Plant fiber-reinforced green composite: A review on surface modification, properties, fabrications and applications

Abstract

Plastic pollution has become a persistent challenge globally. The extensive production of disposable plastics overwhelms the world's ability to cope with. These non-biodegradable plastics accumulating in landfills, rivers, and seas cause severe damage to wildlife and the environment. The utilization of biopolymer is a possible alternative to petroleum-based plastics. Polybutylene succinate (PBS), polyhydroxyalkanoates (PHA), polylactic acid (PLA), poly(ε-caprolactone) (PCL), cellulose, chitin, and thermoplastic starch are mostly used biopolymers with promising properties. There are challenges too. Properties including brittleness, low thermal stability, low strength, and poor chemical barrier properties are the challenges to replacing plastics material. Reinforcing natural fibers as an alternative to non-biodegradable synthetic fiber with biopolymer matrices improves the properties of the material significantly. Flax, kenaf, jute, ramie, and hemp are a few agro-based fibers that are generally reinforced with biopolymer matrices. These composites are known as green composites. In order to create an interfacial bond between hydrophilic fiber and hydrophobic biopolymer surface modification of natural fiber is needed. There are many physical and chemical methods of surface medication which enhance roughness, wettability as well as hydrophilicity, lowers moisture absorption, improve the interfacial bond, and also enhance the tensile properties of natural fiber. The review is on the classification of biopolymers, natural fibers and their properties as well as the surface modification techniques for plant fibers. Moreover, the fabrication, mechanical and chemical properties including biodegradation of different green composites and the application of green composites, are also discussed here.