Abstract
SynopsisIn order to achieve the cascade-type fl ow of lignocellulosic components as functional materials in human life, a novel conversion system has been developed and a new type of structure-controllable lignin-based polymers (lignophenols) has originally been designed. The originally designed process includes the phase-separative reaction system composed of phenol derivatives and concentrated acid. Through this process, native lignins are converted quantitatively to a new type of ligninbased polymer (lignophenols) composed mainly of 1,1-bis(aryl)propane type units. The selective grafting of monomeric phenol derivatives to C1-positions of propane units leads to the formation of new phenylpropane units between grafted phenolic units and lignin propane units, resulting in a dramatic change of the original lignin functions. The characteristic units in lignophenols, 1,1-bis(aryl) propane-2-O-aryl ethers, can be used as switching devices for the structural control. The separated carbohydrates include water-soluble monomers, oligomers,and polymers. These are easily converted to valuable chemicals such as alcohols, lactic acid, furfural, xylitol, etc. In order to create sustainable human society without petroleum, aliphatic and aromatic types of industrial raw materials must be derived from biomaterials (lignocellulosics). A new sustainable industrial network initiated from forests is designed.
