Amberlite XAD-4, the commercial form of poly(divinylbenzene-co-ethylvinylbenzene), was modified by bromohydration and bromination of its pendant vinylbenzene groups. The vinylbenzene groups were completely converted to (1,2-dibromoethyl)benzene groups, with a degree of functionalization of 35%. Bromohydration of XAD-4 created a resin with (1-hydroxy-2-bromoethyl)benzene groups, with a degree of functionalization of 24%. Further modifications to the (1,2-dibromoethyl)benzene groups of the brominated resin were done using thiourea, which led to a resin with a mixture of functional groups, including isothiouronium bromide; and using N,N-dimethylthioformamide with subsequent methanolysis, which led to a resin with thiol groups.