Hydrophobically-modified polyacrylamides prepared by micellar polymerization

The characteristic features of hydrophobically-modified polyacrylamides (HM PAM) prepared by a micellar polymerization technique are reviewed. This met hod of synthesis leads to copolymers in which the hydrophobic units are ran domly distributed as small blocks in the acrylamide backbone. Special empha sis is put on the improvement of the technique so that well characterized a nd homogeneous samples are synthesized. The effect of the various parameter s controlling the rheological behavior of HMPAM is thoroughly analyzed. In particular, it is shown that a determining factor for a good thickening abi lity is the copolymer microstructure, i.e. the hydrophobe distribution. Som e recent advances are presented towards a better understanding of the assoc iation structure, thus allowing the design of tailored materials with good controllable rheological properties. (C) 1999 Elsevier Science B.V. All rig hts reserved.