A cutting-edge review emphasizing the key approaches for chemical transformation of lignocellulosic fibers for viable engineering composites

Composite materials play a crucial role in the expanding high-tech world by enabling lighter, stronger, and more durable products while offering enhanced design flexibility and performance characteristics. They are very important materials for aerospace, automobile, marine, electronic and telecommunications, health care etc. Composite materials pose environmental concerns like resource intensity, raw material sourcing, waste generation, high energy consumption, use of toxic chemicals during manufacturing, thus require introduction of bio based materials during manufacturing to reduce environmental carbon footprints. Replacing fossil fuels with agro-wastes such as lignocellulosic fibers (LCFs) in making composites supports sustainable development goals by mitigating climate change, reducing waste, improving resource efficiency, and promoting environmental stewardship. It represents a significant step towards building a more sustainable and resilient economy. However, due to the incompatibility between hydrophilic nature of the LCFs and hydrophobic thermoplastics the composites damage and issues like moisture absorption, dimensional instability and degradation of mechanical properties arise. One of the ways to deal with the incompatibility is surface modification of the LCFs. Chemical modification increases the hydrophobicity of LCFs hence results in better reinforcing for fabricating defect free composite materials. This article is a comprehensive review of LCFs-reinforced composites based on diverse surface modification techniques with varied chemicals that improve the requisite properties of the composites.