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)

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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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