Properties of Radicals Formed by the Irradiation of Wool Fibers

Shanghai Institute of Applied Physics, Chinese Academy of Sciences, China.
Journal of Radiation Research (Impact Factor: 1.8). 04/2004; 45(1):77-81. DOI: 10.1269/jrr.45.77
Source: PubMed


Wool fibers of different sample conditions were irradiated in different atmospheres by (60)Co gamma-rays and were studied by electron spin resonance method (ESR). It was found that a large percentage of the alpha-carbon radicals of polymer main chain were more long-lived radicals. The ESR measurements of irradiated cortex samples of the wool fibers proved that most radicals from the cortex were long-lived ones. Low water content (as low as 27.5%) in the reaction system did not greatly affect the radical formation, but higher water contents would reduce the radical concentrations dramatically and accelerate their decaying process. The results will be of help in property modification of wool products by radiation graft copolymerization.

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