The Impact And Flexural Study Of The Polymeric Biocomposite.

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THE IMPACT AND FLEXURAL STUDY OF THE

POLYMERIC BIOCOMPOSITE

KUWN YEW CHING

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UTeM Library (Pind.1/2007)

UNIVERSITI TEKNIKAL MALAYSIA MELAKA

BORANG PENGESAHAN STATUS TESIS*

Disahkan ol eh:

(TANDATANGAN PENULIS) Alamat Tet ap:

395, MK 20, KUBANG SEMANG, 14400 BUKIT MERTAJAM

PULAU PINANG

Tarikh: 25 MARCH 2008

(TANDATANGAN PENYELIA) Cop Rasmi:

Tarikh: _______________________

* Tesis dimaksudkan sebagai t esis bagi Ij azah Dokt or Falsaf ah dan Sarj ana secara penyelidikan, at au

(Mengandungi maklumat TERHAD yang t elah dit ent ukan oleh organisasi/ badan di mana penyelidikan dij alankan) TIDAK TERHAD

TERHAD

(Mengandungi maklumat yang berdarj ah keselamat an at au kepent ingan Mal aysia yang t ermakt ub di dalam AKTA RAHSIA RASMI 1972)

SULIT

JUDUL: THE IMPACT AND FLEXURAL STUDY OF THE POLYMERIC BIOCOMPOSITE

SESI PENGAJIAN : 2007-2008

Saya KUWN YEW CHING_____________________________________________

mengaku membenarkan t esis (PSM/ Sarj ana/ Dokt or Falsaf ah) ini disimpan di Perpust akaan Universit i Teknikal Malaysia Melaka (UTeM) dengan syarat -syarat kegunaan sepert i berikut :

1. Tesis adalah hak milik Universit i Teknikal Malaysia Melaka .

2. Perpust akaan Universit i Teknikal Malaysia Melaka dibenarkan membuat salinan unt uk t uj uan pengaj ian sahaj a.

3. Perpust akaan dibenarkan membuat salinan t esis ini sebagai bahan pert ukaran ant ara inst it usi pengaj ian t inggi.

4. **Sila t andakan (√)

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UNIVERSITI TEKNIKAL MALAYSIA MELAKA Karung Berkunci 1200, Ayer Keroh, 75450 Melaka

Tel : 06-233 2421, Faks : 06 233 2414 Email : fkp@kutkm.edu.my

FAKULTI KEJURUTERAAN PEMBUATAN

Rujukan Kami (Our Ref) : 25 Mac 2008

Rujukan Tuan (Your Ref):

Pustakawan

Perpustakawan Universiti Teknikal Malaysia Melaka UTeM, No 1, Jalan TU 43,

Taman Tasik Utama, Hang Tuah Jaya, Ayer Keroh, 75450, Melaka

Saudara,

PENGKELASAN TESIS SEBAGAI SULIT/TERHAD

- TESIS SARJANA MUDA KEJURUTERAAN PEMBUATAN (FAKULTI KEJURUTERAAN PEMBUATAN): KUWN YEW CHING

TAJUK: THE IMPACT AND FLEXURAL STUDY OF THE POLYMERIC BIOCOMPOSITE

Sukacita dimaklumkan bahawa tesis yang tersebut di atas bertajuk _“THE IMPACT AND FLEXURAL STUDY OF THE POLYMERIC BIOCOMPOSITE_”mohon dikelaskan sebagai terhad untuk tempoh lima (5) tahun dari tarikh surat ini memandangkan ia mempunyai nilai dan potensi untuk dikomersialkan di masa hadapan.

Sekian dimaklumkan. Terima kasih.

“BERKHIDMAT UNTUK NEGARA KERANA ALLAH”

Yang benar,

……….. Prof Dr Md Dan Md Palil

Pensyarah,

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DECLARATION

I hereby, declare this thesis entitled “The Impact and Flexural Study of The Polymeric Biocomposite”

is the result of my own research except as cited in the references.

Signature : __________________ Author’s Name : KUWN YEW CHING

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APPROVAL

This report is submitted to the Faculty of Manufacturing Engineering of UTeM as a partial fulfillment of the requirement for the degree of Bachelor of Manufacturing Engineering (Engineering Materials). The members of the supervisory committee are as

follow:

PROF. DR MD DAN MD PALIL

……….. (Main Supervisor) Official Stamp & Date

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ABSTRACT

The polymeric bio-composite material is a material constituent a polymeric matrix (resin) and a reinforcement of natural fibers which are usually derived from

plants or cellulose.The objectives for this study are to study on the impact properties

and flexural properties of the polymeric composite. The bio-material material that used to fabricate the specimens was based on commercially available unsaturated polyester. kenaf fibre from kenaf plant. Besides that, the fibre that used will treated with alkali treatment with various concentrations such as 3%, 6% and 9% NaOH but with same soaking times that is 12 hours. For the manufacturing process, the kenaf / polyester is prepared by using Resin Infusion Process (RIP) with several equipments and tools. 5 pieces specimens of each testing were tested with flexural and impact machine. Following by that, the morphology of the surface fracture is investigated using Scanning Electron Microscope (SEM). Based on this finding, the flexural properties was increasing gradually as the chemical concentration treatment in composite increased. It is observed that the flexural strength increased from 0.0251 GPa to 0.0934 GPa and flexural modulus increased from 2.298 GPa to 7.137 GPa respectively for untreatment fibre to 9% fibre. Lastly for the impact properties, the

impact strength and impact modulus are indicated a rise from 3.57 kJ/m2 to 15.77

kJ/m2 as the fibre content increased from untreated to 6% concentration but

decreased to 2.47 kJ/m2 when used 9% concentration treatment on kenaf fibre. This

is because this natural fibre is considered oriented short fibre composites with strong cellulossic microfibres of different lengths.

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ABSTRAK

Bahan bio-komposit merupakan bahan yang terkandung polimerik matrik (resin) dan gentian semula jadi yang biasanya terdiri daripada tumbuhan dan cellulose. Projek ini bertujuan untuk mengkaji ujian hentaman dan kelenturan bagi polimerik komposik. Bahan matriks digunakan dalam membuat spesimen adalah berdasarkan kepada polyester tidak tepu yang didapati secara komersil dan gentian kenaf yang dijumpai daripada pokok kenaf. Selain itu, gentian kenaf yang dijalankan dengan proses rawatan alkali dengan kepekatan berbeza seperti 3%, 6% dan 9% tetapi dengan rendaman masa yang sama iaitu 12 jam. Bagi proses pembuatannya, komposit kenaf dan polyester adalah disediakan dengan menggunakan Proses Seduhan Resin. 5 keping specimen bagi setiap satu kajian diuji dengan ujian hentaman dan kelenturannya. Selepas itu, specimen yang diuji dengan ujian ujian hentaman dan dianalisis dengan Mikroskop Pengimbas Elektron. Berdasarkan kajian, sifat kelenturan akan semakain bertamabah kerana kepekatan kimia bertambah. Hal ini dapat dilihat bagi kekuatan kelenturan bertambah dari 0.0251 GPa ke 0.0934 GPa manakala kelenturan modulus pula bertamabah dari 2.298 GPa ke 7.137 GPa masing-masing bagi gentian tanpa rawatan kimia ke 9% gentian. Bagi sifat hentaman, kekuatan hentaman dan

hentaman modulus menunjukkan peningkatan dari 3.57 kJ/m2 ke 15.77 kJ/m2

apabila kandungan gentian bertambah dari tanpa rawatan ke 6% kepekatan tetapi

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DEDICATION

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ACKNOWLEDGEMENTS

First, I would like to express a thousand thanks to Prof Dr Md Dan Md Palil. He as my Project Sarjana Muda II supervisor had provided not only his private times to help me corrected my draft report but also provided his knowledge to solve the problem that I confronted. Besides that, I also taken this opportunity to express grateful for her kindness to Miss Zaleha Bt Mustafa due to her help for guide me during doing Project Sarjana Muda I although she already went for further study in United Kingdom.

Secondly is I want express thankful to my fellow friend, Mr. Cheng Yuan We and master students whom En. Khiralsalleh Bin Abdul Aziz and En. Phongsakorn A/L Prak Tom during doing the PSM. I would like specially thank for your helpful hand during conducted experiment. Without your help, I sure cannot finish my work on the date. I feel thankful and I would like to meet with you people again if have chance. Thanks and wishing you all the best in future.

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TABLE OF CONTENTS

Abstract i

Abstrak ii

Dedication iii

Acknowledgements iv

Table of Contents v

List of Figures ix

List of Tables xi

Nomenclature xii

1.0 INTRODUCTION 1

1.1 Introduction 2

1.2 Problem Statement 2

1.3 Objectives 2

1.4 Scope of Research 3

2.0 LITERATURE REVIEW

2.1 Composite 4

2.1.1 Thermoplastics 5

2.1.2 Thermoset 5

2.1.3 Elastomers 5

2.2 Biocomposite 6

2.2.1 The Reinforcement 6

2.2.2 The matrix 9

2.2.2.1Polyester 10

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2.2.2.3Epoxy 11

2.2.3 Fibers Types 12

2.3 Types of Composites 13

2.3.1 Metal Matrix Composite (MMCs) 13

2.3.2 Ceramic Matrix Composites (CMCs) 14

2.3.3 Polymer Matrix Composites (PMC) 15

2.4 Natural Fibres Reinforcements in Composites 17

2.4.1 Kenaf 19

2.4.1.1History and Uses 19

2.4.1.2Taxonomy 20

2.4.1.3Fibre Retting and Extraction Techniques 21

2.5 Synthetic Fibre 22

2.6 Processing 23

2.6.1 Hand Lay-up 23

2.6.2 Vacuum Infusion 24

2.7 Composite Properties 25

2.7.1 Flexural Tests 25

2.7.2 Impact Tests 33

3.0 METHODOLOGIES MATERIAL

3.1 Research Flowchart 38

3.2 Raw Materials Preparation 39

3.2.1 Fibre 39

3.2.2 Fibre Treatment 39

3.2.3 Polyester 40

3.2.4 Process Sequence of PS-kenaf Composite 41

3.3 Materials and Equipments 42

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3.5 Testing Methods 47

3.5.1 Flexural Testing 47

3.5.1.1 Sampling for Flexural Analysis 48

3.5.2 Impact Testing 48

3.5.2.1 Sampling Analysis for Impact 49

3.5.3 Scanning Electron Microscopy (SEM) 50

4.0 RESULTS AND DISCUSSION

4.1 Introduction 53

4.2 Flexural Properties 53

4.2.1 Flexural Modulus 53

4.2.2 Flexural Strength 55

4.2.3 Comparison between Flexural Modulus and

Flexural Strength 56

4.2.4 Analysis Graph of the Strongest and Weakness for

Flexural Test 57

4.3 Impact Properties 59

4.3.1 Impact Modulus 59

4.3.2 Impact Strength 61

4.3.3 Comparison between Impact Modulus and

Impact Strength 63

4.4 Morphological Analysis 64

4.4.1 Kenaf fibre 64

4.4.2 Kenaf/Polyester Composites 65

5.0 CONCLUSION AND RECOMMENDATION

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5.2 Recommendation 70

REFERENCES 72

APPENDICES

A Result for Flexural Test (Untreated) B Result for Flexural Test (T1)

C Result for Flexural Test (T2) D Result for Flexural Test (T3) E Materials and Equipments F Gantt chart PSM I

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LIST OF FIGURES

2.1 The types of matrix 8

2.2 Properties of different natural reinforcing fibres 17

2.3 Diagram for Reinforcing Natural Fibres 18

2.4 Allowable Range of Loading Nose and Support Radii in ASTM

D790

2.5 Flexural strength comparison of compression molded composites 29

2.6 Relationship between flexural modulus and the number of kenaf 30

2.7 Flexural strength of fibre reinforced polypropylene composites 30

2.8 Flexural modulus of TLK–polyester A, B, C and D composites 32

2.9 Flexural strength of TLK fibre–polyester A, B, C and D

composites

2.10 Pendulum Impact Test – Notched Izod Impact Test 33

2.11 Relation of Vise, Specimen and Striking Edge to Each Other for

Izod Test Method A in ASTM D256

2.12 The dimension of the Izod test specimen (ASTM D 256) 35

2.13 Charpy impact strength of fibre reinforced polypropylene composites

2.14 Notched and unnotched Izod impact strengths of the composites at different filler loadings

3.1 Flowchart of the research 38

3.2 Kenaf fibre 39

3.3 The various Kenaf fibre treatment 40

3.4 Process sequence that applied in the fabrication of Unsaturated

Polyester-kenaf composites

3.5 General setup of resin infusion process 46

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3.7 Sample of Flexural Testing 48

3.8 Impact Testing Machine 49

3.9 Sample of Impact Testing 49

3.10 Scanning Electron Microscopy (SEM) 51

3.11 The fracture area for flexural testing 51

3.12 The fracture part for impact testing 52

4.1 Comparison of Flexural Modulus for Kenaf/Polyester with

different Concentration 53

4.2 Comparison of Flexural Strength for Kenaf/Polyester with

different Concentration 55

4.3 Figure 4.3: Graph for Flexural Modulus and Flexural Strength

with different concentration treatment 56

4.4 Graph of the strongest for flexural test (Sample T3, 9% NaOH

Treatment) 57

4.5 Graph of the weakness for flexural test (Sample UT, without

NaOH Treatment) 58

4.6 Comparison of impact Modulus for Kenaf/Polyester with

different concentration treatment 59

4.7 Comparison of impact strength for Kenaf/Polyester with different

concentration treatment 61

4.8 Graph for Impact Modulus and Impact Strength with different

concentration treatment 63

4.9 Kenaf fibre for untreated sample 64

4.10 Kenaf fibre for T1 sample (3% NaOH) 64

4.11 Kenaf fibre for T2 sample (6% NaOH) 64

4.12 Kenaf fibre for T3 sample (9% NaOH) 64

4.13 Micrograph of Untreated Kenaf/Polyester composite 65

4.14 Micrograph of treated Kenaf/Polyester composite (3% NaOH) 66

4.15 Micrograph of treated Kenaf/Polyester composite (6% NaOH) 66

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LIST OF TABLES

2.1 Comparison between natural and glass fibres 19

2.2 Scientific classification 20

2.3 The comparison properties among the synthetic fibres 22

2.4 Flexures test parameter 28

2.5 Dimensions of Izod-Type Test Specimen 35

3.1 Alkali Treatment Process 40

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LIST OF ABBREVIATIONS, SYMBOLS, SPECIALIZED

NOMENCLATURE

% - percentage

°F - Degree of Fahrenheit

ASTM - American Society for Testing and Materials

b - Width of beam tested

CMC - Ceramic Matrix Composites

d - Depth of beam tested deflection curve

EB - modulus of elasticity in bending

FRP - Fibre reinforcement Polymers

HDPE - High Density Polypropylene

in. - inch

J - in unit joule

kN - kilo Newton

kJ/m2 - kilo joule per millimeter square

L - Support span

lbf /in - pound force per in

lbf - Pounds of Force

LDPE - Low Density Polypropylene

NaOH - Sodium Hydroxide

M - Slope of the tangent to the initial straight line portion

of the load

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mm - millimeter

MMCs - Metal Matrix Composites

MPa - Mega Pascal

N - unit SI Newton

N/mm - Newton per millimeter

NF - Natural Fibre

ºC - degree Celsius

P - load at a given point on the load deflection curve

Pa - in unit Pascal

PMCs - Polymer Matrix Composites

psi - pound per square inch

R - Rate of cross head motion

RIP - Resin Infusion Process

RTM - Resin Transfer Moulding

SEM - Scanning Electron Microscopy

SI - International System of Units

TLK - Treated Long Kenaf

UTM - Universal Tensile Machine

UT - Untreated fibre

% wt - percentage weight

Z - Rate of straining of the outer fibre

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CHAPTER 1

INTRODUCTION

1.1 Introduction

Composite materials in research often require certain modifications in order to improve their properties. Nowadays, composites offer greatly reduced maintenance compared with steel and concrete and therefore offer whole life cost benefits. However, first cost is the major and often the only parameter used by clients in decision making despite much talk about whole life costing.

Composite materials are engineered materials formed through the physical combination of two or more materials; these are the fibres/fillers and the matrix; together with any additives which may be required to give the composite specific physical properties. The combination of the materials will differ in form or composition at the macro scale, for the purpose of improving or enhancing properties. (Wikipedia 2006). There are two categories of constituent materials: matrix and reinforcement.

The research work will focus on study of the mechanical properties of the composite focusing on impact and flexural properties in the laboratory scale. There are several processing stage in sampling fabrication by using vacuum infusion technique. This will followed by testing stage in order to investigate the mechanical properties and

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others. This analysis data of the finding after that will compared with existing materials used in order to verify that this new composite has the potential to be use as the substitution material in structural application.

1.2 Problem Statement

Metals are used as major application in many fields in long time ago. Even though metals are known for their outstanding mechanical properties, the costs of their raw materials somehow outweight the inherent benefits. But today, the selections of materials in the market are shifted to the lightweight composite. This scenario gives an opportunity to explore on producing a lightweight composite since the cost for producing in Malaysia is inexpensive compared with metals yet at the same time maintaining the outstanding mechanical properties. In this research, the main focus is to use kenaf as the substitute materials for the steel, as reinforcement in polymer matrix for polyester in order to produce a high impact composite but lightweight. Before that, the usage of kenaf mainly for furniture likes its counterpart the wood and bamboo. Now, this has force the researcher to find other substitution materials and kenaf is believed has the potential to replace this role as it functions as a good reinforce in suitable matrix material.

1.3 Objectives

The specific objectives of this research were to:

i. To investigate the impact properties of various chemical concentration treatment for kenaf/Polyester composite.

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ii. To analyze the flexural properties of various chemical concentration treatment for kenaf/Polyester composite

iii. To study the fibre matrix interaction by scanning electron microscopy (SEM)

1.4 Scopes of Research Methodology

The scopes of research were:

(i.) Preparation of kenaf and polyester (ii.) Characterization of kenaf and polyester (iii.) Treatment of fibre prepared

(iv.) Resin Infusion Process

(v.) Testing to find out mechanical properties ¾ Flexural Test (ASTM D790) ¾ Impact Test (ASTM D256

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CHAPTER 2

LITERATURE REVIEW

2.1 Composite

Since there are so many different plastics with different properties and structures, so the subject of polymeric materials may seen overwhelming to the average material user. Plastics can be divided into two types relating to their elevated temperature which are thermoplastic and thermoset. (Budinski et al., 1999)

Composites have many engineering advantages over synthetic polymers and copolymers. Some of these advantages are :

i. Reinforcement of the resin resulting in increased tensile strength, flexural

strength, compression strength, impact strength, rigidity and combination of these properties.

ii. Increased size stability.

iii. Improved fire retardancy.

iv. Corrosion protection.

v. Improved electrical properties; reduction of dielectric constant.

vi. Coloring.

vii. Improved processibility; controlled viscosities, good mixing, controlled

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2.1.1 Thermoplastics

Thermoplastic, is a material that is plastic or deformable, melts to a liquid when heated and freezes to a brittle, glassy state when cooled sufficiently. A thermoplastic material will flow at elevated temperatures (above the glass transition temperature or crystalline melting point), and the solidified polymer can be reheated as many times as desired and it will do the same thing. These include polyethylene, polypropylene, polystyrene and polyvinyl chloride. (Budinski et al., 1999)

2.1.2 Thermoset

Thermosetting plastics (thermosets) are polymer materials that cure, through the addition of energy, to a stronger form. Thermoset, once their shape has been made by casting or by plastic flow at elevated temperature, will not longer melt or flow on reheating. Principle thermosets are epoxies, polyesters and formaldehyde-based resins. When the molecular weight has increased to a point so that the melting point is higher than the surrounding ambient temperature, the material will forms into a solid material during the reaction. After it is cured, a thermoset material cannot be melted and re-shaped. They do not lend themselves to recycling like thermoplastics, which can be melted and re-molded. (Budinski et al., 1999)

2.1.3 Elastomers

This term of polymer is used to describe a polymer that has rubber like properties. The derivation of the term comes from elastic, the ability of a material to return to its original dimensions when unloaded, and mer, the term used in polymer chemistry to

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refer to a molecule. Since recovery in some polymers is not rapid, so not all elastomers can meet their definition of a rubber. A more usable definition of an elastomer is a polymeric material that has elongation rates greater than 100% and a significant amount of resilience and it refer to a material’s ability to recover from elastic deflections. It measured with the amount of energy lost in deflection. It means that a material with a good resilience when dropped from a height onto a rigid surface will rebound to almost its original height (Budinski et al., 1999).

2.2 Biocomposite

Biocomposites are composite materials comprising one or more phases derived from a biological origin. In terms of the reinforcement, this could include plant fibres such as cotton, flax, hemp and the like, or fibres from recycled wood or waste paper, or even by-products from food crops. Matrices may be polymers, ideally derived from renewable resources such as vegetable oils or starches. Alternatively, and more commonly at the present time, synthetic, fossil-derived polymers preponderate and may be either ‘virgin’ or recycled thermoplastics such as polyethylene, polypropylene, polystyrene and polyvinyl chloride, or virgin thermosets such as unsaturated polyesters, phenol formaldehyde, isocyanates and epoxies (Fowler et al., 2006).

2.2.1 The Reinforcement

Fibre reinforcement may be used in several different forms or arrangements, depending on the application and manufacturing route. They are categorised firstly in terms of length:

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CHAPTER 1

INTRODUCTION

1.1 Introduction

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1.2 Problem Statement

1.3 Objectives

The specific objectives of this research were to:

i. To investigate the impact properties of various chemical concentration treatment for kenaf/Polyester composite.

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ii. To analyze the flexural properties of various chemical concentration treatment for kenaf/Polyester composite

iii. To study the fibre matrix interaction by scanning electron microscopy (SEM)

1.4 Scopes of Research Methodology

The scopes of research were:

(i.) Preparation of kenaf and polyester (ii.) Characterization of kenaf and polyester (iii.) Treatment of fibre prepared

(iv.) Resin Infusion Process

(v.) Testing to find out mechanical properties

¾ Flexural Test (ASTM D790)

¾ Impact Test (ASTM D256

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CHAPTER 2

LITERATURE REVIEW

2.1 Composite

Composites have many engineering advantages over synthetic polymers and copolymers. Some of these advantages are :

i. Reinforcement of the resin resulting in increased tensile strength, flexural strength, compression strength, impact strength, rigidity and combination of these properties.

ii. Increased size stability. iii. Improved fire retardancy. iv. Corrosion protection.

v. Improved electrical properties; reduction of dielectric constant. vi. Coloring.

vii. Improved processibility; controlled viscosities, good mixing, controlled orientation of fibress.

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2.1.1 Thermoplastics

2.1.2 Thermoset

2.1.3 Elastomers

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2.2 Biocomposite

2.2.1 The Reinforcement

Fibre reinforcement may be used in several different forms or arrangements, depending on the application and manufacturing route. They are categorised firstly in terms of length:

The Impact And Flexural Study Of The Polymeric Biocomposite.