定向重组竹纤维素纤维/酚醛树脂复合材料的制备及其性能

Preparation and properties of directionally reconstituted bamboo cellulose fiber/phenolic resin composites

研究以毛竹为原料,首先通过不同程度的脱木素处理制备成块状的定向竹纤维素纤维,然后进行酚醛树脂浸渍,最后高温热压成定向重组竹纤维素纤维/酚醛树脂复合材料(DBSP)。SEM、FTIR、XRD等检测显示随着脱木素时间的增加,木素含量逐渐降低,纤维素结晶度逐渐增加,竹材细胞壁变薄,并逐步被分离成微米级的定向竹材纤维素纤维。同时,研究指出随着脱木素处理时间的增加,DBSP的力学性能被显著提高,吸水率、尺寸稳定性均得到明显的改善。其中,脱木素处理6 h后的竹纤维素纤维制备的DBSP表现出优异的综合性能,其拉伸强度和静曲强度分别达到254.3 MPa和176.8 MPa,24 h吸水率为5.83%,24 h吸水厚度和宽度膨胀率分别为2.28%和0.76%,因此,作为一种高性能的竹重组复合材料,可广泛应用于风力发电机叶片、汽车车身制造等领域。

Bamboo cellulose fiber was prepared via deligninfied treatment at different times, then was impregnated with phenolic resin, finally was fabricated into the directionally reconstituted bamboo cellulose fiber/phenolic resin composites(DBSP) under hot pressing. SEM, FTIR, and XRD tests indicate that with the increase of deligninfication time, the lignin content gradually decreases, the crystallinity of cellulose gradually increases, and the bamboo cell wall also becomes thinner, finally the bamboo cell wall is separated into micron-scale oriented bamboo cellulose fibers. Moreover, the performance tests display that the mechanical strength, water absorption and dimensional stability of DBSP are significantly improved with the increase of deligninfication time. Among them, DBSP(6 h) shows excellent comprehensive performance, in which the tensile strength and modulus of rapture are up to 254.3 MPa and 176.8 MPa, respectively;the water absorption of 24 h is decreased to 5.83%, and the absorbing water thickness and width expansion rate are 2.28% and 0.76%, respectively. Therefore, as a kind of high-performance bamboo orientation recombined composites, it could be widely used in wind tur-bine blades, automotive body and other fields.