| In this paper, the novel hydrophobic monomer, arylalkylacrylamide (BAAM), was synthesized. And then the nonionic (PBAM series) and ionic (PBAMS) hydrophobically associating water-soluble copolymers were synthesized by micellar free radical copolymerization method. After the study on the synthesis reaction of PBAM series copolymers, it was found that the polymerization kinetics of acrylamide in water system could still be used in micellar polymerization process, and that the initial incorporation of BAAM into polymer was higher and the acrylamide homopolymerization was dominant at the higher conversion period of monomer, which resulted serious micro-structure heterogeneity of copolymer and had a very important effect to the viscosity properties. It's the first time to use multi-indexes comprehensive evaluation method of orthogonal test to study the effect of the amount of AMPS, BAAM, SDS and initiator on the viscosity behavior of tripolymers. Then PBAMS copolymer was prepared. Polymer structure was characterized by IR. From the TG analysis, two kinds of polymers have good thermal stability, and that of PBAMS is better than that of PBAM series.For PBAM series copolymers, there had an optimum amount of BAAM, and the relationship between the amount of BAAM and the viscosity behavior was different to monotone increasing or "saddle shape" variation. The same influence to the solution viscosity of PBAMS was complicated, and higher dosage of BAAM resulted the insolubility of copolymers. With the increasing of the amount of AMPS, the viscosity of both aqueous and NaCl solution of PBAMS was firstly increased* Sponsored by the Major State Basic Research Project of China (G199022502).IVand then kept unchanged.When polymer concentration was higher than the critical association concentration (CP*), the viscosities of two kinds of copolymers increased abruptly. The addition of NaCl and the copolymerization with ionic monomer (AMPS) would decrease CP*. The solution of PBAMS and certain PBAM samples exhibited salt-thickening behavior. The influence of pH value on the viscosity of PBAMS was "saddle shape" variation. In some low temperature range, the solution of PBAM copolymers exhibited temperature-thickening behavior. However, high temperature would decrease the viscosity, and the temperature-rising process would decrease the viscositying ability of copolymers.The aqueous solution of two kinds of copolymers exhibited shear-thinning and thixotropy behavior. The Oswald model fitting revealed that the solution of two kinds of copolymer was pseudopalstic, especially the PBAMS solution was characteristic of yield point. The higher the polymer concentration, the stronger the pseudoplastic and the thixotropy behavior, and the higher the yield stress. The viscosity of aqueous polymer solution exhibited obvious time-dependent properties. Several times of shearing would decrease the viscosifying ability of copolymers, and the viscosity restoring needed some time. Appropriate addition of NaCl would increase the viscosifying ability and the thixotropy behavior. The NaCl solution of copolymers exhibited shear-thickening behavior at lower shear rate, and the pseudoplastic behavior under higher shear rate. It was found in this paper that to some extent the shearing could offset the molecular contraction introduced by NaCl.The linear viscoelastic measurement results showed that for PBAM copolymer solutions the elastic behavior was dominant after certain frequency. The higher the polymer concentration, the stronger the viscoelastic behavior, and the longer the relaxation time of molecular. The elastic behavior was dominant only after certain angular frequency for lower PBAMS concentration solution, but dominant at all test frequency range for higher PBAMS concentration solution. With the increase of frequency, the loss tangent value of copolymer NaCl solution decreased slowly, which meant that the elastic feature of salt solution was stronger gradually.Furthermore, the PBAMS NaCl solutions were all dominant by e...
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