US EPA

8332397 

Meetings & Symposia 

Use of assciating polymers as multi-functional thickeners - Studies of their structure in aqueous solutions and rheology measurement 

Nakamura, A; Nakajima, Y; Fukuhara, T; Inoue, H; Yoshida, K; Kaneda, I 

2006 

55 

2 

5682 

Japanese 

A novel thickener that associates in aqueous solutions via hydrophobic force resulting in polymer network formation was developed. The structure of the polymer in aqueous solutions was studied by using NMR, quasi-elastic light scattering (QELS), fluorescence, and rheology measurements. The measurement of the pyrene fluorescence spectra showed that the polymer begin to form aggregates at 3×10-4%. The solution viscosity slightly increased with increases in the concentration of the polymer below 0.4%: η ∼ C 0.5. On the other hand, it dramatically increased with increasing the polymer above the transition concentration (∼ 0.4%): η ∼ C 9. These results suggested that part of the polymers starts to bridge micelles, forming inter micelle networks. Because we designed our polymer to provide powerful thickening effect, it bears long end alkyl chains (C 24), resulting it to form aggregates and increase the viscosity even at low polymer concentrations. Since the mechanism of thickening for this polymer dose not depend on electrostatic force but hydrophobic interaction, the thickening ability is little affected by pH and addition of salt. 

Associating polymer; Rheology; Solution properties; Thickener