| Abstract
| - Hydrophobically associating copolymers of acrylamide (AM) with a small amount of 4-(ω-propenoyloxyethoxy)benzoic acid (PEBA, <2.5%) were synthesized by template copolymerization in the presence of poly(allylammonium chloride) (PAAC) as a template in an aqueous medium. These template copolymers exhibitedremarkable thickening properties due to the effective hydrophobic association, which were similar to thosecopolymers with a multiblock structure obtained by the micellar process. The pH of the reaction medium andthe molecular weight of the template strongly influenced the thickening properties of the products. In theexperimental range, the higher the PEBA content, the larger the thickening capacity of these hydrophobiccopolymers. The aggregate behaviors of these copolymers were studied by fluorescence, transmission electronmicroscopy (TEM), and light scattering techniques. The apparent critical interpolymer aggregate concentration(cac) of the copolymer solution was about 0.5 g/dL. As the concentration of the copolymer became higherthan the cac, the aggregates changed their morphology from small hollow spheres to big flower-shapedaggregates. All the above results indicated that the template copolymerization gave access to a very simpleand powerful means for the preparation of hydrophobically associating copolymers and other functional polymermaterials.
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