Plastics are critically important in modern society, but improper disposal has created significant environmental issues. One approach to decrease the environmental burden is to make plastics more degradable. As such, renewable biopolymers with nature’s recycling stamp are being investigated as potential feedstocks for these applications. Kraft lignin from the pulp and paper industry is an industrially available polymer that has been previously demonstrated in commercial applications in melt blown plastic blends. In an attempt to elucidate characteristics of the lignin that can enhance the performance when blended with polybutylene adipate terephthalate (PBAT), we studied nine different lignins with various functionality.  These lignins included unmodified softwood kraft lignin, hydoxyethylated and esterified derivatives, along with their acetone fractionated counterparts. Characteristics of the lignin were fully evaluated using thermal analysis, gel permeation chromatography, and spectroscopy and these samples were subsequently melt blended at different levels with PBAT. Injection molded samples were tested for their tensile mechanical properties. Dependent upon the lignin sample and loading level, blends either had a significant enhancement of all mechanical properties or significant decrease in strength and elongation at break. Samples were also composted revealing surprising performance of the PBAT-lignin material under simulated industrial composting conditions.

How much does kraft lignin derivatization help in enhancing performance of polymer blends?

ACS Spring 2022

The official archive and repository for all ACS Meetings & Expositions abstracts and select posters or presentations.