High-performance vitrimers from commodity thermoplastics through dioxaborolane metathesis

TLDR

Polymers used in windmills, cars, and dental restoration must be processable, recyclable, and mechanically, thermally, and chemically robust, and vitrimers—networks that shuffle bonds via exchange reactions—offer a promising route to meet these demands. The study aims to produce vitrimers from commodity thermoplastics using fast, scalable dioxaborolane metathesis compatible with existing manufacturing equipment. Rapid, thermally robust dioxaborolane metathesis yields cross‑linked vitrimers from PMMA, polystyrene, and HDPE that can be repeatedly extruded or injection‑molded, exhibit superior chemical resistance and dimensional stability, and are applicable to polymers with C–C backbones.

Abstract

Windmills, cars, and dental restoration demand polymer materials and composites that are easy to process, assemble, and recycle while exhibiting outstanding mechanical, thermal, and chemical resistance. Vitrimers, which are polymer networks able to shuffle chemical bonds through exchange reactions, could address these demands if they were prepared from existing plastics and processed with fast production rates and current equipment. We report the metathesis of dioxaborolanes, which is rapid and thermally robust, and use it to prepare vitrimers from polymers as different as poly(methyl methacrylate), polystyrene, and high-density polyethylene that, although permanently cross-linked, can be processed multiple times by means of extrusion or injection molding. They show superior chemical resistance and dimensional stability and can be efficiently assembled. The strategy is applicable to polymers with backbones made of carbon-carbon single bonds.