Abstract: Hydrolysiskinetics of reactive dye in dye/D5 suspending system has been investigated using HPLC. In order to explore the mechanism that dyeing in reactive dyes/D5 suspending system can get high fixation ratio since just a little water was used. Hydrolysis kinetics was studied using C.I. reactive195, at pH11, temperature interval of 60,70 and 80℃, in simulation hydrolysis conditions. This study has shown that hydrolysis of dye in dye/D5 suspending system was very lower to that in aqueous system. The amount of complete hydrolysis dye reduce 27.8% at 60℃, 57.8% at 70℃, 51.1%at 80℃, hydrolyzed 90min at pH11. And at the same temperature, the rate constantswas1.8 times lower than the rate constant in aqueous system. When hydrolysis performed in the presence of fabric in dye/D5 suspending system, the amount of complete hydrolysis dye reduced while the rate constants also decreased.

Key words: reactive dye, D5(decamethyl cyclopentasiloxane), suspending system, hydrolysis kinetics, HPLC