A SURFACE MODIFIED SUPERABSORBENT POLYMER (MSAP) HAS BEEN PREPARED VIA ESTERIFICATION OF CARBOXYLIC ACID GROUPS ON INITIAL SAP WITH BENZYL CHLORIDE USING 1, 1, 3, 3-TETRAMETHYLGUANIDINE (TMG). EFFECT OF VARIOUS PARAMETERS SUCH AS REACTION TIME AND WATER FRACTION OF THE REACTION SOLVENT MIXTURE ON WATER ABSORPTION OF MSAP WERE INVESTIGATED. RESULTS INDICATE THAT THE AMOUNT OF SWELLING WAS DECREASED WITH INCREASING OF THE WATER FRACTION AND REACTION TIME. HOWEVER, OTHER PROPERTIES SUCH AS UNWANTED PHENOMENON CALLED GEL BLOCKING WAS REDUCED, LEAD TO IMPROVED WATER PERMEABILITY.