Sustainable compressed biocomposite: Review on development and novel approaches
Akash Gondaliya, Niloofar Alipoormazandarani, Maya Kleiman, E. Johan Foster
Abstract
The production of sustainable compressed biocomposites has gained significant attention due to its biodegradable and cost-effective properties. This review critically discusses the different pathways to design high mechanical strength compressed biocomposites, with potential applications as load-bearing construction material, thermoplastic, UV-block packaging, film, coating, etc. The process of densification provides the wood with a greater mechanical strength dimensional stability including enhancement in abrasion resistance, hardness, compared to the untreated wood. The effect of densification conditions i.e., pressure, time, temperature, cold/hot-pressing on the mechanical stability of final compressed biocomposite is summarized herein. To employ multifunctional properties and broaden the application of wood-based composites a pretreatment is required such as delignification or functionalization. Delignification helps in achieving wood porosity by removing the biopolymer lignin partially/completely from the wood leaving the 3-dimensional cellulose fibers framework intact for enhancing the densification process. Whereas functionalization or post treatment is applied to produce functional densified biocomposites with improved mechanical properties to be used as frost/water resistant, flame retardant, magnetic, or even to replace single use plastics in wearable medical application. This review paper presents an overview of the current pretreatment methods, functionalization and densification techniques used for converting wood into advanced biocomposite as well as it highlights the current gaps in the process and possible future opportunities to make the process of densification sustainable and industrially viable.