Abstract
In order to modify the hydrophobic property of polyethylene terephthalate (polyester) fiber, some hydrophilic monomers such as acrylic acid, acrylamide and the like were graft-polymerized onto the fiber using ceric salt as an initiator. As the commercial polyester fiber was previously drawn and heat-treated, its fine structure becomes so compact and impenetrable that its graftreactivity is very small. Various pretreatments of the fiber were tried in order to increase its reactivity and was found that treatment with benzyl alcohol (150°C, 1_??_2 hr) was effective though accompanied with about 20% shrinkage of the fiber.
The grafting medium consisted of a hydrophilic monomer, acetic acid, water and ceric salt and the pretreated fiber was allowed to react in the medium under nitrogen atmosphere and with constant shaking. Influence of conditions upon the grafting was investigated and some properties of grafted fibers were measured.
Grafting percent of acrylic acid was more than 30%, while that of acrylamid was less than 20%. The moisture regain of the fiber could be increased to more than 10% at RH 65%, when the grafted polyacrylic acid was converted to Na or Ca salt. Also, the dyeability of the fiber could be increased towards cationic, basic or acid dyes.
