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Al-Qadisiyah Journal For Engineering Sciences,         Vol. 10……No. 1….2017 

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THE INFLUENCE OF LOW COST FILLER ON SOME 

MECHANICAL AND PHYSICAL PROPERTIES OF A POLYMER 

MATRIX COMPOSITE  
 

Orhan Sabah Abdullah 

Assistant Lecturer 

U.O.Technology - Mechanical Eng. Dep. 

orhan_sabah@yahoo.com 

Received on 15 June 2016        Accepted on 30 November 2016 

 
Abstract 

Experimental study has been done in this research to explain the influence of low cost fillers 

contents on the mechanical and physical properties of unsaturated polyester resin composite with 

different weight fraction. The effect of three particles; Baby powder particles including MgO, Fire 

extinguisher particles including CaCO3 and chalk particles including SiO2 with weight fraction of 

(5%, 10%, 15%)Wf% added to polyester matrix on the wear rate under dry sliding conditions, 

hardness, thermal conductivity, and water absorption has been investigated. The wear rate was 

measured according to ASTM G99-05 standard with pin on disc machine, hardness measured 

according to ASTM D-2240 Shore D hardness test, Lee's disc technique used to measure thermal 

conductivity, while water absorption measured according to ASTM D 570 standard. The results 

shows that the addition of fillers leads to increasing the wear resistance, hardness and water 

absorption and decrease the thermal conductivity with the increasing in reinforcement material 

weight fraction. while, the wear resistance decreasing with increase in applied load. The results 

appeared that the addition of particles to polyester resin leads to increase in all the mechanical and 

physical properties tested in this research better than polyester specimen only and MgO-polyester 

composite given the best wear resistance. 

Keywords: polyester composite; MgO, SiO2, CaCO3; wear behavior, hardness…etc. 

 
 بولیمریة متراكبة لمادة بعض الخواص المیكانیكیة والفیزیائیة على الكلفة منخفضة االضافات تاثیر دراسة

 
 عبدهللا صباح أورھان
 مساعد مدرس

 الخالصة 

لراتنج البولیستیر الغیر مشبع  على الخواص المیكانیكیة والفیزیائیة  تأثیر الحشوات منخفضة الكلفة دراسة تمت البحث ھذا في
أن مواد التدعیم المستخدمة في ھذا البحث كانت ھي عبارة عن دقائق وزنیة مختلفة.  كسور عند عملیا بالدقائق  المقواة 

، دقائق مطفاءة  MgOمحضرة من مواد بسیطة منخفضة الكلفة وھي: دقائق بودرة االطفال الحاویة على اوكسید المغنسیوم 
وبحجم حبیبي  SiO2ق مادة الطباشیر الحاویة على اوكسید السیلیكون ، ودقائ CaCO3الحریق الحاویة كاربونات الكالسیوم 

10μm )  لدراسة سلوك البلیان والصالدة والموصلیة الحراریة وامتصاصیة الماء عند ١٥، ١٠%، ٥وبكسور وزنیة (%
باستعمال جھاز   ASTM G99-05حیث تم دراسة مقاومة البلیان وفقا للمواصفة اضافتھا الى مادة البولیستر الغیر مشبع.

تم قیاس الموصلیة الحراریة بأستخدام قرص .  ASTM D-2240وقیاس الصالدة وفقا للمواصفة  المسمار مع القرص الدوار
.وقد اظھرت النتائج ان اضافة مواد التدعیم ادت الى زیادة  ASTM D 570لي بینما تم قیاس امتصاصیة الماء وفقا للمواصفة

متصاصیة الماء وخفض الموصلیة الحراریة مع زیادة الكسر الوزني لمواد التدعیم وان زیادة الحمل مقاومة البلیان والصالدة وا
المسلط خالل اختبار البلیان اى الى زیادة معدل البلى المقاس. واضھرت النتائج ایضاً ان جمیع مواد التدعیم المضافة للبولیستر 


Al-Qadisiyah Journal For Engineering Sciences,         Vol. 10……No. 1….2017 

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% من دقائق اوكسید المغنسیوم عن ١٥ن افضل نسبة تدعیم كانت ھي اعطت نتائج افضل من عینات البولیستر الغیر مدعم وا
 اضافتة الى راتنج االبولیستر.

1. Introduction  

Polymeric composites have become main part of manufacturing application due to their 

unique thermal and mechanical properties apart from their easy process ability and low cost. Such 

materials are good candidates to form a special class of engineering tribo- materials due to their 

unique properties such as wear resistance, impact resistance, corrosion resistance and ease of 

fabrication. They are utilized in numerous applications including seals, cutting tools, bearings and 

artificial prosthetic joints. For such applications and others, polymer matrix must with stand high 

mechanical and tribological loads, so fillers, fibers or particles and added to enhance its properties 

[1].  

Polymer composite has been widely used to substitute the conventional metals and ceramics in 

microelectronic bundling, coating, aerospace, automotive and biomedical applications. This is 

fundamentally because of their unique strength, lightness, versatility, ease of treatment and low 

cost. By adding of reinforcement particles, the tribological properties of polymers are in general 

enhancement [2]. 

The using of micro particles as a reinforcement material in polymers composite has attracted extra 

attentions. The very high specific surface area eases creating a mighty amount of interphase in 

composite and a strong interaction between the particles and the matrix. Particles can enhancement 

the mechanical and physical properties of polymers. Some of these particles it will used to reinforce 

polymers are (SiO2, MgO and SiC) due to its rigidity and high stability [3]. 

Wear is defining as harm in a solid surface, generally including gradual loss of materials, caused by 

relative motion between two surfaces. The general kinds of wear are abrasive, fretting, erosion, 

adhesive and fatigue wear, which are usually seen in practical cases. The ingrained scarcity of 

polymers could be change successfully by using different special particles [4]. 

In order to obtain the wear resistance, hardness, water absorption and dielectric strength many 

researchers modified polymers using different fillers. Briscoe et al., notified that the wear rate of 

high density polyethylene (HDPE) was decreased with the addition of inorganic particles, like CuO 

and Pb3O4 [5]. Husam .A. Kareem studied the mechanical properties of polyester resin reinforced 

by nickel powder, the results showed improved material toughness, fracture toughness, compression 

strength and wear resistance with the increasing of volume fraction and using of (10μm) particle 

size. The result also showed that the wear rate increase with the increasing of load and temperature 

[6]. Haqi I.Gattea, study the effect of Magnesium oxide (MgO) with (5 μm) particle size with 

different Weight percentages (5%,15%,25%) was added to conbextra epoxy (EP-10) resin and 

measured the changing in thermal insulation to this resin. the results show improved thermal 

insulation of the resin by reduced in thermal conductivity coefficient value after oxide addition , and 

the value of thermal insulation will increased with increasing of additive percentage of magnesium 

oxide [7]. 

Amar .J. Bader et.al, prepared polyester matrix composites reinforced with short glass fiber and 

reinforced with glass fiber and Al2O3 particles with different weight fractions (3, 5, and 7 wt% 

Al2O3) and study some of mechanical properties to the prepared composites. The results shows the 

mechanical properties improve with increasing weight fraction [8].  

Ali Al-Mosawi, study the mechanical and thermal properties of epoxy (EP-10) resin reinforced by 

Magnesium oxide (MgO) with (5 μm) particle size with different Weight percentages 

(10%,20%,30%) the results show improved thermal insulation of the resin by reduced in thermal 

conductivity coefficient value and improvement in impact strength, tensile strength, and 

compression strength after oxide addition [9]. 

Ibtihal et al., studying the effect of 10μm (granite, perlite and CaCO3) particles used as a 

reinforcement material for carbon fiber-epoxy composite on wear behavior, and they observed that 

the adding of particles leads to increase the wear resistance [10].    


Al-Qadisiyah Journal For Engineering Sciences,         Vol. 10……No. 1….2017 

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In this work a new polymer composite are prepared to investigate the wear properties, hardness, 

water absorption and thermal conductivity of polyester composite reinforced with low cost 

materials; Baby powder particles including MgO, Fire extinguisher particles including CaCO3 and 

chalk particles including SiO2 with weight fraction of (5%, 10%, 15%)Wf%. 

 
2. Experimental details 

2.1 Materials 

Baby powder particles including MgO, Fire extinguisher particles including CaCO3 and chalk 

particles including SiO2 with grain size (10 μm) and weight fraction (5%,10%, and 15%) used as a 

reinforcement material for polyester resin. Unsaturated polyester used as a matrix material produced 

by (SIR). It is in liquid state at room temperature but after adding the hardener will change to solid 

state. The hardener used to this purpose Methyl Ethyl Keton Peroxide with mixing ratio 1:50 

hardener to polyester resin at room temperature. The properties of the matrix material shown in 

Table.1. 

2.2 Specimens Preparation 

Hand layup technique was used in this research to prepare the specimens. Glass mould used to 

casting the composite material specimens with dimension of (200, 150, and 10) mm as shown in 

Fig.1. The inner face of the mould was covered with a layer of Vaseline to ensure no-adhesion 

between the polymeric material and the mould. The composite material is prepared by mixing the 

polyester resin with the hardener in (3:1) ratio at room temperature with a very slow mixing by 

using glass rod for (15min) until the polymer material will be homogenous, 10μm particulate fillers 

with 5, 10, and 15 wf% of MgO, SiO2 and CaCO3 added to polyester resin respectively and the 

mixing continuous until it becomes homogenous, After (2min) the mixing was completed, To 

prevent air from including inside the specimens we should poured the mixing from one side of the 

mould and slowly, After 24 hours the solidification process is completed for all moulds and we can 

released the casts from the moulds.  

 
3. Mechanical and physical test 

3.1 wear test  
According to ASTM G99-05 wear test standard the casts are cut with dimensions as shown in 

Fig.2.to prepared wear test specimens. Pin-on-Dick test instrument in Applied Science 

Deportment/university of technology shown in the Fig.3 was used to fulfillment the wear test. The 

effect of different weight fraction and loading, on wear rate was studied according to Eq. (1). The 

steel disc have hardness of (385 HV), speed of (200 r.p.m), and rotating radius of (90 mm). Wear 

tests were carried with sliding time about (900s) and loads ranging from (10-30 N). By using 

sensitive balance weight with an accuracy of (10
-4

 g) the initial weight of all the specimens was 

measured. After the test ending all the specimens weighed again to calculate the weight loss due to 

wear. The variance in weight measured before and after tests gives full conception about wear 

behaviour of the composite specimen. To consider the volume wear rate using Eq. (1). 

Wear rate (volume) (cm
3
/m) = 

!"#!$
%&'(   ………………………………………..… (1)  

Where: W1: weight before testing (g), W2: weight after testing (g), ρ: density (g/cm
3
) and S: sliding 

distance (m) calculated form Eq. (2).  

S=2πrnt …………………………………………………………………………. (2) 

n = disc rotational speed, r.p.m, r = the distance from the center of the sample to the center of disc, 

m, t = time of testing, min. 

 
3.2 Hardness test  
This test is performed by using hardness (Shore D) and according to (ASTM D-2240) standard at 

room temperature. Samples have been cut into a disk with (40mm) and a thickness of (5mm) as 


Al-Qadisiyah Journal For Engineering Sciences,         Vol. 10……No. 1….2017 

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shown in Fig.4 while fig.5 shows hardness device used in this research. For each specimen three 

hardness measurements were taken and the average hardness is calculated. 

 
3.3 Thermal conductivity test  

The Lee's disc, manufactured by Griffin and George, Ltd., is used to measure thermal conductivity. 

The apparatus shown in Fig.6 consists of four identical copper discs of (40mm) in diameter and 

(12.25 mm) thickness, one of them includes an electric heater inside denoted by (H). The specimen 

(S) with the (40 mm) in diameter and (5 mm) thickness as shown in Fig.7 is placed between the 

discs (A) and (B), while the heater (H) is sandwiched between (B) and (C) discs. Temperatures of 

(A), (B) and (C) discs are measured by using three thermometers. Thermal conductivity coefficient 

is then calculated according to eq.(3) & (4). The average of three measurements is taken for each 

specimen to minimize the possible errors. 

 
)* = +,$-./0 1 /23 1 4+,-560/0 1
78
$
./0 1 /93 1 69/9 1 62/2: ……………….. (3) 

; 5<>#<?78 : = -@/0 1
$
A 560 1

"
B 6%:/0 1

"
$A 6%/CD …………………………..………. (4) 

 
3.4 Water absorption 

Disc specimens were prepared with diameter of 40 mm and thickness 5mm in order to obtain the 

water absorption of the composite material. The specimens weighted before and after immersion in 

water according to ASTM D 570 standard as shown in Fig.8. The increase in the weight of the 

specimens was calculated by using equation (5):  

 
Water absorption= EFGHI'JKFLMN'#OPFLFGHI'JKFLMNOPFLFGHI'JKFLMN  ………………………………... (5) 
The specimens were immersion for one hundred days in water and it was weighted every ten days. 

 
4. Results and Discussion 

4.1 Wear Test 

Wear tests were carried out for all specimen prepared from polyester resin and polyester with 

different weight fractions of reinforcement particles. Pin on disc wear test carried out for all the 

specimens different diagrams are sketched and presenting in Fig.9 and Fig.10.For different 

percentage of weight fractions under various test conditions.(Weight fraction, and applied Load). 

4.1.1 The effect of weight fraction: 

The samples presented a good wear resistance with the increasing in weight fraction of (MgO, 

CaCO3, and SiO2) particles as shown in Fig.9. When we compered the wear resistance results of 

composite material after adding the reinforced particles with the result of polyester specimen we 

can observed an increasing about (62.5%, 42%, and 36.75%) in wear resistance respectively. 

 
4.1.2 The effect of applied load: 

The effect of various normal applied loads on the wear rate was studied for specimens before and 

after adding the reinforced particles with constant test conditions such as sliding time (900 sec), 

sliding distance (1507.2m) and the rotating disc speed 200 rpm. From the results we can observed 

the all the specimens have a decrease in wear resistance with the increasing in normal applied load. 

This behaviour can be discussed simply when a high load applied to the specimen surface more 

fraction will happened on it and thus leads to increasing wear rate. 

The increase in wear rate of composite materials with 15% (MgO, CaCO3, and SiO2) shown in 

Fig.10. The increase recorded appeared by (34.4%, 47.5%, and 62.6%) respectively in wear rate 


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with load increasing, but when compared with polyester specimen at the same test conditions its 

observed increase in wear resistance recorded by (54.2%, 35,3%, and 22%) respectively. 

 
4.2 Hardness test  
Hardness test type shore (D) has been carried out on polyester before and after adding the 

reinforcement particles and the average of three readings in each case taken to obtain higher 

accuracy results. 

From Fig.11 it can observed that the addition of reinforcement materials leads to increase the 

hardness of the composite material and the specimens reinforced with 15% MgO have higher 

hardness than CaCO3 and SiO2 specimens. A similar behavior seen by Aseel Mahmood et.al when 

used alumina particles as reinforcement material to polyester resin with (20µm) grain size and 8% 

weight fraction [11]. 

 
4.3 Thermal conductivity  
    The thermal conductivity of prepared composites specimens are measured by Lee's disc 

technique and the experimental results are shown in Fig.12 .It can be see that the addition of 

ceramic fillers (MgO, CaCO3, and SiO2) to polyester resin leads to decrease the thermal 

conductivity will be high as there results good agreement with result obtained by [9]. And the use of 

MgO gives the best results as insulation material between the other materials uses in this research. 

 
4.4 Water absorption  
Water absorption behaviors of the composite in water immersion against the time in (days) are 

shown in Fig.13, 14, &15. The addition of (MgO, CaCO3, and SiO2) particles leads to increase the 

water absorption with the increasing in reinforcement material weight fraction%. A similar behavior 

was seen by N. W. A. Razak and A. Kalam
 
with the addition of natural fiber or particles the water 

absorption increase due to the poor interfacial bonding made the composite material may be 

containing voids and porosity [12].  

 
5. CONCLUSIONS 

1- The wear rate for all the prepared specimens was increased with the increasing in applied load. 

2- The addition of reinforced particles leads to increase the wear resistance of composite material 

better than polyester specimen without reinforcement material. 

3- The mixture of 15% MgO with polyester resin has the highest wear resistance, which is 62.5 % 

better than that polyester specimen. 

4- MgO- Polyester composite has the best wear resistance, hardness, thermal in when compared 

with CaCO3-Polyester and SiO2-Polyester composites. 

5- The addition of (MgO, CaCO3, and SiO2) particles to polyester resin leads to increase hardness 

and water absorption with the increasing in reinforcement material weight fraction. 

6- The thermal conductivity decreasing with the increase in reinforcement weight fraction.     

References 

[1] Pedro V., Jorge F., Antonio M. and Rui L., 2006, Tribological behavior of epoxy based 

composites for rapid tooling, Journal of Wear, Vol.260, pp. 30-39. 

[2] Suresha, B. G. Chandramohan, J.N. Prakash, V. Balusamy and K. Sankarayanasamy, 2006, The 

Role of Fillers on Friction and Slide Wear Characteristics in Glass-Epoxy Composite Systems, 

Journal of Minerals and Materials Characterization and Engineering, Vol.5, No.1. 

[3] Suresha, B. G. Chandramohan, J.N. Prakash, V. Balusamy and K. Sankarayanasamy, ”The Role 

of Fillers on Friction and Slide Wear Characteristics in Glass-Epoxy Composite Systems”, Journal 

of Minerals and Materials Characterization and Engineering, Vol.5, No.1, (2006). 


Al-Qadisiyah Journal For Engineering Sciences,         Vol. 10……No. 1….2017 

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[4] Patel R., Kishorekumar B. and Gupta N.,2009, Effect of Filler Materials and Preprocessing 

Techniques on Conduction Processes in Epoxy-based Nanodielectrics, IEEE Electrical Insulation 

Conference, Montreal, QC, Canada. 

[5] - Briscoe, B. J., Pogosion, A. K., and Tabor, D., 1974, The friction and wear of high Density 

polyethylene; the action of lead oxide and copper oxide fillers, Wear, Vol.27, pp. 19-34, 1974. 

[6] Husam .A. Kareem, "study the mechanical properties of polyester resin reinforced by nickel 

powder" MSC.Thesis, Mechanical engineering, university of technology, Iraq-Baghdad, 2008. 

 [7] Haqi I.Gattea, "Effect of particles from magnesium oxide in thermal insulation of conbextra 

epoxy (EP-10) resin", the Iraqi Journal for Mechanical and Material Engineering, Vol.11, No.4, 

2011. 

[8] Amar .J. Bader et.al, "Effect of Alumina particles on the mechanical properties of discontinuous 

glass fiber reinforced unsaturated polyester composites", Al-Qadisiyah Journal for Engineering 

Sciences, Vol. 4, No. 1, 2011.  

[9] Ali Al-Mosawi, "Effect of reinforcing by MgO particles on thermal and mechanical 

characteristics of epoxy resin", The Iraqi Journal for Mechanical and Material Engineering, Vol.11, 

No.3, 2011. 

[10] Ibtihal A. Mahmood, Wafa A. Soud, Orhan S. Abdullah 2013, Effects of Different Types of 

Fillers on Dry Wear Characteristics of Carbon-Epoxy Composite, Al-Khwarizmi Engineering 

Journal, Vol. 9, No. 2, P.P. 85 -93. 

[11] Aseel Mahmood Abdullah, Ahmed Mudhaffer Hashim andAmar Jabar Bader, "effect of 

alumina particles on the mechanical properties of discontinuous glass fiber reinforced unsaturated 

polyester composites", Al-Qadisiyah Journal For Engineering Sciences, Vol. 4, No. 1, 2011. 

[12] N. W. A. Razak, A. Kalam, " Effect of OPEFB Size on the Mechanical Properties and Water 

Absorption Behaviour of OPEFB/PPnanoclay/PP Hybrid Composites", Procedia Engineering, 

vol.41, p.p1593 – 1599, 2012. 

 
Table (1): Physical and mechanical properties of polyester resin. 

Young's 

modulus 

GPa 

Density 

g/cm
3 

Tensile 

Strength 

GPa 

Specific 

heat 

(J/Kg.K) 

Flexural 

strength 

(MPa) 

3 1.09 40 1300 45 

 
Fig. 1: The shape of the mould. 

 
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Fig (2): Standard wear test specimen. 

 
Fig.3: Schematic of pin-on-disc wear testing machine. 

 
      Fig.4: Hardness test device                                Fig.5: Hardness test specimen. 

 
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   Fig.6: Thermal conductivity device        Fig.7: Thermal conductivity specimen 

 
                                    Fig.8: Water absorption specimen. 

 
Fig.9: Effect of weight fraction on wear rate of MgO, CaCO3 and SiO2 composites. 


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Fig.10: Effect of load on wear rate of MgO, CaCO3 and SiO2 composites.  

 
Fig.11: Effect of weight fraction on hardness of MgO, CaCO3 and SiO2 composites. 

 
Fig.12: Effect of weight fraction on thermal conductivity of MgO, CaCO3 and SiO2 

composites. 


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Fig.13: Effect of MgO particles on water absorption. 

 
Fig.14: Effect of SiO2 particles on water absorption. 

 
Fig.15: Effect of CaCO3 particles on water absorption.