Environmentally friendly preparation of a strong basic anion exchange fibers and its application in sugar decolorization

An efficient route for the synthesis of a strong basic anion exchange fibers is described. In this synthesis route, the commercially available p-chloromethylstyrene was directly grafted onto a polypropylene fiber substrate, which eliminated the need of the highly carcinogenic chloromethyl methyl ether in the chloromethylation of grafting fiber. Several interdependent parameters such as monomer concentration, bath ratio and the influence of solvents on the grafting copolymerization were investigated. The removal efficiency of sugar colorants by the anion exchange fibers was evaluated. The results show that simultaneous irradiation and grafting p-chloromethylstyrene onto polypropylene fiber can obtain a good grafting level under appropriate conditions. The optimal monomer concentration and bath ratio are 40% and 1:30 for a moderate grafting degree and the suitable solvent is toluene. The grafted fiber changed from flexible to rigid. And the prepared material maintains stable before 134.5 °C. The static ion exchange capacity of the synthesized anion exchange fiber is up to 4.72 mmol g⁻¹ and the fiber possesses better ability to remove sugar colorants. The experimental results indicate that the decolorization ratio of the product anion exchange fibers was greater than that of commercial material.