Recently, researchers and scientists are trying to overcome the environmental burden by using biocomposites in engineering applications as far as possible. The main source of biocomposites is cellulosic fibres which is a class of natural fibres. Instead of many advantages of cellulosic fibres, they and their polymer composites suffer from some limitations as well. The environmental conditions are one of the most important issues to degradation behavior of the cellulosic fibres polymer composites (CFPCs). Among the environmental conditions, water absorption is an important ground to degradation in the mechanical performance of the CFPCs, which resists them to be used in outdoor applications. Several studies have been presented on water absorption characteristics of cellulosic fibres and its polymer-based biocomposites. Further, the consequence of water uptake on the mechanical performance of biocomposites was also reported in many studies. In most of the cases, a negative effect of water absorption was observed, whereas in a few cases a positive effect was also seen. In the present study, mechanics and kinetics of water absorption for CFPCs are discussed. Further, a detailed literature review on water absorption of cellulosic fibres and their different types of polymer-based biocomposites has also been carried out. Furthermore, studies reported on the effect of water absorption on the mechanical properties were also systematically presented. Moreover, all the possible remedies to lower the water absorption capacity were also discussed in the present review paper.
The positive effect of water on photo-induced step transfer-addition & radical-termination (START) polymerization
