CONTENTS ACKNOWLEDGEMENTI CONTENTSII LIST OF FIGUREV LIST OF TABLEIX ABSTRACTX CHAPTER I INTRODUCTION 1 CHAPTER II LITERATURE OVERVIEW 5 2.1 RAFT Agent polymerization5 2.2 Synthesis of RAFT agent as a chain transfer agent (CTA) an example10 2.3 Synthesis of Silica nanoparticles11 2.4 RAFT Agent grafted onto silica19 CHAPTER III EXPERIMENTAL 23 3.1 Materials23 3.2 Instrumentation27 3.3Procedure of Experiment29 3.3.1Synthesis of BSPA29 3.3.2Procedure preparing colloidal silica30 3.3.3Activated of silica gel30 3.3.4Benzyl chloride functionalized silica (Si-Cl)31 3.3.5Synthesis of Si-BSPA31 3.3.6Synthesis of Si-BSPA32 3.3.7Aminolysis to cleave the grafted polymeric chain33 3.4 Procedure of Instrument34 3.41 Fourier Transform Infrared Spectroscopy (FTIR)34 3.4.2Nuclear Magnetic Resonance Spectrometer (1H and 13C NMR)35 3.4.3Differential Scanning Calorimeter, DSC35 3.4.4Thermal Analyzer TGA35 3.4.5Transmission Electron Microscope, TEM35 3.4.6Gel Permeation Chromatography, GPC36 CHAPTER IV RESULT AND DISCUSSION 37 4.1 RAFT Agent37 4.1.1 Synthesis of 3-(benzylsulfanylthiocarbonylsufanyl) propionic acid (BSPA)37 4.1.1.1 DSC measurement for BSPA37 4.1.1.2 FTIR anslysis of BSPA39 4.1.1.3 NMR analysis of BSPA41 4.2 Silica nanoparticles44 4.2.1 Activated silica gel44 4.2.1.1 FTIR spectra for silica gel, activated silica gel and colloidal silica44 4.2.1.2 TGA for silica active and colloidal silica47 4.2.2 TEM image of colloidal silica nanoparticles 4.2.3 Size determination by DLS of colloidal silica nanoparticle49 52 4.3 Benzyl chloride functionalized silica (Si-Cl)55 4.4 Silica grafted BSPA (Si-BSPA)59 4.5 Silica supported-poly(methyl acrylate) (Si-PMA) 68 CHAPTER V CONCLUSION 79 CHAPTER VI FUTURE WORK80 REFERENCE81 LIST OF FIGURE Figure 1-1RAFT mechanism2 Figure 2-1Organic reagents5 Figure 2-2Mechanism for achieving living character7 Figure 2-3Mechanism of RAFT polymerization involves a reversible addition fragmentation (J and R are species that can initiate free-radical polymerization. Where they may be polymer chains (i.e.-[CH2CXY]n) or they may be derived from radicals formed the dithio compound (1) or initiator9 Figure 2-4Generic structure of RAFT Chain Transfer Agent10 Figure 2-5Scheme formation of BSPA12 Figure 3-1Molecular structure of 3-Mercaptopropionic Acid23 Figure 3-2Molecular structure of benzyl bromide23 Figure 3-3Molecular structure of Si-Cl25 Figure 3-4Molecular structure of BSPA25 Figure 3-5Preparation Methodology of BSPA29 Figure 3-6Reaction formation of silica active30 Figure 3-7Reaction formation of Benzyl chloride fungtionalized silica (Si-Cl)31 Figure 3-8Reaction formation of Si-BSPA31 Figure 3-9Reaction formation of Si-PMA32 Figure 3-10Reaction of aminolysis33 Figure 4-1Melting point of BSPA from DSC analysis38 Figure 4-2FTIR spectrum for BSPA40 Figure 4-31H NMR of BSPA42 Figure 4-4 13C NMR of BSPA43 Figure 4-5FTIR spectrum for silica gel, activated silica gel and colloidal silica46 Figure 4-6TGA curves for activated silica and colloidal silica48 Figure 4-7 Typical TEM image of as-prepared silica particles at 0.1 wt% concentration, prepared by a single-stage reaction50 Figure 4-8Typical TEM image of as-prepared silica particles at 0.05wt% concentration, prepared by a single-stage reaction51 Figure 4-9DLS analysis for the mean particle size of colloidal silica at 0.1 wt% concentration in H2O.53 Figure 4-10DLS analysis for the mean particle size of colloidal silica at 0.05 wt% concentration in H2O.54 Figure 4-11FTIR spectra for Si-Cl from the commercial 5-15 nm fumed silica gel and the selt-synthesized 20.5 nm colloidal silica nanoparticle56 Figure 4-12TGA of Si-Cl from commercial fumed silica gel and self-synthesized colloidal silica nanoparticle.58 Figure 4-13FTIR of Si-BSPA made from the commercial 5-15 nm fumed silica gel and the self-synthesized 20.5 nm colloidal silica nanoparticle60 Figure 4-14TGA for Si-BSPA from commercial 5-15 nm fumed silica gel and self-synthesized 20.5 nm colloidal silica nano particle62 Figure 4-15TGA curve of activated silica, Si-Cl, and Si-BSPA for commercial silica, where a heating program from 40 oC to 500 oC at 10 oC/min under nitrogen was employed66 Figure 4-16TGA curves of activated silica, Si-Cl, and Si-BSPA for self-syntesized 20.5 nm colloidal silica nanoparticle, where a heating pogram from 40 oC to 800oC at 10 oC/min under nitrogen was employed67 Figure 4-17GPC analysis for cleaved PMA chain from Si-PMA (with free BSPA and using commercial fumed silica) 70 Figure 4-18GPC analysis for cleaved PMA chain from Si-PMA (without free BSPA and using commercial fumed silica) 71 Figure 4-19GPC analysis for cleaved PMA chain from Si-PMA (with free BSPA and using self-synthesized silica nanoparticle 72 Figure 4-201H NMR spectrum for free PMA chain (with free BSPA after synthesis of Si-PMA, and using commercial fumed silica)73 Figure 4-211H NMR spectrum for free PMA chain (without free BSPA after synthesis of Si-PMA, and using commercial fumed silica)74 Figure 4-221H NMR spectrum for free PMA chain (with free BSPA after synthesis of Si-PMA, and using self-synthesized silica nanoparticle)75 Figure 4-23TGA analysis for Si-PMA from commercial silica and self-synthezed silica with free BSPA and without free BSPA synthezed silica with free BSPA and without free BSPA77 LIST OF TABLE Table 4-1 Peaks assignments in FTIR spectra of silica gel, activated silica and colloidal silica45 Table 4-2 Peaks assignments in FTIR spectra of Si-Cl55 Table 4-3 Peaks assignments in FTIR spectra of Si-BSPA61 Table 4-4 Polymerization results for RAFT graft polymerization silica supported-poly(methyl acrylate) (Si-PMA) 78