溶剂浸渍树脂稳定化研究进展

溶剂浸渍树脂是由萃取剂浸渍于某种适宜的聚合物载体上制备而成,其主要不足在于其中的萃取剂容易从载体中流失,从而导致其吸附容量逐步降低、使用周期缩短,进而影响树脂的稳定性.为提高其稳定性可以通过选用反应性载体或对载体进行改性、在常规浸渍树脂颗粒外包覆一层高分子膜来实现.前者主要有硝化、表面活性剂改性等改性方式,后者包覆使用的膜材有聚砜、二甲基甲酰胺(DMF)、聚乙烯醇(PVA)等,其中以PVA作膜材时采用的交联剂有乙烯砜、戊二醛、硼酸等.

Research Progress in Stabilization of Solvent Impregnated Resins

Solvent impregnated resins （SIRs） are usually prepared simply by impregnating the selected polymeric support with the extractant. The main disadvantage of SIRs is their low stability because of the extractant leakage from the polymeric support that results in the gradual loss of SIRs capacities and the shortening of their lifetime. To improve the stability of SIRs, the reactive support can be selected or the tradition support can be modified. Post-encapsulation of SIR beads with thin polymeric film can also prevent leakage of the extractant to stabilize the capacity of freshly prepared SIR samples. The main modified methods of pre-treatment are nitration and modified by surfactant. The coating materials of post-treatment used include polysulfone, dimethylformamide （DMF）, poly （vinyl alcohols） （PVA） et al. And the crosslinking agents such as divinyl sulfone, glutaraldehyde and boric acid are used when PVA is as the coating material.