Depolymerizable and Reprocessable Self-Immolative Viscoelastomer

Abstract

The growing use of elastomers has driven strong interest in sustainable end-of-life strategies and smart materials for advanced technologies such as wearable devices. To date, most degradable elastomers undergo fragmentation by gradual random backbone cleavage and lack on-demand degradability. Self-immolative polymers offer end-to-end depolymerization in response to end-cap or backbone cleavage, with the ability to modulate the triggering stimulus by tuning the end-cap. In this paper, we describe a viscoelastic poly(ethyl glyoxylate) (PEtG) network containing carbamates capable of hydrogen bonding. These carbamates were introduced during chain extension of PEtG with two aroyl azide end-caps using six-carbon and disulfide-containing diol linkers. Different molar masses were investigated for the chain-extended polymers, with the intermediate and longer chains providing enhanced elasticity and Young’s moduli of 0.1–1.5 MPa. The materials could be completely degraded by acid, while chain segmentation was achieved by disulfide reduction. In addition, the viscoelastomers could be reprocessed by dissolution or heating.