Hydrophobically associated polyacrylamide was synthesized by copolymerization of acrylamide (AM) and a surface-active monomer

sodium 2-acrylamidotetradecane sulfonate (NaAMC14S)

in an aqueous homogenous phase system.Based on the exploited copolymerization mechanism and by controlling the concentration of NaAMC14S above its critical micelle concentration

copolymers NaAMC14S/AM with microblocks structure were obtained.By varying the feed ratio of NaAMC14S and AM

the added amount of electrolyte NaCl and the amount of initiator

respectively

thre series of copolymers NaAMC14S/AM with various microstructures were prepared.The dependences of hydrophobic associating properties of the copolymers on the microstructures were studied by the fluorescence probe method and the apparent viscosity measurement method

and the effects of the content and length of the hydrophobic blocks and the molecular weight of the copolymers were explored thoroughly.The experimental results show that the hydrophobic associating properties of copolymers NaAMC14S/AM is strengthened with the increase of the content and length of the hydrophobic blocks and is enhanced with the increase of the molecular weight of the copolymers.