Preparation of Silica Composite Vitrimers via One‐Shot Transformation from Simple Polyesters

Abstract

AbstractTo solve the conventional problems of chemically cross‐linked polymers, the vitrimer concept has attracted great attention because the associative bond‐exchange nature in vitrimers provides sustainable functions. So far, various vitrimer designs have been reported using different polymer species with compatible bond exchange mechanisms. However, the biggest barrier for the practical application may be the elaborated functional group modification of the starting components and the limited availability of suitable monomers. As a much simpler preparation, recently, a one‐shot preparation of vitrimers from commodity polyesters with no special reactive functional groups by blending and heating with tetra‐functional epoxy molecules and base catalysts has been proposed. In this study, further one‐shot preparation of composite vitrimers with silica nanoparticles (SNPs) is developed. The effects of SNPs on the cross‐linking process and thermo/mechanical properties are first assessed, which reveals the formation of a bound rubber phase on the surfaces of the SNPs. The bound rubber phase also affects the bond exchange features of vitrimers, especially the distribution of relaxation time. Overall, the present facile preparation of composite vitrimers with enhanced mechanical properties could be a hint for practical application, whereas the knowledge on the unique relaxation behaviors of composite vitrimers should be beneficial in the fundamental sense.