STUDY OF THE OPTIMUM CONDITION TOWARDS THE INDUCING PARAFFIN WAX LDPE.
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
9
STUDY OF THE OPTIMUM CONDITION TOWARDS THE INDUCING
PARAFFIN WAX LDPE
Kannan Rassiah(1), Mohd Yuhazri Yaakob(2), Haeryip Sihombing(2), and Puvanasvaran Perumal(2)
(1)
(2)
Department of Mechanical Engineering. Politeknik Merlimau. KB 1031, Pejabat Pos Merlimau-Melaka MALAYSIA
Faculty of Manufacturing Engineering. Universiti Teknikal Malaysia Melaka, Durian Tunggal-Melaka MALAYSIA
Email: kannan@pmm.edu.my
Abstract—Low
Density
Polyethelene
is
a
thermoplastic resin extracted from petroleum based,
whereas the wax is an oily organic component that is
contains of alkanes, ester, polyester, and hydroxyester.
The purpose of this research is to find out the optimum
conditions of the wax produced by inducing LDPE. The
experiment is carried out by mixing the wax and LDPE
into four new polymer compositions, in which the higher
value of the tensile strength, Young’s modulus, and
hardness are obtained by mixing between 90 wt. % LDPE
with 10 wt. % wax, rather than compared to pure LDPE.
The results are 8.896 MPa, 247.602 MPa and 50.9
respectively. However, only the strength impact that has a
lower value as much as 31.38 %. By SEM analysis, the
improvement of mechanical properties value examined in
which the most suitable of optimal composition is 90 wt.
% LDPE with 10 wt. % wax. The LDPE/wax mixture
produces a new polymer and alters the properties of pure
LDPE.
Keywords: low density polyethylene, paraffin wax, new
polymer.
I. INTRODUCTION
P
olymer is a long chain of repeated atoms and
produced by joining the molecules which are known
as monomers. The Low Density Polyethelene (LDPE) is a
first grade of the Polyethylene group which was
produced in 1933 by Imperial Chemical Industries by
using high pressure and ‘free radical polymerisation’
techniques [3], while the wax is an organic compound
which is categorized into two types, that is natural wax
and modified wax. Both types of wax create higher
potential as the reinforcement agent in polymers. The
reason to choose the natural wax in this research due to
the cost of manufacturing as well as it widely used for
consumer products.
II. MATERIAL AND METHODS
This research use low-density polyethylene as the
matrix material in the form of pallet and the wax as
reinforcement material. The wax material was obtained
from the candle sticks that have been processed by the
manufacturers. Most of the candles are made of parafin,
but it can also made from bees wax, soya, plants as well
as cow’s fat (a side product of the beef fat), wheras the
gel wax is made from paraffin and plastic.
Chemically, a candle contains of various compounds
such as alkanes, esters (contains acid and alcohol),
polyesters, low hydroxyester alcohol, and fatty acids. The
wax differs from fat because it lacks triglyceride ester
glycerine propan 1,2,3 triol and three fatty acids. High
melting point and hardness of karnauba candle occurs
when ester is added [1].
The formulation for LDPE and wax is divided into
five main compositions ratio as shown in Table 1. Every
material is mixing into a beaker placed on the top of hot
plate magnetic stirrer. The set up parameter for the
surrounding temperature is fixed with range 95 ºC to 125
ºC with fixed rotator is 600 rpm. The blending takes
about 45 minutes to produce uniform mixture.
Table 1: Compositions ratio of LDPE/wax
Compositions
wt. % LDPE
wt. % Wax
A
B
C
D
E
100
90
80
70
60
0
10
20
30
40
By using crusher machine, the compounds are
processed into smaller sizes. This process is to ensure that
both of the materials are uniformly mix and no lumps
presence due to the smaller lumps are able to influence
the accuration of data analysis. The LDPE/wax
compound was compressed for 15 minutes under 20
tonnes at temperature of 175 ºC followed by cooling at
room temperature.
Five types of new polymer
composition are cut and tested for tensile, harness, and
charpy characteristics according to ASTM D-638 08,
ASTM D-785 08 and ASTM D-6110 08 respectively.
The microscopic observation is carried out to observe the
cracked surface after all of the LDPE/wax polymer
subjected into three mechanical testing. Here, the
morphology of the cracked surface is observed by using
scanning electron microscopy (SEM) at three types of
magnifications that are 250X, 500X and 1000X, which
consists of topographical, morphological and composition
pictures.
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
Tensile test
The test for tensile strength test is being done against
the four major compositions of the mixture with the
percentage of LDPE and wax in between 90 % to 40 %.
This refers to the objective priority of the research that is
to find the higher value of tensile strength for the
LDPE/wax composition of the manufacturing process.
The LDPE 90 wt. % and wax 10 wt. % mixture was
observed and the tensile strength is higher compared to
the other wt. % compositions. The addition of wax shows
a pattern of decrease in its tensile strength and modulus
tensile compared to pure LDPE. At an earlier stage, the
addition of 40 wt. % wax caused a decreasing pattern of
the tensile strength data, compared to pure LDPE.
However, while the wax is further decreased from 40 wt.
% to 10 wt. %, then the tensile strength will increase [5] –
[8]. The result is as shown in Figure 1 and Figure 2.
Stress (MPa)
10
Chart of tensile strength against percentage
composition of LDPE
8.896
8.3
7.222
8
6
46.44. The ductile property of pure LDPE is unable to
withstand hardness. The hardness value of pure LDPE
and LDPE/wax is calculated and shown clearly in Figure
3.
Graph of Durometer strength reading against percentage of
composition of LDPE
Streangth Reading (shore)
III. RESULTS AND DISCUSSION
10
60
50
46.44
50.9
47.8
45.06
40
37.64
30
20
10
0
60
70
80
90
100
LDPEwt%
Figure 3: Graph of Durometer strength reading against
percentage of composition of LDPE
Charpy impact test
Figure 4 proven that the LDPE/wax is lower than pure
LDPE. Theoretically, pure LDPE has high ductile
strength and elasticity. From 90 wt. % LDPE mixture, the
value of energy absorbed is close to pure LDPE, but for
60 wt. % LDPE mixtures, the value has decreased, while
in 80 wt. % LDPE mixture, the value increases but it is
lower compared to pure LDPE [2].
4.166
4
2.518
Graph of impact strength against LDPE percentage of
composition
2
0
80
90
100
LDPE wt%
Figure 1: Chart of tensile strength against percentage
composition of LDPE
0.0274
2
70
impact strength(J/mm )
0.03
60
0.025
0.02
0.0188
0.015
0.0144
0.01
0.00922
0.005
0.00412
0
60
Chart of tension modulus against percentage
composition of LDPE
Modulus of elasticity (MPa)
300
70
80
90
100
LDPE wt%
Figure 4: Graph of impact strength against LDPE
percentage of composition
247.602
250
205.672
200
222.5
170.028
170
150
100
50
0
60
70
80
90
100
LDPE wt%
Surface morphology of cracked specimens
The analyses towards surface morphology of the
broken specimens carried out by using scanning electron
microscope after the impact testing. The morphology is
used to identify the bonds between the LDPE and wax
structures. It is also used to find the changes on the
material after being tested with a strong impact.
Figure 2: Chart of tension modulus against percentage
composition of LDPE
wax
Hardness test
The high hardness value of the mixture shows the
property of the material, which has high hardness level.
The hardness value of 60 wt. % LDPE is 37.64
meanwhile the value for 90 wt. % LDPE is 50.9. The
significant differences in the value shows that the high
percentage of wax will decrease the hardness of the
material as the bonding between the molecules become
irregular. Comparison is also done between pure LDPE
and 90 wt. % LDPE and it shows that the hardness value
of pure LDPE is lower than 90 wt. % LDPE, that is,
LDPE
Figure 5: Mixture of 60 wt. % LDPE (1000X)
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
The X- ray test is also done to identify the contents of
the mixture. The energy traces represents the overall
energy of the impact on the specimen whereas the
strength of the impact represents the overall energy that
has been absorbed by the specimen when weight is
applied.
Figure 5 shows the wax 40 wt. % has covered the
borders and most of the area. This caused the bonds
between LDPE to be broken and changed the mechanical
properties. It also decreased the tensile strength [4], [6],
[8]. From the result also shows the percentage of carbon
is 67.06 wt. %. This proves the presence of carbon in the
mixture because LDPE and wax contains high percentage
of carbon.
11
have started to bind the LDPE molecules, indirectly
modifying the mechanical characteristics of the LDPE
[4], [6], [8]. The high percentage of LDPE has increased
the carbon wt. % in the mixture up to 77.16 wt. % and the
morphological picturisation shows that the LDPE
molecule has started to bind with the wax molecules,
consequently adding the carbon wt%.
wax
LDPE
Figure 8: Mixture of 90 wt. % LDPE (1000X)
wax
LDPE
Figure 6: Mixture of 70 wt. % LDPE (1000X)
Figure 6 shows 70 wt. % LDPE that is very different of
60 wt. %, because the LDPE structure can be seen. Even
though the certain areas of the molecule are covered with
wax. The tensile strength also decreased, but it remains
higher than 60 wt. % LDPE [4], [7], [8]. The percentage
of carbon in this mixture increases up to 69.82 wt. %. The
increase of LDPE influences the percentage of carbon.
LDPE
wax
Figure 7: Mixture of 80 wt. % LDPE (1000X)
In this mixture as shown in Figure 7, the changes can
be seen in the properties. The wax is the binder for
LDPE. The wax molecules have covered the borders and
In Figure 8, it can be seen that the mixing ratio has
started to properly occur and produce a new LDPE/wax
properties where the polymer has combined regularly.
The wax is found in all the borders and tied the molecules
of the polymer. The tensile strength increases, although
the pure LDPE properties is still maintain [4], [6], [8]. By
increasing of the carbon’s percentage up to 81.80 wt. %
in this composition, it’s proves that the addition of LPDE
in this mixture will strengthen the percentage of carbon in
this molecule and the wax will act as the binder for this
molecule.
IV. CONCLUSIONS
Based on the mechanical properties results (which is
obtained from the tensile strength test and hardness test),
it is known that the mechanical characteristics of LDPE
increases. However, its decreases when the impact test is
done. This shows that the mixture is hard, but it is more
ductile compared to pure LDPE.
Based on the observation, the best wt. % mixture for
these two materials is 90 wt. % LDPE and 10 wt. % wax.
This wt. % has increased the mechanical characteristics
of the pure LDPE. The morphology test on the broken
surface shows that the adhesion between wax and LDPE
is a strong bond. But if the mixture is unproportional,
then the LDPE characteristics will decrease.
The research also shows that is apart of increasing the
strength against an object, LDPE also able to increase the
income due to wax is less expensive and readily
available. The usage of injection moulding process will
also improve because the wax acts as a conductor during
this process.
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
ACKNOWLEDGMENT
The authors would like to thanks Director of
Polytechnic Merlimau Melaka, Head of Mechanical
Engineering Department, as well as The Unit of
Research, Innovation & Entrepreneurship of Politeknik
Merlimau whose supports the project.
REFERENCES
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
Baker, W., Scott, C., and G.H. Hu (2001). ”Reactive Polymer
Blending.” 1st. ed. Munich: Hanser Publishers, p 24-30.
Doan, T.T.L., Gao, S.L., and E. Mader (2006). Jute/Polypropylene
Composite I. Effect of Matrix Modification. Composites Science
and Technology. Vol. 66, p. 952-963.
Kalpakjian, S., and Schmid, S.R. (2000). ”Manufacturing
Engineering And Technology”. 4th.Ed. New Jersey: Prentice
Hall,Inc. p.177-193.
Chuayjuljit, S., Hosililak, S., and A. Athisart (2009).
Thermoplastic
Cassava
Starch/
SorbitalModified
Montmorillonite Nanocomposites Blended with Low Density
Polyethylene: Properties and Biodegradability study. Journal of
Metals, Materials and Minerals, Vol.19 No.1, p.59-65.
Young, C.N., Jeong, K., and H.K. Phil. (2006) “Mechanical
Properties of LDPE/Ethylene-1-butene Copolymer Films
Crosslinked by Radiation” J. Ind. Eng. Chem., Vol. 12, No. 6,
p.888-892
Shuhadah, S. and Supri, A.G. (2009) “LDPE-Isophthalic AcidModified Egg Shell Powder Composites (LDPE/ESPI)” Journal of
Physical Science, Vol. 20 No. 1, p.87–98.
Supri, A.G, Salmah, H., and K. Hazwan (2008) ”Low Density
Polyethylene-Nanoclay Composites: The Effect of Poly(acrylic
acid) on Mechanical Properties, XRD, Morphology Properties and
Water Absorption” Malaysian Polymer Journal (MPJ), Vol 3 No.
2, p 39 -53.
Wan Aizan, W.A.R., Roshafima, R.A., and Z. Naterah. (2006)
“Studies on Biodegradability, Morphology and Mechanical
Properties of Low Density Polyehtylene/Sago Based Blends”
Proceedings of the 1st International Conference on Natural
Resources Engineering & Technology 24-25th July 2006;
Putrajaya, Malaysia, p. 434-444
12
9
STUDY OF THE OPTIMUM CONDITION TOWARDS THE INDUCING
PARAFFIN WAX LDPE
Kannan Rassiah(1), Mohd Yuhazri Yaakob(2), Haeryip Sihombing(2), and Puvanasvaran Perumal(2)
(1)
(2)
Department of Mechanical Engineering. Politeknik Merlimau. KB 1031, Pejabat Pos Merlimau-Melaka MALAYSIA
Faculty of Manufacturing Engineering. Universiti Teknikal Malaysia Melaka, Durian Tunggal-Melaka MALAYSIA
Email: kannan@pmm.edu.my
Abstract—Low
Density
Polyethelene
is
a
thermoplastic resin extracted from petroleum based,
whereas the wax is an oily organic component that is
contains of alkanes, ester, polyester, and hydroxyester.
The purpose of this research is to find out the optimum
conditions of the wax produced by inducing LDPE. The
experiment is carried out by mixing the wax and LDPE
into four new polymer compositions, in which the higher
value of the tensile strength, Young’s modulus, and
hardness are obtained by mixing between 90 wt. % LDPE
with 10 wt. % wax, rather than compared to pure LDPE.
The results are 8.896 MPa, 247.602 MPa and 50.9
respectively. However, only the strength impact that has a
lower value as much as 31.38 %. By SEM analysis, the
improvement of mechanical properties value examined in
which the most suitable of optimal composition is 90 wt.
% LDPE with 10 wt. % wax. The LDPE/wax mixture
produces a new polymer and alters the properties of pure
LDPE.
Keywords: low density polyethylene, paraffin wax, new
polymer.
I. INTRODUCTION
P
olymer is a long chain of repeated atoms and
produced by joining the molecules which are known
as monomers. The Low Density Polyethelene (LDPE) is a
first grade of the Polyethylene group which was
produced in 1933 by Imperial Chemical Industries by
using high pressure and ‘free radical polymerisation’
techniques [3], while the wax is an organic compound
which is categorized into two types, that is natural wax
and modified wax. Both types of wax create higher
potential as the reinforcement agent in polymers. The
reason to choose the natural wax in this research due to
the cost of manufacturing as well as it widely used for
consumer products.
II. MATERIAL AND METHODS
This research use low-density polyethylene as the
matrix material in the form of pallet and the wax as
reinforcement material. The wax material was obtained
from the candle sticks that have been processed by the
manufacturers. Most of the candles are made of parafin,
but it can also made from bees wax, soya, plants as well
as cow’s fat (a side product of the beef fat), wheras the
gel wax is made from paraffin and plastic.
Chemically, a candle contains of various compounds
such as alkanes, esters (contains acid and alcohol),
polyesters, low hydroxyester alcohol, and fatty acids. The
wax differs from fat because it lacks triglyceride ester
glycerine propan 1,2,3 triol and three fatty acids. High
melting point and hardness of karnauba candle occurs
when ester is added [1].
The formulation for LDPE and wax is divided into
five main compositions ratio as shown in Table 1. Every
material is mixing into a beaker placed on the top of hot
plate magnetic stirrer. The set up parameter for the
surrounding temperature is fixed with range 95 ºC to 125
ºC with fixed rotator is 600 rpm. The blending takes
about 45 minutes to produce uniform mixture.
Table 1: Compositions ratio of LDPE/wax
Compositions
wt. % LDPE
wt. % Wax
A
B
C
D
E
100
90
80
70
60
0
10
20
30
40
By using crusher machine, the compounds are
processed into smaller sizes. This process is to ensure that
both of the materials are uniformly mix and no lumps
presence due to the smaller lumps are able to influence
the accuration of data analysis. The LDPE/wax
compound was compressed for 15 minutes under 20
tonnes at temperature of 175 ºC followed by cooling at
room temperature.
Five types of new polymer
composition are cut and tested for tensile, harness, and
charpy characteristics according to ASTM D-638 08,
ASTM D-785 08 and ASTM D-6110 08 respectively.
The microscopic observation is carried out to observe the
cracked surface after all of the LDPE/wax polymer
subjected into three mechanical testing. Here, the
morphology of the cracked surface is observed by using
scanning electron microscopy (SEM) at three types of
magnifications that are 250X, 500X and 1000X, which
consists of topographical, morphological and composition
pictures.
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
Tensile test
The test for tensile strength test is being done against
the four major compositions of the mixture with the
percentage of LDPE and wax in between 90 % to 40 %.
This refers to the objective priority of the research that is
to find the higher value of tensile strength for the
LDPE/wax composition of the manufacturing process.
The LDPE 90 wt. % and wax 10 wt. % mixture was
observed and the tensile strength is higher compared to
the other wt. % compositions. The addition of wax shows
a pattern of decrease in its tensile strength and modulus
tensile compared to pure LDPE. At an earlier stage, the
addition of 40 wt. % wax caused a decreasing pattern of
the tensile strength data, compared to pure LDPE.
However, while the wax is further decreased from 40 wt.
% to 10 wt. %, then the tensile strength will increase [5] –
[8]. The result is as shown in Figure 1 and Figure 2.
Stress (MPa)
10
Chart of tensile strength against percentage
composition of LDPE
8.896
8.3
7.222
8
6
46.44. The ductile property of pure LDPE is unable to
withstand hardness. The hardness value of pure LDPE
and LDPE/wax is calculated and shown clearly in Figure
3.
Graph of Durometer strength reading against percentage of
composition of LDPE
Streangth Reading (shore)
III. RESULTS AND DISCUSSION
10
60
50
46.44
50.9
47.8
45.06
40
37.64
30
20
10
0
60
70
80
90
100
LDPEwt%
Figure 3: Graph of Durometer strength reading against
percentage of composition of LDPE
Charpy impact test
Figure 4 proven that the LDPE/wax is lower than pure
LDPE. Theoretically, pure LDPE has high ductile
strength and elasticity. From 90 wt. % LDPE mixture, the
value of energy absorbed is close to pure LDPE, but for
60 wt. % LDPE mixtures, the value has decreased, while
in 80 wt. % LDPE mixture, the value increases but it is
lower compared to pure LDPE [2].
4.166
4
2.518
Graph of impact strength against LDPE percentage of
composition
2
0
80
90
100
LDPE wt%
Figure 1: Chart of tensile strength against percentage
composition of LDPE
0.0274
2
70
impact strength(J/mm )
0.03
60
0.025
0.02
0.0188
0.015
0.0144
0.01
0.00922
0.005
0.00412
0
60
Chart of tension modulus against percentage
composition of LDPE
Modulus of elasticity (MPa)
300
70
80
90
100
LDPE wt%
Figure 4: Graph of impact strength against LDPE
percentage of composition
247.602
250
205.672
200
222.5
170.028
170
150
100
50
0
60
70
80
90
100
LDPE wt%
Surface morphology of cracked specimens
The analyses towards surface morphology of the
broken specimens carried out by using scanning electron
microscope after the impact testing. The morphology is
used to identify the bonds between the LDPE and wax
structures. It is also used to find the changes on the
material after being tested with a strong impact.
Figure 2: Chart of tension modulus against percentage
composition of LDPE
wax
Hardness test
The high hardness value of the mixture shows the
property of the material, which has high hardness level.
The hardness value of 60 wt. % LDPE is 37.64
meanwhile the value for 90 wt. % LDPE is 50.9. The
significant differences in the value shows that the high
percentage of wax will decrease the hardness of the
material as the bonding between the molecules become
irregular. Comparison is also done between pure LDPE
and 90 wt. % LDPE and it shows that the hardness value
of pure LDPE is lower than 90 wt. % LDPE, that is,
LDPE
Figure 5: Mixture of 60 wt. % LDPE (1000X)
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
The X- ray test is also done to identify the contents of
the mixture. The energy traces represents the overall
energy of the impact on the specimen whereas the
strength of the impact represents the overall energy that
has been absorbed by the specimen when weight is
applied.
Figure 5 shows the wax 40 wt. % has covered the
borders and most of the area. This caused the bonds
between LDPE to be broken and changed the mechanical
properties. It also decreased the tensile strength [4], [6],
[8]. From the result also shows the percentage of carbon
is 67.06 wt. %. This proves the presence of carbon in the
mixture because LDPE and wax contains high percentage
of carbon.
11
have started to bind the LDPE molecules, indirectly
modifying the mechanical characteristics of the LDPE
[4], [6], [8]. The high percentage of LDPE has increased
the carbon wt. % in the mixture up to 77.16 wt. % and the
morphological picturisation shows that the LDPE
molecule has started to bind with the wax molecules,
consequently adding the carbon wt%.
wax
LDPE
Figure 8: Mixture of 90 wt. % LDPE (1000X)
wax
LDPE
Figure 6: Mixture of 70 wt. % LDPE (1000X)
Figure 6 shows 70 wt. % LDPE that is very different of
60 wt. %, because the LDPE structure can be seen. Even
though the certain areas of the molecule are covered with
wax. The tensile strength also decreased, but it remains
higher than 60 wt. % LDPE [4], [7], [8]. The percentage
of carbon in this mixture increases up to 69.82 wt. %. The
increase of LDPE influences the percentage of carbon.
LDPE
wax
Figure 7: Mixture of 80 wt. % LDPE (1000X)
In this mixture as shown in Figure 7, the changes can
be seen in the properties. The wax is the binder for
LDPE. The wax molecules have covered the borders and
In Figure 8, it can be seen that the mixing ratio has
started to properly occur and produce a new LDPE/wax
properties where the polymer has combined regularly.
The wax is found in all the borders and tied the molecules
of the polymer. The tensile strength increases, although
the pure LDPE properties is still maintain [4], [6], [8]. By
increasing of the carbon’s percentage up to 81.80 wt. %
in this composition, it’s proves that the addition of LPDE
in this mixture will strengthen the percentage of carbon in
this molecule and the wax will act as the binder for this
molecule.
IV. CONCLUSIONS
Based on the mechanical properties results (which is
obtained from the tensile strength test and hardness test),
it is known that the mechanical characteristics of LDPE
increases. However, its decreases when the impact test is
done. This shows that the mixture is hard, but it is more
ductile compared to pure LDPE.
Based on the observation, the best wt. % mixture for
these two materials is 90 wt. % LDPE and 10 wt. % wax.
This wt. % has increased the mechanical characteristics
of the pure LDPE. The morphology test on the broken
surface shows that the adhesion between wax and LDPE
is a strong bond. But if the mixture is unproportional,
then the LDPE characteristics will decrease.
The research also shows that is apart of increasing the
strength against an object, LDPE also able to increase the
income due to wax is less expensive and readily
available. The usage of injection moulding process will
also improve because the wax acts as a conductor during
this process.
International Journal of Engineering & Technology IJET-IJENS Vol: 10 No: 04
ACKNOWLEDGMENT
The authors would like to thanks Director of
Polytechnic Merlimau Melaka, Head of Mechanical
Engineering Department, as well as The Unit of
Research, Innovation & Entrepreneurship of Politeknik
Merlimau whose supports the project.
REFERENCES
[1]
[2]
[3]
[4]
[5]
[6]
[7]
[8]
Baker, W., Scott, C., and G.H. Hu (2001). ”Reactive Polymer
Blending.” 1st. ed. Munich: Hanser Publishers, p 24-30.
Doan, T.T.L., Gao, S.L., and E. Mader (2006). Jute/Polypropylene
Composite I. Effect of Matrix Modification. Composites Science
and Technology. Vol. 66, p. 952-963.
Kalpakjian, S., and Schmid, S.R. (2000). ”Manufacturing
Engineering And Technology”. 4th.Ed. New Jersey: Prentice
Hall,Inc. p.177-193.
Chuayjuljit, S., Hosililak, S., and A. Athisart (2009).
Thermoplastic
Cassava
Starch/
SorbitalModified
Montmorillonite Nanocomposites Blended with Low Density
Polyethylene: Properties and Biodegradability study. Journal of
Metals, Materials and Minerals, Vol.19 No.1, p.59-65.
Young, C.N., Jeong, K., and H.K. Phil. (2006) “Mechanical
Properties of LDPE/Ethylene-1-butene Copolymer Films
Crosslinked by Radiation” J. Ind. Eng. Chem., Vol. 12, No. 6,
p.888-892
Shuhadah, S. and Supri, A.G. (2009) “LDPE-Isophthalic AcidModified Egg Shell Powder Composites (LDPE/ESPI)” Journal of
Physical Science, Vol. 20 No. 1, p.87–98.
Supri, A.G, Salmah, H., and K. Hazwan (2008) ”Low Density
Polyethylene-Nanoclay Composites: The Effect of Poly(acrylic
acid) on Mechanical Properties, XRD, Morphology Properties and
Water Absorption” Malaysian Polymer Journal (MPJ), Vol 3 No.
2, p 39 -53.
Wan Aizan, W.A.R., Roshafima, R.A., and Z. Naterah. (2006)
“Studies on Biodegradability, Morphology and Mechanical
Properties of Low Density Polyehtylene/Sago Based Blends”
Proceedings of the 1st International Conference on Natural
Resources Engineering & Technology 24-25th July 2006;
Putrajaya, Malaysia, p. 434-444
12