Synthetic polymer-lignin copolymers and blends

A review covers the potential of lignin as a chemical component for the synthesis of organic fibers, copolymers, and polyblends. The basic chemical units of phenylpropane in Lignin are bonded to form a complex matrix which comprised a variety of functional groups imparting high polarity to the Lignin macromolecule. The use of degraded lignins as raw materials for polymers is described along with lignin-based engineering plastics, adhesives, foams (e.g. polyurethane), and films, and the lignin--epoxy system. Applications of lignin in rubber compounding and resin formation as an extender, modifier, and reinforcing pigment are outlined. The advantages of lignin as non-toxic, renewable, commercially available, and lost cost material are partially offset by the limitation of the production techniques which could alter its macromolecular structure with a reduction in reactivity and an increase in inhomogeneity.