A quaternary ammonium group-grafted cation resin and a preparation method thereof are provided. The preparation method includes: adding a chloromethylated cross-linked polystyrene (PS) resin, trimethylamine hydrochloride, and a 20% sodium hydroxide aqueous solution successively to a reactor for a reaction under stirring at 30° C. to 40° C.; filtering a resulting reaction solution, followed by washing and drying to obtain a quaternary ammonium group-grafted resin; adding the quaternary ammonium group-grafted resin, 1,2-dichloroethane, silver sulfate, concentrated sulfuric acid, and fuming sulfuric acid successively for a reaction for 1 hour at 50° C. to 60° C., a reaction for 1 hour at 70° C. to 80° C., and a reaction for 5 hours at 115° C. to 125° C.; and cooling a resulting reaction solution to room temperature, followed by diluting, filtering, washing and drying to obtain the quaternary ammonium group-grafted cation resin.

A quaternary ammonium group-grafted cation resin and a preparation method thereof are provided. The preparation method includes: adding a chloromethylated cross-linked polystyrene (PS) resin, trimethylamine hydrochloride, and a 20% sodium hydroxide aqueous solution successively to a reactor for a reaction under stirring at 30° C. to 40° C.; filtering a resulting reaction solution, followed by washing and drying to obtain a quaternary ammonium group-grafted resin; adding the quaternary ammonium group-grafted resin, 1,2-dichloroethane, silver sulfate, concentrated sulfuric acid, and fuming sulfuric acid successively for a reaction for 1 hour at 50° C. to 60° C., a reaction for 1 hour at 70° C. to 80° C., and a reaction for 5 hours at 115° C. to 125° C.; and cooling a resulting reaction solution to room temperature, followed by diluting, filtering, washing and drying to obtain the quaternary ammonium group-grafted cation resin.

A liquid composition comprising a polymer having pendant groups of the formula I: (I) Wherein X is either a bond or is a linking group having 1 to 8 carbons and optionally 1 to 4 heteroatoms selected from O, N and S; and n is 1 to 4. ##STR00001##

A quaternary ammonium group-grafted cation resin and a preparation method thereof are provided. The preparation method includes: adding a chloromethylated cross-linked polystyrene (PS) resin, trimethylamine hydrochloride, and a 20% sodium hydroxide aqueous solution successively to a reactor for a reaction under stirring at 30 C. to 40 C.; filtering a resulting reaction solution, followed by washing and drying to obtain a quaternary ammonium group-grafted resin; adding the quaternary ammonium group-grafted resin, 1,2-dichloroethane, silver sulfate, concentrated sulfuric acid, and fuming sulfuric acid successively for a reaction for 1 hour at 50 C. to 60 C., a reaction for 1 hour at 70 C. to 80 C., and a reaction for 5 hours at 115 C. to 125 C.; and cooling a resulting reaction solution to room temperature, followed by diluting, filtering, washing and drying to obtain the quaternary ammonium group-grafted cation resin.

A quaternary ammonium group-grafted cation resin and a preparation method thereof are provided. The preparation method includes: adding a chloromethylated cross-linked polystyrene (PS) resin, trimethylamine hydrochloride, and a 20% sodium hydroxide aqueous solution successively to a reactor for a reaction under stirring at 30 C. to 40 C.; filtering a resulting reaction solution, followed by washing and drying to obtain a quaternary ammonium group-grafted resin; adding the quaternary ammonium group-grafted resin, 1,2-dichloroethane, silver sulfate, concentrated sulfuric acid, and fuming sulfuric acid successively for a reaction for 1 hour at 50 C. to 60 C., a reaction for 1 hour at 70 C. to 80 C., and a reaction for 5 hours at 115 C. to 125 C.; and cooling a resulting reaction solution to room temperature, followed by diluting, filtering, washing and drying to obtain the quaternary ammonium group-grafted cation resin.