Improved dyeability of polyacrylonitrile fibers by radiation grafting with vinylpyrrolidone

Abstract

X-ray, γ-ray, and electron irradiations are used to graft vinylpyrrolidone, a dye acceptor molecule, to a synthetic fiber, polyacrylonitrile. Two processes are described. In one, doses of 10–60 krad are given to the polymer–-aqueous monomer system at dose rates of 3–27 krad/min. In the other process, 0.2–3.0 Mrad is given the system at 0.5–90 Mrad/sec., followed by a heat treatment to elongate the graft side chain. Oxygen inhibits the grafting and various inorganic salts such as sulfates and phosphates enhance the grafting.