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Investigation into the Direct Photolysis Process of Photo-Induced RAFT Polymerization by ESR Spin Trapping.

ABSTRACT: The direct photolysis of reversible addition fragmentation chain transfer (RAFT) agents under visible light was demonstrated by electron spin resonance (ESR) using 5,5-dimethyl-1-pyrroline N-oxide as a typical spin trap. The hyperfine coupling lines obtained by ESR spectroscopy showed the successful capture of the carbon-centered and the sulfur-centered radical. Photo-polymerization of vinyl acetate under different wavelengths was performed to verify the effects of wavelength on the process. The effect of the R group of RAFT agents on the photolysis was investigated by spin-trapping experiments using poly (butyl acrylate) and poly (vinyl acetate) as macroRAFT agents. The quantitative experiment showed the yield of photolysis of a xanthate to be only 0.023% under ? > 440 nm.

SUBMITTER: Li J

PROVIDER: S-EPMC6835659 | biostudies-literature | 2019 Oct

REPOSITORIES: biostudies-literature

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Investigation into the Direct Photolysis Process of Photo-Induced RAFT Polymerization by ESR Spin Trapping.

Li Jiajia J Zhang Mengmeng M Zhu Jian J Zhu Xiulin X

Polymers 20191021 10

The direct photolysis of reversible addition fragmentation chain transfer (RAFT) agents under visible light was demonstrated by electron spin resonance (ESR) using 5,5-dimethyl-1-pyrroline <i>N</i>-oxide as a typical spin trap. The hyperfine coupling lines obtained by ESR spectroscopy showed the successful capture of the carbon-centered and the sulfur-centered radical. Photo-polymerization of vinyl acetate under different wavelengths was performed to verify the effects of wavelength on the proce ...[more]

PMID: 31640166

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