Lignin as Potent Industrial Biopolymer: An Introduction

Lignin is a complex biological molecule and well known as a second abundant biopolymer on the planet. It also produced as a by-product of lignocellulosic biomass, paper and pulp industry. It has not been well explored for industrial applications due to its poor solubility and complex molecular structure. Hence, since last two decades, lignin has gained the attention of researchers as a raw material for the synthesis of value-added products of commercial importance. However, the major part of the lignin derived from the pulp industry is being utilized as boiler fuel. The efficacy of lignin produced from lignocellulosic-based bio-ethanol industry to synthesize the renewable polymeric material is much higher as compared to the lignin obtained from pulp industry. These days lignin has also been exploited to synthesize various chemicals like esters, ethers, bio-adhesives, biolubricants, foams, nano-particles and nano-composites. The excessive production of lignin from paper or bio-ethanol industry has also appeared as critical environmental problem. The conversion of huge amount of lignin will not only help to solve the environmental threat but also boost the bio-economy of bio-ethanol and paper industry. In this chapter, we highlight the sources, extraction of lignin and its immense industrial importance.