Influence of Spacer on Association Behavior and Thermodynamic Parameters of Dimeric Cationic

SupplementaryMaterial

Influence of Spacer on Association Behavior and Thermodynamic Parameters of Dimeric Cationic Surfactants.

Sanjeev Kumar* and Kushan Parikh

Soft Material Research Laboratory, Department of Chemistry, The Maharaja Sayajirao University of Baroda, Vadodara – 390 002, India.

Tel No.: +91-265-2795552, Fax: +91-265-2792277

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Figure Captions

Figure S1. Representative Fluorescence (emission) spectra of 2M pyrene in aqueous solution of CTAB (a) and IV (b) at 303 K.

Figure S2.Plot of Log cmc vs Temperature for CTAB in aqueous solution.

Figure S3. Representative Fluorescence (emission) spectra of 2 M pyrene in aqueous micellar solution of CTAB (a), I (b), II (c), III (d) and IV (e) at different quencher (CPC) concentrations, T = 303 K.

Figure S4.Representative plots of cmc determination by (a) conductometry and (b) fluorometry for CTAB at 303 K in aqueous solution.

Figure S5. Stern-Volmer plots for the fluorescence quenching of 2 M pyrene in micellar aqueous solution of I to IV and CTAB at 303 K.

Table Captions

Table S1. Various Micellization (cmc and α) of CTAB in Aqueous solution at Different Temperatures (T).

Table S2. Various Micellization (cmc and α) of I to IV in Aqueous solution at Different Temperatures(T).

Synthesis of cleavable spacers:

Spacers (d to f, see scheme S1) were synthesized by the general method of esterification and amidation. Chlroacetylchloride (CAC, 0.22 mol) was placed in dried, three necked, round-bottomed flask (RBF) equipped with a magnetic stirrer, a thermometer, a condenser closed with a calcium chloride drying tube and an additional funnel. (a) or (b) (0.1 mol) was added per drops via additional funnel in N2 atm while for Spacer (f), (c) (0.1 mol) was taken in RBF and CAC was added drop wise. The mixture was maintain to 50˚C and remained for 8 to 16 hrs for (d) and (e), respectively. However, for spacer (f) reaction was maintain at 0-5˚C for 8-12 hrs for complete conversion. After the reaction completed, the HCl gas generated in the reaction was removed under very high N2 pressure and with slight warming. A small group of water was added to the residue, and mixture was transfer into separating funnel, then saturated NaCl was added to the mixture. The organic phase was washed with saturated NaCl several times until it was neutral. The product was dissolved in dichloromethane and dried over to sodium sulphate and then remove dichloromethane under vacuum. At last, the product (d) (e) and (f) were obtained as colourless needle type crystal. The yield was around 70 to 80 %, respectively.

Scheme S1 Synthesis route of various spacers (d to f).

Fig. S1 Representative Fluorescence (emission) spectra of 2M pyrene in aqueous solution of CTAB (a) and IV (b) at 303 K.

Fig. S2Plot of Log cmc vs Temperature for CTAB in aqueous solution.

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Fig.S3Representative Fluorescence (emission) spectra of 2 M pyrene in aqueous micellar solution of CTAB (a), I (b), II (c), III (d) and IV (e) at different quencher cetylpyridiniumchloride (CPC) concentrations, T = 303 K.

Fig.S4Representative plots of cmc determination by (a) conductometry and (b) fluorometry for CTAB at 303 K in aqueous solution.

Fig. S5 Stern-Volmer plots for the fluorescence quenching of 2 M pyrene in micellar aqueous solution of CTAB and I to IV at 303 K.

Table S1Various Micellization (cmc and α) of CTAB in Aqueous Solution at Different Temperatures (T).

Table S2 Various Micellization (cmc and α) of Dimeric Surfactants (I to IV) in Aqueous solution at Different Temperatures (T).

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