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UNIVERSITI TEKNIKAL MALAYSIA MELAKA A Comparison of Mechanical Properties between Kenaf Core Fiber and Kenaf Bast Fiber Reinforced Polyester Composites Thesis submitted in accordance with the partial requirements of the Universiti Teknikal Malaysia Melaka for the Degree of Bachelor of Engineering (Honours) Manufacturing (Process) By Mohamad Ridzwan Bin Ishak Faculty of Manufacturing Engineering May 2007

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Page 1: A COMPARISON OF MECHANICAL PROPERTIES BETWEEN KENAF CORE ...eprints.utem.edu.my/7331/1/A_Comparison_Of... · A Comparison of Mechanical Properties between Kenaf Core Fiber and Kenaf

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

A Comparison of Mechanical Properties between Kenaf Core Fiber and Kenaf Bast

Fiber Reinforced Polyester Composites

Thesis submitted in accordance with the partial requirements of the

Universiti Teknikal Malaysia Melaka for the Degree of Bachelor

of Engineering (Honours) Manufacturing (Process)

By

Mohamad Ridzwan Bin Ishak

Faculty of Manufacturing Engineering

May 2007

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UTeM Library (Pind.1/2005)

SULIT

TERHAD

TIDAK TERHAD

(Mengandungi maklumat yang berdarjah keselamatan atau kepentingan Malaysia yang termaktub di dalam AKTA RAHSIA RASMI 1972)

(Mengandungi maklumat TERHAD yang telah ditentukan oleh organisasi/badan di mana penyelidikan dijalankan)

(TANDATANGAN PENULIS)

Alamat Tetap: No. 2A, Jalan Cacar, Kg. Kuala Jempol, 72100 Bahau, N. Sembilan. Tarikh: _______________________

Disahkan oleh:

(TANDATANGAN PENYELIA)

Cop Rasmi:

Tarikh: _______________________

* Tesis dimaksudkan sebagai tesis bagi Ijazah Doktor Falsafah dan Sarjana secara penyelidikan, atau disertasi bagi pengajian secara kerja kursus dan penyelidikan, atau Laporan Projek Sarjana Muda (PSM). ** Jika tesis ini SULIT atau TERHAD, sila lampirkan surat daripada pihak berkuasa/organisasi berkenaan dengan menyatakan sekali sebab dan tempoh tesis ini perlu dikelaskan sebagai SULIT atau TERHAD.

BORANG PENGESAHAN STATUS TESIS*

JUDUL: A COMPARISON OF MECHANICAL PROPERTIES BETWEEN KENAF CORE

FIBER AND KENAF BAST FIBER REINFORCED POLYESTER COMPOSITE SESI PENGAJIAN: 2/2006-2007 Saya _____________________________________________________________________ mengaku membenarkan tesis (PSM/Sarjana/Doktor Falsafah) ini disimpan di Perpustakaan Universiti Teknikal Malaysia Melaka (UTeM) dengan syarat-syarat kegunaan seperti berikut:

1. Tesis adalah hak milik Universiti Teknikal Malaysia Melaka. 2. Perpustakaan Universiti Teknikal Malaysia Melaka dibenarkan membuat salinan

untuk tujuan pengajian sahaja. 3. Perpustakaan dibenarkan membuat salinan tesis ini sebagai bahan pertukaran

antara institusi pengajian tinggi. 4. **Sila tandakan (√)

MOHAMAD RIDZWAN BIN ISHAK

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

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APPROVAL

This thesis submitted to the senate of UTeM and has been accepted as partial fulfillment

of the requirements for the degree of Bachelor of Manufacturing Engineering

(Manufacturing Process). The members of the supervisory committee are as follow:

…………………………………………

Main Supervisor

(Official Stamp and Date)

………………………………………..

Co – Supervisor

(Official Stamp and Date)

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DECLARATION

I hereby, declared this thesis entitled “A Comparison of Mechanical Properties between

Kenaf Core Fiber and Kenaf Bast Fiber Reinforced Polyester Composites.” is

the results of my own research except as cited in references

Signature : …………………………………………

Author’s Name : …………………………………………

Date : …………………………………………

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ABSTRACT

The purpose of doing this project is to study the comparison of mechanical properties

and microstructure between kenaf core fiber and kenaf bast fiber reinforced polyester

composites. The matrix material used in this study was based on commercially available

unsaturated polyester, obtained from university’s Polymer Lab. The matrix was mixed

with curing catalyst, methyl ethyl ketone peroxide (MEKP) Butanox M50 at a

concentration of 0.01 w/w of the matrix for curing. Short kenaf bast and core fibers were

separated from mixture bast and core fibers using vibratory screen machine in Wooden

Composite Lab, for used as the reinforcement and were provided by Forest Research

Institute of Malaysia (FRIM). A combination of hand lay-up and compression moulding

method was used to prepare the kenaf fiber reinforce polyester composite specimens.

Moist kenaf bast and core fiber was first dried at 80 °C for 1.5 hours to remove storage

moisture in an oven and some of the kenaf bast fibers are left to moist in order to

investigate the effect of the moisture fiber composite specimens to the mechanical

properties. The mould was coated with a plastic, sprayed with silicone mould release

agent and subsequently coated with gelcoat. After pouring the resin, trapped air was

gently squeezed out using a roller. The kenaf fiber and polyester resin were then left for

about 3 min to allow air bubbles to escape from the surface of the resin. The mould was

closed and the composite panel was left to cure in a hydraulic press at a temperature of

25 °C and at a compaction pressure of 10 bars for 24 hours. After being taken out from

the hydraulic press, the panel being removed from the mould and was left to fully dry at

a temperature of 25 °C for 2 weeks. Subsequently, the panel composites were cut to

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desired dimension of specimen follows the ASTM standard. The randomly oriented bast

and core fiber 5% – 40 % fiber volume fraction and unfilled composite were used to

prepare using similar procedure for comparison purpose. The sizes of bast and core

fibers used were found that 39.41µm and 563.6 µm respectively using Scanning

Electron Machine (SEM) from Zeiss, model EVO 50. The specimens were tested for

tensile, flexural, impact and provide the result as totally the kenaf bast fiber indicates the

higher strength, the exposure to moisture results in significant drops in tensile, flexural

and impact properties due to the degradation of the fiber–matrix interface. The core fiber

is found lead in high absorbent rate due their geometry structural after being water

absorption test. SEM analysis for surface topography found that the clean surface of bast

and non-uniform in term of fiber shape and size of core fiber.

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ABSTRAK

Projek ini adalah bertujuan untuk mengkaji perbandingan sifat mekanikal dan

mikrostruktur di antara gentian daripada kulit dan empulur pokok kenaf diperkuatkan

dengan termoset poliester komposit. Matrik yang akan digunakan adalah matrik daripada

jenis polimer termoset iaitu poliester yang diperolehi dari Makmal Polimer universiti.

Termoset poliester dicampur dengan pemangkin metil etil keton peroksida (MEKP)

Butanox M50 dengan nisbah berat satu bahagian daripada seratus berat poliester bagi

tujuan proses pengerasan komposit. Gentian daripada kulit dan empulur kenaf telah

dibekalkan oleh Institut Penyelidikan Perhutanan Malaysia (FRIM), Kepong, Kuala

Lumpur setelah dipisahkan dengan menggunakan ‘Vibratory Screen Machine’ di

Makmal Komposit Kayu, FRIM. Gentian telah dikeringkan di dalam oven selama satu

setengah jam pada suhu 80 °C manakala sebahagian gentian daripada kulit kenaf

dibiarkan tanpa proses pengeringan bagi menguji kesan kelembapan gentian kepada sifat

mekanikal berbanding gentian yang telah dikeringkan. Pengacuan terbuka telah dibuat

daripada kepingan besi bergalvani bagi tujuan penghasilan spesimen setelah acuan

daripada acrylic, keluli lembut didapati gagal menghasilkan spesimen yang dikehendaki.

Bagi ujian mekanikal, piawaian yang dirujuk ialah ASTM D5083 bagi ujian tegangan,

ASTM D790 bagi ujian kelenturan dan ASTM D256 bagi ujian hentaman jenis

‘Charpy’. Kombinasi di antara kaedah bengkalai tangan dan kaedah mampatan tuangan

telah digunakan bagi menghasilkan spesimen komposit gentian daripada kulit dan

empulur kenaf diperkuat termoset poliester. Komposit dimampatkan pada tekanan 10

Bar pada suhu bilik dan dibiarkan mengeras selama 24 jam. Setelah dikeluarkan

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daripada acuan, panel komposit dibiarkan pada suhu bilik selama 2 minggu bagi

memastikan komposit kering sepenuhnya sebelum dipotong mengikut dimensi ukuran

piawaian ASTM. Prosedur yang sama telah dijalankan bagi menghasilkan komposit

gentian daripada kulit dan empulur kenaf diperkuat poliester dengan pertambahan

peratusan berat pengisi bagi kedua-dua gentian. Komposit yang dihasilkan adalah 5%,

10%, 20%, 30%, 40% berat pengisi gentian dan komposit tanpa pengisi. Berdasarkan

eksperimen, peratusan maksimum berat gentian kenaf yang boleh diisi adalah sebanyak

40% berdasarkan sifat resapan cecair semulajadi bahan. Ujian mekanikal telah

dijalankan dan mendapati gentian daripada kulit kenaf diperkuat poliester memberikan

nilai kekuatan tegangan, kelenturan dan hentaman lebih tinggi. Komposisi terbaik bagi

menghasilkan nilai kekuatan tertinggi untuk gentian daripada kulit kenaf adalah sekitar

10%-20% manakala gentian daripada empulur kenaf adalah sekitar 5%-20% berat

pengisi. Kelembapan gentian didapati mengurangkan sifat mekanikal gentian. Analisis

topografi menggunakan Scanning Electron Microscope (SEM) keluaran Syarikat Zeiss,

model EVO 50 mendapati keadaan permukaan gentian daripada kulit kenaf yang lebih

halus dengan purata diameter 39.41µm manakala gentian daripada empulur kenaf

mempunyai permukaan agak kasar, berlubang-lubang dan mempunyai bentuk yang tidak

seragam dengan purata diameter yang lebih besar iaitu 563.6 µm. Berdasarkan struktur

geometri gentian daripada empulur kenaf, kadar resapan cecair didapati lebih tinggi

berbanding gentian daripada kulit kenaf setelah ujian resapan air dijalankan..

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DEDICATION

For all your advice and encouragement, this thesis is gratefully dedicated to my family

and my friends. Thank you very much for your continuous support and effort towards

the publication of this thesis.

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ACKNOWLEDGEMENT

I would like to express my appreciation to the individuals who had played a part in

ensuring a successful occurrence and flow of activities throughout the duration of my

final year project. Endless appreciation and gratitude to my supervisor, Mr. Edeerozey

Abd. Manaf and to my second examiner Mrs. Intan Sharhida Othman for their

encouragement and support and for spending quite some time with myself, providing a

lot of guidance and ideas for my project research. Their knowledge and experience

really inspired and spurred myself. I truly relished the opportunity given in working with

them. Last but not least, my appreciation to Dr. Rushdan Ibrahim and Mohd. Jani Saad

from FRIM which supplied raw material, kenaf fiber. Subsequently to Mohd Yuhazri

Yaakob, Mohd Azhar Abu Shah, Nazri Mokte and all technicians involved to complete

this project. Finally, my sincere appreciation is dedicated to my parents and family and

as well as the friends for their priceless assistance and patronage throughout the process

of data gathering.

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TABLE OF CONTENTS

Abstract…………………………………………..…………………….…..…..…………i

Abstrak……………………………………………………………….….……..…..……iii

Dedication………………………………………………………….…..….…...………...v

Acknowledgement…………………………………………..……….………...………..vi

Table of Contents…………………………………………..…………………..…..…...vii

List of Figures………………………………………..…………………..……….…....xiii

List of Tables………………………………...………………………….……….….…xvii

List of Abbreviations, Symbols, Specialized Nomenclature……………....…....……xviii

1. INTRODUCTION……………………………………………………………….1

1.1 Introduction to Kenaf…………………………………………………...……….1

1.2 Statement of the Purpose……………………………………...…………………4

1.3 Hypotheses……………………………………………………...……………….5

1.4 Problem Statements……………………………………………………...………5

1.5 Objectives………………………………………………………………………..6

1.6 Scope of Study…………………………………………………………...……...7

2. LITERATURE REVIEW…………………………………………..……........8 2.1 Kenaf …………………..……………………………………………………….8

2.1.1 Plant Component Partitioning and Composition………………..……….8

2.1.1.1 Whole Stalk ……………………………………….……………..9

2.1.1.2 Bast Fiber………………….……………...………………….....10

2.1.1.3 Core Fiber……………………………………….………………11

2.1.2 Uses of Kenaf………………………………………………..………….12

2.1.2.1 Traditional Use of Kenaf………………………………..………12

2.1.2.2 Value Added Produces from Kenaf……………………………..13

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2.1.3 General Properties of Kenaf Fibers………………………….………….15

2.1.4 Separation of Kenaf Fiber………………..……………………………..17

2.1.4.1 Mechanical Separation Method………………………………….17

2.1.4.2 Water Retting Method……………………...……………………19

2.2 Composite……………………………………………………………………….20

2.2.1 Introduction …………………………………..….………………….….20

2.2.2 Matrix ……………………………………………………….………….21

2.2.2.1 Types of Matrix Resin…………………….…………..….….….21

2.2.2.2 Matrix Characteristics………………………….……………….21

2.2.3 Reinforcement……………………………….………………………….22

2.2.3.1 Types of Fiber Reinforcement…………………..………………22

2.2.4 Manufacturing Techniques……………………………………….……..22

2.2.5 Characteristics Influence the Properties of Composites……….………..23

2.2.6 Thermoset Polyester Resin……………………………………………...25

2.2.6.1 Introduction……………………………………………………..25

2.2.6.2 Physical Form…………………………………….……………..25

2.3.2.5 Characteristics…………………………………………………..25

2.2.6.4 Catalyst………………………………………….………..……..28

2.3 Mechanical Testing……………………………….……………………………30

2.3.1 Tensile Test…………………………………..…………….……………30

2.3.1.1 Definition and Purposes………………………...………………30

2.3.1.2 Specimen Shape……………………………………..………..…30

2.3.1.3 UTM Machine…………………………………………………..30

2.3.1.4 Grip and Face Selection…………………….……….…………..30

2.3.1.5 Specimen Alignment…………………….…………….………..31

2.3.1.6 Typical Configurations…………………….……………………31

2.3.2 Flexural Test…………………………………………………………….32

2.3.2.1 Definition and Purposes……………………………………..….32

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2.3.2.2 Specimen Shape…………………………………………………32

2.3.2.3 UTM Machine…………………………………………………..33

2.3.2.4 Typical Configuration…………………………………………..33

2.3.2.5 Three Point Flexural Test……………………………………….35

2.3.2.6 Testing calculation……………………………………..…….….36

2.3.3 Charpy and Izod Pendulum Impact Test………………………………..37

2.3.3.1 Definition and Purpose……………………………………...…..37

2.3.3.2 Specimen Shape……………………………………………..…..38

2.3.3.3 Impact Machine…………………………………………….…...39

2.4 Physical Testing………………………………………………………………...42

2.4.1 Water Absorption Test……………………………………………….…42

2.4.1.1 Definition and Purpose……………………………….…………42

2.4.1.2 Specimen Shape………………………………………….……..42

2.4.1.3 Tools and Equipment…………………………………………...42

2.5 Microstructure Observation………………………………………………...…..43

2.5.1 Definition and Purpose………………………………………………….43

2.5.2 Scanning Electron Machine (SEM)…………………………………..…43

2.5.3 Basic Operating ………………………………………………………...43

2.6 Previous Research on Natural Fiber Composite………………………………..45

2.6.1 High Fiber-Low Matrix Composites: Kenaf Fiber-Polypropylene…......45

2.6.2 Physical and Mechanical Properties of Composite Panels Made. From

Kenaf Plant Fibers and Plastics…………………………………………..46

2.6.3 Kenaf Fiber Reinforced Composite Athletic Wheelchair……………..…47

2.6.4 The Study on the Mechanical Properties of Natural Fiber Composite ...49

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3. METHODOLOGY…………………………………………..……………..….50

3.1 Introduction………………………………………………..……………………50

3.2 Process Sequence…………………………………………………….…………51

3.3 Kenaf Fiber Preparations……………………………………………………….53

3.3.1 Separation of Fibers………………………………………………….…55

3.3.2 Fiber Drying Process……………………………………………..…….56

3.4 Mould Fabrication………………………………………………………………57

3.4.1 Mould Designing………………………………………………………..57

3.4.2 Selection of Mould Material…………………………………...………..57

3.4.3 Mould Fabrication………………………………………………………61

3.5 Composite Fabrication…………………………………………………………..61

3.5.1 Composite Formulation…………………………………………………61

3.5.2 Preparation of Polyester and Hardener………………………………….62

3.5.3 Formulation/Composition of resin/filler………………………………...62

3.5.4 Fabrication Process……………………………………….……………..63

3.5.4.1 Casting with Liquid Resin……………………….……………63

3.5.4.2 Cutting of Composite…………………………….…….……..68

3.5.4.3 Notching Process………………………………….………..…69

3.6 Testing and Analysis………………………………………….…………….…..71

3.6.1 Mechanical Testing……………………………………...…….………..71

3.6.1.1 Tensile Tests………………………………………..……………..71

3.6.1.2 Flexural Tests………………………………….…….…………....72

3.6.1.3 Impact Tests……………………………………….…………..….72

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3.7 Physical Testing…………………………….………………..…………………73

3.7.1 Water Absorption Test…………………….……………………………73

3.8 Surface Topography of Bast and Core Fibers…………………………….…….74

4. RESULTS……………………………………………………….………76

4.1 Number of Specimens…………………………..................................………...76

4.2 Final Specimens…………………...……………………………………………78

4.3 Overall Specimens………………………………………………………….…..78

4.4 Kenaf Bast Fiber Reinforced Composite for Tensile Specimens………………79

4.5 Kenaf Core Fiber Reinforced Composite for Tensile Specimens………...……80

4.6 Surface Topography…………………….………………………….…..………81

4.6.1 Observation of Fiber Diameter……………………………….………....81

4.6.2 Observation of Fiber Surface………………………………….………...83

4.6.3 Matrix-Fiber Interfacial Bonding Observation………………………….84

5. DISCUSSION……………………………………………………………………86 5.1 Characteristic Influence the Composite Properties………………………….…86

5.1.1 Large Fiber Particle………………….………………….………………86

5.1.2 Dispersion of the Fiber………………………….………………………87

5.1.3 Influence of Fiber Length……………………….………………………87

5.1.4 Influence of Fiber Orientation…………………….…………………….89

5.1.5 Influence of Fiber Phase……………………….………………….…….89

5.1.6 Influence of Matrix Phase………………………….…………………...90

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5.2 Challenges during Preparation of the Specimen …………...………………….91

5.3 Data Analysis……………………………………………………………………93

5.3.1 Mechanical Test…………………………………………………………93

5.3.1.1 Tensile Test………………………………………………………….93

5.3.1.2 Flexural Test…………………………………………………………99

5.3.1.3 Impact Test…………………………………………………………102

5.3.2 Physical Test…………………………………………………….…….103

5.3.2.1 Water Absorption Test……………………………………………..103

5.3.2.1.1 Sorption Behavior…………………………………….…….….104

5.3.2.1.2 Effect of Moisture Absorption on Mechanical Properties…...107

5.3.2.1.2.1 Tensile properties………………………………………...108

5.3.2.1.2.2 Flexural properties………………………………………..109

5.3.2.1.2.3 Impact Properties…………………………………………111

6. CONCLUSION ...…………………………………………….……………….113 6.1 Conclusion………………...………………………………….……………….113

6.2 Recommendations…………………………………………………………….115

7. REFERENCES………..…………………………………………………..….116

8. APPENDICES

A The detail list of property values for a range of thermoset polyester compounds

B Machines involved in the mould fabrication

C Formulation of composite fabrication

D Calculation of tensile test

E Calculation of flexural test

F Calculation of impact test

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LIST OF FIGURE 1.1 Kenaf Plantatition...……………… ...………….……… ...………………..…….2

1.2 Kenaf stalks...……………… ...………………… ...………………………..……3

2.1 Kenaf stalks with bast and core material...….…………… ...……………..……..9

2.2 Kenaf bast fiber strands...………………… ...………….…… ...………….…...11

2.3 Core fiber material...………………… ...………….…… ...……………….…...12

2.4 Kenaf Fiber Images...………………… ...……….……… ...……………….….16

2.5 Schematic of Stick Machine Trash Master...……….……… ...……………..….18

2.6 Water retting process...………………… ...……….……… ...……………..…..19

2.7 Formation of a composite material using fibers and resin...………………...….20

2.8 Continuous fiber composites and short fiber composites...…………….…..…...20

2.9 Crosslinking of thermoset molecules during curing...……………………...…...22

2.10 Schematic representations of various geometrical and spatial characteristics of.

particles...…………………………………………………… ……………….…24

2.11 Reaction A(1) ...………………… ...………………… ...…………………...…25

2.12 Reaction A (2) ...……..………… ...………………… ...………………………26

2.13 Reaction B...……………… ...………………… ...……….………………..…..26

2.14 MEKP catalyst ratio...……………… ...………………… ...………………..…29

2.15 Tensile configurations...……………… ...………………… ...………………...31

2.16 Location of tensile and compressive forces during three-point bending...……..33

2.17 Crack propagation and failure during three-point bending...…………………...34

2.18 Three point bending...……………… ...………………… ...………………...…36

2.19 Schematic striker movement of impact machine...……………………………..38

2.20 Impact machine...……………… ...………………… ...…………………..…...39

2.21 Charpy and Izod specimens’ positioning...……………… ...………………..…40

2.22 Charpy impact strike-specimen configuration...……………………….……..…41

2.23 SEM component...…………… ...………………… ...………...…………...…..43

2.24 SEM operating...………………… ..………………… ...………………………44

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3.1 Process sequence...………………...………………… ...…………………...….51

3.2 Process flow chart...………………… ...………………… ...…………………..52

3.3 Moist kenaf fiber from kenaf stems...……………… ...……………………...…54

3.4 Dry kenaf fiber...………………… .………………… ...………………………54

3.5 Moist kenaf fiber after defibering process...……………… ...……………...…..55

3.6 The figure shows the separated dry kenaf...……………… ...……………….....56

3.7 Mould positioning...………………… ...……………… ...………………….....58

3.8 The failure of acrylic mould...………………… ...……………… ...…………..59

3.9 Mild steel mould...………………… ...……………… ...……………………....59

3.10 Mold with frame set...………………… ...……………… ...………………...…60

3.11 Tensile mould...………………… .………………… ...………………….…….60

3.12 Hand proportioning, mixing, pouring and curing with two components...……..63

liquid reactive polyester resin system

3.13 Schematic of the composite consolidation...……………… ...…..……….…….64

3.14 Mould coated by plastic...……………… ...…………………………..…..…….64

3.15 Gelcoat...………………… ...…………………...………………… …….……..65

3.16 Polyester Resin...………………...………………… ...……….………………..65

3.17 Mixing the liquid composite...……………… ...………………….…………….65

3.18 Liquid composites are poured into the mould cavity...……………… ….…..…66

3.19 Mechanical cold press machine 100 Ton………………… ...……………….…67

3.20 Unfilled composite, moisture kenaf bast fiber and 20% kenaf bast fiber……....67

3.21 Cutting process...……………… ...………………… ...……………………..…68

3.22 Notching process...……………… ...………………… ...……………………...70

3.33 Notched impact’s specimen notch angle and depth of notch…………………...70

3.34 Water absorption test...……………… ...………………… ...……………….....73

3.35 The fibers are placed on the stage...……………… ...………………………….75

4.1 Figure shows for all specimens...……………… ...…………………….…..…..78

4.2 Kenaf bast fiber reinforce polyester composite..………………… ...…….…….79

4.3 Kenaf core reinforce polyester composite...……………… ...………….…...….80

4.4 Micrograph of kenaf bast fiber...……………… ...……………………………..81

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4.5 Micrograph of kenaf core fiber...……………… ...………………………….….82

4.6 Micrograph of kenaf bast fiber with 2000 x magnification...…………………...83

4.7 Micrograph of kenaf core fiber with 335 x magnification...…………….…...…83

4.8 SEM fracture surface of kenaf bast fiber reinforce polyester composite…….....84

4.9 SEM image of fracture surface of kenaf core fiber with polyester…………..…85

5.1 The non uniform dispersion composite…………………...………………….....87

5.2 Matrix-fiber deformation pattern..………………… ...…………………………88

5.3 The failure of the composite pallet specimens...……………… ...…………..…91

5.4 Failure of unfilled composites...……………… ...…………………………...…92

5.5 Graph for tensile Strength vs. Volume Fiber Fraction for Kenaf Bast and.....…93

Core Fiber Reinforced Composites.

5.6 Histogram graph for tensile Strength vs. Volume Fiber Fraction for Kenaf.…..95

Bast and Core Fiber Reinforced Composites.

5.7 SEM micrograph for kenaf core fiber.. ...…………… ...……………..….…….96

5.8 Graph for Stress vs. Strain for 20% fiber volume fraction of kenaf bast……….97

fiber reinforced composites shows the highest value of maximum

force and modulus young.

5.9 Graph for Flexural Strength vs. Fiber Volume Fraction for Kenaf Bast and.......99

Core Fiber Reinforced Composites

5.10 Histogram graph for Flexural Strength vs. Fiber Volume Fraction for...…...…100

Kenaf Bast and Core Fiber Reinforced Composites.

5.11 Graph for Impact Strength vs. Fiber Volume Fraction for Kenaf Bast and…...102

Core Fiber Reinforced Composites.

5.12 Histogram graph for Impact Strength vs. Fiber Volume Fraction for Kenaf….103

Bast and Core Fiber Reinforced Composites

5.13 Graph for Weigh Gain vs. Fiber Volume Fraction for Kenaf Bast and…….....106

Core Fiber Reinforced Composites

5.14 Histogram graph for Weigh Gain vs. Fiber Volume Fraction for Kenaf……...107

Bast and Core Fiber Reinforced Composites

5.15 Graph for tensile strength vs. fiber volume fraction for kenaf bast fiber……..108

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reinforced composite

5.16 Flexural strength vs. fiber volume fraction for kenaf core and bast fiber…..…110

reinforced composite

5.17 Histogram graph for Impact Strength vs. Fiber Volume Fraction for…………111

Kenaf Bast Fiber Reinforced Composites for notched impact specimen.

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LIST OF TABLE

2.1 The characteristics of liquid resins for non electrical applications………..……27

2.2 MEKP Catalyst ratio............................................................................................28

4.1 Number of specimens had been produced………………………………...…….76

5.1 Data of Tensile Testing………………………………………….………..…….93

5.2 Table for data of graph Stress vs. Strain………………………………..…….…97

5.3 Data of Flexural Testing………………………………………………..…….…99

5.4 Data of Notched Charpy Impact Testing………………………...……..……...102

5.5 Data of Water Absorption Testing…………………………………...………..105

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LIST OF ABBREVIATIONS, SYMBOLS, SPECIALIZED

NOMENCLATURE

in - inches

kg - kilograms

m - Meter

Max - maximum

Min - minimum

s - Second

V - velocity 0C - degrees Celsius 0F - degrees Fahrenheit

% - Percent

+/- - plus or minus

SEM - Scanning Electron Microscope

PP - Polypropylene

FRIM - Forest Research Institute of Malaysia

PMCs - Polymer–Matrix Composites

BMW - Bavaria Motor Works

SMC - Sheet Molding Compound

BMC - High Bulk Compound

TMC - Thick Molding Compound

MEKP - Methyl Ethyl Ketone Peroxide

oz - ounces

cc - cubic centimeter

qt - quantity

MOR - modulus of rupture

G - Giga

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M - Mega

Pa - Pascal

RHP - Rice Husk Powder

HDPE - High Density Polyethylene

KFRUPE - Kenaf Fiber Reinforced Unsaturated Polyester

ASTM - American Standard Testing Material

UP - Unsaturated Polyester

MARDI - Malaysian Agricultural Research and Development Institute

ΔM(t) - % Water absorption

Mo - Dry weight

Mt - Wet weight

hp - Horse power

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CHAPTER 1

INTRODUCTION

1.1 Introduction to Kenaf

Kenaf or its scientific name Hibiscus cannabinus L is a warm season annual fiber

crop closely related to cotton and jute. Historically, kenaf has been used as a cordage

crop to produce twine, rope and sackcloth. Nowadays, there are various new applications

for kenaf including paper products, building materials, absorbents and animal feeds. In

Malaysia, realizing the diverse possibilities of commercially exploitable derived

products from kenaf, the National Kenaf Research and Development Program has been

formed in an effort to develop kenaf as a possible new industrial crop for Malaysia. The

government has allocated RM12 million for research and further development of the

kenaf-based industry under the 9th Malaysia Plan (2006–2010) in recognition of kenaf

as a commercially viable crop.

Kenaf has a single, straight and branchless stalk. Kenaf stalk is made up of an

inner woody core and an outer fibrous bark surrounding the core. The fiber derived from

the outer fibrous bark is also known as bast fiber. Kenaf bast fiber has superior flexural

strength combined with its excellent tensile strength that makes it the material of choice

for a wide range of extruded, molded and non-woven products. Kenaf fiber could be

utilized as reinforcement material for polymeric composites as an alternative to glass

fiber.