Malenab Roy Alvin J, Ngo Janne Pauline S, Promentilla Michael Angelo B
Chemical Engineering Department, De La Salle University, Manila 0922, Philippines.
National Research Council of the Philippines, Taguig, Metro Manila 1631, Philippines.
Materials (Basel). 2017 May 25;10(6):579. doi: 10.3390/ma10060579.
The use of natural fibers in reinforced composites to produce eco-friendly materials is gaining more attention due to their attractive features such as low cost, low density and good mechanical properties, among others. This work thus investigates the potential of waste abaca (Manila hemp) fiber as reinforcing agent in an inorganic aluminosilicate material known as geopolymer. In this study, the waste fibers were subjected to different chemical treatments to modify the surface characteristics and to improve the adhesion with the fly ash-based geopolymer matrix. Definitive screening design of experiment was used to investigate the effect of successive chemical treatment of the fiber on its tensile strength considering the following factors: (1) NaOH pretreatment; (2) soaking time in aluminum salt solution; and (3) final pH of the slurry. The results show that the abaca fiber without alkali pretreatment, soaked for 12 h in Al₂(SO₄)₃ solution and adjusted to pH 6 exhibited the highest tensile strength among the treated fibers. Test results confirmed that the chemical treatment removes the lignin, pectin and hemicellulose, as well as makes the surface rougher with the deposition of aluminum compounds. This improves the interfacial bonding between geopolymer matrix and the abaca fiber, while the geopolymer protects the treated fiber from thermal degradation.
由于天然纤维具有低成本、低密度和良好机械性能等吸引人的特性，其在增强复合材料中用于生产环保材料正受到越来越多的关注。因此，本研究探讨了废弃蕉麻（马尼拉麻）纤维作为增强剂在一种名为地质聚合物的无机铝硅酸盐材料中的潜力。在本研究中，对废弃纤维进行了不同的化学处理，以改变其表面特性并改善与粉煤灰基地质聚合物基体的粘附性。考虑以下因素，采用实验的确定性筛选设计来研究纤维连续化学处理对其拉伸强度的影响：（1）氢氧化钠预处理；（2）在铝盐溶液中的浸泡时间；（3）浆料的最终pH值。结果表明，未经碱预处理、在Al₂(SO₄)₃溶液中浸泡12小时并调节至pH值6的蕉麻纤维在处理后的纤维中表现出最高的拉伸强度。测试结果证实，化学处理去除了木质素、果胶和半纤维素，同时铝化合物的沉积使表面更粗糙。这改善了地质聚合物基体与蕉麻纤维之间的界面结合，而地质聚合物则保护处理后的纤维免受热降解。
