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CHARACTERIZATION OF PLA-BASED NANOCOMPOSITES IN BIOMEDICAL APPLICATIONS
Yong Hui Sun
Bachelor of Engineering with Honours (Chemical Engineering)
2015
U 'IVERSITl MALAYSlA SARAWAK
Grade:
Please tick (,f ) final Year Project Report Masters §PhD
DECLARATlON OF ORIGINAL WORK
Thi s declaration is made on the}I ~~.(taY.QrMy..~.9. !'~.
Student 's Declaration :
I, YONG HUI SUN (33544), DEPT. OF CHEM ICAL ENGINEERING AND ENERGY
SUSTAINAB ILlTY, fACULTY Of ENG INEERING hereby declare that the work entitl ed,
"SYNTHESIS AND CHARACTER IZATION OF PLA-BASED NA NOCOMPOS ITES IN
BIOMEDICAL APPLICATIONS" is my original work. I have not copied from any other students '
work or from any other sources except where due reference o r acknowledgement is made expli cit ly in
the text, nor has any part been written for me by another person.
3 1"JULY20 15 it$~-Date Submitted YONG HUISUN (33544)
Final Year Project's Declaration:
I, MD REZAUR RAHMAN hereby certifies that the work enti tled , ··CHARACTER IZATION OF
PLA -BASED NANOCOMPOSITES IN BIOMEDICAL APPLI CATIONS" was prepared by the
above named student, and was submitted to the " FACULTY" as a • pal1iall full fulfilment for the
conferment of BACHELOR Of ENGINEER ING WITH HONOURS (CHEM ICAL
ENGINEERING), and the aforemen tioned work, to the best of my knowledge, is the sa id student 's
work
Received for examination by: ~ Date: ~/~-(DR. MD REZAUR RAHMAN)
. -.-------1-
I declare that this ProjectlThesis is classified as (Please tick ("l):
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o 1972)*
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GJ OPEN ACCESS
Validatioo of Report
I there fo re dtlly affirmed wi th free conse nt and wi llingness declared that th is said ProjectlThesis shall be placed officia lly in Depanment of Chem ical Enginee ring and Energy Sustainabi lity with the abide interes t and ri ghts as fo llows:
• Thi s Repon is the sa le legal property of Depanment of Chem ical Engi neering and
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Report once it becomes sa le property of Department o f Chemica l Enginee ring and
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• This Report or any materia l, data a nd information rela ted to it sha ll not be distr ibuted,
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Enginee ring and Energy Sustainability, Uni vers iti Malays ia Sarawak (UN /MAS)
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Student' s signature: ~-$:t Supervisor's signature: -----0------ '01"Ju ly 20 15) (3 1" July 20 15)
Current Address: I I, JA LAN 12, TAMAN DELIMA, 86000 KL UANG, JOHOR.
Notes: * If the Project/Thes is is CONFIDENTIAL or RESTRICTED, please a ttach together as annex ure a letter from the organisation with the period and reasons of confidential ity and restri ction.
APPROVAL SHEET
This final year thesis report which enti tled "CHARACTERIZATION OF PLA
BASED NANOCOMPOSITES IN BIOMEDICAL APPLICATIONS" was
prepared by Yong Hui Sun (33544) is hereby read and approved by:
31" July 2015 DR.lVlD REZAUR RAHlVlA (Date)(Final year Project Supervisor)
':':.!.t lGil""., i\takiuq./ .... ,ndfmlt v ....'ERSm MALAVSIA SARAWAJ(
CHARACTERlZATION OF PLA-BASED NANOCOMPOSITES IN BIOMEDlCAL APPLICATIONS
YONG HUI SUN
Dissettation submitted in partial fulfilment of the requirement
For the Degree of
Bachelor of Engineering with Honours
(Chemical Engineering)
Faculty of Engineeri ng Uni versi ti Ma laysia Sarawak
20 15
-~--•. .-------
Dedicated to my be loved parents and family, who a lways bestow me with full suppo,1s and encouragement
ACKNOWLEDGEMENT
The author wishes to ex press most sincere appreciati on and deepest grati tude to
all individuals, pa rti es and organizati ons that have contri buted and cooperated
throughout thi s fina l year thes is report. Spec ial thanks are dedi cated to the superv iso r,
Dr. Md Rezaur Rahm an for hi s unwavering who lehearted patience and invaluabl e
supervis ion towards the completion of this repo rt. Not fo rgettin g the laboratory
technic ians from Departm ent o f Chemica l Engineering and Energy Susta inabil ity and
Department of Mechanica l and Ma nufacturing Engineerin g for thei r willingness to share
va luable knowledge and experiences as we ll as the hard wo rk and dedicat ion throughout
the author's research. Last bu t not least, the author wou ld like express her apprec iat ions
towards he r beloved fam il y, course mates, lecture rs, and fr iends for their endless
supports, co-operati ons, and motivations in completin g thi s report.
ABSTRACT
The research aims to stud y th e enhancement and improvement in the propelties of PLA
based nanocomposites by adding different nanofill ers at different we ight percentages.
Biodegradable pol ymers co uld be the most promising alternatives for replacing
conventional petroleum-based po lymers. Poly (lactic acid) can be derived from
renewable reso urces and many researches had been carried out for the PLA-based
nanocomposites. PLA-based nanocompos ites is widely used in man y applications such
as biomedi cal applications. Nanocomposites used in biomedical applications requires
specific requirements and limitations in pure PLA matri x such as lower thermal
resistance and poo r mechanical properties which can be enhanced by the incorpo ration
of nanofillers such as nanoc lays and fumed sili ca. Four diffe rent types of nanoc lays
were used in this study whi ch were Nanomer® 1.28E, Nanomer® 1.30£, Nanomer®
1.31 PS and Nanomer® 1.34TCN . Fumed silica was used for the preparation of
nanocompos ites. The nanocompos ites were prepared in different weight percentages of
nanofillers by solvent casting method . The addition of nanofilJ ers showed improvement
in properties and characteristics of the PLA-based nanocompos ites. The morphological
study, mechanical properties, FTlR anal ys is, and BET surface area anal ysis were carried
out and the results showed that the PLAt fumed silica with 1.25wt% silica content was
the best reinforc ing agent with the largest surface area with. The mechanical properties
of PLA-based nanocomposites showed that Nanomer® 1.3 1 PS exhibited higher tensile
strength and Young 's modulu s du e to the strong dispersion and interaction between
PLA matrix and nanocJays. The SEM analysis showed that Nanomer® J. 3 J PS acted as
compatibilizer for reinforcing the interfaci a l action and miscibility between two phases .
Potentia l interacti on of PLA matri x and nanofillers was studi ed by FTIR anal ys is.
PLA-based nanocompos ites have promising potential that can be developed as future
material in 2 1 Sl century.
Keywords Biodegradable polymer; Pol y (Lactic acid) ; Nanocomposites;
Nanofillers; Nanoc lays ; Fumed Silica
II
ABSTRAK
Kajian ini bertujuan untuk mengkaji penambahbaikan dan peningkatan dalam sifat-sifat
nanokomposit berbasis PLA dengan penambahan "nanolillers" yang berbeza mengikut
peratusan berat yang berlainan. Polimer biodegradable boleh menjadi alternatif yang
paling menjanjikan untuk menggantikan polimer konvensional yang berasaskan
petroleum.Poli (laktik asid) dapat diperolehi daripada sumber yang boleh diperb aharui
dan banyak kajian telah dijalankan bagi nanokomposit berbasis PLA. Nanokomposit
berbasis PLA telah digunakan secara meluas dalam pelbagai apli kasi seperti aplikasi
bioperubatan. Nanokomposit yang di gu nakan dalam aplikasi bioperubatan memerlu ka n
syarat-syarat tertentu dan kekurangan dalam matrik PLA yang tulen seperti rintangan
haba yang rendah dan sifat mekanikal yang tidak memuaskan boleh dipeliingkatkan
dengan penggabungan "nanolillers" seperti "nanoclays" dan silika fumed Ice dalam
polimer matrik. Empat jeni s "nanoclays" iaitu Nanomer ® 1.28E,Nanomer ® Nanomer
® 1.30E, Na nomer ® 1.3 1PS dan Nanomer ® 1.34TCN telah digunakan dalam kajian.
Silika fumed telah digunakan untuk penyediaan nanokomposit. Nanokoll1posit telah
di sediakan dengan peratusan beral yang berlainan mengikut "nanofillers" melalui
kaedah "solvent casting". Penambahan "nanofi ll ers" menunjukkan penambahbaikan
dalam sifat and ciri nanokomposit berbasis PLA. Kajian morfologi , sifat Illechallikal,
anal isis FTIR, dan allali sis permukaan BET teleh dijalankan dan hasil telah
menunjukkan PLA/s ilika fumed nanokomposit dengan 1.25 wt % of kalldungan sil ika
merupakan agent pengukuh ya ng lebih baik dengan kawasan permukaan yang paling
luas. Sifat mekanikal untuk nanokoillposit menunjukkan Nanomer® 1.31 PS memberi
kekuatan tarik dan Modulus Young yang tinggi disebabkan penyebaran yang kuat dan
interaksi antara PLA matrik dan ""nanoclays'·. Analisis SEM menunjukkan Nanomer®
1.3 1PS benindak sebagai untuk mengukuhkan tindakan antara permukaan dan kelarutan
campu ran antara dua fasa. Potensi interaksi bagi matrik PLA dongan " nano lillers" telah
dikaj i dengan analisi s FTIR. Nanoko mposit berbasis PLA mempunya i potensi yang
menjanjikan untuk membangun sebagai bahan ma sa depan dalam abad ke-21.
Keywords Po limer biodegradable; Poly (Lakt ik as id); Nanokompos it ;
"NanoliUers"; "Nanoc1 ays"; Sili ka Fumed
III
TABLE OF CONTENTS
Page
Acknow ledgement
Abstract II
Abstrak iii
Table of Contents iv
List ofTabJes Vil
List of Figu res V III
List of Nomenclatures XI
List of Abbreviations XI II
CHAPTER 1 RESEARCH INTRODUCTION
1. I Background of Study
1.2 Pmblem Statement of Research 3
1.3 Research Objectives 4
1.4 Scope of Study 4
1.5 Expected Outcomes of Research 5
1.6 Summary 5
CHAPTER 2 RESEARCH LITERATURE REVIEW
2. 1 Overv iew 6
2.2 Biodegradable Polymers/ Biopo lymers 6
2.2.1 Sources of Biodegradable Polymers 8
2.2.2 Poly (lactic acid) (PLA) 9
2.3 Nanocompos ites 12
2.3. I Bionanocompos ites/ Nano-biocomposites 14
2.3.2 Techniques/ Routes for Biodegradable 16
Polymer Nanocomposites
2.4 Nanofi l le rs/ Nanoreinfo rcements 18
2.4. 1 Nanoclays/ Layered Silicate 20
2.4.2 Fumed Si lica (Nano-Si0 2) 23
2.4.3 Po lymer/ NanocJays . anocomposites 25
IV
(Layered S ili cate-Based Nanocompos ites) 2.4.4 Polymerl Fumed Silica Nanocompos ites 28
2.5 Lim itations of PLA matrix and Its Properti es 31
2.5. 1 P LAlNanociays Nanocompos ites 33 (PLA/ Layered Silicate Nanocompos ites)
2.5.2 PLAI Fu med S ilica Nanocompos ites 37 2.6 Adva ntages of PLA and Its Na nocompos ites 39 2.7 Applications ofPLA and It s Nanocom posites 41
2.7. 1 B iomedical App licati ons 43 2.8 Outlooks of Nanotechno logy and App lications 46
of PLA -Based Nanocomposites 2.9 Summary 48
CHAPTER 3 RES EA RCH METHODOLOGY
3.1 Overview 49 3.2 Resea rch Flowchart 49
3.3 Va riab les of Resea rch 50 3.4 Material s, Equipm ent, and Instrum ents 51
3.4.1 Materia ls 51
3.4.2 Equi pment and Instruments 52
3.5 Nanocomposites Preparation 52 3.6 Characte rizations 53
3.6.1 Mechani ca l Properti es (Tens il e Testing) 53
3.6.2 Chem ical Structura l Ana lysis (FT IR) 54 3.6.3 Mo rphological Stud y (SEM) 54
3.6.4 Surface Area In vesti gati on (BET) 54
3.7 Summary 55 CHAPTER 4 RESULTS AND DISCUSSION
4.1 Overv iew 56 4.2 Mechan ica l P roperties (Tensi le Testing) 56 4.3 Chemica l Structural Anal ys is (FTIR) 64 4.4 Morpho logical Study (SEM) 71
4.5 Surface Area In vest igation (BET) 72
4.6 S ummary 76
v
CHAPTER 5 CONCLUSION AND RECOMMENDATIONS 5. J Overvi ew 77
5.2 Conclusion 77
5.3 Recommendations for future Works 78
BIBLIOGRAPHY 79
APPENDIX A IR SPECTRA TABLE 92
APPENDIX B RESULTS 94
APPENDIX C CALCULATIONS J J I
APPENDIX D RISK ASSESSMENT I J 6
V I
LIST OF TABLES
Table Page
2.1 Physical properties of PLA. " 2.2 Types o f nanocompos ites and its examples . 12
2.3 Natura l and synthetic biodegradabl e matrices . 15
2.4 Chemica l structure of commo nly used 2: I ph yli os il icates. 20
2.5 Organi c modifi ed laye red s ili cates . 22
2.6 Specific characteristic o f different kinds of fumed sili ca. 24
3. 1 Types of nanoclays used in the research. 51
3.2 Samples prepared w ith different weigh ratio. 52
Summary o f mechani ca l propert ies for PLA/Nanociays 4 .1 63
nanocomposites
4 .2 Summary o f BET surface a rea ana lysi s. 75
-'" V II
,--------------
4.3
4.4
4.5
4.6
4.7
4.8
4.9
4. 10
4. 11
4. 12
4 .1 3
4.14
4.15
4.16 (a)
4.16 (b)
4.16(c)
4.16(d)
4.17
4. 18
Tens il e strength of PLAI Nanomer® J.30£ nanocomposites.
Young' s modulus of PLAI Nanomer® 1.30£ nanocomposites.
58
58
Te nsile strength of PLAI Nanomer® 1.31 PS nanocompos ites. 58
59Young's modulus of PLAI Nanomer® 1.30£ nanocompos ites.
Tensi le strength ofPLAI Nanomer® 1.34TCN nanocomposites. 59
Young 's mod ulus of PLAI anomer® 1.34TCN 60
nanocomposites.
Tensile stre ngth of PLA/ Fumed Silica nanocomposites at 60
different we ight percentage.
Young's modulus o f PLA/Fumed Silica nan ocom posites at 61
different weight percentage.
IR spectra of PLAI Nanomer ® 1.28£ (4.17wt %. nanoel ays). 66
IR spectra of PLAI Nanomer ® 1.30£ ( 12.50wt %. nanoelays). 67
IR spect ra ofPLAI Nanomer ® 1.3 1 PS (12.50"'1 %. nanoclays). 68
lR spectra of PLAI Nanomer ® 1.34TCN (12.50wt %. 69
nanoelays).
IR spectra ofPLAI Fumed S il ica ( 1.25wt %. fumed s ilica). 70
Scanning e lectron m icrographs of PLA+ 0.5g Nanomer® 1.28£ 7 1
Scanning e lectron micrographs of PLA+ 1.5g Nanomer® 1.30E 7 1
Scanning e lectron micrographs of PLA+ 1.5g Nanomer® 1.3 1 PS 7 1
Scann ing electron m icrographs of ) PLA + 1.5g Nanomer® 71
134TC
Scann in g electron micrographs of PLA/O. I 5g fumed s i Iica 72
nanocomposites.
B£T plot for PLA+ 0.5g Nanomer® 1.28£. 73
LX
4. 19 BET plot for PLA+ I .5g Nanome r® 1.30E. 73
4.20 BET plot for PLA+ I .5g Na nomer® 1.3 JPS. 74
4.2 1 BET plot for PLA+ 1.5g Nanomer® 1.34TCN. 74
4.22 BET plot fo r PLAID. I 5g fum ed sili ca nanocompos ites. 75
4.23 Comparison for Sy for selected samples. 75
x
LIST OF NOMENCLATURES
dynes Iamicronewtol1S
degree celsius
fmol/msPa femtomole per meter per second per pascal
g gram
gi la min gram per I aminu tes
gram per cubic centimetre
" I ~ I gram per li tre<>
GPa g iga pascal
Jig j oul es pe r g ram
Ji m joul es per mete r
11mI joules per millili tre
K kelv in
kN kil o newton
kilogram per cubic meter
kgl mo l kilogram per mo le
m% mass percent so lutions
MPa mega pascal
flm micrometre
nm nanometer
per centimetre
% percentage
mor l per mole
XI
m2/g sq uare meter per gram
m 2 / mo l square meter per mo l
TS tensi Ie strength
US$ US doll ar
wt% we ight percentage
Ey Young's modulus
XII
_If" 1____________
LIST OF ABBREVIATIONS
A I20)
SET
CO2
CNT
CEC
CPN
OSC
OMTA
EG
FTIR
GRAS
HOPE
-OH
HA
PHV
ISSM
LOH
-CH,
MMT
NF-MS
OMA
NMR
alumina
bru nauer-em mett-telle r
carbon diox ide
carbon nan otubes
cation ic exchange capac ity
c lay/polyme r nanocomposites
differenti al scannin g ca lo rimetry
dynami c-mechani ca l therm al ana lys is
expanded graphite
fo uri er transfo rm infra red spec trosco py
generally recognized as safe
high-density polyelhy/ene
hydrox ide group
hydroxyl-apatite
hydroxy l-valerate
injection stretch blow molded
lactate dehydrogenase
methyl group
montmorillo n ite
nanofibrous microspehres
n, n' -dimethyacetamide
nucl ear magnetic resonance
Xill
I\.. ~-
OMLS organicall y modified layered s ilicate
OMMT organo-modified montmorill onite
phr parts per hundred pa rts o f res i n
PHB poly- 3- hydroxy butyrate
PA6 po lyamide 6
PBS po lybutylene succ inate
PBSA poly (buty lene succ inate-co-adipate)
PCL po lycaprolactone
PC polycarbonates
LLDPE po lyeth ylene
PE polyethylene
PEG pol yeth ylene glyco l
PGA polygl yco lic ac id
PHA po lyhydroxyalk anoales
PLA poly(lactic ac id)
PLGA poly(lactic-co-glycolic acid)
PMMA poly (methyl methacrylate)
PNIPAM po ly(n-isopropylacry lamide)
PPS polyphenylene sulfide
PP po lypropy lene
TPO po lypropylene-elastomer
PS po lystyrene
PT polythiophenes
PVA po ly (vinyl) a lcoho l
PVC pol y (v iny l chloride)
X IV
CHAPTER 1
RESEARCH INTRODUCTION
1.1 Background of Study
Na notechnology has been di scussed and many researches have been done by
scientists, engineers and researchers. It has become one of the prominent fields in all
technica l disciplines for tod ay's resea rches and developments. It can be defined as
"tec hnology at th e nanoscale" (Ra msden, 20 II ). Nanotechnology is a fi e ld of applied
sciences and technologies that invo lve the applications in nanoscale and understanding
about properties and phenomena of nanomate ri als and nanostructures. Due to the higher
demands from mankind in term of finer and better prod ucts, nanotechnology has been
introduced fo r the development of innovation for new adv anced materials. The coming
decades is estimated to be dominated by nanotechnology in which the practice of
iden tification of new ad vanced materials w ill be devi ated Thi s new advanced
technology req uires new materials with superi or phys ica l, chemical and mechanical
properties to meet the satisfacti on of consumers (Fu lekar, 20 j 0).
Nanostructured materials have been studi ed worldwide fo r the development of
new advanced material s with at least one dimension falling in nanoscale . One of the
applicat ions l'or thi s advanced material s is nanocompositcs (Wu et aI., 2015).
Na nostructures are the new materia ls and are modulated over the zero-dimens ional (00 ),
one-dimensional (10), two-dimensional (20), and three -d imensional (3~). A variety of
nanomateria ls have been developed and introduced based on these different ran ges of
dimension. There are three types of nanofi lle rs or nanoreinforccments and they a re
categorized based on their dimensions in po lymer matrices (Thomas, & Stephen, 20 10).
The categories of mmofillers are class ifi ed acco rding to their morph o logy, aspect rat io
and geometry such as layered which is clays, spherical which is silica and acicul ar
which are whiskers and carbon nanotubes (Bordes et aI., 2009). These nanofilJers
interacted with polymer matric to form polymer nanocomposite materials .
....a.~ ..............----------------
1.0 Research Introd uction
The decrease in the size of fillers into nanosca le had made the non-bonding interactions
between the nanoparti cle surface and polymer segmen t in which the vicin ity of particles
become stronger. The nanofi llers such as layered silicate clays, carbon nanotubes,
nanoftbers and sil ica nanopartic les that are added into po lymer matrix compos ites
greatl y enhanced and improved the properties of overall composite materials due to the
massive surface- to-vo lume ra tio of nano particles (Bhattacharya et aI., 2007). Nanoclays
or layered silicates and nanosilica are the most promi sing nanoullers that coul d enhance
the properties of nanocomposites. Many researches had been conducted for the
improvement in the properties of nanocomposites with the addition of nanoul lers
(Bhattacharya et aI. , 2007).
Nanocomposites are multiphase structure materia ls in which the dimensions fall in
nanometer ran ge in at least one of the phases (Anand han & Bandyopadhyay, 20 II ).
These high performed materia ls exhibit specia l combination s in properties and design
poss ibilities and cons idered as materia ls o f 21 st century. Three types of combination of
nanocom pos ites are avail ab le which includes iso-d imensional nanopa rticl es with th ree
nano dimensions, nanotubes or whiskers w ith two nano dimensions and po lymer
layered crysta l nanocomposites with one nano dimension (Jamsh idian et aI. , 20 10).
Nowadays, nanocomposites give innovative technology and opportun iti es in business
and being environmental-frie ndl y in the market for engineering po lymers and useful in
appl ications such as packag ing an d biomedical. The development of compostabl e and
biodegradable po lymers as new generation of polymers has rece ived much attenti ons
(Lai et a I. , 20 14). Thermoplastics, therm osets and elastomers are used in research on
making of po lymer nanoco mposites . Aliphatic polyesters are the most promis ing
biodegradable materia ls among the biodegradable polymers due to the characteri stics on
read ily susceptible to biologica l (Mo hapatra et a I. , 201 2). A combination of
nanomaterials with the polymer matrix have the inherited properties with high stren gth
and stiffness and improves the damage tolerance of nanocompos ite material s (Sahay et
aI., 20 14). The addition of nanofil lers to enh ance the properties of nanocompos ites had
been the topic o f researches recently. Fukushimet al. (2009) asserted that add ition of
nanosca le fil lers had great potential for being exce llent in properties to the polymer
nanocomposi tes. Joseph et al. (20 14) di scovered that macro , micro and nanofi lle rs were
added in PLA matrix system showed enhancement in mechanical, barrie r and thermal
prope rties.
2
1.0 Research Introducti on
Thus, in thi s research, the hi ghlight w ill be focused on the improvement and
enhancement of PLA matri x with the add ition of nanofillers including four different
types of nanoclays and fumed silica. Different weight percentages of nanocl ays and
fumed silica were add ed in PLA matrix to form nanocomposites. The performance of
nanocompos ites w ill be investigated using several methods and technique with
equipment avail able .
1.2 Problem Statement of Research
Waste disposal issue has urged the contributions of research in effort on the
development o f new advanced material s with the combinati on of en vironmenta l
susta in ability and biodegradabili ty or compostability. The biodegrad able polymers have
potenti al in solving thi s environmenta l iss ue brought by non-biodegradable po lymers.
However, the properties of the biodegradable polymers need to be improved and the
main limitations of biodegradable polymers in the applications are the poor thermal and
mechani cal resistance. Poly (l actic acid) (PLA) has ex isted fo r several decades and it is
considered as versatile polymer that made from renewable agri culture materia ls. Out of
all biodegradable polymers, PLA has pro perti es w ith good appearance, hi gh mechanical
strength , lo w toxicity and good barrier properties. The properties need to be improved
for PLA to optimize its ability in engineering and industria l applications sLich as
biomedi cal applications. Studies showed that the blending of PLA matri x with
nanofill ers could improve its properties and reduce cost. Various nanofill ers have been
considered as reinforcin g agents for PLA matri x in order to enhance and improve the
properties and provide additi onal functionalities to the polymers.
Thus thi s research focused on developing new nanomaterials based on PLA
pol ymer matri x . Biodegradable polymers such as PLA are especia lly as interest for
applications such as packag ing and biomedica l application (Hapuarachchi , & Peij s,
20 I 0) . However, the properties are the ma in constraints for the engineerin g applications
especia lly in biomedical applications. PLA has been used in biomedical applications
s lIch as surgical sutures, im plants and dru g delivery systems. Specia l attenti on for
advanced research in the properti es improvement o f PLA is essential. This research
aimed to study the o utcome oflhe interaction of po ly (lactic acid) matri x w ith nanoclays
and fumed silica at diffe rent weight percentages.
3
1.0 Research Introduction
Solvent casting method will be used in thi s research for the preparation of
nanocomposite sample and di ffe rent weight percentage or weight ratio of l1an ofi llers
wi ll be added in the PLA matric . Di ffe rent types of nanoc lays are used to invest igate the
best combination of nanocomposite materia ls. The o utcome of the stud y is justified by
the study of morph ology, mechanical properties, and structura l properties of the
nanocomposites.
1.3 Research Objectives
This research project was conducted an d carried out based o n speci fic objectives
which include:
a. To in vesti gate the morpho logy, mechanical , and structural properti es o f
poly (lacti c acid) based nanocompos ites .
b. To stud y the effect of different weight ratio of nanoclays and fumed s ilica
on the propelties of nanocomposites.
c. To compare the properties of nan oc lays-based nanocompos ites with the
fum ed -s i lica based nanocompos ites.
1.4 Scope of Study
The sco pe of the research proj ect foc used on the improvement in th e properties of
PLA-based nan ocomposites that suitab le in engineering applications such as biomedica l
applications. The potentia l biodegradable po lymer used to produce nanocompos ites in
thi s research is po ly (lactic acid) and the ad vantages of biodegradabl e po lymers in
vario us applications a lso will be di scussed. T he en hancemen ts of properties of
nanocompos ites are invest igated with suitabl e methodo logy. So lvent cast ing technique
is used fo r preparation of nanocomposites.
The mo rphology, mechani ca l, and structural properties are stu died by seve ral tests
and ana lysis. Different types ofnanoclays are used in this study to fll1 d out wh ich types
of nan oclay shows good performance when interacted with PLA matrix. A study on th e
combination of PLA matrix with fumed s ilica is also carried o ut to stud y the
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1.0 Research Introduction
perfo rmance of nanocom pos ites. T he results will be compared among the nanofillers
used and the perfo rmance of the nanocompos ites will be ana lyzed .
1.5 Expected Outcomes of Research
The adding of nan oc lays and fumed s ili ca in poly ( lactic ac id) matrix respectively
In prepa ration of biodegradable nanoco mposites will changed th e morphology,
mechanical propeliies, chemical structures and surface area of nan oco mpos ites.
Different weight percentage of the nan ofillers shows different characteri stics in PLA
based nanocompos ites. The differen t types of nanoelays a lso show different properties
in PLA/na noc lays nanocomposites . PLA/fum ed silica nanocomposites perform better
compared to PLAlNanoclays nanocomposites.
1.6 Summary
Thi s chapter discussed about the backgro und of the research project. The use o f
nanotec hnology had innovated new advance materials in nanoscale an d will be fu ture
techno logy for innovation. The properties of nanocompos ites with the use of PLA
matrix shou ld be enha nced in order to be applicable in many others precise applications
such as biomedical applicati ons. Thus, the addition of nanoti llers sLIc h as nanoc lays and
fumed s ili ca seem to be a potenti al so lut ion fo r the enh ancements . The potential
improvement on the properties of PLA based nanocompos ites is studied for thi s proj ect.
T herefore , the effect on the interaction of PLA matrix with nanoclays or fumed si lica in
di ffe rent we ight rati o will be carried out. The pro blems arisen and the objectives to
solve the pro blems are also di sc ussed in this chapter. T he research will be carried out
based on the prob lem statement, a im and objectives discussed. The nanocomposites will
be pre pared in thi s research and the properti es will be tested by several methods and
techniq ues.
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