microwave synthesis of cationic fatty imidazolines and their characterization

ORIGINAL ARTICLE

Microwave Synthesis of Cationic Fatty Imidazolinesand their Characterization

Divya Bajpai Æ V. K. Tyagi

Received: 24 May 2007 / Accepted: 28 November 2007 / Published online: 15 January 2008

� AOCS 2008

Abstract This paper describes an efficient method for the

synthesis of long chain dialkyldiamido imidazolines by the

reaction of diethylenetriamine and several fatty acids under

non-solvent microwave irradiation using calcium oxide as

support This synthesis required much less time in com-

parison to conventional thermal condensation and is carried

out in an open vessel and the products obtained by this

method were found to be in good yields and of high purity.

Fatty imidazolines were then quaternized by using dime-

thyl sulfate as a quaternizing agent and isopropanol as a

solvent, to produce cationic imidazolinium salts which

were evaluated for yield and cationic content. The instru-

mental techniques, viz. FT-IR and 1H NMR verified the

formation of imidazolines and its subsequent quaterniza-

tion. This method produced imidazolines in the very low

time of 5–10 min and gave a yield of 89–91% as compared

to a very long time of 8–10 h and a lower yield of 75–80%

by the conventional thermal condensation method.

Keywords Microwave � Imidazolines �Non-solvent synthesis � Cyclization

Introduction

Long chain substituted imidazolines and their quaternized

products are of great importance because of their numerous

and varied industrial applications. Fatty imidazolines and

quaternized imidazolinium salts are frequently used as

fabric softeners [1], dispersants [2], anti-static agents [3],

bleach activators [4], and emulsifiers [5] not only because

of their good performance but also for their mildness to

eyes, skin and clothes [6] and their biodegradability [7]. In

addition, imidazolines compounds are gaining importance

in the paint and lubricant industries because of their cor-

rosion inhibition properties [8].

The 2-substituted imidazolines and their derivatives

exhibit a wide variety of biological activities including

anti-percholesterolemic, anti-inflammatory, anti-diabetic

and anti-hypertensive properties [9]. Imidazolines are also

used as insecticidal agents and disinfectants [10] in agri-

cultural sprays. These compounds are also used as

intermediates and catalysts [9] in synthetic chemistry.

Several methods for the synthesis of 2-imidazolines

from fatty acids, esters, nitriles, orthoesters, hydroximoyl

chlorides, hydroxyl amides and mono- or disubstituted

chlorodicyano vinyl benzene have been reported previ-

ously. General methods of preparation of imidazolines

involve dehydration between fatty acids and polyamines

under vacuum (Scheme 1). The fatty acids generally used

are stearic acid, palmitic acid, lauric acid, oleic acid and

some oils such as corn oil and rice bran oil. Polyamines

used are ethylenediamine (EDA), diethylenetriamine

(DETA), ethylene triamine tetra acetic acid (EDTA),

aminoethyl ethanolamine. This conventional thermal

method suffers from disadvantages such as long times, low

yield of the products and tedious work up [10, 11].

Nowadays, use of microwave irradiation in organic

synthesis is gaining special attention due to the generally

low reaction time, better yield and high purity of products

[12]. Especially dry reactions coupled with microwave

have received considerable interest as they minimize safety

problems.

D. Bajpai (&) � V. K. Tyagi

Department of Oil and Paint Technology,

Harcourt Butler Technological Institute,

Kanpur 208002, India

e-mail: [email protected]; [email protected]

123

J Surfact Deterg (2008) 11:79–87

DOI 10.1007/s11743-007-1057-z

This paper describes the microwave synthesis of 2-

heptadecyl-1-[2-(octadecanoylamino)ethyl]-2-imidazoline,

2-pentadecyl-1-[2-(hexadecanoylamino)ethyl]-2-imidazoline,

2-propdecyl-1-[2-(tetradecanoylamino)ethyl]-2-imidazoline

and 2-methdecyl-1-[2-(dodecanoylamino)ethyl]-2-imidazo-

line by the condensation of diethylenetriamine and fatty

acids (stearic acid, palmitic acid, myristic acid and lauric

acid) in solvent free conditions, using calcium oxide as the

substrate and their quaternization (Scheme 2) by using

dimethyl sulfate as the quaternizing agent.

Materials and Methods

Materials for synthesis of imidazolines: Chemicals used for

the synthesis of imidazolines and their quaternized salts

were of analytical grade obtained from M/s Qualigens and

E. Merck, Mumbai.

Experimental

Characterization of Raw Materials

The acid values (AV) and saponification values (SV) of

experimental fatty acids were determined according to the

BIS method (Table 1). Refractive index of diethylene tri-

amine (DETA)gD was 1.4826

Preparation of Imidazolines

In an open Pyrex vessel (500 mL) 2.06 g (20 mmol) of

diethylenetriamine, 40 mmol of the corresponding fatty

acid (stearic, palmitic, myristic or lauric, acid) and 20 g of

calcium oxide were carefully mixed. The reaction mixture

was irradiated using a power of 850 W in a microwave

oven for the required time (as given in Table 2) and the

final temperature was noted. The reaction mixture was

allowed to reach room temperature. Ethyl acetate was

added (80 mL) and the mixture was heated until boiling

and filtered off while hot, and the filtrate was concentrated

under vacuum to dryness, yielding the corresponding

product as a white to yellowish brown, solid to semisolid

substance (Table 2).

Preparation of Quaternary Imidazolinium Salts

Imidazoline (3.6 g) in 120 g of isopropanol was used and

1.5 mol of dimethyl sulfate was added to the solution and

the reaction mixture was refluxed at 80 �C with constant

H2NNH NH2 +

RO

OH

O

R NH

NH

NH

O

R

N NNH

O

RR

Diethylenetriamine Fatty acid

Fatty imidazolines

Diamido amine

Scheme 1 Synthesis of fatty imidazolines

NNH

O

RR

+ (CH3)2 SO4

Fatty imidazolines Dimethyl sulfate

CH3SO4-

Quaternized fatty imidazolines

R

N

N

N

O

R

+

N

Scheme 2 Quaternization of fatty imidazolines

Table 1 Characterization of raw materials

Fatty acids Acid value Saponification value

Stearic acid 196.3 196.0

Palmitic acid 218.5 218.4

Myristic acid 244.7 244.4

Lauric acid 279.5 279.2

80 J Surfact Deterg (2008) 11:79–87

123

stirring for 4 h, and then cooled to room temperature and

dried to recover the imidazolinium salts (Table 3).

Determination of Surface Active Properties of

Synthesized Quaternary Imidazolinium Salts (Table 9)

Materials and Methods

• 1% aqueous solutions of synthesized imidazolinium

surfactants based on C12–C18 saturated fatty acids.

Solubility

• Imidazolinium salts of saturated fatty acids of C14 and

C12 are soluble in polar solvents and their polarity

increases with a decrease in the carbon length of the

hydrophobic chain.

• Imidazolinium salts based on C16 and C18 saturated

fatty acids are less soluble in water and 10% alcohol v/v

was added to make their aqueous solutions.

Surface Tension and CMC (Critical Micelle

Concentration)

Surface tension and CMC of surfactants solutions were

determined at 25 �C with the help of a DCAT tensiometer.

Dispersing Power

To measure the dispersing power, carbon black and TiO2

were added separately to 1% surfactant solutions and the

mixtures were shaken and allowed to stand. Evaluations

were carried out by looking at the height and cloudiness of

each solution and noting the score.

Emulsion Stability

Emulsion stability was determined using 10 mL of

20 mmol aqueous solution of surfactants and 5 mL of tol-

uene at 40 �C. The emulsion stability was determined as the

time of separation of water (9 mL) from the emulsion layer.

Analysis

Procedure for Determination Total Amine Value [13]

The sample, if it is not already liquid, was melted in a

water bath, mixed thoroughly, and accurately 1–4 g

weighed into a 250-mL flask. Fifty millilitres of alcohol

was added and boiled for 1 min to drive off any free

ammonia that may have been present. This was then cooled

to room temperature. Five drops of bromophenol blue

indicator were added and it was then titrated, while

swirling, with 0.2 N HCI to the yellow end point (Table 4).

Table 2 Synthesis of fatty imidazolines using different fatty acids under microwave conditions

S. No. Fatty acid (g) Polyamine (g) Molar ratio of

fatty acid and

polyamine

Power of

microwave

oven used (W)

Reaction time

(min)

Final temperature

(�C) approx.

Yield (%)

1 Stearic acid (11.4) Diethylene-triamine (2.06) 2:1 850 8.0 215 91.7

2 Palmitic acid (10.2) Diethylenetriamine (2.06) 2:1 850 7.0 200 90.8

3 Myristic acid (9.1) Diethylenetriamine (2.06) 2:1 850 7.0 200 90.2

4 Lauric acid (8.0) Diethylenetriamine (2.06) 2:1 850 6.0 191 89.8

Table 3 Preparation of quaternary imidazolinium salts

S. No. Imidazoline type Weight of

imidazoline

(g)

Dimethyl

sulphate

(g)

Iso-propa-

nol

(g)

Time

(h)

Temperature

(�C)

Yield

(%)

1 2-heptadecyl-1-[2-(octadecanoylamino)ethyl]-2-

imidazoline

3.6 1.5 120 4 80.0 80.9

2 2-pentadecyl-1-[2-(hexadecanoylamino)ethyl]-2-

imidazoline

3.4 1.5 120 4 80.0 81.2

3 2-prop decyl-1-[2-(tetradecanoylamino)ethyl]-2-

imidazoline

3.1 1.5 120 4 80.0 81.4

4 2-meth decyl-1-[2-(dodecanoylamino) ethyl]-2-imidazoline 2.7 1.5 120 4 80.0 82.2

J Surfact Deterg (2008) 11:79–87 81

123

Calculation

The total amine value was calculated as follows

Total amine value meq=gð Þ ¼ V � N

S

where V = HCI required for titration of the specimen;

N = Normality of the HCI solution; S = Specimen weight

of sample.

Determination of Cationic Matter [14]

Reagents

(i) Chloroform

(ii) Standard sodium lauryl sulfate solution (0.004 M)

(iii) Standard benzethonium chloride solution (Hyamine

solution) (0.004 M)

(iii) Methylene blue solution (0.005%)

(iv) Solution of Imidazolinium salt (0.004 M)

Procedure

Standardization of sodium lauryl sulfate solution: Stan-

dardization of sodium lauryl sulfate solution was done by

using 0.004 M solution of benzethonium chloride solution

and calculated as follows:

Molarity of SLS T2ð Þ ¼10 T1

V1

where T1 = molarity of hyamine solution; V1 = volume of

SLS solution added.

Determination of cationic content (Table 5): An amount

of 10 mL of standard sodium lauryl sulfate solution was

pipetted into a 100-mL graduated cylinder provided with a

glass stopper. Then 15 mL of chloroform and 25 mL of

methylene blue solution were added to the cylinder and

shaken well. From a burette imidazoline solution was

added slowly, initially in portions of 0.2 mL. After each

addition, the cylinder was stoppered and shaken well to

allow the phase to separate. The reading at which the color

intensity in both the phases is the same when viewed under

standard conditions of light was noted.

Molarity of imidazoline; T3 ¼ 10 T2=V2

where T2 = molarity of SLS; V2 = volume of imidazoline

solution.

Cationic matter %

¼ T3 �molecular weight of imidazoline � 100

Weight of sample present in 250 ml� 4

Characterization of fatty imidazolines and their salts:

Acid values of the product were found to be less than 5,

which showed the maximum conversion of fatty acid

into the product. Quaternary imidazolinium salts were

characterized by their cationic content. Structural

confirmation of products was done by using 1H-NMR

and IR spectroscopy (Table 6). FT-IR spectra of

imidazolines and quaternary imidazolines were obtained

by using an FT-IR spectrometer. KBr pellets of the sample

were subjected to analysis at 20 scans. 1H NMR of the

same imidazoline and quaternary imidazolines were carried

out by an FT-NMR system of A Lambda JEOL JNM-

LA400. Chemical shifts are reported as (ppm) relative to

tetramethyl silane.

Results and Discussion

Effect of the Molar Ratio of Fatty Acid

and Diethylenetriamine on the Synthesis

of Imidazolines (Table 7)

In the present research work, syntheses of imidazolines

were carried out at different molar ratios of 2:0.5, 2:0.75,

Table 5 Cationic content of imidazolinium salts

Name of quaternary imidazoline Cationic

content

(%)

2-heptadecyl-1-[2-(octadecanoylamino)ethyl]-2-

imidazolinium methyl sulphate

57.4

2-pentadecyl-1-[2-(hexadecanoylamino)ethyl]-2-


59.8

2-propdecyl-1-[2-(tetradecanoylamino)ethyl]-2-


62.8

2-methdecyl-1-[2-(dodecanoylamino)ethyl]-2-


67.4

Table 4 Total amine value of different imidazolines

Name of imidazoline Amine

content

(meq/g)

2-heptadecyl-1-[2-(octadecanoylamino)ethyl]-2-

imidazoline

0.9

2-pentadecyl-1-[2-(hexadecanoylamino)ethyl]-2-

imidazoline

0.9

2-propdecyl-1-[2-(tetradecanoylamino)ethyl]-2-

imidazoline

1.1

2-methyldecyl-1-[2-(dodecanoylamino)ethyl]-2-

imidazoline

1.0


123

2:1 and 2:1.5 of fatty acids and amines at constant power

(850 W) for constant reaction times and the percentage

yields were calculated. In the case of stearic acid, a

2:0.5 M ratio of reactants gave a yield of 46.6% at 850 W

power and an 8-min reaction time. By increasing the ratio

of DETA from 2:0.5 to 2:1, a remarkable increase in the

percentage yield from 46.6% to 91.7% was noticed. Further

increasing the ratio of stearic acid and DETA from 2:1 to

2:1.5 showed a negligible change in the percentage yield of

the product. An almost identical pattern was observed in

the case of all other fatty acids under question; viz., pal-

mitic acid, myristic acid and lauric acid (Table 2).

A molar ratio of 2:1 resulted in maximum yield of im-

idazolines which also supports the stoichiometry of

reaction (i.e. 2 mol of fatty acid react with 1 mol of DETA

to produce 1 mol of imidazoline). The percentage yield of

the molar ratio 2:0.5 again supported the same fact, in

which 0.5 mol of DETA only reacted with 1 mol of fatty

acid, hence gave a percentage yield approximately half that

of the percentage yield at the molar ratio of 2:1. An

increase in the molar ratio from 2:1 to 2:1.5 resulted in

approximately the same yield as at the molar ratio of 2:1,

indicating that 1 mol of DETA is sufficient for the

consumption of 2 mol of fatty acid. Hence 2:1 M ratio of

fatty acid and DETA was found to be optimum for the

synthesis of imidazolines.

Table 6 Spectral analysis of synthesized fatty imidazolines and their salts

Compound FT-IR (KBr) 1H-NMR (d values) 1C-NMR (d values)

2-heptadecyl-1-[2-

(octadecanoylamino)ethyl]-2-

imidazoline

CH3 C–H stretching

2,951 cm-1,

(CH2)16 skeletal

719 cm-1,

N–H stretching

(secondary amine)

3,435 cm-1,

–C=O stretching

(amide) 1,734 cm-1,

C=N stretching

1,655 cm-1

(imidazoline ring)

CH3 (0.86 ppm, 0.87 ppm, 0.89 ppm),

(CH2)n (1.25 ppm),

CH2 attached to nitrogen of imidazoline

ring (2.66 ppm, 2.75 ppm, 2.80 ppm),

CH2 attached to carbon of imidazoline

ring (2.36 ppm, 2.37 ppm, 2.39 ppm),

CH2 attached to carbon of amide group

1.5 ppm, 1.6 ppm, 1.7 ppm),

CH2 attached to nitrogen of amide

group 2.1 ppm,

–CONH– 6.1 ppm,

equivalent ring methylene group

(3.34 ppm, 3.64 ppm).

C2 of imidazoline ring 118.8 ppm,

Equivalent ring of methylene

carbon

49.4 ppm,

Equivalent methylene carbon

33.1 ppm,

NHCOR 127.32 ppm, (CH2)

29.5 ppm.

2-heptadecyl-1-[2-

(octadecanoylamino)ethyl]-2-


CH3 C–H stretching

2,918 cm-1,

(CH2)16 skeletal

731 cm-1,

N–H stretching

(secondary amine)

3,441 cm-1,

–C=O stretching

(amide) 1,734 cm-1,

C=N stretching

1,655 cm-1

(imidazoline ring),

S=O stretching

1,460 cm-1 (CH3SO4).

CH3 (0.86 ppm, 0.87 ppm, 0.89 ppm),

(CH2)n (1.25 ppm),

CH2 attached to nitrogen of imidazoline

ring (2.66 ppm, 2.75 ppm, 2.80 ppm),

CH2 attached to carbon of imidazoline

ring (2.36 ppm, 2.37 ppm, 2.39 ppm),

CH2 attached to carbon of amide group

1.5 ppm, 1.6 ppm, 1.7 ppm),

CH2 attached to nitrogen of amide

group 2.1 ppm,

–CONH– 6.1 ppm,

Equivalent ring methylene group

(3.34 ppm, 3.64 ppm),

CH3SO4 (7.25 ppm).

C2 of imidazoline ring 125 ppm,

Equivalent ring of methylene

carbon

45.13,

Equivalent methylene carbon 32.6

ppm,

NHCOR 131.2 ppm, (CH2) 29.48,

CH3SO4- methylene carbon 48.2.

Table 7 Effect of the molar ratio of fatty acid and DETA on the

synthesis of imidazolines at constant power and constant molar ratio

S. No. Fatty acid Time (min) Molar ratio

Fatty acid:DETA

% Yield

1 Stearic acid 8 2:0.5 46.6

2:1 91.7

2:1.5 91.5

2 Palmitic acid 7 2:0.5 44.7

2:1 90.8

2:1.5 90.6

3 Myristic acid 7 2:0.5 43.9

2:1 90.2

2:1.5 90.3

4 Lauric acid 6 2:0.5 43.2

2:1 89.8

2:1.5 89.6

Power = 850 W


123

Effect of Time on the Synthesis of Imidazolines

at Constant Molar Ratio and Power

The effect of time was studied at a constant molar ratio

(2:1) and constant power (850 W). In the case of stearic

acid, the reaction was carried out at a constant molar ratio

of 2:1 and a constant power of 850 for different reaction

times, viz.; 7, 8 and 9 min and the results are depicted in

Table 8. For a 7-min reaction time, the final temperature

recorded was 200 �C which resulted in very much lower

yield of imidazolines. For 8 min, the final temperature was

210 �C and the percentage yield of imidazolines was

91.7%. A further increase in reaction time from 8 to 9 min

resulted in a decrease in the yield of imidazolines due to

charring of some of the reactants at the high temperature of

228 �C. These results show that the reaction time of 7 min

was insufficient to attain the temperature of 210 �C

required for complete conversion of reactants to imidazo-

lines. A reaction time of 8 min resulted in the formation of

imidazolines in good yield indicating that in this reaction

time, the reaction mixture reached a temperature of 210 �C,

which is required for cyclization. A further increase in time

up to 9 min increased the temperature of the microwave

oven up to 228 �C resulting in overheating of some of the

reactants.

For palmitic acid and myristic acid, reactions were

carried out at 6, 7 and 8 min, respectively, and the final

temperatures recorded were 191, 200 and 210 �C. A

reaction time of 6 min showed very low yield of imidaz-

olines formed, as 191 �C was not sufficient for complete

conversion of the reactants to the product. An increase in

the reaction time to 7 min gave a good yield of products

and a further increase in time to 8 min caused charring of

some of the reaction mixture. For lauric acid, reaction time

of 5 min gave a good yield of the product. Further

increases in reaction time caused charring of some of the

reactants and a decrease in reaction time also resulted in a

low yield.

These results showed that, for constant molar ratio and

constant power, 8 min of reaction time was optimal for

stearic acid, 7 min was optimal for palmitic acid and

myristic acid and 6 min reaction time was optimal in the

case of lauric acid. Cyclization of diamidoamine of stearic

acid required a longer reaction time than any other fatty

acid because the stearyl group has a chain length longer

than any other fatty alkyl group used in the present research

work. Similarly, lauric acid has the lowest number of

carbon atoms in the alkyl chain hence required a lower

reaction time. The greater the length of the alkyl chain, the

higher the temperature required, hence a longer reaction

time.

Spectral Analysis (Figs. 1–4)

Imidazoline and quaternary imidazoline were characterized

by FT-IR and 1H NMR. Our interpretation was confirmed by

nuclear magnetic resonance (NMR). The instrumental

analysis of imidazoline and quaternary imidazoline con-

firmed the proposed chemical structure of imidazoline and

quaternary imidazoline. The formation of imidazoline was

confirmed by the FT-IR results indicating CH3, CH- str. at

2951.35 cm-1; (CH2)n skeletal at 719.51 cm-1; NH2, N–H

stretching at 3427 cm-1 ; N–H deformation at 1458.32 cm-1;

stretching C–N at 1238.41 cm-1 (amide group); stretching

C=O (amide group) at 1655.07 cm-1; –S=O– stretching at

1091 cm-1.

In 1H-NMR spectra of compounds, peaks at 3.0–

3.6 ppm showed the formation of an imidazoline ring. The

presence of an amide group was confirmed by the presence

of peaks at 6.0–7.0 ppm. Quaternization was confirmed by

the presence of peaks at 7.2 ppm.

Surface Tension

In the case of C12–C18 saturated fatty alkyl lipophilic

groups, the surface tension of a 1% aqueous solution of

imidazolinium salts decreases with the decrease in the

chain length of the lipophilic group. The oleic acid deriv-

ative showed a lower surface tension than its saturated

homologue due to the presence of a double bond while a

palm fatty acid based surfactant solution and a non-ionic

surfactant showed almost similar surface tension.

Table 8 The effect of time on the synthesis of imidazolines at con-

stant power and constant molar ratio

S. No. Fatty acid Time (min) % Yield

1 Stearic acid 7 56.8

8 91.7

9 90.2

2 Palmitic acid 6 41.8

7 90.8

8 89.8

3 Myristic acid 6 40.9

7 90.2

8 88.2

4 Lauric acid 5 40.9

6 89.8

7 86.4

Molar ratio = Fatty acid:DETA = 2:1; Power = 850 W


123

Dispersing Power

Cationic surfactant solutions showed good dispersing

power. Increases in the chain length of the lipophilic

group gradually increases the dispersing power of

imidazolinium surfactants. A stearic acid-based imidazo-

linium surfactant showed the best dispersing power due to

the longest hydrophobic chain among four while the im-

idazolinium salt of lauric acid showed the worst

dispersing power.

Emulsion Stability

Cationic imidazolinium surfactants showed good emulsion

stability in comparison of non-ionics and anionics. In im-

idazolinium surfactants, an increase in the chain length of

the lipophilic group gradually increases the emulsion sta-

bility, following the order:

Stearic acid based imidazolinium salts

[ Palmitic acid based imidazolinium salts

[ Myristic acid based imidazolinium salts

[ Lauric acid based imidazolinium salts

Experimental results showed that the synthesis of fatty

imidazoline through microwave irradiation gives a better

yield in a few minutes which is very much shorter reaction

time in comparison to conventional methods. Classical

methods of imidazoline synthesis involve long reaction

times (8–10 h) and comparatively lower yields (85–87%).

Fig. 1 A 1H-NMR spectrum of

dialkyl amido imidazoline based

on stearic acid

Fig. 2 An FT-IR spectrum of dialkyl amido imidazoline based on

stearic acid


123

Microwave synthesis is an excellent methodology for the

synthesis of long chain dialkylamidoethyl imidazolines.

The procedure avoids the use of reduced pressures and long

reaction times as it is carried out in an open vessel and only

takes a few minutes for the synthesis of alkyl imidazolines,

which on quaternization give quaternary imidazolines.

Quaternary imidazolines are reported to be good fabric

softeners and anti-static agents and also show good

rewettability, dispersability and are useful for laundry

detergents as cationic–non-ionic detergent compositions

(Table 9).

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based on stearic acid

Fig. 4 An FT-IR spectrum of dialkyl amido imidazoline quat based

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Table 9 Surface active properties of synthesized imidazolinium salts

Properties S P M L

Surface tension dyne/cm2 at 28 �C 35.7 31.4 24.1 29.2

CMC 9 103 mol/L 0.22 0.24 0.26 0.27

Dispersing power (vol. in mL) 10 9 7 6

Emulsion stability (h) 3.45 3.20 3.00 2.50


123

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Author Biographies

Divya Bajpai is currently a Research Scholar at the Department of

Oil and Paint Technology of the Harcourt Butler Technology Institute

(HBTI) Kanpur (INDIA). Ms. Bajpai obtained her B.Sc. degree in

Chemistry in 2000 from PPN Post Graduate College, Kanpur

(C.S.J.M. University, Kanpur). She obtained her M.Sc. degree in

Organic Chemistry in 2002 from DAV Degree College, Kanpur

(C.S.J.M University, Kanpur).

V. K. Tyagi received his B.Tech. in Chemical Technology (Oil

Technology) in 1984, M.Tech. (Oil Technology) in 1986 and Ph.D.

(Oil Technology) in 1992 from HBTI, Kanpur (India). He has more

than 18 years experience in teaching UG & PG level & Research at

HBTI, Kanpur (India). Presently he is working as Professor (Paint

Technology) at HBTI, Kanpur. He has published more than 34 papers

in national and international journals, and presented 18 papers in

national and international seminars/conferences.


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microwave synthesis of cationic fatty imidazolines and their characterization

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