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Mechanoluminescent Imaging of Osmotic Stress-Induced Damage in a Glassy Polymer Network.

ABSTRACT: A chemiluminescent mechanophore, bis(adamantyl-1,2-dioxetane), is used to investigate the covalent bond scission resulting from the sorption of chloroform by glassy poly(methyl methacrylate) (PMMA) networks. Bis(adamantyl)-1,2-dioxetane units incorporated as cross-linkers underwent mechanoluminescent scission, demonstrating that solvent ingress caused covalent bond scission. At higher cross-linking densities, the light emission took the form of hundreds of discrete bursts, widely varying in intensity, with each burst composed of 10⁷-10⁹ photons. Camera imaging indicated a relatively slow propagation of bursts through the material and permitted analysis of the spatial correlation between the discrete bond-breaking events. The implications of these observations for the mechanism of sorption and fracture are discussed.

SUBMITTER: Clough JM

PROVIDER: S-EPMC5352978 | biostudies-literature | 2017 Mar

REPOSITORIES: biostudies-literature

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Mechanoluminescent Imaging of Osmotic Stress-Induced Damage in a Glassy Polymer Network.

Clough Jess M JM van der Gucht Jasper J Sijbesma Rint P RP

Macromolecules 20170302 5

A chemiluminescent mechanophore, bis(adamantyl-1,2-dioxetane), is used to investigate the covalent bond scission resulting from the sorption of chloroform by glassy poly(methyl methacrylate) (PMMA) networks. Bis(adamantyl)-1,2-dioxetane units incorporated as cross-linkers underwent mechanoluminescent scission, demonstrating that solvent ingress caused covalent bond scission. At higher cross-linking densities, the light emission took the form of hundreds of discrete bursts, widely varying in inte ...[more]

PMID: 28316344

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Dataset Information

Mechanoluminescent Imaging of Osmotic Stress-Induced Damage in a Glassy Polymer Network.

Publications

Mechanoluminescent Imaging of Osmotic Stress-Induced Damage in a Glassy Polymer Network.

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