mechanical properties of polypropylene filled with egg shell

�

วารสารวิชาการพระจอมเกล้าพระนครเหนือ ปีที่ 18 ฉบับที่ 3 ก.ย. - ธ.ค. 2551 The Journal of KMUTNB., Vol. 18, No. 3, Sep - Dec. 2008

Mechanical Properties of Polypropylene Filled with Egg Shell

Rapeephun Dangtungee*1 and Sarinya Shawaphun*

บทคัดย่อ งานวิจัยนี้ เป็นการศึกษาสมบัติเชิงกลของผง

เปลือกไข่ซึ่งนำมาเป็นสารเติมแต่งให้กับพลาสติกพอลิพรอพิลีน ผงเปลือกไข่มีส่วนผสมส่วนใหญ่ประกอบไปด้วยแคลเซียมคาร์บอนเนตประมาณ 80 เปอร์เซ็นต์โดยทำการทดลองเปรยีบเทยีบกบัสารแคลเซยีมคารบ์อนเนต การเตรียมพลาสติกผสมใช้เครื่องผสมแบบเกลียวคู่ผสมเปลือกไข่และแคลเซียมคาร์บอนเนตที่อัตราส่วนผสม 5 ถึง 30 เปอร์เซ็นต์โดยน้ำหนักและนำไปฉีดขึ้นรูปด้วยเครื่องฉีดขึ้นรูปชิ้นงานจากนั้นนำไปทดสอบแรงดึง แรงกระแทก และดูลักษณะทางกายภาพด้วยกล้องอิเล็กตรอนแบบส่องกราด ผลการทดลองพบว่าค่าความเค้นแรงดึงของพลาสติกผสมมีค่าลดลงเมื่อเพิ่มปริมาณเปลือกไข่และแคลเซียมคาร์บอนเนต ค่ายังมอดลูสัมคีา่เพิม่ขึน้ตามปรมิาณการเตมิสารเตมิแตง่ทัง้คู ่และพบว่าสารเติมแต่งที่ทำการเคลือบผิวด้วยกรด สเตียริกมีค่าความเค้นแรงดึงต่ำกว่าสารเติมแต่งที่ไม่เคลือบผิวเล็กน้อย ในขณะที่ผลการทดลองการต้านทานแรงกระแทกพบว่าพลาสติกผสมสารเติมแต่งทั้งสองมีความต้านทานแรงกระแทกเพิ่มมากขึ้นตามปริมาณ สารเตมิแตง่ทีเ่ตมิลงไปและสารเตมิแตง่ทีท่ำการเคลอืบผวิ ด้วยกรดสเตียริกมีค่าความต้านทานแรงกระแทกได้ดีกว่าต่ำกว่าสารเติมแต่งที่ไม่เคลือบผิว ผลการทดลอง ชี้ ให้เห็นว่าเปลือกไข่สามารถเป็นสารเติมแต่งของพลาสติกพอลิพรอพิลีนได้ดีเทียบเท่ากับแคลเซียม

คาร์บอนเนต และการเคลือบผิวของสารเติมแต่งมีผลทำให้การกระจายตัวของสารเติมแต่งในเนื้อพอลิเมอร์ ดีขึ้น

Abstract

Egg shell powder has been used as a filler for

reinforcing thermoplastic, isotactic polypropylene

(iPP). Egg shell powder composed of about 80% of

CaCO3 and the left contains small amount of lipid

and protein. The PP-Egg shell and CaCO3

composites were prepared by twin screw extruder

and injection molding machine. The mechanical

properties of the composites were studied by tensile

tester, impact tester and scanning electron

microscope (SEM). Isotactic polypropylene

compounded with uncoated and stearic acid-coated

CaCO3 and egg shell particles in various filler

loadings, ranging from 5 to 30 wt.%. The tensile

stress for both compounds was found to decrease

with increasing amounts of filler. The young’s

modulus result was found the modulus increased

with increasing amount of fillers. Coated fillers gave

a little lower stress and young’s modulus than

uncoated. An increase in both fillers, over all the

impact strength was increased. The coated filler

* Lecturer, Department of Industrial Chemistry, Faculty of Applied Science, King Mongkut’s University

of Technology North Bangkok. 1 Author to whom correspondence should be addressed (02�132500 ext 4825; E-mail: [email protected])

10


exhibited greater strength than another uncoated for

both CaCO3 and egg shell fillers. Lastly, the egg

shell fillers not only can be replaced CaCO3 filler

but they also quite improved the impact strength.

And, the coated surface of filler associated with the

dispersion and distribution of filler.

Keywords: Polymer Composites, Calcium Carbonate,

Mechanical Properties, Filler, Egg

Shell, Impact Strength

1. Introduction

Nowadays, inorganic fillers play an important

role in plastics industry. The purposes of their use

do not only confine to the cost reduction, but to

improve mechanical performance like rigidity,

dimensional stability, toughness, and transparency

[1], [2] as well. The level of such improvement

depends significantly upon type, size and shape,

content, and surface treatment of the fillers [3]-[5].

The latter determines the interaction between the

polymer matrix and the fillers at the interface.

Among the various mineral fillers, calcium

carbonate (CaCO3) has been the most utilized

material, due partly to its availability and low cost

[6]. Egg shell powder was a natural material that

consists of inorganic fillers as �0% calcium

carbonate approximately [7].

Not only the presence but also the distribution

of the fillers affects a great deal the viscoelasticity

of the polymer matrix. The distribution of the filler

within the polymer matrix can be improved by

surface treatment with a dispersant, e.g. stearic acid,

which helps reduce the viscosity of the matrix and,

to some extent, prevent the fillers from forming a

network [1], [8], [�].

Thio et al. [1] investigated the toughening of

isotactic polypropylene (iPP) filled with CaCO3

particles of varying average diameters (i.e. 0.07, 0.7,

and 3.5 μm). In slow tension, addition of fillers

increased the modulus and decreased the yield

stress, irrespective of the filler type used. The strain

at break was found to increase with initial

incorporation of filler, but it was found to decrease

at higher loadings. Chan et al. [4] studied

crystallization and mechanical properties of iPP

filled with CaCO3 particles having the average

diameter of ca. 44 nm. They found that CaCO3

nanoparticles were an effective nucleating agent for

iPP. The modulus was found to increase by ca. 85%,

while the impact strength was found to improve by

ca. 300%, from that of neat iPP. The effect of

addition of talcum and CaCO3 particles on

mechanical and rheological properties of iPP was

reported by da Silva et al. [2]. They found that

marked improvement in the modulus, tensile stress

at break, and yield stress was observed for talcum-

filled iPP. Addition of the fillers enhanced the

impact strength, but, with increasing filler content,

the impact strength was found to decrease.

Though not totally relevant, Supaphol et al.

[10] investigated the effects of CaCO3 of varying

particle size (i.e. 1.�, 2.8 and 10.5 μm), content (i.e.

0 to 40 wt.%), and type of surface modification (i.e.

uncoated, stearic acid-coated, and paraffin-coated)

on crystallization and melting behavior, mechanical

properties, and processability of CaCO3-filled

syndiotactic polypropylene (sPP). It was found that

CaCO3 was a good nucleating agent for sPP. The

nucleating efficiency of CaCO3 for sPP depended

strongly on its purity, type of surface treatment, and

average particle size. Tensile strength was found to

11


decrease, while Young’s modulus was found to

increase, with increasing Ca Both types of surface

treatment on CaCO3 particles helped improve

particle distribution, hence impact resistance.

Steady-state shear viscosity of CaCO3–filled sPP

was found to increase with increasing CaCO3

content and decreasing particle size.

In this paper focuses on mechanical properties

of isotactic polypropylene (iPP) compounded with

egg shell and CaCO3 particles having the mean

particle size of ca. 60 μm respectively. In order to

natural material and waste by product, egg shell

could be selected for substitute the CaCO3 particles

for economic reason. Also, the particle size of ca. 60 μm,

for using in this work, is the mainly cause on easily

preparation and cost for operation. The effects of

content (i.e. 5, 10, 20 and 30 wt.%) and surface

modification (i.e. neat and stearic acid-coated) of

the filler on such properties were thoroughly

investigated using a tensile tester, impact tester and

scanning electron microscope (SEM).

2. Experimental Details

2.1 Materials

A commercial grade of polymer resin of iPP

(1100NK) used in this study was supplied by Thai

Petrochemical Industry Public Company Limited

Co., Ltd. (Cholburi, Thailand). Certain properties of

the resin, provided by the manufacturer, are as

follows: MFR (2.16 kg at 230°C) = 11 g (10 min)-1,

tensile strength at yield = 36 MPa, elongation at

yield = 26%, flexural modulus = 1500 MPa, and

notched Charpy impact strength at 23°C = 2.� mJ. mm-1.

CaCO3 (analytical grade) was supplied by MERCK

Thailand that average (primary) particle size = 60

μm, and particle shape = cubic. The egg shell (hen)

was supplied by CPF feeds PLC. (Thailand). All of

shells have been first prepared by drying at 80oC on

2 hours. Then, the shell was grinding and sieving

(sieve analysis 60 μm) at room temperature. Partiall

y, egg shell and CaCO3 were modified with stearic

acid to facilitate particle dispersion and distribution

within the matrix as follow: 71.11g of stearic

acid was diluted in 1000 ml butanol and stirred.

Then, 8.33g of egg shell was added. The

composition was waiting for 24 hr., drying, and

lastly grinding.

2.2 Compounding

CaCO3 and egg shell were first dried in an

oven at 80oC for 24 hours and then pre-mixed with

iPP pellets in a tumble mixer for 15 minutes in

various compositional ratios (i.e. 5, 10, 20 and 30

wt.%). The pre-mixed compounds were then fed

into a BETOL 2525 co-rotating twin-screw extruder

operating at a screw speed of 60 rpm and a

temperature profile of 230 (die), 230 (metering

zone), 210 (compression zone) and 1�0oC (feed zone).

The extrudate was cooled in water and cut into

pellet form. All of samples in various compositional

ratios were molding in ENGEL injection molding

operating at 100 bar for injection pressure and

235oC on nozzle temperature.

2.3 Mechanical Testing and Imaging

A LLOYD LR 10 K tensile tester was used to

measure tensile stress and young’s modulus

following ASTM D 638-�4b. The impact resistance

property was measured by YASUDA impact tester

following ASTM D 256-�3a. Lastly, the JOEL JSM

5200 scanning electron microscope was used to

investigate the image of fillers on the iPP matrix.

12


10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40

Filler (%wt)

Ten

sile

str

ess

(kN

/m2)

caco3

egg shell

Figure 2. Comparison tensile stress on amount of fillers for iPP filled stearic acid-coated CaCO3 and egg shell.

3. Results and Discussion

Dependence of stress on amount of filler for

iPP filled both uncoated and stearic acid-coated

CaCO3 and egg shell is illustrated in Figure 1a and

1b. Apparently, within amounts of filler range

investigated (i.e. 5 to 30 wt %), both iPP compounds

exhibited and decrease in the stress value with

increasing amounts of fillers. The results could be

described on the ability to receive a stretching force.

The insertion of filler between molecular chains of

polymer is affect to intermolecular force and loosely

chain entanglement. Comparatively, the result of

CaCO3 and egg shell on tensile stress is showed in

figure 2. Tensile stress are not different as much at

low amount of fillers (i.e. 5-10 wt %). But, in case

of higher amount of fillers (i.e. 15-30 wt %) egg

shell composites exhibited lower stress than another.

It may be effect on the other compositions as other

type and shapes in egg shell on stretching force.

Intern, young’s modulus is showed in figure 3a and

3b. The modulus result was found the modulus

increased with increasing amount of fillers. Young’s

modulus is a linear ratio of stress and strain before

the occurrence of plastic region. An increase in

modulus may be the filler which inserting on the

polymer chain has more effective on the stain or

stretching in axial direction of the chain.

Comparatively, coated fillers gave a little lower

Figure 1 Dependence of stress on amount of fillers

for iPP filled both uncoated and stearic

acid-coated (a) CaCO3 and (b) egg shell.

(a)

(b) Figure 1 Dependence of stress on amount of fillers

for iPP filled both uncoated and stearic acid-coated (a) CaCO3 and (b) egg shell.

3. Results and Discussion Dependence of stress on amount of filler for iPP

filled both uncoated and stearic acid-coated CaCO3

and egg shell is illustrated in Figure 1a and 1b.Apparently, within amounts of filler range investigated (i.e. 5 to 30 wt %), both iPP compounds exhibited and decrease in the stress value with increasing amounts

10

20

30

40

0 510152025303540

Filler (%wt)

Ten

sile

str

ess

(kN

/m2)

caco3

eggshell

Figure 2 Comparison tensile stress on amount of fillers for iPP filled stearic acid-coated CaCO3 and egg shell.

of fillers. The results could be described on the ability to receive a stretching force. The insertion of filler between molecular chains of polymer is affect to intermolecular force and loosely chain entanglement. Comparatively, the result of CaCO3 and egg shell on tensile stress is showed in figure 2. Tensile stress are not different as much at low amount of fillers (i.e. 5-10 wt %). But, in case of higher amount of fillers (i.e. 15-30 wt %) egg shell composites exhibited lower stress than another. It may be effect on the other compositions as other type and shapes in egg shell on stretching force. Intern, young’s modulus isshowed in figure 3a and 3b. The modulus result was found the modulus increased with increasing amount of fillers. Young’s modulus is a linear ratio of stress and strain before the occurrence of plastic region. An increase in modulus may be the filler which inserting on the polymer chain has more effective on the stain or stretching in axial direction of the chain. Comparatively, coated fillers gave a little lower stress and young’s modulus than uncoated. Due to the good dispersion and distribution of filler, the loosely chain and the decreasing of intermolecular force was appearance.

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40

Uncoated

Coated

Filler (%wt)

Tens

ile S

tress

(kN

/m2 )

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40Filler (%wt)

Tens

ile S

tress

(kN

/m2 )

Uncoated

Coated

Figure 2 Comparison tensile stress on amount of

fillers for iPP filled stearic acid-coated

CaCO3 and egg shell.

(a) (a)

(b) Figure 1 Dependence of stress on amount of fillers

for iPP filled both uncoated and stearic acid-coated (a) CaCO3 and (b) egg shell.

3. Results and Discussion Dependence of stress on amount of filler for iPP

filled both uncoated and stearic acid-coated CaCO3

and egg shell is illustrated in Figure 1a and 1b.Apparently, within amounts of filler range investigated (i.e. 5 to 30 wt %), both iPP compounds exhibited and decrease in the stress value with increasing amounts

10

20

30

40

0 510152025303540

Filler (%wt)

Ten

sile

str

ess

(kN

/m2)

caco3

eggshell

Figure 2 Comparison tensile stress on amount of fillers for iPP filled stearic acid-coated CaCO3 and egg shell.

of fillers. The results could be described on the ability to receive a stretching force. The insertion of filler between molecular chains of polymer is affect to intermolecular force and loosely chain entanglement. Comparatively, the result of CaCO3 and egg shell on tensile stress is showed in figure 2. Tensile stress are not different as much at low amount of fillers (i.e. 5-10 wt %). But, in case of higher amount of fillers (i.e. 15-30 wt %) egg shell composites exhibited lower stress than another. It may be effect on the other compositions as other type and shapes in egg shell on stretching force. Intern, young’s modulus isshowed in figure 3a and 3b. The modulus result was found the modulus increased with increasing amount of fillers. Young’s modulus is a linear ratio of stress and strain before the occurrence of plastic region. An increase in modulus may be the filler which inserting on the polymer chain has more effective on the stain or stretching in axial direction of the chain. Comparatively, coated fillers gave a little lower stress and young’s modulus than uncoated. Due to the good dispersion and distribution of filler, the loosely chain and the decreasing of intermolecular force was appearance.

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40

Uncoated

Coated

Filler (%wt)

Tens

ile S

tress

(kN

/m2 )

10

15

20

25

30

35

40

0 5 10 15 20 25 30 35 40Filler (%wt)

Tens

ile S

tress

(kN

/m2 )

Uncoated

Coated

(b)

13


300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40Filler (%wt)

Yo

un

g's

mo

du

lus

(M

Pa

)

Uncoated

Coated

(a)

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Yo

un

g's

mo

du

lus

(MP

a)

Uncoated

Coated

Figure 3 Young’s modulus is a function of amount of fillers for iPP filled both uncoated and stearic acid-coated (a.) CaCO3 and (b.) egg shell.

According to Figure 4a and 4b, the impact strength at a given amounts of filler for iPP filled both uncoated and stearic acid-coated CaCO3 and egg shell. Apparently, an increase in both fillers, over all the impact strength was increased. The coated filler exhibited greater strength than another uncoated for both CaCO3 and egg shell fillers. Due to coating with stearic acid on the surface of filler, tend to better dispersion and distribution of filler, the absorption of shock load or impact force could be greater. Interestingly, at high amount of filler (20-30 wt %)

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated

(a)

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated

(b) Figure 4 The impact strength at a given amounts of

filler for iPP filled both uncoated and stearic acid-coated (a.) CaCO3 and (b.) egg shell.

(see figure 4a.), the impact strength tend to decrease. But, in case of coated fillers are disappeared, which the strength gradually increased. The result can be suggested that at high amount of uncoated CaCO3

the agglomerate of CaCO3 was easily occurred. So, the reduction of the dissipated CaCO3 particles is affecting the impact strength. Relatively, the eggshell filler (see figure 4b.) present similarly behavior. Figure 5 shows impact strength as a function of filler

stress and young’s modulus than uncoated. Due to

the good dispersion and distribution of filler, the

loosely chain and the decreasing of intermolecular

force was appearance.

According to Figure 4a and 4b, the impact

strength at a given amounts of filler for iPP filled

both uncoated and stearic acid-coated CaCO3 and

egg shell. Apparently, an increase in both fillers,

over all the impact strength was increased. The

coated filler exhibited greater strength than another

uncoated for both CaCO3 and egg shell fillers. Due

to coating with stearic acid on the surface of filler,

tend to better dispersion and distribution of filler,

the absorption of shock load or impact force could

be greater. Interestingly, at high amount of filler (20-

30 wt %) (figure 4a.), the impact strength tend to

decrease. But, in case of coated fillers are

disappeared, which the strength gradually increased.

The result can be suggested that at high amount of

Figure 3 Young’s modulus is a function of

amount of fillers for iPP filled both

uncoated and stearic acid-coated (a.)

CaCO3 and (b.) egg shell.

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40Filler (%wt)

Yo

un

g's

mo

du

lus

(M

Pa

)

Uncoated

Coated

(a)

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Yo

un

g's

mo

du

lus

(MP

a)

Uncoated

Coated



0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated

(a)

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated





300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40Filler (%wt)

Yo

un

g's

mo

du

lus

(M

Pa

)

Uncoated

Coated

(a)

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Yo

un

g's

mo

du

lus

(MP

a)

Uncoated

Coated



0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated

(a)

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated





Figure 4 The impact strength at a given amounts

of filler for iPP filled both uncoated and

stearic acid-coated (a.) CaCO3 and (b.)

egg shell.

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40Filler (%wt)

Yo

un

g's

mo

du

lus

(M

Pa

)

Uncoated

Coated

(a)

300

400

500

600

700

800

900

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Yo

un

g's

mo

du

lus

(MP

a)

Uncoated

Coated



0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated

(a)

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler ( %wt )

Imp

act

(kJ/

m2)

Uncoated

Coated





(a) (a)

(b)

14


uncoated CaCO3 the agglomerate of CaCO3 was

easily occurred. So, the reduction of the dissipated

CaCO3 particles is affecting the impact strength.

Relatively, the eggshell filler (figure 4b.) present

similarly behavior. Figure 5 shows impact strength

as a function of filler loading for all of CaCO3 and

egg shell filler. Apparently, impact strength of both

fillers has been significant. The egg shell fillers not

only can be replaced CaCO3 filler but they also quite

improved the impact strength. And, the coated

surface of filler associated with the dispersion and

distribution of filler. Figure 6a. and 6b. showed the

SEM photograph of 20 wt% of egg shell filled in

iPP matrix. Comparatively, the particle size of filler

showed a noticeable difference. Uncoated filler shows

the agglomerate particle. But, it was found to decrease

in coated fillers. These figures are supporting the

result of dispersion and distribution of filler.

4. Conclusion

In the present contribution, mechanical

property of isotactic polypropylene (iPP)

compounded with uncoated and stearic acid-coated

CaCO3 and egg shell particles in various filler

loadings, ranging from 5 to 30 wt.%. The stress for

both compounds was found to decrease with

increasing amounts of filler. The young’s modulus

was found the modulus increased with increasing

amount of fillers. Coated fillers gave a little lower

stress and young’s modulus than uncoated. Due to

the good dispersion and distribution of filler, the

loosely chain and the decreasing of intermolecular

force was appearance. The impact strength of both

fillers has been significant. An increase in both

Figure 5 Impact strength as a function of filler

loading for all of CaCO3 and egg shell filler.

Figure 6 The SEM photograph of 20 wt% of egg

shell filled in iPP matrix (a.) Coated

egg shell (b.) Uncoated egg shell.

loading for all of CaCO3 and egg shell filler. Apparently, impact strength of both fillers has been significant. The egg shell fillers not only can be replaced CaCO3 filler but they also quite improved the impact strength. And, the coated surface of filler associated with the dispersion and distribution of filler. Figure 6a. and 6b. showed the SEM photograph of 20 wt% of egg shell filled in iPP matrix. Comparatively, the particle size of filler showed a noticeable difference. Uncoated filler shows the agglomerate particle. But, it was found to decrease in coated fillers. These figures are supporting the result of dispersion and distribution of filler.

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler (%wt)

Imp

act

Str

eng

th(k

J/m

2)

CaCO3 coated

Egg shell coated

CaCO3 uncoated

Egg shell uncoated

Figure 5 Impact strength as a function of filler loading for all of CaCO3 and egg shell filler.

(a)

(b) Figure 6 The SEM photograph of 20 wt% of egg shell

filled in iPP matrix (a.) Coated egg shell (b.) Uncoated egg shell.

4. Conclusions In the present contribution, mechanical property

of isotactic polypropylene (iPP) compounded with uncoated and stearic acid-coated CaCO3 and egg shell particles in various filler loadings, ranging from 5 to 30 wt.%. The stress for both compounds was found to decrease with increasing amounts of filler. The young’s modulus was found the modulus increased with increasing amount of fillers. Coated fillers gave a little lower stress and young’s modulus than uncoated. Due to the good dispersion and distribution of filler, the loosely chain and the

loading for all of CaCO3 and egg shell filler. Apparently, impact strength of both fillers has been significant. The egg shell fillers not only can be replaced CaCO3 filler but they also quite improved the impact strength. And, the coated surface of filler associated with the dispersion and distribution of filler. Figure 6a. and 6b. showed the SEM photograph of 20 wt% of egg shell filled in iPP matrix. Comparatively, the particle size of filler showed a noticeable difference. Uncoated filler shows the agglomerate particle. But, it was found to decrease in coated fillers. These figures are supporting the result of dispersion and distribution of filler.

0

1

2

3

4

5

6

7

8

9

0 5 10 15 20 25 30 35 40

Filler (%wt)

Imp

act

Str

eng

th(k

J/m

2)

CaCO3 coated

Egg shell coated

CaCO3 uncoated

Egg shell uncoated

Figure 5 Impact strength as a function of filler loading for all of CaCO3 and egg shell filler.

(a)

(b) Figure 6 The SEM photograph of 20 wt% of egg shell

filled in iPP matrix (a.) Coated egg shell (b.) Uncoated egg shell.

4. Conclusions In the present contribution, mechanical property

of isotactic polypropylene (iPP) compounded with uncoated and stearic acid-coated CaCO3 and egg shell particles in various filler loadings, ranging from 5 to 30 wt.%. The stress for both compounds was found to decrease with increasing amounts of filler. The young’s modulus was found the modulus increased with increasing amount of fillers. Coated fillers gave a little lower stress and young’s modulus than uncoated. Due to the good dispersion and distribution of filler, the loosely chain and the

15


fillers, over all the impact strength was increased.

The coated filler exhibited greater strength than

another uncoated for both CaCO3 and egg shell

fillers. Lastly, the egg shell filler not only can be

replaced CaCO3 filler but they also quite improved

the impact strength. And, the coated surface of filler

associated with the dispersion and distribution of filler.

5. Acknowledgments

Partial supports received from Department of

Industrial Chemistry, Faculty of Applied Science,

King Mongkut’s University of Technology North

Bangkok and from The science and Technology

Research Institute, King Mongkut’s University of

Technology North Bangkok are gratefully

acknowledged.

References

[1] Y.S. Thio, A.S. Argon, R.E. Cohen and M.

Weinberg, Polymer, vol. 43, pp. 3661, 2002.

[2] A.L.N. da Silva, M.C.G. Rocha, M.A.R.

Moraes, C.A.R. Valente and F.M.B. Coutinho,

Polymer Testing, vol. 21, pp. 57, 2002.

[3] A. Tabtiang and R. Venables, European

Polymer Journal, vol. 36, pp. 137, 2000.

[4] C.M. Chan, J.S. Wu, J.X. Li and Y.K. Cheung,

Polymer, vol.43, pp. 2�81, 2002.

[5] J. Gonzalez, C. Albano, M. Ichazo and B. Diaz,

European Polymer Journal, vol.38, pp. 2465,

2002.

[6] S. Miao, Applied Surface Science, vol. 220, pp.

2�8, 2003.

[7] Ken W. Koelkebeck, “What is Egg Shell

Quality and How to Preserve It,” [Online].

Available: http://ag.ansc.purdue.edu/poultry/

multistate/koelkebeck1.htm

[8] G. Nowaczyk, S. Glowinkowski and S. Jurga,

Solid State Nuclear Magnetic Resonance, vol.

25, pp. 1�4, 2004.

[�] B. Haworth, S. Jumpa and N.A. Miller,

Polymer Testing, vol.1�, pp.45�, 2000.

[10] P. Supapho, W. Harnsiri and J. Junkasem,

Journal of Applied Polymer Science, vol. �2,

pp. 201, 2004.

mechanical properties of polypropylene filled with egg shell

Documents