Acta Phys. -Chim. Sin. ›› 2015, Vol. 31 ›› Issue (4): 715-721.doi: 10.3866/PKU.WHXB201503028

• SOFT MATTER • Previous Articles     Next Articles

Effect of Branched Cationic and Betaine Surfactants on the Wettability of a Poly(tetrafluoroethylene) Surface

YUAN Fu-Qing1,2, LIU Dan-Dan3, GUO Lan-Lei2, ZHU Yang-Wen2, XU Zhi-Cheng3, HUANG Jian-Bin4, ZHANG Lei3, ZHANG Lu3   

  1. 1 College of Petroleum Engineering, China University of Petroleum (Huadong), Qingdao 266555, Shandong Province, P. R. China;
    2 Geological Scientific Research Institute of Shengli Oilfield Co. Ltd., SINOPEC, Dongying 257015, Shandong Province, P. R. China;
    3 Technical Institute of Physics and Chemistry, Chinese Academy of Sciences, Beijing 100190, P. R. China;
    4 College of Chemistry and Molecular Engineering, Peking University, Beijing 100871, P. R. China
  • Received:2015-01-08 Revised:2015-02-10 Published:2015-04-03
  • Contact: ZHANG Lu E-mail:luyiqiao@hotmail.com
  • Supported by:

    The project was supported by the Important National Science & Technology Specific Projects of China (2011ZX05011-004).

Abstract:

The adsorption mechanism and wetting properties of aqueous solutions of branched cationic surfactants, hexadecanol glycidyl ether ammonium chloride (C16GPC), and zwitterionic surfactant, hexadecanol glycidyl ether glycine betaine (C16GPB) on a poly(tetrafluoroethylene) (PTFE) surface were investigated using sessile drop analysis. The influences of surfactant concentration on surface tension, contact angle, adhesional tension, PTFE-solution interfacial tension, and adhesion work were expounded. The results indicate that branched surfactant molecules lie parallel to the PTFE surface through hydrophobic interactions between the multi methylene groups of the alkyl chain and the solid surface below the critical micelle concentration (cmc). C16GPC and C16GPB molecules still adsorb onto PTFE because of the marked hindrance of branched chains to the formation of micelles above the cmc. The methylene group interactions with PTFE decrease and C16GPC and C16GPB molecules become straightened on the solid surface, which results in a clear decrease in PTFE-solution interfacial tension (γsl). For branched surfactants, an abrupt decrease in contact angle appears above the cmc.

Key words: Cationic surfactant, Zwitterionic surfactant, Branched chain, Contact angle, Poly(tetrafluoroethylene) surface

MSC2000: 

  • O647