茶生物质/聚丙烯复合材料的制备与性能研究

为高值化利用茶产业剩余物资源,以废弃茶生物质(Tea biomass,TB)为填料,聚丙烯(Polypropylene,PP)为基体,采用密炼-注塑工艺制备了TB/PP复合材料,考察了茶生物质填料种类、处理方式及其添加量对复合材料结构、形态及性能的影响。实验结果显示,以茶树枝为生物质填料制备的复合材料力学性能最佳,茶梗次之,茶叶最差;茶梗填料经水煮和马来酸酐接枝聚丙烯增容处理后,复合材料的拉伸强度、弯曲强度、拉伸模量及弯曲模量分别提高了23.4%、9.0%、16.9%和13.9%。SEM图片显示茶梗填料与基体界面相容性提高。随茶梗填料用量的增加,复合材料的拉伸模量、弯曲模量逐渐增大,而拉伸强度及断裂伸长率缓慢下降,吸水率增加,热性能得到改善。当TS添加量为30%(质量分数)时,复合材料的拉伸强度比PP减小7.3%,但弯曲强度、弯曲模量及拉伸模量则分别提高11%、86.1%和54.7%。浸水80h后吸水率为0.89%。

Preparation and Properties of Wasted Tea Biomass/Polypropylene Composites

Aimed to make high-valued use of the wasted tea biomass, tea biofiller/polypropylene composites were manufactured by internal mixing and injection molding machine. The effects of filler species, treatments and contents on the structure, morphology and properties were studied. The results showed that the composites made with tea fillers from the tree branch showed the best mechanical properties, followed by tea stalk and then tea leaf. The tea stalk treated with boiling water and MAPP couping agent showed an improvement of 23.4% in tensile strength, 9.0% in bending strength, 16.9% in tensile modulus, and 13.9% in flexural modulus, respectively. Scanning electron microscope indicated that the complex treatment enhanced interfacial adhesion between tea stalk and PP. The stiffness of the TS/PP composites was significantly improved with the increase in TS content, while the strength and toughness slowly decreased. The thermal properties were improved with the addition of TS. When mass fraction of TS was 30%, the tensile strength was reduced by 7.3%, but the bending strength, modulus and tensile modulus was improved by 11%, 86.1% and 54.7%, respectively, compared to PP. The water adsorption was 0.89% when the composites were soaked in water for 80 h.