咖啡豆的工业生产副产物,以咖啡豆壳为原料,通过化学法脱去咖啡壳中所含的木质素和半纤维素,制得纯化纤维素;测得纯化纤维素的α-纤维素含量为83.7％.采用一次研磨法制得咖啡壳纳米纤维素(CNF),直径均匀分布在15～30 nm.所得CNF通过真空抽滤成膜干燥后,利用浸渍法将CNF膜与丙烯酸树脂复合,经紫外光固化后,测得复合膜的透光率高达85.3％.热膨胀性分析表明,纯CNF膜的热膨胀系数极低(13.5×10–6/K),丙烯酸树脂/CNF复合膜的热膨胀系数可达23.8×10–6/K,尺寸稳定性佳.研究结果可为咖啡壳在高附加值领域的应用提供参考.
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