ESR evidence of indirect main-chain scissions in poly(methyl methacrylate)

✍ Scribed by J. Sohma; M. Tabata

• Publisher: Elsevier Science
• Year: 1980
• Tongue: English
• Weight: 143 KB
• Volume: 16
• Category: Article
• ISSN: 0014-3057
• DOI: 10.1016/0014-3057(80)90092-0

✦ Synopsis

It was found that free radicals of poly(methyl methacrylate) (PMMA) were formed by addition of the spin trapping agent, 2,6,-di-chloro-nitrosobenzene (DCNB), to a PMMA-benzene solution. This PMMA radical was detected by the spin adduct with DCNB. It was identified as a chain scission radical CH3 H

by the analysis of the ESR spectrum and experiments using samples of PMMA deuterated either in the -,-methyl or in the ester methyl group. Since DCNB is known to abstract hydrogen from other molecules, the main chain scission of PMMA caused by the action of DCNB is an indirect process resulting from a fl-scission of the PMMA radical after a methylene hydrogen has been abstracted.