thanks to almighty allah

99 Pages·2015·3 MB·English

THANKS
TO

ALMIGHTY
ALLAH

i
PRROOCCEESSSSIINNGGAANNDD CHARACTERIZATIONOF WWASTE
DENIM FIBER REEIINNFFOORRCCEEDD POLYMER COOMMPPOOSSIITTEESS

MMOOBBAASSHHEERRAA SSAAIIMMAA HHAAQQUUE
SSTTUUDDEENNTT NNUUMMBBEERR 00412112006

DDEEPPAARRTTMMEENNTT OOFF MMAATTEERRIIAALLSS AANNDD MMEETTAALLLLUURRGGIICCAAL
ENGINEERING

BANGLADESH UNIVERSITY OF ENGINEEERRIINNGG AANNDD
TECHNOLOGY
DDHHAAKKAA,, BBAANNGGLLAADDEESSHH
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PROCESSINGAND CHARACTERIZATIONOF WASTE
DENIM FIBER REINFORCED POLYMER COMPOSITES

BY
MOBASHERA SAIMA HAQUE
STUDENT NUMBER 0412112006

THIS THESIS PAPER IS SUBMITTED TO THE DEPARTMENT OF
MATERIALS AND METALLURGICAL ENGINEERING
AS PARTIAL FULFILLMENT OF THE REQUIREMENTS
FOR
THE DEGREE OF MASTERS OF SCIENCE IN MATERIALS AND
METALLURGICAL ENGINEERING

DEPARTMENT OF MATERIALS AND METALLURGICAL
ENGINEERING

BANGLADESH UNIVERSITY OF ENGINEERING AND
TECHNOLOGY
DHAKA, BANGLADESH

SEPTEMBER2014
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CERTIFICATION

This is to certify that the work presented in this thesis paper is the outcome &
investigation carried out by the candidate under the supervision of Professor Dr. Ahmed
Sharif, Department of Materials & Metallurgical Engineering, Bangladesh
University of Engineering and Technology, Dhaka. It is also declared that this thesis
embodies own research work & is composed by the author, where appropriate
acknowledgement to the work of others have been made.

MOBASHERA SAIMA HAQUE

Signature of the Supervisor

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ACKNOWLEDGEMENT

The author expresses her deep and sincere gratitude to her supervisor and respected
mentor Professor Dr. Ahmed Sharif for his patience, motivation, enthusiasm and
guidance throughout the course of this thesis project, despite of his busy schedule. His
understanding, personal guidance, support has provided her with a good knowledge about
this thesis.

The author also conveys her heartiest thanks to Md. Harun-Or-Rashid for his never-
ending co-operation and help while performing tests and is grateful to the Department of
Glass and Ceramic Engineering (BUET) for the assistance with SEM.

Finally, she would like to thank Almighty Allah for everything.

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ABSTRACT

In this research, polymer matrix composites of denim fiber reinforcements with a view to
recycling the wastes from garments industries are studied. Polypropylene matrix based
composite structures were prepared by using waste denim fiber at different wt.% and for
different fiber orientations. The mechanical, thermal, chemical and morphological
properties of the composites were characterized.

The results indicated that the flexural strength and the flexure modulus of the composites
improved with increasing fiber percentage because even dispersion of fibers in the matrix
can be possible for higher percentage of fibers and the huge amount of fibers are
capable to withstand higher bending load. Better tensile properties were obtained at lower
fiber content. Agglomeration of fibers, increase in fiber–fiber interaction and the
increased void content all are responsible for the reduced tensile strength of the
composites containing higher fiber percentage. Lower values of hardness at higher fiber
fraction were obtained due to the presence of voids and porosity. The surface
morphology of the fracture surfaces of the tensile specimens, examined by a field
emission scanning electron microscope, revealed the poor interfacial bonding between
fiber and matrix and as well as the presence of micro voids and blowholes in the fracture
surface. The infrared spectra of pp-denim fiber composites were taken and the
characteristic peaks were studied. The lower thermal stability of the newly developed
composites was confirmed by thermo gravimetric analysis (TGA).

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List of Contents

Certification iv
Acknowledgement v
Abstract vi
List of contents vii

Chapter 1 1

Introduction 1

1.1 General Overview of Waste Fiber Reinforced Composite Materials 1
1.2 Rationale of Using Denim Fiber 2
1.3 Objective of The Work 3

Chapter 2 4

Literature review 4

2.1 Composite Materials 4
2.2 Classification of Composites 5
2.2.1 Composite Classification on the Basis of the Dispersed Phase 5
2.2.1.1 Particle-Reinforced Composites 6
2.2.1.2 Fiber-Reinforced Composites 7
2.2.1.2.1 Influence of Fiber Length 7
2.2.1.2.2 Influence of Fiber Orientation and Concentration 9
2.2.1.3 Structural Composite 10
2.2.1.3.1 Laminar Composites 10
2.2.1.3.2 Sandwich Panels 10
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2.2.2 Composite classification on the basis of matrices 11
2.2.2.1 Metal Matrix Composites (MMC) 12
2.2.2.2 Ceramic Matrix Composites (CMC) 12
2.2.2.3 Polymer Matrix Composites (PMC) 13

2.3 Types of Polymer Matrices 14
2.3.1 Thermosets 14
2.3.2 Thermoplastics 15
2.3.3 Advantages of Thermoplastics over Thermosets 16

2.4 Polypropylene (PP) 17
2.4.1 Synthesis and Structural isomers of Polypropylene 18
2.4.2 Chemical and Physical Properties of Polypropylene 20

2.5 Fiber 22
2.5.1 Natural fiber vs Synthetic fiber 24
2.5.2 Fiber Orientation and Woven Fabrics 24

2.6 Denim Textile 28
2.6.1 Composition of Denim Textile 29
2.6.2 Denim Dyes 30
2.6.2.1. Indigo Dye 30
2.6.2.2 Synthesis of Indigo 31
2.6.2.3.Chemical Reduction 31
2.6.2.4 Chemical Properties and Bond Structure of Indigo 33

2.6.3 Denim textile Properties 34
2.6.3.1.Dimensional Stability 34
2.6.3.2 Tear Strength 36
2.6.3.3.Wear and Durability 36
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2.6.4 Types of Denim 36
2.6.5 Review of Previous Researches 38
2.6.6 Application of Waste Denim Fiber Composites 40
2.6.7 Probable benefits from using Denim waste 41

2.6.7.1 Earnings from the wastes 42

Chapter 3 43

Experimental 43

3.1 Materials 43
3.1.1 Polymer Matrix 43
3.1.2 Denim Textile 43
3.1.3 Moisture Removal 44

3.2 Fabrication of Composites 44
3.2.1 Casting of PP 44
3.2.1.1 Hot Pressing 45
3.2.2 Fabrication of (PP) and Denim Fiber reinforced Composites 46

3.3 Tensile Test 47
3.4 Flexure Test 50
3.5 Hardness Test 52
3.6 Fourier Transform Infra-Red (FTIR) Spectroscopy 53
3.7 Thermo-Gravimetric Analyzer (TGA) Analysis 53
3.8 Field Emission Scanning Electron Microscopy (FESEM) Analysis 54

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Chapter 4 55

Results and Discussion 55

4.1 Mechanical Properties of PP 55
4.1.1 Tensile Properties of PP 55
4.1.2.Flexure Properties of PP 56

4.2 Tensile Properties of Denim Fiber 56
4.3 Effect of Fiber-Reinforcement on the Properties of PP 58

4.3.1 Effect of Fiber-Reinforcement on Tensile Properties of PP 58
4.3.2 Effect of Fiber-Reinforcement on Flexure Properties of PP 61
4.3.3 Hardness of PP and PP-denim fabric Composite 64

4.4 SEM Analysis of Fracture Surfaces of PP and the Composites 65
4.4.1 SEM Analysis of Pure PP Fracture surface 65
4.4.2 SEM Analysis of the PP+Discontinuous and randomly Oriented Denim
Fiber Composite Fracture surface 67
4.4.3 SEM Analysis of the PP+Continuous and Unidirectionally Oriented Denim
Fiber Composite Fracture surface 68

4.5 TGA Analysis of PP and the Composites 70

4.6 FTIR Analysis of Pure PP and Fiber-Reinforced composites 72
4.6.1 FTIR Analysis of PP 72
4.6.2 FTIR Analysis of Denim fiber 73
4.6.3 FTIR Analysis of Denim Fiber and PP Composites 74

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