Properties of 1-butyl-3-methylimidazolium chloride

(BMIMCL) Treated Sawdust-Reinforced Polyethylene

Composite

ABDULLAH BIN OTHMAN

E16A0004

A report submitted in partial fulfilment of the requirements for the

degree of Bachelor of Applied Science (Materials Technology)

with Honours

FACULTY OF BIOENGINEERING AND TECHNOLOGY

UMK

2020

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DECLARATION

I declare that this thesis entitled “Properties of 1-butyl-3-methylimidazolium chloride

(BMIMCL) Treated Sawdust-Reinforced Polyethylene Composite” is the results of my

own research except as cited in the references.

Signature : __________________________

Student’s Name : __________________________

Date : __________________________

Verified by:

Signature : ___________________________

Supervisor’s Name : ___________________________

Stamp : ___________________________

Date : ___________________________

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ACKNOWLEDGEMENT

First and foremost, praises and thanks to Allah, the Almighty for His showers of

blessings throughout my research work to complete the research successfully.

I would like to express my gratitude to my dedicated supervisor, Dr Asanah Binti

Radhi and my co-supervisor, Dr Hidayani Binti Jaafar for supervised and guided me to

complete the research and complete the thesis.

In addition, I would like to thanks my beloved parents, En Othman Bin Ekhwan

and Pn Jemaah Binti Ahmad Gemban for supported me mentally and physically during

my Bachelor Degree study. They also supported the financial, endless love and

encouragement for me throughout my study.

Last but not least, I would like to thanks all my friends, classmate, staff of

Faculty Bioengineering and Technology and to all peoples who help me to complete the

research work directly or indirectly.

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Properties of 1-butyl-3-methylimidazolium chloride (BMIMCl) Treated

Sawdust-Reinforced Polyethylene Composite

ABSTRACT

In this research, composites based on untreated, treated sawdust and pre-treatment on

treated sawdust with Polyethylene (PE) were prepared using injection moulding machine.

Raw sawdust was chemically treated with 1-butyl-3-metylimidazeluim Chloride

(BMIMCL) and Cetyl Trimethyl Ammonium Bromide (CTAB) to improve the properties

of composites. The amorphous and crystallinity were studied using X-Ray Diffraction

(XRD). Results from flexural testing and tensile testing that indicate mechanical

properties enhanced when pre-treated occurred on sawdust reinforced PE composites

compared to without pre-treatment. The surface morphologies obtain from Field

Emission Scanning Electron Microscope (FESEM) possess surface roughness and weak

interfacial adhesion, while the pre-treatment sawdust with CTAB showed improved in

filler-matrix interaction. This indicate that better dispersion of the sawdust with PE matrix

occurred upon chemical treatment of sawdust.

Keywords: Sawdust, Polyethylene, BMIMCL, CTAB, Biocomposites

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Sifat-sifat 1-butil-3-methylimidazolium klorida (BMIMCL) dirawat

serbuk kayu diperkukuh polietilena sebagai komposit

ABSTRAK

Dalam kajian ini, perbandingan komposit antara serbuk kayu tidak dirawat, serbuk kayu

dirawat dan serbuk kayu pra-rawatan dicampur dengan Polietilena (PE) telah disediakan

menggunakan suntikan mesin. Serbuk kayu telah dirawat dengan 1-butil-3-

metylimidazeluim Klorida (BMIMCL) dan Cetyl trimethyl ammonium bromida (CTAB)

untuk meningkatkan sifat-sifat komposit. Amorfos dan kristalin di analisis menggunakan

pembelauan sinar-X (XRD). Keputusan dari ujian lenturan dan ujian tegangan

menunjukkan bahawa sifat mekanikal dapat ditingkatkan apabila pra-rawatan serbukkayu

diperkukuh PE sebagai komposit berbanding tanpa pra-rawatan terhadap serbuk kayu.

Berdasarkan morfologi permukaan komposit dengan menggunakan pemancaran medan

mikroskopi imbasan elektron (FESEM), memiliki ikatan permukaan yang lemah

manakala serbuk kayu yang mengalami pra-rawatan menunjukkan interaksi antara

permukaan pengisi dan matriks dengan baik. Ia membuktikan bahawa penyebaran yang

lebih baik telah berlaku antara serbuk kayu dan PE ketika berlakunya rawatan kimia

terhadap serbuk kayu.

Kata kunci: Serbuk Kayu, Polietilena, BMIMCL, CTAB, Biokomposit

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TABLE OF CONTENT

DECLARATION ............................................................................................................. i

ACKNOWLEDGEMENT ............................................................................................. iii

TABLE OF CONTENT ................................................................................................. vi

LIST OF TABLES ......................................................................................................... ix

LIST OF FIGURES ........................................................................................................ x

LIST OF ABBREVIATIONS ...................................................................................... xii

LIST OF SYMBOLS ................................................................................................... xiii

CHAPTER 1 .................................................................................................................... 1

INTRODUCTION .......................................................................................................... 1

1.1 Background of Study ................................................................................... 1

1.1 Problem Statement ....................................................................................... 3

1.2 Objectives .................................................................................................... 3

1.3 Scope of Study ............................................................................................. 4

1.4 Significances of Study ................................................................................. 4

CHAPTER 2 .................................................................................................................... 5

LITERATURE REVIEW .............................................................................................. 5

2.1 Sawdust ........................................................................................................ 5

2.2 Polyethylene (PE) ........................................................................................ 6

2.3 Composition of Sawdust .............................................................................. 7

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2.3.1 Cellulose .......................................................................................... 7

2.3.2 Lignin ............................................................................................... 9

2.4 The used of Sawdust in Biocomposites ..................................................... 10

2.5 Properties of Biocomposites ...................................................................... 10

2.5.1 Mechanical ..................................................................................... 10

2.5.2 Morphology ................................................................................... 11

2.6 Surface Modification of Sawdust .............................................................. 12

2.6.1 Cetyltrimethylammonium bromide (CTAB) treated sawdust ....... 12

2.6.2 Silane treated sawdust .................................................................... 13

2.7 Pre-Treatment of Sawdust ......................................................................... 13

CHAPTER 3 .................................................................................................................. 15

MATERIALS AND METHODS ................................................................................. 15

3 ............................................................................................................................... 15

3.1 Research flowchart .................................................................................... 15

3.2 Materials .................................................................................................... 16

3.3 Methodology .............................................................................................. 16

3.3.1 Pre-treatment of sawdust ............................................................... 17

3.3.2 Modification of Sawdust ................................................................ 18

3.3.3 Fabrication of composites .............................................................. 18

3.3.4 Characterization ............................................................................. 19

CHAPTER 4 .................................................................................................................. 21

RESULTS AND DISCUSSION ................................................................................... 21

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4.1 Fourier Transform Infrared (FT-IR) Test Results ..................................... 21

4.2 X-Ray Diffraction (XRD) Analysis ........................................................... 24

4.3 Mechanical Testing.................................................................................... 26

4.4 Surface Morphology Analysis ................................................................... 30

CHAPTER 5 .................................................................................................................. 35

CONCLUSIONS AND RECOMMENDATIONS...................................................... 35

5.1 Conclusion ................................................................................................. 35

5.2 Recommendations ..................................................................................... 36

REFERENCES .............................................................................................................. 38

APPENDIX A ................................................................................................................ 41

APPENDIX B ................................................................................................................ 42

APPENDIX C ................................................................................................................ 43

APPENDIX D ................................................................................................................ 44

APPENDIX E ................................................................................................................ 45

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LIST OF TABLES

Table 4.1: FT-IR bands of the untreated sawdust and treated sawdust. ......................... 23

Table 4.2: Percentage of amorphous and crystallinity between untreated and treated

sawdust…………………………………………………………………………………25

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LIST OF FIGURES

Figure 2.1: Structure of Cellulose (O’sullvian, 1997) ....................................... 8

Figure 2.2: Hydrogen link to cellulose structure (Zhbankov et al., 2002) ........ 8

Figure 2.3: Lignin Structure (Liu, Hu, Zhang, & Xiao, 2016) .......................... 9

Figure 2.4: CTAB structure (Li, Guo, Bao, & Gao, 2011) .............................. 12

Figure 2.5: Silane structure (Vennerberg, Rueger, & Kessler, 2014) ............. 13

Figure 2.6: Structure of 1-butyl-3-metylemidazelium chloride……………….14

Figure 3.1: Sri Lakota Sdn Bhd ....................................................................... 17

Figure 3.2: Sawdust produce by Sri Lakota Sdn Bhd ..................................... 17

Figure 4.1: FT-IR analysis on treated and untreated sawdust ......................... 21

Figure 4.2: The XRD pattern results for untreated and treated sawdust. ........ 24

Figure 4.3: Flexural strength of PE, untreated sawdust and treated sawdust

........................................................................................ Error! Bookmark not defined.

Figure 4.4: Tensile result for untreated and treated sawdust ........................... 27

Figure 4.5: Elongation at break graph of tensile test ....................................... 28

Figure 4.6: Young’s Modulus of Tensile test .................................................. 28

Figure 4.7: Surface of untreated sawdust reinforced PE composites 500 x

magnification…………………………………………………………………………...30

Figure 4.8: Surface of sawdust treated CTAB reinforced PE composites 500 x

magnification .................................................................................................................. 31

Figure 4.9: Surface of treated sawdust CTAB with pre-treatment BMIMCL

reinforced PE composites at 500 x magnification .......................................................... 31

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Figure 4.10: Surface of sawdust treatment with BMIMCL at 1000 x

magnification .................................................................................................................. 32

Figure 4.11: Surface of pre-treatment sawdust with BMIMCL and treated

CTAB 1000 x magnification. .......................................................................................... 33

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LIST OF ABBREVIATIONS

1. FT-IR Fourier Transform Infrared Spectroscopy

2. XRD X-Ray Diffraction

3. FESEM Field Emission Scanning Electron Microscopy

4. CTAB Cetyl Trimethyl Ammonium Bromide

5. BMIMCL 1-butyl-3-metylimidazelium Chloride

6. PE Polyethylene

7. SD Sawdust

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LIST OF SYMBOLS

1. g Gram

2. °C Degree Celsius

3. μm Micro metre

4. % Percentage

5. wt% Weight percentage

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CHAPTER 1

INTRODUCTION

1.1 Background of Study

Sawdust is a tiny particle of wood that are formed from sawing or sanding wood.

It also known as wood dust. There are many ways to produce sawdust such as sawing,

milling, planning, routing, drilling and sanding. Sawdust can get from wood factory

or other industrial place where they used wood as their source. Factories usually will

throw away the wood dust because it categorized as a waste after their sawing process.

However, composite material can be created from sawdust. Therefore, rather than

thrown away, sawdust can be collected and develop a new product that can give

benefits to people in their lives.

Biocomposites is a material that contain matrix and reinforced by natural fiber.

Fabrication of biocomposites are more encourage because of these natural fiber mimic

the structure living materials properties. In this study, sawdust will be used as the

natural fiber reinforcement in matrix. There are not only inexpensive and durable, but

there can minimize environmental problem due to biodegradability properties. The

reinforced composites polymer that applied on natural fiber offers effectively in

healthy environment aspect.

Many ways were developed to enhance the properties of natural fiber composites.

Some studies have been revealed that natural fillers-reinforced with polymer

composites can increase the mechanical properties when suitable compatibilizers

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applied during composite fabrication. Sawdust was one of the natural sources that

widely used to improve the properties of biocomposites. However, there is a wide

polarity gap between fiber and matrix. It will difficult to fabricate wood interfacial

adhesion biocomposites and mechanical properties. This factor also will affect the

properties performance of the biocomposites.

The problem can be overcome by modifying the fiber’s surface property that

contains hydrophobic and hydrophilic act as bridge between fiber and matrix

(Shamsuri et al., 2014). Surface treatment process will be applied to modify the

surface of fiber. This process will help to minimize the polarity gap between fiber and

matrix. Replacement of polar hydroxyl group from the cellulose by addition of a

suitable interface modifier during fabrication of biocomposites can overcome the

problem. The compatibility between fiber and matrix will be improved. It is essential

to minimize the polarity gap in order to improve the properties of biocomposites

(Islam & Islam, 2015).

The fiber surface modifiers that chemically link with polymer through their

hydrophobic end show the interaction hydroxyl group and cellulose from the sawdust.

Surface modification process substantially minimizes the polarity gap between

hydrophilic fiber and hydrophobic polymer matrix. There will be an improvement in

the mechanical properties of the resultant composite occurs due to better dispersion

of fiber in the matrix and more effective interfacial adhesion, effective stress transfer

efficiency from the matrix to the fiber, and better wetting of the fiber by the matrix

that reduces micro voids at the fiber–matrix interface.

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1.1 Problem Statement

Composites materials are widely used in industry and people surrounding. There

are many efforts on development of new technology to enhance the properties of

biocomposites materials. Natural fiber has been one of sources that they used because

the properties more environmentally friendly. However, the hydrophobic and

hydrophilic nature of material has been an issue in order to produce the

biocomposites. In past study, the increase in the sawdust content increases possibility

of the formation of micro spaces in the filler matrix interfacial region and fiber

agglomeration due to preferential fiber-fiber interaction(Islam & Islam, 2011). The

factor of wide polarity gap between the natural fiber and the matrix caused the low

performance on the biocomposites properties.

1.2 Objectives

The objective of this study as follows:

1. To study the effect of 1-butyl-3-methylimidazolium chloride (BMIMCL) on the

surface modification of sawdust treatment with cetyltrimethylammonium bromide

(CTAB).

2. To modify the sawdust using CTAB.

3. To study the chemical and mechanical properties of 1-butyl-3-methylimidazolium

chloride (BMIMCL) Treated Sawdust-Reinforced Polyethylene Composite.

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1.3 Scope of Study

In this study, sawdust will be treated with ionic liquid and CTAB. The treatment

of sawdust with ionic liquid will increase the number of hydroxyl group. The wide

polarity gap between sawdust and PE can be reduce after the treatment process. The

increasing of hydroxyl group will increase the efficiency of the surface modification. In

this study, the natural fiber used which is sawdust as reinforcement and PE will use as

matrix. The properties strength of the treated sawdust-reinforced polyethylene composite

will enhance due to the sawdust treatment. The structural, mechanical and thermal

properties of biocomposites will analyse by using SEM, UTM and TGA respectively.

1.4 Significances of Study

The hydroxyl group that contain in sawdust will be increase after it treat with ionic

liquid. The composition of structure will also change after it will treat. The polarity gap

can be reduced. The surface modification definitely makes the compatibility of sawdust

and PE enhance, therefore increasing in strength of the biocomposites. The bridge

between the matrix and reinforcement after treatment process will help to enhance the

interfacial adhesion between sawdust and PE. Furthermore, the biocomposites properties

will improve in many factors such as mechanical, physical and morphology properties.

In addition, by using sawdust as a natural fiber and a waste from industry, this research

can sustain the Malaysia environment to reduce waste and recycle to produce new

product.

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CHAPTER 2

LITERATURE REVIEW

2.1 Sawdust

Sawdust or also known as wood dust is a waste product receives from

woodworking operation such as sawing, grinding, drilling and sanding. Basically, sawing

process will produce more sawdust in industry after their work, there is also other ways

or materials depend on their material they sawed. Most of the sawdust, they reused the

waste to produce wood composites.

Physically, sawdust that known as by-product from wood will have same

properties as wood itself. In industrial, sawdust will be decomposed by burning or

disposed, in other way, the usage of sawdust will help to reduce burning process and can

be reuse as fabrication of composites. The usage of waste sawdust also will help reduce

the usage of new sawdust to use in work field. The main chemical components

of sawdust are carbon (60.8%), hydrogen (5.2%), oxygen (33.8%), and nitrogen (0.9%).

The sawdust is primarily composed of cellulose, lignin, hemicelluloses, and minor

amounts (5–10%) of extraneous materials (Horisawa,1999).

Wood also known with its porosity factor because of its fibrous tissue. It

can be found in roots and stems of the trees. The organic material consists in natural fiber

composites of cellulose fibers embedded in matrix of lignin with resist compression. The

sawdust consists the woody layer. All the components were bound together in a complex

structure (Agbor, Cicek, Sparling, Berlin, & Levin, 2011).

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The cell walls polymers which are cellulose, hemicellulose and lignin that will

modified and expected will change the properties of the resource. This will be the basis

for chemical modification on the surface if the treatment applied will change properties

and also the performance of sawdust. The chemical structure of cellulose will be disrupted

by formation of O-H bonding between hydroxyl of cellulose and ion on ionic liquid.

Pre-treatment are needed for the process to extract lignocellulose. There is study

that stated that ionic liquid dissolve in many agriculture biomasses. The sawdust can be

treated with ionic liquid to change the content of biomass. In past research, there is study

about treatment of ionic liquid with oil palm frond (OPF). The result was observe using

FT-IR and difference in treated and the untreated OPF. In this case, the FT-IR will obtain

the functional groups presents and chemical changes in treated sawdust.

As the result from past study, it showed that ionic liquid had successfully extracted

and the sample properties were enhanced. The ionic liquid dissolution pre-treatment

showed better dissolution due to high hydrogen basicity while anion acetate plays a key

role of dissolution. It proves that ionic liquid was suitable to use for chemical treatment

due to environmentally properties of ionic liquid. The implementation of waste sawdust

could also be generalized to the use of fabricate composite, which could lead to an

environmental saving profit (Memon., 2017).

2.2 Polyethylene (PE)

Polyethylene is a thermoplastic polymer with variable crystalline structure and an

extremely large range of applications depending on the particular type. It is one of the

most widely produced plastics in the world. Since 2017, over tens of millions of tons are

produced worldwide to produce plastic. Its primary use is in packaging which are plastic

bags, plastic films and containers including bottles.

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There are three types of PE which is High Density Polyethylene (HDPE), Low

Density Polyethylene (LDPE) and Ultrahigh Molecular Weight Polyethylene (UHMW).

HDPE is much more crystalline, has a much higher density, and is often used in

completely different circumstances than LDPE. HDPE can withstand about 115 °C to 135

°C. The application of LDPE is widely used in plastic packaging such as for grocery bags

or plastic wrap. HDPE by contrast has common applications in construction for example

in its use as a drain pipe. UHMW has high performance applications such as medical

devices and bulletproof vests.

2.3 Composition of Sawdust

Sawdust contain of cellulose, lignin, hemicellulose and small amount (5-10 %)

of extraneous materials.

2.3.1 Cellulose

Cellulose is one of the most abundance polymers nowadays. It is an important

structural component of primary cell wall and of plants and woods. The long chain of

linked sugar molecules gives the high strength on the wood. Additionally, it acts as cell

wall for plants. (C6H10O5) n is the chemical formula which contain polysaccharides linear

chain β (1→4) linked D-glucose units (Agbor et al., 2011). In figure 2.1, shows the

cellulose, a linear polymer of D-glucose units linked by β (1→4) glycocidic bonds.

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Figure 2.1: Structure of Cellulose (O’sullvian, 1997)

Figure 2.2 shows the hydrogen link of cellulose. Cellulose are an odourless that

have hydrophilic nature with contact angle of 20-30 degree and it was insoluble in water

however it is biodegradable. It is more crystalline compared to starch and in order to

become amorphous in water, in past study stated that it required 320°C and pressure of

250 MPa. By undergoes chemical treatment, the cellulose I to cellulose II.

Figure 2.2: Hydrogen link to cellulose structure (Zhbankov et al., 2002)

The properties of cellulose that low-cost, non-toxic and biodegradable make it as

environmental friendly (A. A. Shamsuri, Abdullah, & Daik, 2012). Natural fibers possess

moderately higher specific strength than synthetic fibers. There are found in product since

natural fiber as a source such as risk husk, sawdust, and corn cob. There are not only

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inexpensive and durable, but there can minimize environmental problem due to

biodegradability properties.

2.3.2 Lignin

Lignin is a class of complex organic polymers that form key structural materials

in the support tissues of vascular plants and some algae. Lignin are particularly important

in the formation of cell walls, especially in wood and bark, because they lend rigidity and

do not rot easily. Chemically, lignin is cross-linked phenolic polymers. Most commonly

was used as support through strengthening of wood which mainly composed of xylem

cells and lignified sclerenchyma fibers in vascular plants.

Pure lignin usually in amorphous form consisted aromatic ether backbone that

can be potential substrates for the production of aromatic chemicals. (Chakar &

Ragauskas, 2004). Lignin can isolate in large quantity from lignocellulosic material by

dilute acid, alkaline treatment or sulphite pulping process. However, ionic liquids have

widely used as new green solvents because of its environmentally friendly and it used to

dissolve complex macromolecules and polymeric materials.

Figure 2.3: Lignin Structure (Liu, Hu, Zhang, & Xiao, 2016)

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2.4 The used of Sawdust in Biocomposites

Nowadays, fabrication of biocomposites are developed in many industrial

compared to normal composite. Composite which contain at least two materials which is

matrix and reinforcement. In this study, the matrix is sawdust from hardwood and

reinforced by Polyethylene (PE) from type of polymer. There will be a treatment for the

sawdust before it fabricates as a biocomposites. The advantage using sawdust in

biocomposites is the properties can be enhanced due to the sawdust itself from natural

source.

The sawdust that from natural source has properties in strength like hardwood

plant. It consists of cellulose microfibrils embedded in an amorphous matrix of lignin and

hemicellulose. Cellulose contain in sawdust which hydrophilic nature but does not absorb

water will help to improve the absorption properties on biocomposites. Besides, usage of

sawdust waste will help reduce waste in the industry and the biocomposites produce is

environmentally friendly.

2.5 Properties of Biocomposites

Polyethylene (PE) will use in this study as reinforcement for biocomposites. The

fabrication of biocomposites will mix the treated sawdust and the PE. The properties will

be observed based on thermal, physical, mechanical and morphology properties change

after fabrication of biocomposites.

2.5.1 Mechanical

Mechanical factors will show the strength of the biocomposites. The

biocomposites will be tested using Universal Testing Machine (UTM). There is research

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study of bamboo as natural fiber for biocomposites. The result shows composite with 10

% bamboo fibers and 10 % glass fibers had 21 % and 31 % increase in tensile strength

and tensile modulus respectively, compared with 20 % increase in strength when using

bamboo fibers (Miao & Hamad, 2013). UTM is a universal machine that can do more

than one testing such as tensile testing, flexural testing or also known as 3-point bending

testing and compression test. In this study, the treated sawdust reinforced by PE will be

test using UTM to study there is any improvement on the biocomposites strength between

the treated and the untreated sawdust.

2.5.2 Morphology

Morphology analysis is a study of the surface of material. Scanning Electron

Microscope (SEM) will be used. The different surface of biocomposites treated sawdust

and the untreated sawdust will observe using SEM. There will be difference on the surface

because surface modification will be applied on the sawdust. In the past study, the result

shows that the CTAB treated sawdust reinforced PE has low hydrophilic nature compared

to the untreated sawdust reinforced PE. It shows that the SEM can be study the porosity

of biocomposites and the hydrophilic nature of biocomposites can be improved by surface

treatment of sawdust. There is research shows that raw sawdust–PP composites possess

surface roughness with extruded filler moieties, and weak interfacial adhesion between

the matrix and the filler while the chemically treated one showed improved filler–matrix

interaction (Rezaur Rahman, Nazrul Islam, & Monimul Huque, 2010).

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2.6 Surface Modification of Sawdust

Surface modification is a method to improve the properties of original sawdust

by altering the chemical nature of the sawdust (Petrič, 2013). Thus, properties of materials

source of sawdust may enhance and produce a good quality depends on product form.

2.6.1 Cetyltrimethylammonium bromide (CTAB) treated sawdust

Cetyltrimethylammonium bromide (CTAB) is a quaternary ammonium

surfactant. The cation is an effective antiseptic agent against bacteria and fungi. CTAB is

a cationic detergent, soluble in H2O and readily soluble in alcohol. CTAB is commonly

used in the preparation and purification of genomic DNA from bacteria including DNA

mini preps for sequencing. CTAB complexes with both polysaccharide and residual

protein. Purpose treatment of sawdust with CTAB was expected to enhance the properties

of the sawdust. Figure 2.4 shows the chemical structure of CTAB.

Figure 2.4: CTAB structure (Li, Guo, Bao, & Gao, 2011)

Surface modification on natural fiber usually will treat with CTAB. The

properties of sawdust will improve based on the past research. The result shows CTAB

surfactant treated reinforced composites had slight greater elongation compared to the

untreated sawdust (Md Sakinul, 2011). After the sawdust treat with CTAB, the surface

structure will change and the properties of sawdust will improve.

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2.6.2 Silane treated sawdust

Silane or also known as Silicon Hydride is a compound that contain silicon and

hydrogen. The simplest silane, monosilane (SiH4) and is also the most stable. The

properties of colourless gas that liquefies at -112 °C and freezes at -185 °C. It decomposes

slowly at 250 °C, rapidly at 500 °C. Figure 2.5 shows the silane structure.

Figure 2.5: Silane structure (Vennerberg, Rueger, & Kessler, 2014)

Silane treatment was applied in past research. In example, there are two silane

coupling agents used in past study which is N-(3Trimethoxysilylpropyl)

diethylenetriamine and γ-aminopropyl trimethoxy silane. The research found that there is

improvement in interfacial adhesion upon wood surface modification (Brostow., 2016).

As the wood contents were raised, a comparatively smaller interfacial area between

hydrophilic filler and hydrophobic matrix polymer could be witnessed by scanning

electron technique (Wimonsong, Threepopnatkul, & Kulsetthanchalee, 2012).

2.7 Pre-Treatment of Sawdust

The pre-treatment of sawdust is a process done before sawdust was treated with

CTAB. In this study, the pre-treatment use is 1-butyl-3-methylimidazolium chloride

(BMIMCL). It is also known as ionic liquid. Ionic liquid is new solvent that is

environmentally and does not harmful towards users and woods. Environmentally

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friendly organic solvents for a wide range of biopolymers and synthetic polymers, due to

their high chemical stability and low volatility (Croitoru & Patachia, 2015). The ability is

same like alkali but in their own way to treats woods. Its properties that does not degrades

the woods might help to improve the properties of wood and better than alkali. Ionic

liquids will serve as reaction media in effectively removing lignin and hemicellulose as

well as reducing cellulose crystallinity (Darji & Som, 2013). The ionic liquids have

unique properties which are low density simultaneously with high mechanical strength,

low cost, biodegradability and chemical stability. It can dissolve many organic and

inorganic materials due to these properties. Figure 2.6 shows the 1-butyl-3-

metylemidazelium chloride chemical structure.

Figure 2.6: Structure of 1-butyl-3-metylemidazelium chloride (Saha, Hayashi, Kobayashi, &

Hamaguchi, 2003)

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CHAPTER 3

MATERIALS AND METHODS

3.1 Research flowchart

Surface Morphology

Stage 1

Stage 3

Stage 2

Sawdust obtains from Sri Lakota Sdn Bhd

Wash and dry it in oven for 24 hours at 110 °C

Dried sawdust will keep and seal in container

Clean and dried sawdust and will treat

with ionic liquid then treat with CTAB

Dried in oven at 110 °C and observe using FT-IR and XRD

Mixed treated sawdust with PE Pellets at ratio of 30:70

The mixture will pass through extruder with temperature of

180 ℃. Then dried in oven for 1 hour at 80 ℃.

Injection moulding at 180 ℃ will use to produce sample for mechanical

testing

Characterization

Mechanical Testing

Treat with CTAB

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3.2 Materials

Polyethylene (PE) pellet was bought from sigma, 4 kg of hardwoods sawdust was

collected from local industry in Jeli, Sri Lakota Sdn Bhd. The sawdust has been washed

and sieve with 300 μm. The chemical used to treat sawdust are ionic liquid (1-butyl-3-

methylimidazolium chloride) and 1000 ml of 0.5% cetyltrimethylammonium bromide

(CTAB) was obtained from UMK laboratory. The sawdust that been treated by different

parameter will characterize using Fourier transform infrared spectroscopy (FT-IR).

3.3 Methodology

Sawdust was collected from Sri Lakota Sdn Bhd located at Jeli based on Figure

3.1. The sawdust shown on Figure 3.2 was the industrial waste and the source from

Timber tree which is one of the type hardwoods trees. The sawdust has been washed and

all the wood fragments was moved from the sawdust. Auto Sieve Shaker machine was

used during sieving process occur at Animal Lab, University Malaysia Kelantan. The

sawdust was sieved using 300 μm size. This process was to remove any lumps contain in

the sawdust. After getting the fine sawdust powder, the sawdust was dried in an oven at

110 ℃ for 24 hours then it will keep in zipper plastic bag. In order to avoid from moisture,

silica gel was put together but in different plastic that has hole.

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Figure 3.1: Sri Lakota Sdn Bhd

Figure 3.2: Sawdust produce by Sri Lakota Sdn Bhd

3.3.1 Pre-treatment of sawdust

The dried sawdust was treated with 5% of aqueous solution ionic liquid in the pre-

treatment process. 250 g of sawdust will mix with 1000 g of ionic liquid (1-butyl-3-

methylimidazolium chloride). It was set up by preparing oil bath which 200 ml of Blue

Hill Oil Minyak Kelapa Sawit was used in the process. The sawdust was added gradually

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in ionic liquid preheated in an oil bath at 90 ℃ in a closed container. The sawdust treated

with ionic liquid was stirred continuously at 90 ℃ for 8 hours a day. This process takes

about 4 days to complete. On the next morning, the sample will be solidified, to make it

as actual form, it needs to heat again at 90 ℃ for 30 minutes and stir it again constantly.

Then, the sawdust has been washed simultaneously by immersed the mixture in distilled

water at room temperature. A lot of distilled water needed to remove the oil from the

sawdust to avoid error from happen during FT-IR spectral analyse. The complete sawdust

treated ionic liquid will be obtained between 30 to 32 hours.

3.3.2 Modification of Sawdust

After the process of pre-treatment, both of the sawdust that has been treated and

the untreated sawdust was treated with 1000 ml of 10 % CTAB for 30 minutes. 100 g of

sawdust was mix with 10 % CTAB. During mixing process, the beaker was put on hot

plate and temperature were controlled between 35 ℃ to 40 ℃. Both processes take 30

minutes to fully treated. The sample was taken out after the process, then it has been

washed by using distilled water before it dried in an oven at 110 ℃ for 24 hours. The

treated and the untreated sawdust was analysed by using FT-IR (Thermo Fisher Nicolet

iS20 FTIR Spectrometer) to study the spectral and XRD machine (Bruker’s X-Ray

diffraction and Scattering) for study amorphous and crystallinity of the specimen.

3.3.3 Fabrication of composites

PE pellets was mixed with sawdust with different ratio which is (30/70) wt.%.

Based on the ratio used, 210 g of sawdust need to mix with 490 g PE are needed to form

each of the untreated and treated sawdust composites. Addition of another 700 g of PE

also needed for purging process. In this process, Single Screw Extruder machine and

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Granulator machine (Brabender GMBH & CO.KG, D-47055 Duisburg, Germany) was

used for extrusion process and cut into granule shape. There are 4 zones in the extruder

machine and difference temperature at each zone. The first zone is fit zone which is 180

℃, transition zone at 220 ℃, metering zone at 220 ℃ and dye zone which is 225 ℃. The

screw speed was set 55 rotation per minute (rpm). The mixture was poured into extruder

machine at 180 ℃. The extruder composite produced a cutting product sample that length

of 2 cm longs pieces. Then, the product sample from extruder was dried in oven at 1 hour

with 80 ℃ of temperature. After that, the sample was sealed in a container and kept aside.

For mechanical testing, the dried granule has been prepared using injection moulding at

180 ℃. Mould temperature for Injection moulding is 35 ℃, cooling time 17 seconds,

screw speed for plasticizing is 195 rotation per minute (rpm) and injection speed is 70

mm/s. Six samples have been produced for treated and untreated sawdust and the average

reading was obtained.

3.3.4 Characterization

1. Structural and Chemical Testing

The infrared spectra analysis was conducted on treated sawdust and the untreated

sawdust. The infrared (IR) spectra of treated and untreated sawdust was observed using

Fourier transform IR spectrometer (FT-IR) model of (Thermo Fisher Nicolet iS20 FTIR

Spectrometer). The sample mixture pours on the structural cellulose was analysed after

treatment with ionic liquid. Functional groups and compound contain has been observed

and data was analysed based on absorption difference between treated and untreated

sawdust. Next, XRD model of (Bruker’s X-Ray diffraction and Scattering) also used for

study the amorphous and crystallinity structural contain between untreated and treated

sawdust.

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2. Mechanical Testing

Universal Testing Machine (5969 – 50 kN Elektro – Mechanical UTM) has been

used for testing the mechanical properties. The mechanical testing of the composites was

carried out according ASTM to make sure exact value will be receive after the test. The

tensile and flexural properties of injection-moulded specimen were measured with a

universal testing machine according to ASTM D 638 and ASTM D 790 respectively. The

dimension of sample for tensile is 148 x 10 x 4.1 mm3. Tensile testing has been conducted

to study the strength properties of biocomposites. The sample has been tested and

observed until the sample fails and breaks. It will show the result of tensile strength after

the testing. The measurements have been taken during the test and the characteristic of

the biocomposites while it is under a tensile load was revealed. The flexural test of the

specimen has dimension of 79 x 10 x 4.1 mm3 was tested by using the same machine.

Flexural test was conducted to study the maximum stress at the outermost fiber on either

the compression or tension side of the specimen. Flexural modulus is calculated from the

slope of the stress vs. strain deflection curve and modulus of rupture.

3. Morphology Analysis

The morphology of untreated and treated sawdust mix with PE will be analyse.

The surface ruptured of biocomposites after tensile testing were observe under High

Resolution Field Emission Scanning Electron Microscope (XHR - FESEM) model FEI

Various 460L. The samples were obtained from tensile test sample that has cross-

sectioned at room temperature. The morphologies were observed at magnification of 100

x, 200 x, 500 x and 1 000 x with accelerating voltages of 1.0 kV.

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CHAPTER 4

RESULTS AND DISCUSSION

4.1 Fourier Transform Infrared (FT-IR) Test Results

Figure 4.1: FT-IR analysis on treated and untreated sawdust

In order to gain more insights into the effects of BMIMCL pre-treatment, the study

on structural and chemical characteristics of untreated sawdust and treated sawdust are

essential. The pre-treatment sawdust had altered the chemical and structural

characteristics of the sawdust reinforced PE composites compared to the untreated

sawdust. The structural changes of regenerated cellulose were analysed by FT-IR

spectroscopy in the region of 500 – 4000 cm-1, which is commonly used to study the fine

structural characteristics of cellulose. The FT-IR spectra in figure 9 shows the untreated

0 500 1000 1500 2000 2500 3000 3500 4000 4500

Tra

nsm

itta

nce

%

Wavenumber (cm-1)

Sawdust rawSawdust + CTABSawdust + BMIMCLSawdust + BMIMCL+CTAB

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sawdust, sawdust treatment with CTAB, sawdust treatment with Ionic Liquid and sawdust

treated with Ionic liquid and CTAB. All the samples above show the different between

untreated sawdust and treated sawdust. There is different with the treated and untreated

sawdust can be detected in the infrared spectra in terms of different absorbance value and

shapes of the band’s location. It showed clearly the typical absorbance bands expected

for cellulose, hemicellulose and the peak of region of 500 cm-1 respectively used to study

fine structural characteristic of cellulose in sawdust (Hurtubise & Krassig, 1960). Spectra

of all regenerated cellulose show a strongest absorption band at range 1030 cm-1. This

band refer to the C-O stretching vibration in cellulose, hemicellulose and aryl group in

lignin.

Based on the figure 4.1, it shows the result of untreated sawdust that has been used

for reference and also comparison with treated sawdust. From the spectral above, the

result shows no difference when only pre-treatment with BMIMCL. As can be seen, the

strong absorption between 3400 and 3600 cm-1 in all FTIR spectra is caused by the

remaining OH groups of the fiber constituents (Cui, Lee, Noruziaan, Cheung, & Tao,

2008). There are also no differences between all four samples at range of 1030 cm-1

because all the samples show high absorption at that range.

However, the presence of CTAB make a big difference compared to untreated

sawdust and sawdust treated with BMIMCL only. All the samples have a similar trend

however the sawdust that undergoes pre-treatment and treat with sawdust revealed a

strong intensity broad bands in the range of 2850 cm-1 to 2970 cm-1. It shows the

degradation of cellulose also reduced C-H stretching at 2916 cm-1 and free/hydrogen-

bonded OH stretching at 3333.18 cm-1 of this regenerated cellulose. All the absorption

bands that occurred in the untreated sawdust were present in the treated sawdust spectra,

indicating that both have similar compositions. An obvious change in intensity was

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observed in the band of approximately 1030 cm-1. The transmittance of this band

increased in all the sawdust sample and has slightly difference with the untreated sawdust

samples. This indicates that the treated sawdust contained considerable amounts of

cellulose/ hemicellulose, and possibly lignin, after the ionic liquid pre-treatments.

Besides, this also implies that ionic liquid pre-treatment might dissolve components other

than cellulose/hemicellulose, whereby the relative cellulose/ hemicellulose content of

sawdust increases proportionately.

Table 4.1. FT-IR bands of the untreated sawdust and treated sawdust.

Sample O-H

Stretching

CH2

Stretching

CH2

Stretching

C-O Stretching

Untreated Sawdust 3333.18 2916.24 — 1030.0

Sawdust + BMIMCL 3334.0 2918.15 — 1030.6

Sawdust + CTAB 3337.18 2918.45 2849.89 1030.6

Sawdust + BMIMCL + CTAB 3336.09 2916.75 2848.96 1031.05

From Table 4.1, the intensity of O-H bonds in the region 3500 cm-1 and

3100 cm-1 has a difference when the treatment of Sawdust and CTAB and BMIMCL. This

implies that he hydrophilic nature of sawdust has significantly reduced after treatment

process, which paved the way on enhancing the interfacial adhesion between PE and

sawdust. In addition, it will increase the fiber-fiber interaction. It can be assumed that

there is increasing in mechanical properties of composite.

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4.2 X-Ray Diffraction (XRD) Analysis

Figure 4.2: The XRD pattern results for untreated and treated sawdust.

The X-ray diffract pattern above explain about crystallinity and amorphous

proportion between the untreated sawdust and treated sawdust. The stacked graph can be

observed as difference intensity between the untreated and treated sawdust. There is

slightly different if the raw sawdust compared to sawdust and BMIMCL. However, the

presents of CTAB in the treatment change the peak at 2 Theta = 24 where sawdust treat

with CTAB and also pre-treatment with BMIMCL has increase the peaks if intensity.

Based on the entire above pattern in Figure 4.2, the result between

untreated and treated sawdust, the XRD pattern shows a similar trend. The peak of

untreated sawdust is sharp and intense compare to treated sawdust. It is because the

untreated sawdust has higher crystallinity compared to treated sawdust which the

crystallinity has been reduced. Based on the data in Table 4.2, the percentage of

crystallinity and amorphous was calculated. The untreated sawdust shows 64.9 % of

10 20 30 40 50 60 70 80 90

Inte

nsi

ty

2 Theta

Sawdust raw

SD + BMIMCL

SD + CTAB

SD + BMIMCL + CTAB

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amorphous and 35.1 % of crystallinity. The sawdust that undergoes pre-treatment has

65.6 % amorphous and 34.4 % crystallinity.

The presence of CTAB in the rest of treatment has reduce the amorphous

percentage and increase the percentage of crystallinity. Sawdust treatment with CTAB

shows 54.0 % of amorphous and 46.0 % of crystallinity and the sawdust treated with

CTAB that undergoes pre-treatment with BMIMCL shows 57.9 % of amorphous and 42.1

% of crystallinity.

Table 4.2: Percentage of amorphous and crystallinity between treated and untreated sawdust.

Samples Amorphous (%) Crystallinity (%)

Untreated Sawdust 64.9 35.1

Sawdust + BMIMCL 65.6 34.4

Sawdust + CTAB 54.0 46.0

Sawdust + BMIMCL + CTAB 57.9 42.1

The peaks from diffract pattern indicates the untreated and treated sawdust that

amorphous and crystalline phase are exist in the sample. However, the sample that treated

with untreated shows different peak and changes in diffract pattern. Addition of

BMIMCL has slightly different then the treatment with CTAB makes the value of

amorphous and crystalline become difference on the treated sample.

These changes of diffraction peaks indicate the significant cleavage of hydrogen

bonds in cellulose, leading to the significant decrystallization of lignocellulose after

dissolution, chemical modification and regeneration. The peak of amorphous and

crystalline are losing it shape because the composition of sawdust had degraded and

change the rate of dissolution of treated sawdust (Ang, Ngoh, Chua, & Lee, 2012).

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4.3 Mechanical Testing

Figure 4.3: Flexural strength of PE, untreated sawdust and treated sawdust.

The flexural strength of a material is a measure of its ability to resist failure in

bending under the load given to the sample. It was performed to study the effect of

untreated sawdust fibre and treated sawdust fibre. Based on figure 4.3, it shows the

relationship between the untreated sawdust mix PE composites and treated sawdust with

PE composites. As can be seen, different flexural strength was shown by each sample.

The untreated sawdust mix PE composites show the highest flexural strength which is

32.6 MPa. However, the treated sawdust composite with CTAB shows decreasing in

flexural strength which is 26.0 MPa. The sawdust treated CTAB composites which

undergoes pre-treatment shows slightly increase which is 26.4 MPa.

Figure 4.3 shows the evident that both addition untreated sawdust and treated

sawdust in PE matrix has resulted an increase in flexural strength values of the

composites. In this case, significant improvement in flexural strength values was

0

5

10

15

20

25

30

35

PE PE + SD PE + SD + CTAB PE + SD + CTAB +

BMIMCL

Fle

xura

l S

tren

gth

(M

Pa)

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observed upon incorporation sawdust with PE as matrix in composites. The treated

sawdust that undergoes pre-treatment shows that there is effect of favourable mechanical

entanglement of polymer chain with the sawdust fiber. Since sawdust possess higher

modulus that PE matrix, it shows that higher stress and for all the samples for the same

deformation and increased the matrix interfacial adhesion provides for increased stress

transfer from matrix to fiber.

Figure 4.4: Tensile result for untreated and treated sawdust

Based on tensile strength on Figure 4.4, same pattern is show to the flexural

strength. Untreated sawdust mix with PE as composites show the highest strength which

is 18.4 MPa. Treated sawdust between the pre-treatment and without pre-treatment show

slightly difference which is 15.4 MPa and 15.8 MPa. Its shows that the pre-treatment

enhance the interfacial adhesion of sawdust treated CTAB with PE matrix. The treated

sawdust with CTAB shows a slightly decrease in both tensile and flexural strength were

rather unexpected. Previous researchers prove the positive effect of CTAB treatment on

sawdust. The different weight percentage may could lead to inhomogeneity and

0

2

4

6

8

10

12

14

16

18

20

PE + SD PE + SD + CTAB PE + SD + BMIMCL +

CTAB

Ten

sile

Str

ength

(M

Pa)

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insufficient coupling between matrix and fibers while exceed limit could form

agglomeration. Low tensile strength show on treated sawdust with CTAB shows that the

lack of adhesion between the fiber and the matrix of composites. The application of

BMIMCL act as coupling agent has improve the tensile strength composites compared to

untreated sawdust and treated sawdust without treatment reinforced PE composites.

Figure 4.5: Elongation at break graph of tensile test

Figure 4.6: Young’s Modulus of Tensile test

0

2

4

6

8

10

12

14

PE + SD PE+ SD + CTAB PE + SD + BMIMCL

+CTAB

Elo

nga

tio

n a

t B

reak

(%

)

Elongation at Break (%)

0

500

1000

1500

2000

2500

PE + SD PE + SD + CTAB PE + SD + BMIMCL +

CTAB

Yo

ung's

Mo

dulu

s (M

Pa)

Young's Modulus (MPa)

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Based on figure 4.5, it shows the increasing order of elongation percentage at

break. The untreated sawdust reinforced PE composites show 3.26 %, the treated sawdust

reinforced PE composites show 9.98 % and the treated sawdust reinforced PE with

undergoes pre-treatment BMIMCL shows the highest value which is 10.2 %. However,

Young’s modulus shows decreasing order between untreated and treated sawdust

reinforced PE composites. PE mixed with sawdust composites has 2280 MPa, PE mix

sawdust with treated CTAB shows 2080 MPa and treated sawdust reinforced PE with pre-

treatment shows 1810 MPa. As shown in result figure 4.5, the untreated sawdust has low

elongation at break. It has strong tendency which low in interfacial adhesion between

sawdust and PE, as the weak region increase, it could crack more easily that leads to

fracture, thus the energy of break may reduce too (Yang, Peng, Wang, & Liu, 2010).

Based on XRD analysis shown that the untreated has low crystallinity, therefore

it can be related to the Young’s modulus result. Recent study was reported that crystallites

possess higher modulus than the amorphous substances. (Sanadi, Caulfield, Jacobson, &

Rowell, 1995). Probably during the process on treatment, the fiber surface attains some

crystalline nature, which it dominates over bulks structure thus, the result shows higher

in strength. Based on (Hossain, Islam, & Islam, 2014), wood saw dust particle reinforced

polymer composites that treated with chemical treatment slightly improved the tensile

strength compared to untreated saw dust biocomposites. However, in this research, it

shows a different value but the pre-treatment and without pre-treatment shows an increase

value for both flexural and tensile strength. This may be mainly attributed to the poor

interfacial adhesion between the hydrophobic polymeric matrix of PE and the hydrophilic

lignocellulosic fillers, which does not allow efficient stress transfer between the two

phases of the material (Fakhrul, Mahbub, & Islam, 2013).

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4.4 Surface Morphology Analysis

In this analysis, Extreme High-Resolution Field Emission Scanning Electron

Microscope (XHR-FESEM) was used to study interfacial adhesion of biocomposites

between hydrophilic nature of sawdust and hydrophobic polymeric matrix PE. The

bending fracture surface of the PE and wood sawdust composites at a filler loading of 30

wt.% is shown in Figure 4 in which numerous cavities and pulled-out fibers can be seen.

The presence of these voids and pulled-out fibers confirms that the interfacial bonding

between the filler and the matrix polymer is occurred.

Figure 4.7: Surface of untreated sawdust reinforced PE composites at 500 x magnification

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Figure 4.8: Surface of sawdust treated CTAB reinforced PE composites at 500 x magnification

Figure 4.9: Surface of treated sawdust CTAB with pre-treatment BMIMCL reinforced PE

composites at 500 x magnification

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.

Figure 4.10: Surface of sawdust treatment with BMIMCL at 1000 x magnification

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Figure 4.11: Surface of pre-treatment sawdust with BMIMCL and treated CTAB 1000 x

magnification.

Based on Figure 4.7, the FESEM micrograph were shown between untreated

sawdust and Figure 4.8 and Figure 4.9 the treated sawdust reinforced PE composites.

Each unit of sawdust particle mainly consists of crystalline cellulose surrounded and

cemented together with hemicelluloses and lignin. These ultimate cells extend

longitudinally overlapping each other and form the cellular structure. The CTAB reacts

with hydroxyl group of cementing material hemicellulose, and it will change the cellular

structure of thereby the filler split into filament. The untreated show larger size of fiber

compared to treated sawdust reinforced PE composites.

Based on the FESEM image of untreated sawdust, it shows higher fibers pull-out

compared to the treated sawdust biocomposites. The formation of void is less compared

to the treated sawdust at the pull-out during tensile testing, therefore the it increases in

result of tensile strength of composites. It also proves that the interfacial adhesion at the

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surface between sawdust and PE matrix are in good interaction. In figure 16, irregular

size and non-uniform cross section may contribute to low in strength properties and low

interaction between sawdust and PE composites surface. The addition of BMIMCL act as

coupling agents appears to produce a significant improvement to the surface of

composites compared to without pre-treatment treated sawdust reinforced PE composites.

The pull-out of fiber obtained due to poor interfacial adhesion between sawdust fiber and

PE matrix (Ahmad Adlie Shamsuri et al., 2014).

However, due to strength in mechanical properties, is shows low in strength

because of void on surface towards the fracture force due to weak interaction of fiber and

matrix (Flores-Hernández et al., 2014). The result from the FESEM also indicates that the

presence of BMIMCL with CTAB increase the adhesion between fiber and PE matrix

which was the major reason for increase in toughness due to result elongation at break in

mechanical properties. Based on Figure 4.10 and Figure 4.11 with magnification of 500,

the treatment shows the morphology surface of treated sawdust. Figure 4.10 shows the

void formation higher however, it can be altered after treatment with CTAB which show

in the Figure 4.11, less formation of void occurred thus, the mechanical properties also

enhance in mechanical properties. The changes on structural surface were effect during

mixing with polymeric matrix PE, therefore, it can be related to the mechanical

properties’ changes on biocomposites during the mechanical testing.

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CHAPTER 5

CONCLUSIONS AND RECOMMENDATIONS

5.1 Conclusion

In this study, the sawdust was treated with BMIMCL and CTAB reinforced

polymer PE composites to compare the structural and mechanical properties composites.

Based on objective of this research, it is to study the effect of 1-butyl-

3mythylimidazolium chloride (BMIMCL) pre-treatment on sawdust. The pre-treatment

provides some advantages such as decrease the crystallinity of lignin content that help

improve hydrolysis efficiency and increase the surface area. The research also studies

about the treatment sawdust with CTAB. There are four characterizations to study the

changes on treated sawdust which is FTIR analysis, X-Ray diffraction analysis,

mechanical testing and surface morphology. Although the physical appearances do not

differ much, however the quality and characteristic of sawdust obtain show changes when

treated with BMIMCL and CTAB.

From FT-IR results, the treated sawdust shows a massive change value in

the spectra band of treated sawdust when compared to untreated sawdust. At range of

which shows the degradation of cellulose also reduced C-H stretching 2849 cm-1 and

free/hydrogen-bonded OH stretching 3333 cm-1. The result from XRD show that the

treated sawdust shows the increase in amorphous and decreasing in crystallinity

compared to untreated sawdust. Presence of CTAB in sawdust shows the highest changes

compared to another sample.

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In mechanical properties aspect, Universal Testing machine was used to study

the tensile strength and flexural strength. Based on mechanical properties of both tested

sawdust reinforced PE composites show great dependency on the strain rate applied. The

yield stress, compression modulus, and ultimate compressive strength were

proportionally increased as the strain rate increased. In past study show that untreated

sawdust has lower strength compared to treated sawdust. However, in this study,

untreated sawdust has the highest value in Tensile strength and Flexural strength. The

addition of wood sawdust as reinforcing material slightly decrease the strength of the pure

polymer from its pure state. It is due to difficulty of uniform mixing and distribution of

particle inside the matrix. The surface morphology was study using FESEM, and it show

that the strength is low because the interfacial adhesion between fiber and matrix in

treated sawdust is not form properly. Ultimately, post damage analysis was successfully

determined through fractographic analysis in order to understand the failure mechanism

experienced by these composite systems under both static and dynamic loading.

5.2 Recommendations

There was an equipment problem during the first step which is auto sieve

machine. Unfortunately, the machine breakdown and the siever torn away, then, sieving

process was manually done. It may other substance will mix with sample and also the size

may not same as expected. There is also problem with the temperature on hot plate

because it not constant. As inform earlier, it may occur degradation on fiber when the

treatment temperature is too high. During BMIMCL treatment, the temperature increases

more than 90 °C a few times. In heating process, stabilization of temperature is very

important. The structural may affected thus the mechanical properties will change too.

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Next, the magnetic stirrer was stuck a few times during the stirring process. It

takes a long time for the process which is 24 hours, magnetic stirrer is an alternative way

to stir it constantly and well mixed. It occurs because of the sawdust contain that made it

stuck during the process. To avoid from happen, using glass rod or spatula and manually

stir it. The treatment with BMIMCL which takes 24 hours cannot be done because the

laboratory lab only can use 8 hours a day. Therefore, it takes 4 days to complete the

treatment process. The treatment can be more effective when the treatment occurs straight

in 24 hours. Lastly, physical properties may study using water absorption test to prove

the relation between interfacial adhesion fiber with matrix and porosity occurred on the

surface.

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APPENDIX A

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APPENDIX B

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APPENDIX C

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APPENDIX D

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APPENDIX E

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