Hybridizing a Dual-Cross Network and a Linear Glassy Polymer for Dynamic Contributions to High Mechanical Toughness Based on Phase-Separated Structures

Abstract

Bulk copolymerization of alkyl acrylate and cyclodextrin (CD) host monomers forms a single movable cross network (SC), in which the CD units act as movable cross-linkers. Moreover, the bulk copolymerization of the CD monomer and main chain monomer in the presence of SC results in dual-cross-network (DC) elastomers. DC elastomers result in good toughness (G f). Here, to improve G f and Young’s modulus (E), we hybridized DC elastomers with tertiary glassy polymers, which are called DCP elastomers. We prepared the DCP elastomers by photopolymerization of N,N-dimethyl­acrylamide (DMAA) and poly(2-methoxyethyl acrylate) (MEA) in the presence of DC. A DCP elastomer with a suitable weight percent (wt %) of the glassy polymer shows high G f (108.4 MJ m–3) and E (223.4 MPa) values. Dynamic mechanical analysis (DMA) and in situ small-angle X-ray scattering (SAXS) measurements under uniaxial stretching indicate multiple deformations based on phase-separated structures. We suggest that the phase-separated structures of DCP elastomers cause a large stress dissipation, which contributes to high toughness.

Enhancement of the mechanical properties of organic–inorganic hybrid elastomers by introducing movable and reversible crosslinks

“…41,42 We have succeeded in improving the compatibility and toughness characteristics by compositing immiscible polymers with movable crosslinks; in these systems, the main chain penetrates the CD cavity. 43–46 We hypothesize that if the organic polymer and PDMS can be crosslinked by movable crosslinks, each function will be combined and the mechanical properties will be improved. In this study, we propose the enhancement of the mechanical properties of a polymer blend with the topological and reversible crosslinking design between dissimilar polymers.…”