Synthesis And Rheologic Behavior Of Hydrophobically Associating PAM

Hydrophobically modified water-soluble polymer is a polymer with a fewhydrophobic groups in the hydrophilic macromolecular chain．The polymer solutionhas unique rheology because of its amphiphilic molecular structure．For their specialproperties of higher temperature resistance and salt tolerance, hydrophobicallymodified polyacrylamide(HMPAM) have been widely used in the industry．It was shown that polyacrylamide (PAM) mainly undergoes degradation underγ-irradiation. The study was carried out on experimental condition under whichdegradation was the least．The hydrophobically modified water-soluble copolymers,hydrophilic polyacrylamide grafted with AMPS and hydrophobic octadecyl acrylate,were synthesized by radiation grafting reaction．Pre-irradiation graft copolymerization and co-irradiation graft polymerizationwere used in this work．Pre-irradiation graft copolymerization included twotechnologies, pre-irradiation of PAM with solution graft copolymerization andpre-irradiation of PAM with micelle graft polymerization．The aqueous solutionviscosities of HMPAM made by these two technologies were higher than that ofPAM．Also we find that the aqueous solution viscosities of HMPAM made bypre-irradiation micelle graft polymerization were higher than that of HMPAM madeby pre-irradiation solution graft copolymerization．Co-irradiation graft polymerization also refered to two technologies,which wereco-irradiation graft under swollen state and co-irradiation graft under solidphase．Crosslinking often happened under swollen state resulting to the indissolubilityof the product in water. While co-irradiation graft under solid phase was easy carriedout and crosslinking could be well prevented．Studies on the best experimentalconditions including irradiation time, concentration of octadecyl acrylate and differentratio of octadecyl acrylate to AMPS were carried out．The viscosity test showed that the aqueous solusion rheology of HMPAM wereimproved obviously compared with that of PAM,which refered to higher temperatureresistance and salt tolerance．...