Novel additives including charge-transfer complexes in grafting of methyl methacrylate to polypropylene, cellulose and wool, initiated by ionizing radiation and UV: significance of these studies in analogous curing processes

Radiation induced graft copolymerization of vinyl monomers and their binary mixture onto rayon fibre

“…The formation of such a complex decreases the diffusion of the monomer to the active sites leading to the decrease in percentage of grafting. Similar observations have been made by Garnett et al20 and Kaur et al21…”

“…The formation of such a complex decreases the diffusion of the monomer to the active sites leading to the decrease in percentage of grafting. Similar observations have been made by Garnett et al 20 and Kaur et al 21 Thus, from the foregoing discussion, it is observed that there exists an optimum total dose for affording maximum percentage of grafting, which varies with the type of the monomer used for grafting. If the number of active sites generated on irradiation was the only reason for affording maximum percentage of grafting then all the monomers regardless of their reactivity would have produced maximum grafting at a single total dose under optimum conditions.…”

“…The addition of VI to EA in a binary mixture also affects the grafting of the later. In addition to this both these monomers are held in charge transfer complex, which hinders their reactivity towards grafting 20. Maximum grafting (32%) of the binary mixture (EA + VI) is also less than that obtained with EA (40%) and is obtained at a little lower total dose (2.4 M rad).…”

Chemical and mechanical properties of butyl methacrylate grafted wool fiber

“…It has been reported in the literature that polymer‐grafted wool fibers and fabrics have better shrinkage resistance 7, 18. Hence, this study was aimed at demonstrating that the chemical and mechanical properties of modified wool fibers could be significantly improved by relatively low levels of grafting while the intrinsic fiber properties were maintained.…”

“…Unfortunately, both of these processes produce unavoidable tensile strength damage to modified wool. Another process, the grafting copolymerization of vinyl monomers to wool, which has been reported extensively3–11, 17–20 during the last 3 decades, has not been popular because grafting copolymerization, especially at high grafting percentages, can have some side effects on wool (e.g., stiffness and slightly poor handle). However, some reports9, 17, 18 have shown that with suitable polymerization systems (highly reactive monomers and redox couple initiators) and polymerization conditions (lower grafting percentages and relatively low reaction temperatures), grafting copolymerization can be accomplished without deleterious effects on wool handle and end‐use performance.…”