Lignin-polymer systems and some applications

Lignin is a renewable, non-toxic, commercially available and low costing resource which has the potential of being utilized as a basic raw material for the chemical industry. In spite of many years of development effort however, this potential has not been fully realized. One of the many reasons for the difficulties encountered in the production of useful polymeric products is the fact that the technical processes by which lignin is obtained, alter its macromolecular structure in such a fashion as to reduce its reactivity. Recent developments of the macromolecular uses in lignin-polymer material systems have shown an increased awareness of the inherent limitations and potential of the structure of lignin. In this paper, the present state of knowledge regarding the chemical structure of lignin is briefly described, and some more current areas of application are reviewed; lignin graft copolymers, lignin-thermosetting polymer systems and lignin-elastomer systems.