Introduction of poly(acrylic acid) branch onto acetate starch for polyester warp sizing

Abstract

To investigate the effects of hydrophilic poly(acrylic acid) (PAA) branches grafted onto the backbones of acetate starch on the sizing performance, a series of acetate starch-g-poly(acrylic acid) (AS-g-PAA) with different grafting ratio of 6.71–10.04% were prepared by graft copolymerization in an aqueous medium. The effect of grafting conditions on grafting ratio and efficiency were investigated. The adhesion was evaluated by measuring the bonding force of starch to the fibers and the abrasion resistance of sized polyester yarn, whereas the film properties were investigated in terms of tensile strength, breaking elongation, degree of crystallinity, and swelling capacity. It was confirmed that the PAA branch can effectively improve the adhesion ability of acetate starch to polyester fibers, film mechanical characters, and also enhance the abrasion resistance of polyester yarns to 148.9%. The degree of crystallinity of the acetate starch film was decreased which led to mitigate the brittleness of film. The SEM observations confirm that the fibers in the yarn fit snugly together after sizing. The AS-g-PAA showed great potentiality for the application in polyester warp sizing.