Towards Soft and Tough Polymer Networks through Controlled Gelation

Reversible deactivation radical polymerizations (RDRPs) revolutionized polymer science by enabling the synthesis of linear polymers with narrow dispersity and well-defined molecular weight. However, their impact over the kinetics of gelation and the structure-property relationships of polymer networks remains less explored.

In this talk, we will discuss the influence of RDRPs over the gelation, architecture, and mechanical properties of polymer networks. we will consider a series of rubbery poly(ethyl acrylate) networks (i) synthesized at varying rates of gelation, (ii) labeled with fluorogenic mechanophores, and (iii) exhibiting similar elastic modulus and swelling ratio. By interpenetrating this series within a poly(ethyl acrylate) matrix network and examining its mechanical properties in uniaxial tension and single-edge notch crack propagation, we will demonstrate how RDRPs offer control over the interplay between elasticity and fracture toughness in polymer networks. Confocal microscopy of the fracture surfaces will further highlight that this control stems from the impact of RDRPs on the efficiency of the damage delocalization mechanism ahead of cracks. Overall, these results aid in the design of soft and tough polymer networks for emerging and more stringent applications.