Lignin molecular design to transform green manufacturing

Abstract

<h2>Summary</h2> Lignin is the most abundant phenolic biopolymer on earth, representing an abundant feedstock for green manufacturing. Nevertheless, the diverse chemical linkages, heterogeneous functional groups, variable molecular weights, and amphiphilic structures all prevent the synthesis of fungible materials from lignin, leaving it as a predominantly low-value resource. On the basis of structure-property relationship, we synergistically overcome these challenges by chemical design of a type of lignin, high-molecular weight esterified linkage lignin (HiMWELL), with more uniform esterified linkages, larger molecular weight, and much lower OH group content via interunit substucture replacement. HiMWELL transforms lignin into a precursor for manufacturing renewable materials with drastically improved properties and functionality. The HiMWELL-based carbon fiber achieved a record tensile strength and better mechanical properties than the control polyacrylonitrile carbon fiber. HiMWELL also uniquely improved mechanical properties of the recyclable polymer blends and achieved UV-shading effects.