Synthesis characterization and performance properties of glycerol based non ionic gemini surf

1. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
INTERNATIONAL JOURNAL OF ADVANCED RESEARCH
IN ENGINEERING AND TECHNOLOGY (IJARET)
ISSN 0976 - 6480 (Print)
ISSN 0976 - 6499 (Online)
Volume 5, Issue 8, August (2014), pp. 62-69
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© I A E M E
SYNTHESIS, CHARACTERIZATION AND PERFORMANCE PROPERTIES
OF GLYCEROL BASED NON-IONIC GEMINI SURFACTANT WITH 1,
6-DIBROMOHEXANE AS SPACER
ISHWAR T. GAWALI*, GHAYAS. A. USMANI
Department of Oil Technology, University Institute of Chemical Technology,
North Maharashtra University, Jalgaon-425001, MS, India
ABSTRACT
The synthesis of novel glycerol based non-ionic Gemini surfactant was carried out in two
stages in the present research work. Initially glycerol was esterified using cotton seed oil at higher
temperature followed by reaction with 1, 6-dibromohexane to form the Gemini surfactant. The new
Gemini surfactant was characterized by FTIR, 1H-NMR and 13C-NMR spectroscopy. The surfactant
properties such as surface tension, critical micelle concentration, effectiveness, foaming power and
stability, emulsifying power, wetting power, dispersion capability, contact angle and solubilization
behaviour were studied.
Keywords: Gemini Surfactant, Characterization, Surface Activities, Performance Properties, Contact
Angle Measurement, Solubilization Behaviour.
1. INTRODUCTION
Surfactants are amphiphilic molecules that are capable of undergoing self-assembly into
aggregated system. These unique molecules generally consist of a polar head group and one or more
hydrophobic tails. As a consequence of the hydrophobic effect, the surfactants within the aggregated
assemblies are oriented with their polar head groups to the aqueous phase and their hydrophobic tail
away from the aqueous phase. Gemini surfactants are a newer type of surfactants capable of forming
self assemblies having two amphiphiles in molecules, chemically bonded through a spacer group.
They are more surface active by order of magnitude than conventional surfactants. They have good
water solubility and their ability to form micelles and lowering surface tension characteristics are
fairly good as compared to conventional surfactants. This newer type of surfactants has attracted
considerable interest since it became evident that these compounds have a very low critical micelles

2. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
concentration and much greater efficiency in reducing surface tension than expected [S. K. Hait et al,
2013, R. Janardhan et al, 2012, Wenjian Zhang et al, 2009].
63
There are several research publications on Gemini surfactants and their potential applications.
Aratani et al have synthesized Gemini surfactants from tartaric acid and studied properties. Anno
Wagennaar et al was synthesized non-ionic reduced-sugar based bola amphiphiles and gemini
surfactants with an , -diamino-(oxa) alkyl spacer. Wenjian Zhang et al synthesized Nonionic
Gemini Surfactant Di-Glycerol 2, 9-Dihexyldecanedioate and studied the physico-chemical
properties.
In the present research work, a new Gemini surfactant using glycerol as hydrophilic head
group and cotton seed oil as source of hydrophobic tail has been synthesized. There is industrial
important for the use of glycerol due to its low cost factor. Cotton seed oil contains linoleic acid as a
major component. Pure linoleic acid is not cost effective and may not be economic for the industrial
use. Synthesis involved initial trans-esterification of cotton seed oil with glycerol to form
monoglyceride which was then dimerised using 1, 6-dibromohexane. The prepared non-ionic Gemini
surfactant was characterized and surfactant properties were investigated in detail.
2. EXPERIMENTAL PROCEDURES
2.1 Materials and Equipment Setup- The cotton seed oil was procured from local market. Glycerol
with purity 99%, Calcium oxide, 1, 6-dibromohexane, Tetra-butyl ammonium bromide, Potassium
hydroxide were purchased from Merck. An infrared (IR) spectrum was obtained by SHIMADZU
FTIR 8400 in the 400-4000 cm-1 range using KBr pellets. 1H nuclear magnetic resonance (1H –NMR)
spectra were obtained with Bruker advanced 400 MHz NMR spectrophotometer. 13C nuclear
magnetic resonance (13C –NMR) spectra were obtained with Bruker advanced 400 MHz NMR
spectrophotometer.
2.2 Experimental section: Step 1- Synthesis of glycerol Ester from Cotton seed oil and Glycerol
by trnas-esterification reaction.
The experimental set up consisted of a 250 ml three necked round bottom flask equipped with
motor stirrer, a thermometer and condenser. The cotton seed oil (90 gm, 0.1 moles) was reacted with
glycerol (23gm, 0.25 moles) by using calcium oxide (1% of total amount of oil) as catalyst. Firstly,
the catalyst was dispersed in the oil. Then reaction mixture was heated to 80OC for half an hour and
temperature was increased to 210-230OC. The reaction was continued for three hours in the inert
atmosphere under the presence of nitrogen. The oil bath was used to maintain the constant
temperature. The formation of glycerol ester was analyzed by using solubility test in methanol [Wim
D. Bossaert et al, 1999].
Scheme-1 Synthesis of Glycerol ester from cotton seed oil
Step 2: Synthesis of gemini surfactant by using 1, 6 dibromohexane as spacer
Glycerol ester 0.1 mole (31.2 gm), KOH 90 ml (20%) and Tetra butyl ammonium bromide
(1 gm) were successively introduced in a 500 ml three necked round bottom flask and stirred
vigorously for 15 minute at 25OC. 1,6-dibromohexane was then added drop wise (12.1gm). At the

3. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
end of addition, temperature was raised to 100OC and mixture was stirred vigorously for 24 hours.
The organic phase was then separated, dried over sodium sulfate. The product was filtered under
reduced pressure [Sebastien Queste et al, 2006].
Scheme-2 Synthesis of non-ionic Gemini surfactant from glycerol ester and 1, 6 -
Dibromohexane.
3414.12
2928.04
2857.64
2353.23
2126.59
1734.06
1639.55
1568.18
1545.03
1459.20
1245.09
1181.44
1109.11
1050.28
922.00
867.03
715.61
668.36
474.50
4000 3500 3000 2500 2000 1750 1500 1250 1000 750 500
64
3. RESULTS AND DISCUSSION
3.1 Characterization
3.1.1 FTIR- IR spectra of Gemini surfactant is given in fig. 1. It shows absorption band at 1734 cm-1
(C=O stretching), 2928 cm-1and 2857 cm-1 (C-H asymmetric and symmetric stretching in methylene
and methyl group), 1459cm-1 (C-H bending streching), 1109-1050cm-1 (C-O stretching in C-O of
ether), 3414 cm-1 (OH- symmetric stretching), 715 cm-1 for -(CH2)n- skeletal present in synthesized
compound [B. S. Furniss et al, 1989].
Fig. 1: FTIR spectra of synthesized Non-ionic Gemini Surfactant
1/cm
52.5
%T
45
37.5
30
22.5
15
7.5
0
3.1.2 1H-NMR- The 1H-NMR spectra of Gemini surfactant assigned for observed peaks is shown in
fig. 2. The shift at 0.9 ppm and 1.3 ppm are due to the presence of methyl (CH3) and methylene
(CH2) group in synthesized compound respectively. The multiplet accruing at 3.7 ppm to 3.4 ppm
may be due to the ether group i.e. CH2-O-C group present in the synthesized compound. The proton
with -value at 1.5 ppm is due to the CH- proton present in the compound. The proton with -value
at 5.5 ppm is due to the proton attached to oxygen atom i.e. presence of the hydroxyl group (OH) in
the synthesized compound. The -value at 2.1 ppm is due to the ester group i.e. CH-CO-OR [B. S.
Furniss et al (1989)]. Some extra peaks were obtained. They resulted not only from the synthesized
compound but also from the other byproduct and unreacted compounds.

4. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
1.4363
1.4546
1.4729
1.4910
1.5568
1.5733
1.5787
1.5904
1.6007
1.6070
1.6482
1.6679
1.6869
1.9446
2.0509
2.0667
2.0828
2.1797
2.1982
2.2176
2.7882
3.2074
3.2284
3.2474
3.5598
3.5762
3.5892
3.6055
3.6126
3.6292
3.6457
3.6562
3.6673
3.6855
3.6966
3.8055
3.9666
4.7639
4.7798
4.8306
4.8923
4.9300
5.3138
5.3420
5.3560
5.3841
5.4003
3.00
2.75
19.40
5.29
4.60
1.02
1.67
2.52
2.12
GSB-1
11 10 9 8 7 6 5 4 3 2 1 0 ppm
GSB-1 BRUKER
13.23
13.83
19.38
22.52
22.63
23.46
24.88
25.55
26.44
27.06
27.38
29.35
29.69
29.90
31.32
31.47
31.96
37.99
58.39
61.68
62.55
72.12
127.49
127.98
129.18
129.62
130.15
182.47
210 200 190 180 170 160 150 140 130 120 110 100 90 80 70 60 50 40 30 20 10 ppm
65
BRUKER
AVANCE II 400 NMR
Spectrometer
SAIF
Panjab University
Chandigarh
Current Data Parameters
NAME Nov25-2013
EXPNO 320
PROCNO 1
F2 - Acquisition Parameters
Date_ 20131126
Time 6.05
INSTRUM spect
PROBHD 5 mm PABBO BB-PULPROG
zg30
TD 65536
SOLVENT D2O
NS 16
DS 2
SWH 12019.230 Hz
FIDRES 0.183399 Hz
AQ 2.7263477 sec
RG 45.2
DW 41.600 usec
DE 6.00 usec
TE 296.9 K
D1 1.00000000 sec
TD0 1
======== CHANNEL f1 ========
NUC1 1H
P1 10.90 usec
PL1 -3.00 dB
SFO1 400.1324710 MHz
F2 - Processing parameters
SI 32768
SF 400.1299503 MHz
WDW EM
SSB 0
LB 0.30 Hz
GB 0
PC 1.00
avtar_saifpu@yahoo.co.in
Fig. 2: 1H-NMR spectra of synthesized Non-ionic Gemini Surfactant
3.1.3 13C-NMR- The 13C-NMR spectra of Gemini surfactant obtained for the observed peaks is
shown in fig.3. The chemical shift at 182 ppm may be assigned to the C=O of ester. The various
peaks at 13-50 ppm are due to the presence of methyl and methylene group in synthesized
compound. The chemical shift at 62 ppm may be assigned to the RCH2OR i.e. ether group present in
the compound. The peak accruing at 72 ppm is due to the presence of CH-OH moiety in the
compound. The presence of unsaturated alkyl chains are evident from the line at 130-131 ppm [L. M.
Harwood et al, 2011].
AVANCE II 400 NMR
Spectrometer
SAIF
Panjab University
Chandigarh
Current Data Parameters
NAME Nov25-2013
EXPNO 322
PROCNO 1
F2 - Acquisition Parameters
Date_ 20131126
Time 6.38
INSTRUM spect
PROBHD 5 mm PABBO BB-PULPROG
zgpg30
TD 65536
SOLVENT D2O
NS 512
DS 4
SWH 24038.461 Hz
FIDRES 0.366798 Hz
AQ 1.3631988 sec
RG 2050
DW 20.800 usec
DE 6.00 usec
TE 297.3 K
D1 2.00000000 sec
d11 0.03000000 sec
DELTA 1.89999998 sec
TD0 1
======== CHANNEL f1 ========
NUC1 13C
P1 9.60 usec
PL1 -2.00 dB
SFO1 100.6228298 MHz
======== CHANNEL f2 ========
CPDPRG2 waltz16
NUC2 1H
PCPD2 80.00 usec
PL2 -3.00 dB
PL12 14.31 dB
PL13 18.00 dB
SFO2 400.1316005 MHz
F2 - Processing parameters
SI 32768
SF 100.6127690 MHz
WDW EM
SSB 0
LB 1.00 Hz
GB 0
PC 1.40
avtar_saifpu@yahoo.co.in
Fig. 3: 13C-NMR spectra of synthesized Non-ionic Gemini Surfactant
3.2 Physicochemical Properties
3.2.1 Surface Activity-Surfactant form aggregates of molecules called micelles, which are formed
when the concentration of surfactant solute in the bulk of the solution exceed a limiting value, called
critical micelle concentration (CMC), which is the fundamental characteristic of each solute-solvent
system. If the interfacial property of a surfactant solution is plotted as a function of the concentration
of the solution, the interfacial properties is vary linearly with the concentration up to the CMC, at
which point there is a break in the curve as shown in Fig. 4.
The surface tension of water (72 mN/m at 25OC) is normally reduced to a value 30-40
mN/m at the cmc of surfactant. Gemini surfactant is generally superior over conventional surfactant
in term of surface activity. This is due to the distortion of water by hydrophobic groups. In Gemini
surfactant two hydrophobic groups in single molecules are more disruptive than individual chain in
conventional surfactant.

5. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
66
Fig. 4: Variation of surface tension versus log conc. at 25OC
Effectiveness is determined by the difference between interfacial tension values at CMC
(CMC) and the interfacial tension values measured for pure water at the appropriate temperature (0).
The most effective surfactant gives the greatest lowering of surface tension for given CMC. The
values of surface tension at CMC, critical micelles concentration and effectiveness are shown in
table 1.
Table 1: Surface active properties of the Gemini surfactant at temp (25oC)
Sr. No. Parameters Values
1 Surface Tension 30.1 mN/m
2 Critical Micelle concentration 0.0007 mMolL-1
3 Effectiveness (cmc) 41.9 mN/m
3.2.2 Performance Properties- Among the performance properties emulsifying power, wetting
power, foaming power and stability, dispersion capability of product at different concentrations have
been studied and results are shown in table 2.
3.2.2.1 Emulsifying power- Emulsifying power of the aqueous solutions of product was determined
for water/liquid paraffin (light) system. Stable emulsion was formed using surfactant solution to oil
in a ratio of 1:1 (volume:volume). At different concentration of the synthesized Gemini surfactant, a
creamy emulsion of oil in water was observed. The more is the time required for clearing the two
layers, the higher is the emulsifying power of the surfactant [Xu RF et al, 2012]. On storage during
the steady state, it was observed that the creamy stability gradually decreases. This may be result of
droplet break and not droplet formation. The emulsifying power of surfactant increases with
concentrations as shown in table 2.
3.2.2.2 Wetting Performance-The wetting behaviors of the product synthesized was studied using
the canvas disc method [McCutecheon JW 1950]. The time required to sink the canvas disc in
surfactant solution was measured as wetting time. The minimum is the time required for sinking the
disc, higher is the wetting power of surfactant. The wetting time decreases with increase in
concentration as shown in table 2. The result shows that wetting performance of synthesized Gemini
surfactant is much better even at low concentration.
3.2.2.3 Foaming power and stability-The most widely appreciated property of surface active
substances in aqueous solution is their ability to promote the formation of foam and bubbles. These
behaviors could be attributed to the physical nature and bubble formation [S. Warwel et al, 2004].

6. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
The results obtained for synthesized Gemini surfactant shows high quality foam production. The
foam produced from synthesized surfactant has thicker nature with small bubbles throughout the
experimental period. The foaming power and stability increases with increase in concentration of
synthesized product (table 2).
67
Table 2: Emulsifying power, wetting time, foaming power, foaming stability of synthesized Gemini
surfactant at different concentration
Sr.
No.
Concentration
of surfactant
(0.1gm/100ml)
Emulsifying
power
(minute)
Wetting
time
(second)
Foam
volume(ml) at
30 second
Foam
volume(ml) at
300 seconds
1 0.1 5 22 121 73
2 0.2 8 16 164 110
3 0.3 14 13 18 1 133
3.2.2.4 Dispersing capability [Zhu YP et al, 1990]-A surfactant possesses the ability to disperse the
agglomerative solid particle, and this is called dispersibility. Generally, dispersibility is measured by
its lime-soap dispersion ability. The lime soap dispersion capability of the synthesized gemini
surfactant was measured as 28%. The smaller the LSDR %, the better is the dispersibility. It was
found that the dispersion capability of synthesized surfactant is quite good.
3.3 Contact Angle Measurement [Erwin A. Vogler et al, 1992]-The dynamic contact angles of
Glass slides, Steel slides, Teflon slides against diluted surfactant solution (0.1M) were determined as
shown in table 3. These values of contact angle were lower than those obtained for pure water.
Smaller the contact angle better is the wetting power. These value show that synthesized Gemini
surfactant has very good wetting property.
Table 3: Contact angle values of 0.1M synthesized Gemini surfactant with respect to different solid
probes
Sr. No. Solid probes Contact angle With respect to
Distilled water Surfactant sol (0.1M )
1 Glass 300 70
2 Steel 750 180
3 Teflon 980 400
3.4 Solubilization Behaviour: A light-scattering technique was used to measure the solubilizing
power of the prepared surfactant solutions at 28OC using Hatch model 1/100 turbidity meter.
Solubilizing power of different surfactant solutions was measured by dispersing paraffin oil as a non-polar
solute and 1-Heptanol as a polar solute. 1 gm of solute was mixed together with 100 ml of
surfactant solution (0.5%) using rotary shaker at 240 rpm for different time interval (0, 2, 5, 10, 20,
30, 40, 50 and 60 minute) and turbidity was measured.
Solubilization behavior of aqueous solution of non-ionic Gemini surfactant is represented
in fig.5 (a) and (b) for different type of solutes (heptanol and paraffin oil as polar and non-polar
solute respectively) at 28OC. These figures show that the turbidity of the surfactant solutions was low
at the beginning of the experiment (T= 0) but the turbidity of the system gradually increases with

7. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
shaking time. The solubilizing process depends on many variables, especially the nature of the
solvent, alkyl chain length, head groups, concentration of solvent in solution and chemical structure
of the solute.
3.4.1 Surfactant/paraffin oil system- Solubilizing power of synthesized Gemini surfactant for
paraffin oil system is quite good as shown in fig.5 (a). This can be attributed to the fact that the
amount of material solubilized increased with an increase in the size of the micelles. Hence any
factor that causes an increase in either the diameter of the micelle or its aggregation number result in
the increase of solubilization.
3.4.2 Surfactant/Heptanol solubilizing system- The solubilization behavior for the
surfactant/heptanol system is shown in the fig. 5 (b). This solubilization behavior for the
surfactant/heptanol system poorer than the behavior of the surfactant/paraffin oil system. This poor
solubilization behavior indicates that emulsification is not the only interaction that took place
between system components, but some other factor influence the solubilization process. This factor
could have been an interaction between the two polar head in the different molecules [A. S.
Mohamed et al, 2004].
68
Fig.5: (a) and (b) Solubilization behavior of the Non-polar (light Paraffin oil) and polar
(Heptanol) solute respectively in an aqueous surfactant solution (0.5%) at 28OC
4. CONCLUSION
In the present study a new protocol for the synthesis of novel glycerol based non-ionic
Gemini surfactant through an environmental friendly process have been described. Glycerol based
nonionic Gemini surfactant has been successfully synthesized by using, 1, 6-dibromohexane as
spacer. The compound is characterized by FTIR, 1H-NMR and 13C-NMR spectroscopy. The surface
active properties like surface tension, critical micelle concentration, effectiveness have also been
studied. The performance properties like emulsifying power, foaming power and stability, dispersion
capability, wetting power, contact angle, solubilizing behaviour were also studied. It can be
concluded that the new glycerol-based non-ionic Gemini surfactant exhibit generally good
solubilizing and wetting behaviour. It appears to be a promising and valuable non-ionic surfactant. It
can be used as an emulsifier, wetting agent and foaming agent.

8. International Journal of Advanced Research in Engineering and Technology (IJARET), ISSN 0976 –
6480(Print), ISSN 0976 – 6499(Online) Volume 5, Issue 8, August (2014), pp. 62-69 © IAEME
69
ACKNOWLEDGMENT
Authors are thankful to the UGC (University Grants Commission of India), for providing
the research grant for this research work [Project F.No.41-373/2012 (SR)].
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