1. No category

Malaysian Polymer Journal, Vol. 9 No. 2, p 62-66, 2014
Available online at www.cheme.utm.my/mpj
EFFECTS OF PALM OIL ON THE PROPERTIES OF LONG ALKYD AND
MEDIUM ALKYD RESINS
B.V. Itoua*1, D.S. Ogunniyi2, JE Moussounga1, P.R. Ongoka1
Département of Chemistry, Ecole Normale Supérieure B.P 237, Université Marien Ngouabi, Brazzaville-Congo
1
Department of Chemical Engineering, University of Ilorin, Ilorin. Kwara State, Nigeria.
2
*Corresponding author’s e-mail: [email protected], Tél: (00242) 05.766.52.12
Abstract: Two blends of palm oil and alkyd resins were prepared. The first blend comprises palm oil and longoil alkyd while the second blend comprises palm oil and medium alkyd resin. These blends contained
quantities of palm oil ranging from 10% to 50%. Also, a drying agent composed of a mixture of cobalt, calcium
and lead compounds was included in each blend sample. After the preparation of the samples, their physicochemical properties were obtained. The analysis showed that the blends exhibited low viscosity and density,
which indicated good rheological properties. The results suggest that palm-oil can be used as blending additive
with medium and long alkyd resin coating formulations. The drying times of both alkyd blends increase with
increase in palm oil content. However the increment of palm oil in the blend of long oil alkyd resin is moderate
up to 30% oil content and increases sharply at 40% oil content. Around 40% of palm oil, the drying time
extends to 24h. In the blend of palm oil with medium oil alkyd, the observation shows that the drying times
remained practically unchanged up to 20% oil content with the increment of palm oil. Around 30% of palm oil,
the drying times extends to 24h.
Keywords: Long alkyd resin; Medium alkyd resin,; palm oil; physical properties rheological properties.
1.
INTRODUCTION
Alkyd resins are widely used in the surface coatings
industry, in electronics and wood industries, graphic
arts, and many more [1]. They are relatively
inexpensive to produce, and can provide good
properties such as high gloss, good color retention and
good thermal stability. They are resinous materials
synthesized from the reactions of polyol, dicarboxylic
acid, and triglycerides or fatty acids derived from
vegetable oils [2]. The advantages of alkyds include
their versatility, good film performance, and fast
drying [3]. Also, alkyd resins are used extensively as
binder for making industrial and offshore paints; such
paints are usually exposed in tough conditions e.g.
exposure to UV-radiation, thermal fluctuations, high
humidity. Under these conditions, the paints shows
considerable chalking, colour fading and loss of gloss.
For enhancing the durability of such paints one
proceeds with some modifications of alkyd resins to
improve the film-forming properties. Blends of alkyd
resin with petroleum resin have been reported to give
good physico-chemical and mechanical properties [4].
Alkyds made with high amount of vegetable oil have
excellent gloss and wetting of pigments, whereas those
produced with lesser amount of vegetable oil have
better hardness and chemical resistance [5]. Different
oil lengths are used in the preparation of alkyds resins.
Medium and short alkyds have been prepared from
styrenated rubber seed oil alkyd [6,7]. Blends of long
and medium alkyd resins contribute to produce
intermediate and top coats with workable coating
properties [8].
Palm oil is a major edible oil in the world. It is
classified as non drying oil because of its low iodine
value; palm oil alkyds are not capable of forming
coherent film by air oxidation. Consequently, there are
very few reports of the use of palm oil alone in making
alkyds for coating application. Palm oil has been mixed
with tung oil to produce a workable coating resin [9]
while palm oil-based alkyd with epoxy resins are
reported to produce coating resin with good hardness
[10]. The introduction of sufficient unsaturated C-C
double bonds in some palm oil-based-alkyds caused
the reduction of the drying time of the alkyds [11].
Another paper reported the mixing of palm oil basedalkyds with melamine to form baking enamels [12].
Also, coating materials from non-drying palm oleic acid
was found to have high water and salt resistances [13].
Although unmodified palm oil-based alkyd have
difficulty in drying due to the relatively low iodine
value palm oil, contributes to produce a film with
excellent adhesion [14] and can be used as an additive
for enhanced rheological properties [15]. The use of
palm oil as an additive is available for both long and
medium alkyd resins. This paper describes the effects
of palm oil on the properties of long alkyd and
medium alkyd resins.
2.
2.1
EXPERIMENTAL
Materials
Palm oil was obtained from Ng. Enterprise (Ng
Enterprise, Edou, oyo District, republic of Congo).
Commercial long alkyd resin was produced by
MPCROKIM, 32, rue du mercure Z.I, Ben Arous 2013
Benarous, Tunisia and it was supplied by Congolese
Enterprise of paint (COPE). The commercial medium
alkyd and drier used were produced by DSM Coating
resin, Netherlands. The drier was a mixture of 10% of
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Itoua, B. V. et al. Malaysian Polymer Journal, Vol. 9, No. 2, p 62-66, 2014
zinc-based drier, 10% of calcium-based drier, 10% of
cobalt-based drier, and 10% of lead-based drier in white
spirit as solvent. All materials were used as received.
2.2
M: mass test specimen
Method
Alkyd resins (long and medium) were mixed intimately
with palm oil in a small aluminum box of 50ml using a
spatula as mixer. After near-perfect homogeneity of the
mixture, it was left for two hours for air bubbles in the
mixture to escape. Different samples with 10%, 20%,
30%, 40%, 50% palm oil were prepared. The same
quantity of driers (0,2%) was mixed with each sample.
2.3
Testing
2.3.1
Viscosity
2.3.6
Peroxide value
Peroxide value was determined using AOAC method
and according to standard 965.33,1977. Titration was
vigorously agitating the iodine released with the
thiosulfate solution.
The peroxide index (IP) is calculated as follows:
IP =
(𝑉−𝑉0)x 𝑁 x 100
𝑀
=
(𝑉−𝑉0)x 𝑁 x 100
𝑀
V: volume in ml of the thiosulfate solution used
The viscosity was measured by using Brookfield rotary
Viscometer KU-2 model DV-III according to ISO 288. It
is composed of a dial with digital display and keys for
the hand drive operation. The measurements were
taken by using spindle n°6 and were posted directly on
the numerical dial.
2.3.2
N: normality of the solution of KOH
Density
The density was determined according to NF en 1097-6.
The measurements were taken by using analytical scale
and Pycnometer S9611826. The pycnometer is a metal
container standardized with volume 100cm3. It was
equipped with a bored lid of a hole to evacuate the
bubbles of air and an excess of product. The density is
determined by the following relation:
D=
𝑀2−𝑀1
𝑉
D: density of the product
M1: weight of the pycnometer empty
V0: volume in ml of the thiosulfate solution used for
the white test
N: exact normality of the thiosulfate solution
M: mass test specimen
3.
RESULTS AND DISCUSSION
3.1
Effect of palm oil on density of alkyd resin
blends
As the amount of palm oil content increases, the
density of the alkyd resin/ palm oil blend decreases
(figure 1). The addition of palm oil to alkyds reduced
the density of the resulting blends. It is expected that
the density of the blends will fall between the density
of palm oil (0.89) and the density of alkyd resin (0.95
for long oil alkyd resin and 1 for medium oil alkyd).
One notes that the density for medium alkyd resin is
higher than of long alkyd.
M2: weight of the pycnometer filled with product
V: volume of the pycnometer
1.02
Dry extract
The quantity of dry extract was determined by using
cooking isotherm (123°C) according to ISO 3251. The
dry extract was calculated from the difference of the
plates, which were taken initially and linearlly. The
mean value of the three results was reported as the
percentage non-volatile matter.
2.3.4
Drying time
The drying time (set-to-touch time) was determined
according to ISO 9117. The measurements were taken
by using a painting applicator 150 microns. A
thickness of 150µm is applied on the contrast paper
and exposed for drying in free air. The drying time is
measured when the film was no more sticking to the
touch.
2.3.5
Acid value
Acid value was determined according AOAC method
and to standard 969.17 1997. The mixture was titrated
against the alkaline solution of KOH with a pale pink
coloruring. The acid value (IA) is calculated as follows.
IA =
𝑉 x 𝑁 x 56,1
𝑀
V: the volume of KOH (in ml) necessary to the
neutralization of the free fatty acids.
1.00
0.98
Density
2.3.3
0.96
0.94
0.92
0
10
20
30
40
50
60
Oil ( % )
medium alkyd resin
long alkyd resin
Figure 1: density curve of long and medium oil alkyd
resin with quantity of oil
3.2 Effect of palm oil on dry extract of alkyd resin
blends
The effect of palm oil on dry extract of the blends is
shown in figure 2. The two curves have the same trend
because of the similarity in the nature and chemical
composition of the two alkyd resins. The difference is
in the length of their carbon chain. This explains the
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Itoua, B. V. et al. Malaysian Polymer Journal, Vol. 9, No. 2, p 62-66, 2014
difference in the values of density, viscosity, dry
extract, time of drying of these two types of resin. The
amount of dry extract increases as the palm oil content
in both blends of alkyds increases. The palm oil blend
with long alkyd resin shows a higher dry extract. The
dry extract has a direct relationship with the molecular
weight of the alkyds [16], and the increase of dry
extract leads to the increment of their molecular
weight. In this observation the contribution of palm oil
to the increase of dry extract after drying should to the
increase on the thickness of the film [4].
90
85
75
70
65
6000
60
5000
55
4000
50
0
10
20
30
40
50
60
Oil ( % )
medium alkyd resin
long alkyd resin
Viscosity ( cps )
Dry extract ( %)
80
blend. The drying times in both blends increase with
the increase of palm oil content. The increment of
palm oil in the blend of long oil alkyd resin is moderate
up to 30% oil content but it increased sharply while in
the drying times remained unchanged up to 20% palm
oil content. The commercial medium alkyd resin is
characterized as semidrying [17]. The addition of palm
oil as non-drying oil in the blend with the medium
alkyd contributes significantly to increase the drying
times. Vegetable oils used in coatings have in their
structures significant amount of unsaturated bonds
which accelerate the drying time in the presence of the
drier [18]. Palm oil is relatively saturated and
consequently, the alkyd resin into which it is
incorporated will take longer times to dry. In order to
shorten the drying time, a blend of alkyd resin and
palm oil will require significant quantity of dryer. It is
suggested that in order to reduce the long drying times
of palm oil based alkyd resin; significant unsaturated
bonds must be introduced in the alkyd resin [11].
3000
2000
1000
0
0
Figure 2: dry extract curve of long and medium oil
alkyd resin with quantity of oil
20
40
long alkyd resin
As shown in Figure 3, the viscosity of the blend starts
to decrease at about 10% palm oil. At this percentage,
these are no change in the viscosity of the long oil
alkyd compared with the viscosity without the oil. This
observation must be confirmed by another analysis
because the viscometer used could not read value more
than 5000 cp using spindle n°6. As the value of the
viscosity of virgin commercial resin given by the
manufacturer is between 4500 and 7000cp, we can
suggest that the measured viscosity might be more
than 5000 cp. By adding the palm oil, the decrease of
viscosity is more rapid m*with medium alkyd than with
long oil alkyd resin. Although the trend of the two
blends decrease with increase in palm oil content, long
oil alkyd and palm oil blend showed a corresponding
higher viscosity than medium oil alkyd and palm oil
blend.
As palm oil appears to be a good additive for adjusting
the viscosity [15], it can be used for better control of
viscosity with long oil alkyd than with medium alkyd.
30
25
20
15
10
Figure 4 shows the change of drying time (set-to-touch
time) with the increase in content of palm oil in the
5
0
0
10
20
30
40
50
60
Oil ( % )
medium alkyd resin
long alkyd resin
Figure 4: Drying time curve of long and medium oil
alkyd resin with quantity of oil
3. 5
3.4
Effect of palm oil on drying time of alkyd
blends
medium alkyd resin
Figure 3: Viscosity curve of long and medium oil alkyd
resin with quantity of oil
Drying time ( h )
3.3
Effect of palm oil on viscosity of alkyd resin
blends
60
Oil ( % )
Acid and peroxide value
Peroxide and acid values were measured and the
results obtained are shown in Table 2. The values show
that the inclusion of palm oil in the blend increases the
acid values of both long and medium alkyd resin
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Itoua, B. V. et al. Malaysian Polymer Journal, Vol. 9, No. 2, p 62-66, 2014
blends. Generally, the resin alkyds used in paint
industry have acid values lower than 10 and resin
blends containing palm oil will require the addition of
ingredients that will lower their acidity [15]. In paint
industry, higher acid is to be avoided because of the
risk of corrosion effects. That is why the resin alkyds
used in paint industry have acid value lower than 10.
The acid values obtained for the two resins are moré
than what is required by the industry. Consequently in
such paint systems, it is necessary to use the additive
to reduce the higher acidity.
TABLE 2: Acid, and peroxide values of palm oil and
blends
Parameters
Samples
Palm oil (50%) and
medium
alkyd
resin
(50%)
Palm oil (50%) and long
alkyd resin (50%)
Palm oil
Long alkyd resin
Medium alkyd resin
4.
Acid value
mg (KOH)
Peroxide
value
Mg eq O2 Kg
25,2
0,25
29,92
0,32
51,42
3
2,5
0,56
0,96
1,1
[3]
Patton, T. C., Alkyd Resin Technology.
Interscience, New York and London (1962).
[4]
Trivedi M. K. and Mann A.S., Studies on blends of
alkyd resin and petroleum resin , Paintindia, 2,
57-62 (1991).
[5]
Deligny, P., Tuck, N., Oldring, P.K.T., Resins for
Surface Coatings, John Wiley and Sons,
Chichester, (2000).
[6]
Ikhuoria, E.U., Okieimen, F.E. Obazee, E.O.,
Synthesis and characterizati on of styrenated
rubber seed oil alkyd, Afr. J. Biotech., 10 (10),
1913-1918 (2011).
[7]
Umeobika U.C., Onuegbu T.U Iloamaeke M.I.,
Ekwueme I.J, Synthesis and evaluation of
performance characteristics of rubber seed oilmodified short and medium alkyd resins, Int J.
Sci. Inno. Dis., 3(1), 86-92 (2013).
[8]
O’ Donoghue, M. Garrett, R.,. Datta, V.J.. EIS
investigations of alkyd and epoxy coatings as
they are chemically stripped from steel panels,
Corrosion 2003. San Diego Ca, March, (2003).
[9]
Saravari, O., Phapant, P., Pimpan, V.J.,J. Synthesis
of water-reducible acrylic-alkyd resins based on
modified palm oil , J. Appl. Polym. Sci., 96, 11701175 (2005).
[10]
Issam, A. M., NurulKhizrien A. K., Mazlan, I.,
Physical and Mechanical Properties of Different
Ratios of Palm Oil-Based Alkyd/Epoxy Resins,
Polymer. Plas. Technol. Eng., 50 (12), 1256-1261
(2011).
[11]
Desmond, T. C. and Gan, S. N., Development of
palm oil –based alkyds as UV curable coatings ,
Pigm. Resin and film Technol., 40 (5), 302-310
(2012).
[12]
Gan, S. N. and Kim, T. T., Curing and film
properties of palm stearin alkyds Pigm. Resin
Technol., 28 (5), 283-292 (1999).
[13]
Shahla, A., Yahya, R. and Gan, S. N., Fast physical
drying, high water and salt resistant coating
from non-drying vegetable oil, Progr. Org.
Coatings., 72, 703-708 (2011).
[14]
Issam, A. M. and Cheun, C. Y., A study of the
effect of palm oil on the properties of a new
alkyd resin, Malays. Polym. J., 4 (1), 42-49 (2009).
[15]
Itoua, V. B., ogunniyi, D. S. and Ongoka, P. R.,
Physico-chemical properties of alkyd resins and
palm oil blends , Malays. Polym. J., 7 (2), 4245(2012).
[16]
Adeniyi, S. and Olufunmilayo A., Preparation and
molecular weight determination of soya-beans
and benniseed oil-modified alkyd resins, J. Iran.
Chem. Res., 2, 231-238 (2009).
[17]
Aghaie, H., Ilkhani, A. R. and Sadat, M, Utilization
of Soya bean fatty Acid for Synthesis of Alkyd
resin and Comparison of Properties with Other
Vegetable
Oils.
http://www.iau-
CONCLUSION
Blends of palm oil with long alkyd resin and medium
alkyd resin were prepared and characterized by
studying various physico-chemical properties. The
results show that palm oil contributed to the increase
of drying times of both long and medium alkyd resins.
The viscosity of the blends is lower compared to that
of the pure alkyd. The introduction of palm oil in the
blend may be suitable for paint systems which require
low viscosity. However the increase of drying time of
palm oil blended with long oil alkyd resin is moderate
up to 30% oil content but it increases sharply
thereafter. In the blend of palm oil with medium oil
alkyd, the results show that the drying times remained
practically unchanged up to 20% oil content; with the
increase of palm oil to 30%, the drying times extends to
24h.
The disadvantage of higher acid value can be reduced
by introducing an appropriate additive. Comparatively,
with the other vegetable oils used in paint industry,
palm oil offers some advantages due to its abundance
and low cost.
5.
Alkyd resins, Biores. Technol., 99, 1300-1304
(2008).
AKNOWLODGEMENT
The authors would like to thank the Paint Enterprise
‘’Congolaise de Peinture’’ for technical support.
6.
REFERENCES
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Schwalm, R., UV coatings: Basics, Recent
Developments and New Applications. Elsevier,
Oxford, (2007).
[2]
Ogunniyi, D. S. and Odetoye T. E., Preparation
and Evaluation of Tobacco Seed oil-Modified
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saveh.ac.ir/Files/Journal/201222_06.15.15_7
[18]
04-
Pierre G. and Paul P., Fabrication des resines
alkydes modifies aux huiles : contrôle de la
viscosite in Peinture et Vernis ed. hermann, paris
414-416, (1996).
MPJ 66