Effect of Scouring and Bleaching on Chemical Modification of Cotton Sliver by EB-Induced Graft Polymerization

A cotton fabric has high water absorption and good touch, so it has been used as clothes since ancient times. Electron beam (EB) induced graft polymerization is one of the chemical modification methods for polymer materials such as fibers and films. In this study, it was shown that uniform modification can be achieved through EB-induced graft polymerization even with unrefined cotton sliver. The Cotton sliver can be used not only for fabrics but also for knits and nonwoven fabrics and so on. ESR spectroscopy and the degree of grafting showed that the amount of radical generated in the original sliver was smaller than that for the sliver after scouring and bleaching. A more remarkable difference was observed in the amount of active radical that could initiate the graft polymerization. Nevertheless, it was possible to modify the cotton sliver that had not been scoured and bleached through the EB-induced graft polymerization if the graft polymerization could be completed within 90 min. Microprobe Raman spectroscopy revealed that the generated graft chains were uniformly distributed inside the sliver. A comparison of the reactivity of monomers in different dispersion states in water showed that the monomers forming small dispersion units in water tended to have the higher degree of grafting. The diffusion process in which the monomer reaches the active site in the sliver before their disappearance must be key process for the graft polymerization to proceed.