Infrared spectroscopy of graft polymers separated from graft copolymers of wool and silk with methyl methacrylate

Abstract

SynopsisThe IIC1-or papain-decomposition residues obtained from rednced wool fibers grafted wit,h 1 .5-3.0yo methyl methacrylate were extractively fractionated successively wit,h cold acetone, hot acetone, and benzene. Each fraction was examined by infrared spectroscopy. Generally, the 715 cm-' spectral band considered to he due to YC-S-C was found iri the hot acetone-soluble fraction. It was concluded that the thiol groups on wool keratin provide the main sites of grafting, as might he expected. A similar result was obtained for grafted silk fibroin fibers, the methionine residue being presumed to he related to some of the grafting sites at least. Furthermore, a sort of stereoregularity was observed in some of the graft polymer fractions, isotactic-rich material being obtained in the case of silk fibers. In the range of very low grafting, a stereoregulating effect on the structure of the polymer formed within fibers appears to be present in relation to the grafting or adsorption sites of monomers and the fine structure of fibers.

Polymer modified grass fiber, part 1: Characterization of grass fiber and assessment of properties of polymer modified fiber

“…Graft copolymerization of vinyl monomers onto natural fibers have been studied using peroxydisulfate. [12][13][14][15] Agarwal and Sreenivasan 16,17 have studied graft copolymerization of methyl methacrylate (MMA), acrylonitrile (AN), vinyl acetate (VA) and styrene onto jute fibers by gamma radiation. Mishra et al 18 grafted MMA onto chemically modified jute fibers.…”

Graft copolymerization of benzyl methacrylate onto wool fibers

“…Arai and coworkers [6][7][8][9][10][11][12][13][14][15] have made extensive work on the graft copolymerization of vinyl monoThe chemical modification of wool through graft mers onto wool fibers. Grafting, i.e., in situ formacopolymerization of vinyl monomers can be effection of vinyl polymers, can be accomplished by tive in improving some fiber properties and endmeans of the free radical initiation mechanism.…”

Grafting vinyl monomers onto wool fibers. I. Graft copolymerization of methyl methacrylate onto wool using V5+–thiourea redox system

“…In all the initiating systems containing thiourea (I) the redox component is isothiourea18 (11), a thiol (existing in a tautomeric equilibrium with thiourea in an aqueous solution) is the reductant. The generation of a free radical in this system takes place by the abstraction of the reactive hydrogen atom attached to the sulfur atom in isothiourea generating the amidinosulfenyl radical (111) ,NH, NH…”