利用三辊研磨仪二维化法分散制备部分纤维化纤维素增强聚丙烯

Two-dimensional Method for Dispersion of Partially-Fibrillated Cellulose Reinforced Polypropylene via Three-roller-mill

从廉价的纸浆纤维中获得了部分原纤化纤维素(pFC),并通过三辊研磨仪加工制备了纤维增强复合材料。通过三辊研磨机加工的方法,利用强剪切力实现了纤维在疏水性基材聚丙烯(PP)中的良好分散,并通过Micro-CT图像和光学显微镜证实了分散性。在纤维含量为50%时,复合材料的拉伸强度和弹性模量的增加分别超过70%和140%。与纯PP相比,添加纤维素可将复合材料的热膨胀系数(CTE)从平均140×10-6 K-1降低到40×10-6 K-1。差示扫描量热法(DSC)测试结果显示,与PP相比该复合材料具有稍低的结晶温度和稍高的熔融温度。热重分析(TGA)结果表明,pFC和PP在复合物中为完全为两相,并且pFC的热稳定性低于PP。该研究展示一种以提高pFC增强PP复合材料中纤维的分散度的复合材料制备方法,同时该复合材料对于天然可再生材料的利用以及提高PP的工程应用价值提供了一条思路。

Partially fibrillated cellulose(pFC)was obtained from inexpensive pulp fiber,and fiber reinforced composites were prepared by three-roller-mill.Through the method of three-roller-mill,the dispersion of fiber in hydrophobic polypropylene(PP)substrate was achieved by using strong shear force,and the dispersion was proved by Micro-CT image and optical microscopic.When the content of fiber was 50%,the tensile strength and the elastic modulus of composites could increase more than 70%and 140%,respectively.The addition of cellulose could greatly decrease the coefficient of thermal expansion(CTE)of composites from average 140×10-6 K-1 to 40×10-6 K-1,comparing to the pure PP.The composite exhibits lower crystallization temperature and higher melting temperature comparing with PP through differential scanning calorimetry(DSC).Thermogravimetric analysis(TGA)results reveal that the pFC and PP are completely two-phase in composite,and thermal stability of pFC is lower than PP.The study shows a method which could be used to increase the fiber dispersion of pFC reinforced PP composite and provide an idea for the utilization of natural renewable materials and the improvement of the engineering application value of PP。