Synthesis of Gemini Surfactants and Application to Make Specialty Fatliquors
Nasim Kamely, Md. Sayem Alam* and Asit Baran Mandal
Council of Scientific and Industrial Research (CSIR) — Central Leather Research Institute (CLRI), Industrial Chemistry Laboratory, Adyar, Chennai 600 020, India E-mail: sayemalam@gmail.com,
sayem@clri.res.in, abmandal@hotmail.com, abmandal@clri.res.in Abstract: "Fatliquors", the most widely used wet chemical applied in the form of an emulsion on the blue wet (chrome) leather at the end process of tanning the leather to keep it soft, smooth, light and heat fasting by preventing the fibrils from aggregation and filling the voids of the fibrils in dried leather. It has the most pronouncing effect on the softness and tensile property of the leather. Fatliquors are emulsions so the use of emulsifier (e.g., surfactants) to stabilize the emulsion is necessary. Herewith, we report the synthesis, characterization of Gemini surfactants. Gemini surfactants are made up of two amphiphilic moieties connected at the level of the head groups or very close to the head groups by a spacer group [1,2]. Gemini surfactants have two hydrophilic groups and two hydrophobic groups per molecule, rather than the single hydrophilic and single hydrophobic group of conventional surfactants. The greater efficiency and effectiveness of Geminis (viz., surface activity (10 to 100 times more efficient, lower critical micelle concentration (CMC) (CMC is at least one order of magnitude lower, solubilization (better solubilizing), low Kraft temperature, etc.) over comparable conventional surfactants [1,2] make them more cost-effective as well as environmentally desirable.
Keywords: Gemini surfactants; Micelles; Emulsion; Fatliquors; Smart leather;
Acknowledgement: Thankful to Department of Science and Technology (DST), New Delhi, Govt. of India for the financial support.
References: 1. R. Zana, Adv. Colloid Interface Sci., 97, 205 (2002). 2. F. M. Menger, J. S. Keiper, Angew. Chem. Int. Ed. 39, 1906 (2000) (and the references therein).
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