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the tube was exposed to air to terminate the polymerization. The collected eluents were concentrated and precipitated into an excess of hexane. Monomer conversions were observed by 1 H NMR based on integration areas. At resonance peak 4.0 ppm was considered as NIPA monomer and PNIPA, the integration factor was assented to 1 and the resonance peak 6.0-6.4 ppm (vinyl portion of NIPA) as monomer. By GPC analysis number average molecular weight, Mn and molecular weight distribution, Mw/Mn, were obtained. Thickness of the grafted membrane were measured by a multimode, Nanoscope IIIa controller (Digital Instruments, Santa Barbara, CA) equipped with an atomic head of 100×100 μm 2 scan range. Measurements were done in the air by contact mode using a commercially manufactured V-shaped silicon nitride (Si3N4) cantilever with gold on the back for laser beam reflection (Nanopics 2100, NPX2100). Air bubble contact angle measurements were made with a Data Physics telescopic goniometer with a Hamilton syringe with a flat-tipped needle. Water was used as the probe liquid. 2.3. RESULT AND DISCUSSION. ATRP of NIPA on the silicon surface was accomplished in presence of a free initiator, CuCl/Me6TREN system, and DMSO as a solvent, because the polymerization without the free initiator will give free polymers with Mn values independent of monomer conversion and high molecular weight distribution (Mw/Mn > 3). During the polymerization without a free initiator, the concentration of the Cu II complex produced from the reaction at the substrate surface is too low to reversibly deactivate P . , which is the propagating radical produced by the halogen atom (X) transfer from P-X to Cu I complex, with a sufficiently high rate. Thus, during polymerization reaction a minimum amount of deactivator is required to control the surface initiator of ATRP. On the other hand, the additional initiator would increase and adjust the concentration of Cu II complex as in a free ATRP system. Alternatively, the adjustment of the Cu II concentration could be made by directly adding an appropriate amount of Cu II complex. Another advantage of the addition of the free initiator is that it produces free polymers, which can be used for the measurement of molecular weight and molecular weight distribution of the graft chains, because the graft chains have nearly the same molecular weight and molecular weight distribution as the 34
Figure 2-7: (a) First order kinetic plot for ATRP of NIPA in DMSO at 20°C. (b) Monomer conversion vs time curve for ATRP of NIPA in DMSO at 20°C. (c) Dependence of molecular weight and polydispersity on conversion. 35
Page 1 and 2: Facile Approach to Synthesize Stimu
Page 3 and 4: Acknowlwdgement This dissertation w
Page 5 and 6: Chapter 1. Table of Contents 1-1. I
Page 7 and 8: 4.2.2.4.General Procedure for Synth
Page 9 and 10: Chapter 1 General Introduction 9
Page 11 and 12: The growth in industrial applicatio
Page 13 and 14: 1.3. Grafting methods. Most of thes
Page 15 and 16: 1.5. Components of ATRP. There are
Page 17 and 18: Figure 1-4:Mechanism of the Atomic
Page 19 and 20: near that of the human body, PNIPAm
Page 21 and 22: References and notes. 1. Plastiquar
Page 23 and 24: Chapter 2 Characteristics of High-D
Page 25 and 26: 2.1. INTRODUCTION. Atom transfer ra
Page 27 and 28: . Cl Si H + OH 9 + 10-undecen-1-ol
Page 29 and 30: Figure 2-3 (b): NMR spectrum of Pro
Page 31 and 32: Figure 2-4: Schematic procedure for
Page 33: 3000 2000 Wavenumber/cm -1 1000 Fig
Page 37 and 38: free polymers. We performed polymer
Page 39 and 40: Figure 2-9: Contact angles of air b
Page 41 and 42: 2.4. CONCLUSION. A detailed explana
Page 43 and 44: Chapter 3 Dominant influence of the
Page 45 and 46: 3.1. Introduction. Temperature resp
Page 47 and 48: and FT-IR analyses, were used as re
Page 49 and 50: azide Figure 3-2: FT-IR spectra of
Page 51 and 52: Figure 3-3: 1 H NMR spectrum of aci
Page 53 and 54: 3.3. Results and discussion. ATRP t
Page 55 and 56: temperature. 28 Electro-negativity
Page 57 and 58: Contact Angle (degree) 141 138 135
Page 59 and 60: Figure 3-7 shows equilibrium contac
Page 61 and 62: References and Notes. (1) S.A. Prok
Page 63 and 64: Chapter 4 Precise Synthesis and Phy
Page 65 and 66: 4.1. Introduction. Stimuli-sensitiv
Page 67 and 68: 4.2. Experimental Section. 4.2.1. M
Page 69 and 70: hr and at room temperature for 12 h
Page 71 and 72: chromatography with hexane/ethyl ac
Page 73 and 74: 4.2.2.4.General Procedure for Synth
Page 75 and 76: Figure 4-4. Schematic illustration
Page 77 and 78: Figure 4-5. FT-IR spectra of dried
Page 79 and 80: are necessary to achieve maximum bo
Page 81 and 82: Figure 4-1-1: XPS data of (a) C 1S
Page 83 and 84: The successful deposition of CPU-dM
Page 85 and 86:
where f i is the area fraction of c
Page 87 and 88:
The ATRP in this condition provides
Page 89 and 90:
Figure 4-1-5: AFM image of densely
Page 91 and 92:
Figure 4-1-8. Graft density of PNIP
Page 93 and 94:
Figure 4-1-7. Plots of Ld/Lc,w vers
Page 95 and 96:
Figure 4-1-9. Thickness of high den
Page 97 and 98:
Figure 4-7. a) FT-IR spectra and b)
Page 99 and 100:
Figure 4-1-10 (c): Area ratio for t
Page 101 and 102:
Area ratio 0.4 0.35 0.3 0.25 0.2 0.
Page 103 and 104:
(a) Figure 4-1-11 . Contact angle o
Page 105 and 106:
(c) Figure 4-1-11. Contact angle of
Page 107 and 108:
The temperature dependence for the
Page 109 and 110:
4.4 Conclusions. High-density therm
Page 111 and 112:
(16) Osada, Y.; Gong, J. P. Prog. P
Page 113 and 114:
2006, 22 (9), 4259-4266. L Macromol
Page 115 and 116:
(76) The Young equation, cos θ = (
Page 117 and 118:
Abstract. High-density polymer brus
Page 119 and 120:
previously grafted chain prevents l
Page 121 and 122:
5.3.1. Synthesis procedure of the A
Page 123 and 124:
5.4.1. Fourier Transform Infrared S
Page 125 and 126:
5.5. Result and discussion. Scheme
Page 127 and 128:
graft density (chain/nm 2 ) 0.8 0.6
Page 129 and 130:
Thickness (nm) 50 40 30 20 10 0 0 1
Page 131 and 132:
a nm 1μm b nm 1μm Figure 5-5. The
Page 133 and 134:
5.6. Conclusion. ATRP of PNIPA in D
Page 135 and 136:
(17) Huang, E.; Rockford, L.; Russe
Page 137:
Publications. 1. Suzuki H., Huda M.
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