Sustainable recycling of the biodegradable polyester poly(butylene succinate) via selective catalytic hydrolysis and repolymerization

The recycling of poly(butylene succinate) (PBS) plastic aligns with the principles of sustainable development and the circular economy. However, existing recycling systems often lack environmental friendliness and involve complex product separation operations. In this study, we developed a new recycling system based on succinic acid, a constituent monomer of PBS, as the catalyst and water as the solvent to hydrolyze PBS into different products, including oligomers, monomers, and tetrahydrofuran. These products (monomers or oligomers) were then repolymerized without requiring any separation steps by adding tetrabutyl titanate as the catalyst and 1,4-butanediol. The resynthesized PBS had similar mechanical and thermal properties to those synthesized from commercial monomers. In addition, the selective hydrolysis of PBS in mixed plastics was achieved by adjusting the reaction conditions. The process demonstrated here could inspire new recycling strategies for plastic wastes.