Macromolecules, 31 (8), 2527 -2532, 1998. ma9714171 S0024-9297(97)01417-4
Web Release Date: March 31, 1998

Copyright © 1998 American Chemical Society

Effect of Incorporating a Trace Amount of Fluorocarbon into Poly(N-isopropylacrylamide) on Its Association in Water

Yubao Zhang, Mei Li, Qing Fang, Yun-Xiang Zhang, Ming Jiang, and Chi Wu*

Department of Chemistry, The Chinese University of Hong Kong, Shatin, Hong Kong, Institute of Macromolecular Science, Fudan University, Shanghai 200433, China, Shanghai Institute of Organic Chemistry, Academia Sinica, Shanghai 200032, China, and The Open Laboratory for Bond Selective Chemistry, Department of Chemical Physics, University of Science & Technology of China, Hefei, Anhui, China

Received September 25, 1997

Revised Manuscript Received January 22, 1998

Abstract:

A combination of laser light scattering (LLS), viscometry, and fluorescence spectroscopy was used to study the association of a series of fluorocarbon-modified poly(N-isopropylacrylamide) (PNIPAM) copolymers in aqueous solution. The interchain association increases as both the fluorocarbon content and polymer concentration increase, evidenced by the changes of the apparent molar mass, intrinsic viscosity, Huggins constant, and fluorescence excimer-to-monomer intensity ratio. The LLS results are well-represented by the open association model. Our results also revealed that the intrachain association starts when each polymer chain, on average, has more than two fluorocarbon monomers.