Nature of mechanoradical formation of substituted celluloses as studied by electron spin resonance.
Mechanically induced free radical (mechanoradical) formation of several substituted celluloses such as carboxylmethyl cellulose, chitin, and chitosan was studied based on electron-spin resonance (ESR) in comparison with those of plasma-induced radicals. Room temperature ESR spectra had multicomponent spectra and were different in pattern from each other. The mechanoradical concentration gradually decreased after reaching the maximum value in each substituted polysaccharide, accompanied by a decrease in molecular weight in the course of vibratory milling. One of the most intriguing facts is that the component radicals are all glucose-based radicals as in the case of plasma irradiation, although it is known that mechanoradicals are formed by 1,4-glucosidic bond cleavage of polysaccharides.
Sasai
Yasushi
Y
Laboratory of Pharmaceutical Physical Chemistry, Gifu Pharmaceutical University, Gifu, Japan.
Yamauchi
Yukinori
Y
Kondo
Shin-ichi
S
Kuzuya
Masayuki
M
D002482:Cellulose / Q000737:chemistry; D002686:Chitin / Q000031:analogs & derivatives* / Q000737:chemistry; D048271:Chitosan; D003198:Computer Simulation; D004578:Electron Spin Resonance Spectroscopy; D005609:Free Radicals / Q000032:analysis* / Q000528:radiation effects; D015394:Molecular Structure; D011134:Polysaccharides / Q000737:chemistry*
D005609:Free Radicals; D011134:Polysaccharides; D002686:Chitin; D002482:Cellulose; D048271:Chitosan