A Review on Natural Plant Fiber Epoxy and Polyester Composites - Coating and Performances

In the last two decades, there has been an incredible awareness on natural plant fiber composites due to their biodegradability, low weight, non-corrosiveness, and recyclability. Many studies have been attempted to improve the performance of the natural plant fiber composite since it has many applications in the engineering sectors. But the adaptation of natural plant fiber composite has some drawbacks such as water absorption, non-linearity in fiber dimensions, low interfacial adhesion between fiber-matrix, and less uniform strength of the fiber. Several studies have attempted to enhance the natural plant fiber composite properties by various fibers, matrix, fiber orientation, fiber treatment, fiber loading, fiber length, fillers, and other reinforcements. However, fiber's hydrophilic character is inevitable and influences the composite performance. To overcome the drawback, fiber coating is a felicitous technique. Few researchers have performed the fiber (Sisal, Jute, Flax, Ramie, Bamboo) coating to enhance the composite properties of tensile strength, flexural strength, impact strength, water resistance, viscoelastic behavior, and electrical conductivity. Considering the importance of fiber coating (Dip, Spray, Electroless), the present study summarizes the fiber coating types, coating materials, and their composite performance.