Fernando Sarah, Gunasekara Chamila, Shahpasandi Amin, Nguyen Kate, Sofi Massoud, Setunge Sujeeva, Mendis Priyan, Rahman Md Tareq
School of Engineering, RMIT University, Melbourne, VIC 3000, Australia.
Department of Infrastructure Engineering, University of Melbourne, Melbourne, VIC 3000, Australia.
Polymers (Basel). 2023 Jan 19;15(3):520. doi: 10.3390/polym15030520.
This review presents the research conducted to date in the field of cement-based composites reinforced with waste paper-based cellulose fibres, focusing on their composition, mechanical properties, and durability characteristics. The literature demonstrates that the properties of raw material (depending on their own chemical composition) significantly influence the formation of the cement composite binders. When considering fresh properties, the presence of silica and magnesium compounds generally lead to favourable effects on the setting of the cement composite when combined with waste paper cellulose fibre. Reduction in density values, i.e., approximately 25%, was observed with the inclusion of waste paper fibres from 20 to 80% in cement composites. The homogeneous dispersion of fibres in the matrix is one of the crucial factors to achieve in order to develop composites with well-balanced mechanical properties incorporating waste paper cellulose fibres. Hence, dispersion of fibres can be improved by increasing water quantity corresponding to the optimal value, which was a water/cement ratio of 0.64 leading to optimum strength properties of the composite. Even though the effect of fibre dispersion in the matrix improves with the addition of water, higher porosity and voids govern the strength properties beyond an optimum water-to-cement ratio. Higher porosity leads to an increase in the water absorption and a lowering of the thermal conductivity properties with the addition of paper fibre in cement binders. Paper fibre absorbs a high amount of water leading to higher water absorption. This phenomenon is related to the hydrophilic nature of cellulosic fibres absorbing some volume of water due to their microporous structure.
本综述介绍了迄今为止在废纸基纤维素纤维增强水泥基复合材料领域所开展的研究,重点关注其组成、力学性能和耐久性特征。文献表明,原材料的性能(取决于其自身的化学成分)会显著影响水泥复合粘结剂的形成。在考虑新拌性能时,二氧化硅和镁化合物的存在与废纸纤维素纤维结合时,通常会对水泥复合材料的凝结产生有利影响。在水泥复合材料中加入20%至80%的废纸纤维时,观察到密度值降低了约25%。纤维在基体中的均匀分散是制备具有良好力学性能的废纸纤维素纤维增强复合材料的关键因素之一。因此,可以通过将水量增加到对应于最佳值来改善纤维分散,最佳水灰比为0.64时可使复合材料具有最佳强度性能。尽管随着水的添加,纤维在基体中的分散效果会得到改善,但超过最佳水灰比后,更高的孔隙率和空隙会影响强度性能。在水泥粘结剂中添加纸纤维时,更高的孔隙率会导致吸水率增加以及热导率性能降低。纸纤维吸收大量水分,导致吸水率升高。这种现象与纤维素纤维因其微孔结构吸收一定体积水分的亲水性有关。