Dilational Rheological Properties of Fluorocarbon Modified Poly(acrylamide)s at the Air/Water Surface

Abstract

A series of fluorocarbon modified poly(acrylamide)s containing low amounts (0.1–1.5 mol%) of fluorocarbon (CF₃(CF₂)₅–) are synthesized by copolymerization of acrylamide with 2-(perfluorohexyl) ethyl acrylate). The dynamic surface tension results show that the efficiency and effectiveness of the copolymers to lower surface tension increase with increasing the fluorocarbon content. The results of surface dilational viscoelasticity show that with the increase of the fluorocarbon content, the dilational viscoelasticity increases at the low concentration (<0.5 wt%), but firstly increases and then decrease at high concentration (>0.5 wt%). Furthermore, temperature has effect on the dilational viscoelasticity of the adsorbed layer in different extents.

Keywords:

• Dilational rheological properties
• fluorocarbon
• polymer adsorption layers
• surface viscoelasticity

Acknowledgements

The authors gratefully acknowledge the financial support from Major Research of the Ministry of Science and Technology, China (Grant No. 2008ZX05024-02-007) and National Basic Research Program of China (973 Program, 2009CB930103).

Notes

^aDetermined via static laser light scattering in a mixture of formamide and water (25:1 in volume fraction) at 25°C.