Increased hydrophilicity of lignin-derivable vs. bisphenol-based polysulfones for potential water filtration applications.

The functionality inherent in lignin-derivable aromatics ( e.g. , polar methoxy groups) can provide a potential opportunity to improve the hydrophilicity of polysulfones (PSfs) without the need for the additional processing steps and harsh reagents/conditions that are typically used in conventional PSf modifications. As determined herein, lignin-derivable PSfs without any post-polymerization modification exhibited higher hydrophilicity than comparable petroleum-based PSfs (commercial/laboratory-synthesized) and also demonstrated similar hydrophilicity to functionalized BPA-PSfs reported in the literature. Importantly, the lignin-derivable PSfs displayed improved thermal properties relative to functionalized BPA-PSfs in the literature, and the thermal properties of these bio-derivable PSfs were close to those of common non-functionalized PSfs. In particular, the glass transition temperature ( T g ) and degradation temperature of 5% weight loss ( T d5% ) of lignin-derivable PSfs ( T g ∼165-170 °C, T d5% ∼400-425 °C) were significantly higher than those of typical functionalized BPA-PSfs in the literature ( T g ∼110-160 °C, T d5% ∼240-260 °C) and close to those of unmodified, commercial/laboratory-synthesized BPA-/bisphenol F-PSfs ( T g ∼180-185 °C, T d5% ∼420-510 °C).