Improved cationic dyeability of thermotropic liquid crystal polyarylate fabrics by ultraviolet irradiation-induced grafting of acrylic acid

Abstract

As one of the most promising high-performance fibers, it is worthwhile to investigate the dyeing property of thermotropic liquid crystal polyarylate (TLCP) fibers. In this work, ultraviolet (UV) irradiation-induced grafting using the acrylic acid (AAc) method was employed to improve the cationic dyeability of the TLCP fabrics. The TLCP fabrics were firstly immersed in an AAc monomer solution for 24 h, followed with the UV radiation process for grafting polymerization. The results showed that the dyeing performance to C.I. Basic Red 46 of the modified TLCP fabrics was remarkably improved. Through several characterizations, it was found that the AAc-grafted TLCP fibers became more roughened with many pits on the fiber surface, while the crystalline structure of the TLCP fibers was hardly affected. More importantly, carboxyl groups have been successfully introduced onto the TLCP fiber surface, which is the main reason for the good dye uptake. Therefore, this paper provides a simple and efficient way for the improvement of the cationic dyeing property of TLCP fabrics.