Tandem Two-Component and Multicomponent Polymerization toward Ketene Dithioacetal-Containing Polymers with Tailored Degradability

Diversity-oriented polymerization is critical for the exploitation of new functional polymers and polymeric materials. Drawing inspiration from tandem polymerizations, herein, we introduce an unprecedented tandem two-component (or bimolecular) and multicomponent polymerization (TTMCP) to address the challenge of limited diversity of polymer structures in traditional step-growth polymerizations. Theoretically, a library of polymers with varying compositions can be synthesized from a finite set of monomers by carefully adjusting their feed ratios in the TTMCP. The key to success lies in the simultaneous and independent occurrence of the two-component polymerization of acetoacetate-dibromomethylbenzene and the multicomponent polymerization of acetoacetate-dibromomethylbenzene-CS2. After reaction optimization, 19 samples of high-molecular-weight polymers were prepared, with the TTMCP method allowing simultaneous manipulation of the structures of both the main chains and the side groups. Moreover, the introduction of ketene dithioacetal into the polymer backbone confers distinctive cysteamine-triggered degradation properties, with degradation kinetics being controlled by the percentage of ketene dithioacetal. Furthermore, TTMCP can be integrated with the interfacial polymerization technique to produce degradable polymeric films. This study provides a general strategy for the synthesis of new polymer libraries and is expected to stimulate further exploration of TTMCP in interdisciplinary research fields.