UNIVERSITI PUTRA MALAYSIA

FATEMEH MIRJALILI

FK 2010 36

PREPARATION AND CHARACTERIZATION OF α-ALUMINA NANOPARTICLES AND α-ALUMINA-BASED POLYPROPYLENE NANOCOMPOSITES

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PREPARATION AND CHARACTERIZATION OF α-ALUMINA

NANOPARTICLES AND α-ALUMINA-BASED

POLYPROPYLENE NANOCOMPOSITES

By

FATEMEH MIRJALILI

Thesis Submitted to the School of Graduate Studies, University Putra Malaysia,

and Fulfilment of the Requirements for the Degree of Doctor of Philosophy

July 2010

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DEDICATION

Dedicated to:

My beloved family: my mother, my sister and my brother whose constant supports,

unfading love, words of encouragement and patience has always been a great

consolation for me to go through the challenging steps in my life.

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Abstract of thesis presented to the Senate of Universiti of Putra Malaysia in

fulfilment of the requirement for the degree of Doctor of Philosophy

PREPARATION AND CHARACTERIZATION OF α-ALUMINA

NANOPARTICLES AND α-ALUMINA-BASED

POLYPROPYLENE NANOCOMPOSITES

By

FATEMEH MIRJALILI

July 2010

Chairman: Associate Professor Luqman Chuah Abdullah, PhD

Faculty: Engineering

In this study, nano -alumina particles were synthesized by a sol–gel method.

Sodium dodecylbenzen sulfonate (SDBS) and sodium bis-2-ethylhexyl

sulfosuccinate (Na (AOT)) were implemented as the surfactant stabilizing agents.

The prepared solution was, then, stirred at different times (24, 36, 48 and 60 hours)

at 60ºC. SDBS application proved to present a better nanoparticle dispersion and

finer particle size as compared to Na (AOT). The finest particle size ranging from

20-30 nm was obtained at 48 hour stirring time with SDBS surfactant being at

1200°C.

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Similarly, the effect of temperature on production of α- nano alumina was put

under investigation. The process included milling the mediums and uniformly

mixing them with the hydrous alumina during grinding as well as utilizing ZnF2

additives in order to reduce the transformation temperature and to modify the

alumina particles shape. The non agglomerated nano plate like alpha alumina

particles were observed to be formed at their finest size (15-20nm) at 950°C.

Later, self–produced nano -alumina particles were utilized to develop the PP/

nano α-Al2O3 composite. This study aimed to investigate the mechanical, thermal

and morphological properties of PP/ nano α-Al2O3 composite with and without

addition of dispersant. Polypropylene matrix was filled and mixed with different

weight percentages of nano α- alumina particles using a Haake internal mixer.

Mixing was performed at 170ºC and 50 rpm for the rotor speed. Mechanical tests

such as tensile, flexural and Izod impact tests were found to increase by the

addition of content of nano α-Al2O3 as well as the dispersant. Maximum tensile

strength (~16 %) and tensile modulus (~27%) can be attributed to the increase of

nano α-Al2O3 loading from 1 to 4 wt % into PP matrix. Flexural analysis showed

maximum values of 50.5 and 55.88 MPa for flexural strength and 1954 and 2818

MPa for flexural modulus for PP/ nano α-Al2O3 composite with and without

dispersant ,respectively. Notched-Izod impact energy showed an increase up to ~ 43

J/m for the PP/4wt% nano α-Al2O3 composites. Higher concentration of nano α-

Al2O3 loading resulted in a reduction of mechanical properties due to nano α-Al2O3

agglomeration. Dynamic mechanical analysis indicated that the storage and loss

modulus improved with the addition of nano α-Al2O3 loading.

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TGA and DSC analyses were conducted to recognize the thermal behavior of the

composites produced. TGA results illustrated a drastic shift of the weight loss curve

towards higher temperature, which led to reduction in the polypropylene heat

release rate in both composites. DSC results showed that crystallinity of composites

increased with the addition of the Al2O3 nanoparticles. Finally, FTIR study

confirmed the existing of Al-O bond at 568 cm-1 resulted from the nano α-Al2O3

particles which were recently created.

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Abstrak tesis yang dikemukakan kepada Senat Universiti Putra Malaysia

untuk memenuhi keperluan untuk ijazah Doktor Falsafah.

PENYEDIAAN DAN PENCIRIAN PARTIKEL NANO

α-ALUMINA DAN KOMPOSIT POLIPROPELINA NANO

α-ALUMINA

Oleh

FATEMEH MIRJALILI

Julai 2010

Pengerusi: Profesor Madya Luqman Chuah Abdullah, PhD

Fakulti: Kejuteraan

Dalam kajian ini, partikel nano -alumina telah disintesiskan dengan menggunakan

kaedah sol-gel. Natrium dodesil benzene sulfonat (SDBS) dan natrium bis-2-

etilheksil sulfosuksinat (Na (AOT)) telah digunakan sebagai agen penstabilan

surfaktan. Larutan yang telah disediakan kemudian dikacau pada tempoh masa

berbeza (24, 36, 48 dan 60 jam) pada suhu 60 °C. Penggunaan SDBS terbukti

memberikan penyebaran partikel nano yang lebih baik dan saiz partikel yang lebih

halus dibandingkan dengan Na (AOT). Saiz partikel yang paling halus adalah dalam

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lingkungan 20 nm hingga 30 nm telah diperolehi pada 48 jam masa kacau dengan

surfaktan SDBS pada suhu 1200°C.

Kesan suhu ke atas penghasilan partikel nano α- alumina juga telah dikaji. Proses

tersebut melibatkan penggiling yang sederhana dan sekata dengan

mencampurkannya dengan alumina hidrous semasa menggiling untuk menggunakan

aditif ZnF2 supaya dapat mengurangkan tranformasi suhu dan untuk mengubahsuai

bentuk partikel alumina. Partikel nano alfa alumina yang tidak bergumpal dan

berbentuk seperti plat telah diperhatikan berhasil pada saiz yang terhalus (15-20 nm)

pada suhu 950°C.

Kemudian, partikel nano -alumina telah digunakan untuk menghasilkan komposit

PP/ nano α-Al2O3. Kajian ini bertujuan untuk menyiasat sifat-sifat mekanik, terma

dan morfologi komposit PP/ nano α-Al2O3 dengan atau tanpa pertambahan agen

penyerakan. Matrik polipropelina diisikan dan dicampurkan dengan peratusan berat

berbeza partikel nano α- alumina menggunakan sebuah alat pengisar internal

HAAKE. Pencampuran telah dilakukan pada suhu 170ºC dan 50 rpm untuk

kelajuan pemutar. Ujian mekanikal seperti keregangan, lenturan dan hentaman Izod

telah menunjukkan peningkatan dengan pertambahan pemuatan partikel nano α-

Al2O3 dan juga bahan penyerakan. Kekuatan regangan maksimum (~16%) dan

modulus regangan (~27%) adalah dicirikan kepada pertambahan pemuatan partikel

nano α-Al2O3 daripada 1 hingga 4 wt % kedalam matrik PP. Analisis kelenturan

menunjukkan nilai maksimum pada 50.5 dan 55.88 MPa untuk kekuatan lenturan

dan 1954 dan 2818 MPa untuk modulus kelenturan untuk komposit PP/ nano α-

Al2O3 dengan atau tanpa bahan penyerakan. Tenaga untuk ujian hentaman Izod

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menunjukkan peningkatan sehingga ~ 43 J/m untuk komposit PP/ 4wt% nano α-

Al2O3. Kandungan tertinggi α-Al2O3 menunjukkan pengurangan dalam sifat-sifat

mekanikal kerana pengumpalan nano α-Al2O3. Analisis mekanikal dinamik

menunjukkan bahawa modulus storan dan modulus kehilangan meningkat dengan

pertambahan pemuatan nano α-Al2O3.

Analisis TGA dan DSC dijalankan untuk mengenal sifat terma komposit yang

dihasilkan. Keputusan TGA diilustrasikan anjakan mendadak dalam garis

lengkungan kehilangan berat melawan suhu tertinggi, di mana menjuruskan kepada

pengurangan dalam kadar pelepasan haba polipropelina dalam kedua-dua komposit.

Keputusan DSC menunjukkan kehabluran komposit meningkat dengan

pertambahan partikel nano Al2O3. Akhirnya, ujian FTIR mengesahkan kehadiran

ikatan Al-O pada 568 cm-1

menunjukkan partikel nano telah terbentuk.

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ACKNOWLEDGEMENT

My first thanks go to God, the great refuge that everything would happen in his will.

The compilation of this thesis would have, definitely, been impossible without God’s

help.

My sincere appreciation to my supervisor and chair person of the supervisory

committee, Associate Professor Dr. Luqman Chuah Abdullah, who was a great

source of motivation, encouragement and scientific guidance throughout the period

of my study. I am also deeply indebted to him for arranging the necessary funding. I

would like to express my deep thanks to my co-supervisor Dr. Hasmaliza Mohamad

for her sincere endless support and full guidance during the course of this work.

Also, I wish to appreciate Prof. Fakhrul Razi Ahmadun, Dr. Dayang and Dr.

Aghababazadeh as a member of supervisory committee of this thesis. Without them

all, I have no inner strength to face all the challenges and difficulty during the period

of candidature.

I am very much gratified to all the academic staff, technicians, and administrative

staff of the Department of Chemical and Environmental Engineering. My thanks are

also extended to all my friends and colleagues who gave me all kind of support

during my study.

Last but not least, my deepest appreciation and gratitude to my very much dear

mother whose unwavering and unconditional love allowed me to step out to fulfill

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my dream of studying. Their constant spiritual, financial and moral support was

always a great consolation for me.

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I certify that an Examination Committee has met on 15th

July 2010 to conduct the

final examination of Fatemeh Mirjalili on her Doctor of Philosophy thesis entitled

“Production and characterization of nano α- alumina particles and α- alumina

based polypropylene nanocomposites” in accordance with the Universities and

University Colleges Act1971 and the Constitution of the Universiti Putra

Malaysia[P.U.(A)106] 15 March1998. The Committee recommends that the student

be awarded the Doctor of Philosophy.

Members of the Thesis Examination Committee were as follows:

Salmiaton bt.Al, PhD

Associate Professor

Faculty of Engineering

Universiti Putra Malaysia

(Chairman)

Suraya bt.Abdul Rashid, PhD

Lecturer

Faculty of Engineering

Universiti Putra Malaysia

(Internal Examiner)

Aidy b.Ali, PhD

Associate Professor

Faculty of Engineering

Universiti Putra Malaysia

(Internal Examiner)

Hanafi Ismail, PhD

Professor

Faculty of Engineering

Universiti Sians Malaysia

(External Examiner)

BUJANG KIM HUAT , PhD

Professor/Deputy Dean

School of Graduate Studies

Universiti Putra Malaysia

Date:

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This thesis was submitted to the Senate of Universiti Putra Malaysia and has been

accepted as fulfilment of the requirement for the degree of Doctor of Philosophy.

The members of the Supervisory Committee were as follows:

Luqman Chuah Abdullah, PhD

Associate Professor

Faculty of Engineering

Universiti Putra Malaysia

(Chairman)

Fakhru’l-Razi B Ahmadun, PhD

Professor

Faculty of Engineering

Universiti Putra Malaysia

(Member)

Dayang Radiah bt. Awang Biak

Lecturer

Faculty of Engineering

Universiti Putra Malaysia

(Member)

Hasmaliza bt. Mohamad

Lecturer

Faculty of Engineering

Universiti Sians Malaysia

(Member)

Roya Aghababazade

Research Office

Institute for Colorants, Paint and Coatings, Iran

(Member)

HASANAH MOHD GHAZALI, PhD

Professor and Dean

School of Graduate Studies

Universiti Putra Malaysia

Date: 21 October, 2010

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DECLARATION

I declare that the thesis is my original work except for quotation and citations, which

have been duly acknowledged. I also declare that it has not been previously, and it is

not concurrently, submitted for any other degree at University Putra Malaysia or

other institutions.

FATEMEH MIRJALILI

Date: 15 July 2010

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TABLE OF CONTENTS

Page

DEDICATION ii

ABSTRACT iii

ABSTRAK vi

ACKNOWLEDGMENT ix

APPROVAL xi

DECLARATION xiii

LIST OF TABLES xix

LIST OF FIGURES xx

LIST OF ABBREVIATIONS xxvi

CHAPTER

1. INTRODUCTION 1

1.1 General Background 1

1.1.1 Background of the Study 1 1.2 Problem Statement 5

1.3 Objectives of the Study 6 1.4 Scope of the study 7

1.5 Thesis Overview 7

2. LITERATURE REVIEW 9

2.1 Nano Material 9 2.1.1 Alumina 9

2.1.2 Production 11 2.1.3 Properties 11

2.1.4 Applications 12 2.2 Nano Particles 12

2.2.1 Nano α-Al2O3 particles 14

2.2.2 Nano - Al2O3 Fabrication 15 2.2.3 Alumina Sol-Gel 17

2.3 The Effect of Surfactants and Stirring Time for Preparing

Nano α-Al2O3 Particles 18

2.3.1 The Effect of Temperature for Preparing Nano α-Al2O3

Particles 20

2.4 Polymer Matrix Composites (PMC) 23 2.4.1 Introduction of Composites 23

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2.4.2 Classification of Composite 25

2.4.3 Advantages and Disadvantages of Polymer Composites 27 2.4.4 Application of Polymer Composites 29

2.4.5 Particulate Filler Characteristics 31 2.5 Major Component in PMC 33

2.6 Polypropylene 34 2.6.1 Synthesis 34

2.6.2 Filled Polypropylene 36 2.7 Dispersion Behavior of Filler 38

2.8 Method for Preparing PP /Nano α-Al2O3 Composites 40 2.9 Characterization and Properties of Filled Polymer Nano

Composites 41 2.9.1 Mechanical Properties 41

2.9.2 Morphological Properties 44 2.9.3 Thermal Properties 46

3. MATERIALS AND METHODS 51 3.1 Introduction 51

3.2 Materials 52 3.2.1 Aluminum isopropoxide (AlP) 52

3.2.2 Aluminum nitrate nonahydrate (AlN) 53 3.2.3 Sodium bis (2-ethylhexyl) sulfosuccinate (Na(AOT) 53

3.2.4 Sodium dodecylbenzene sulfonate (SDBS) 54 3.2.5 Zinc fluoride (ZnF2) 54

3.2.6 Polypropylene 54 3.2.7 Titanium dioxide 55

3.3 Synthesis of Nano α-alumina Particles 56 3.3.1 Size Controlling of Nano Alpha Alumina Particles 56

3.3.2 Effect of Temperature on Nano Alpha Alumina

Particles 57

3.4 Characterization 58 3.4.1 X-Ray Diffraction (XRD) 59

3.4.2 Scanning Electron Microscope (SEM) 59 3.5 Ultrasonication Treatment of Nano α- Alumina Filler 60

3.6 Compounding and Preparation of PP/ Nano -Al2O3

Composites Samples 61

3.6.1 Melt Compounding of PP/ Nano -Al2O3 Composites

by the Internal Mixer 63

3.6.2 Hot and Cold Compression Molding of PP/ Nano -

Al2O3 Composites 65 3.7 Characterization on the Various Types of Properties for PP/

Nano -Al2O3 Composites 66

3.7.1 Mechanical properties of PP/ Nano -Al2O3

Composites 66

3.7.2 Thermal Properties of Nano Composites 70 3.7.3 Morphological and Microstructure Properties of Nano

Composites 73

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4. PREPARARION OF NANO α-ALUMINA THROUGH THE

SOL-GEL METHOD 78 4.1 Introduction 78

4.2 Synthesis of Nano α-alumina Particles 79 4.2.1 The effect of surfactants and stirring time on size

controlling of nano -Al2O3 Particles 79 4.2.2 Effect of the Temperature on Nano α-Alumina Particles 91

4.2.3 Effect of Dispersant and Ultrasonication on the

Dispersion 98

5. MECHANICALAND MORPHOLOGICAL PEROPERTIES OF

PP/NANO α-Al2O3 COMPOSITES 100

5.1 Effect of Nano Alumina Loading on Mechanical Properties of

PP / Nano α- Al2O3 Composite 100

5.1.1 Introduction 100 5.1.2 Tensile Test 101

5.1.3 Flexural Tests 107 5.1.4 Notched –Izod Impact Strength Analyses for PP / nano

α-Al2O3 Composites 113 5.2 Morphological Analysis of PP/ Nano α-Al2O3 Composites 116

5.2.1 SEM Analysis of Tensile Test Fractured Surface of PP/

Nano α-Al2O3 Composites 116

5.2.2 SEM Analysis of Impact Test Fractured Surface of PP/

Nano α-Al2O3 Composites 128

5.2.3 TEM Analysis of PP/Nano α-Al2O3 Composites 133

6. THERMAL PEROPERTIES OF PP/NANO α-Al2O3

COMPOSITES 139 6.1 Introduction 139

6.2 Thermogravimetry (TGA) Data Analysis for PP/Nano α-Al2O3

Composites 140

6.3 Differential Scanning Calorimetry (DSC) Analysis of PP/Nano

α-Al2O3 Composites 148

6.4 Dynamic Mechanical Analysis (DMA) of PP/ nano α-Al2O3

Composites 156

6.4.1 Storage Modulus (E) of PP/ nano α-Al2O3 Composites 156 6.4.2 Loss Modulus (E”) of PP/ nano α-Al2O3 Composites 160

6.4.3 Damping Factor (tan δ) of PP/ nano α-Al2O3

Composites 162

7. CHARACTERIZATION OF PP/NANO α- Al2O3

COMPOSITES 168 7.1 Introduction 168

7.1.1 Analysis of X-Ray Diffractometry Data for PP/Nano α-

Al2O3 Composites 168

7.1.2 Fourier Transform Infrared (FTIR) Analysis for

PP/Nano α-Al2O3 Composites 173

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8. CONCLUSIONS AND RECOMMENDATIONS FOR

FUTUERE RESEARCH 178 8.1 CONCLUSIONS 178

8.2 Recommendation for Future Research 180

REFERENCES 181

9. BIODATA OF STUDENT 224 10. LIST OF PUBLICATIONS 225