Lignin is one of the major by-products of the paper and the biofuel industries, which might be considered to be one of the most complex and hydrophobic polymers. The role of lignin in the structure of plants is substantial. Although many functional properties of lignin offer great potential for coatings, adhesives, and biocomposites, the complexity and hydrophobicity of lignin has so far limited its economically viable use. With the advancement of susceptibility of lignin toward wide applications through overcoming difficulties from above, surface modification of polyethylene oxide has now been successfully proved. Due to known hydrophilicity, flexibility, and water solubility, polyethylene oxide (PEO) is a good modifier for the improvement of incorporative capability of lignin in diverse formulations. Apart from characteristic analysis of PEO and structural aspects of lignin, the chapter has many grafting techniques for the modification of PEO onto lignin esterification, graft copolymerization, and even physical absorption. The changes were verified and evaluated by employing several sophisticated characterization techniques that included Fourier transform infrared spectroscopy (FTIR), nuclear magnetic resonance (NMR), scanning electron microscopy (SEM), and thermogravimetric analysis (TGA). Modified lignin is hydrophilic, dispersible, thermally stable, and has value for environmental adhesives, coatings, mechanically reinforced and water-resistant biocomposites, and biocompatible drug delivery systems. Development suggests the use of employment as a high-performance, sustainable material in the biomedical, automotive, packaging, and construction industries. This modification strategy provides new momentum toward using lignin and encourages the wider adoption of renewable, environmentally friendly materials for potential applications in the future – highly relevant given the growing demand for environmentally responsible operations in industries.
