SCREENING OF EFFECTIVE FACTORS ON GELATION TIME OF HYDROGELS

In this work, a hydrogel was prepared by crosslinking of aqueous solutions of sulfonated polyacrylamide/chromium triacetate in purpose ofwater shut off treatment. In order to screen theeffective factors on the gelation time and investigate their interactions, fractional factorial design methodwas used in experimentation with eight factors (pH, CaCl2 concentration, crosslinker/co-polymer ratio, NaCl concentration, co-polymer concentration,sodium lactate, nanoclay and thiouria) and one response (gelation time). Furthermore, the analysis of variance (ANOVA) was implemented as a significanttool to evaluate the quality of the quadratic model which was shown the 99% confidence limit of significant. Among the eight factors, sodium lactate,co-polymer concentration, nanoclay, thiouria and crosslinker/co-polymer ratio were the main effects respectively and the interactions between sodium lactate and crosslinker/co-polymer ratio, pH and crosslinker/co-polymer ratio were highly effective