Immobilizing of polyethyleneimine on bamboo viscose fiber using epichlorohydrin crosslinker for enhancing adsorption ability with lac dye

Abstract

Immobilization of polyethyleneimine (PEI) on bamboo viscose fiber using epichlorohydrin (ECH) crosslinker (ABF-e-PEI) was employed to enhance the ability of dyeing with lac. The results from morphological observation, thermal degradation behavior, Fourier transform infrared (FTIR) analysis, x-ray photoelectron spectroscopy (XPS) and x-ray diffraction (XRD) clearly revealed the success of PEI-immobilizing on fiber surface with no significant change in intrinsic properties of the fiber after modification. The modified fiber exhibited fast and efficient adsorption with the adsorption capacity >90 mg/g which was much higher than that of the unmodified adsorbent (did not exceed 10 mg/g). The results from kinetic and isotherm studies showed that the adsorption process conformed to the pseudo-second-order, intra-particle diffusion and Langmuir models. Adsorption temperatures have less effect to the adsorption performance of the modified adsorbent. Electrostatic ion-dipole interaction between protonated amines of PEI and negative charged sites of lac dye was the main proposed mechanism. Good resistance of color changes for ABF-e-PEI was confirmed by the color-fastness assessment (grade 4–5), suggesting efficient method of PEI-immobilizing using ECH crosslinker. The binding reaction of between amine groups of PEI and hydroxyl groups of the cellulosic fiber using ECH crosslinker can be expected to have a broad potential application in dyeing processes or pollution treatments due to its simple, cost-effective, flexible and efficient method.