Bio-Based Polymer Membranes Recyclable via Dynamic Crosslinking for Sustainable Water Purification

https://doi.org/10.5281/zenodo.18096668

Abstract

Desalination and wastewater treatment have polymeric membranes at their core, and the traditional petro-based membranes are challenging to recycle and end-up as some of the unending examples of plastic waste materials. The paper presents a design framework of a bio-based membrane system constituted through dynamic covalent cross linking (covalent adaptable network, CANs) in order to facilitate the healing of defects as well as reprocessing as well as recycling of the closed loop in addition to preserving separation capabilities. Developing on the published idea of bio-based Vitrimer chemistry and close-loop re-useable membranes, we propose a reference structure: Cellulose- or chitosan-derived backbones, functionalized to form imine/boronic-ester exchange and optionally also associative vitrimer chemistry (e.g. transesterification) to allow thermal reprocessing. An informative model incorporates (i) performance relations (flux, rejection, pH-response), (ii) a low-tech fouling/cleaning life model, and (iii) an exemplary life-cycle comparison across end-of-life conditions. Findings indicate that modeled cradle-to-grave effects can be minimized by supporting dynamic crosslinking to facilitate reprocessing and closed-loop trips, and prevent the performance deterioration through defects. The framework offers an effective route toward the design of recyclable, bio-derived membranes to purify water sustainably and determines the main trade-offs in sustaining hydrolytic stability, choice of catalyst and processing window.