Synthesis, Characterization, and Gas Permeation Properties

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General Introduction The synthesis of cellulose nitrate laid the foundations for the chemical derivatization of the inexhaustible natural polymer followed by the synthesis of first thermoplastic polymer called celluloid in 1870, marking a milestone in the history of polymer science that revolutionized our modern life style. 7,8 Since then there became an avalanche of man-made or regenerated cellulose fibers based on wood pulp rather than native cellulose fibers, for textiles and technical products. Rayon is the oldest regenerated cellulosic fiber having been in commercial production since 1880s in France, where it was originally developed as a cheap alternative to silk, followed by the viscose process, currently the most important large scale technical process in fiber production, 9 and finally by the Lyocell process, an industrial breakthrough opening new frontiers in the field of environment-friendly fiber technologies. 10,1a By far now, the ester and ether derivatives of cellulose (exemplified in Schemes 2 and 3) have been lauded as the trail-blazing candidates of cellulose Cell O CH2�CH 2�CN Cyanoethyl Cellulose Scheme 3. A Few Examples of Commercial Ethers NaOH, CN Cell O R R = CH3 Methyl Cellulose R = CH3�CH 2 Ethyl Cellulose HO OH NaOH, R O O HO NaOH, R�Cl Cell OH Cell O CH 2 �CH�O�CH 2 �CH�OH 5 O R R R = H Hydroxyethyl Cellulose R = CH 3 Hydroxypropyl Cellulose m n NaOH, ClCH 2COO - Na + Cell O CH2COO Carboxymethyl Cellulose -Na +
General Introduction chemistry offering the most distinct and momentous applications of commercial and technical significance. Cellulose esters have found a variety of applications as classical material-coatings and controlled-release systems while recent developments include enteric coatings, hydrophobic matrices, and semipermeable membranes for applications in pharmacy, agriculture, and cosmetics. Furthermore, to serve the quest for high-performance materials based on renewable resources, cellulose esters are being widely employed as binders, fillers, and laminate layers in composites and laminates, as excellent material for photographic films, and as membrane-forming materials serving for gas separation, water purification, food and beverage processing, medicinal and bioscientific applications. 11 On the other hand, cellulose ethers on account of good solubility, high chemical resistance, and non-toxic nature are being utilized in drilling technology and building materials, as additives for drilling fluids to provide consistency control and to control the rheology and processing of plaster systems, and function as stabilizers in food, and constitute the principle ingredients of pharmaceutical and cosmetics formulations as well. 12 Recently, there has been an intense interest to exploit the biocompatibility, biodegradability, and chirality of naturally occurring renewable sources of polymeric materials. The past few years have witnessed an extensive research activity to elucidate the new ways of synthesis and to unveil the unique properties of cellulose-based materials expected to find a myriad of applications as liquid crystalline materials, 13 as biomaterials, 14 in enantioselective separation, 15 as composites with synthetic as well as biopolymers, 16 for the immobilization of proteins, 17 antibodies, 18 and heparin, 19 as adsorbents for the extracorporeal blood purification, 20 and in medicines and cosmetics. 21 Membranes for Gas Separation Membrane separation technology has emerged into a new era of advanced functional materials owing to its exquisite separation principle of selective transport and unique features of isothermal operation, facile integration, and low energy 6
Page 1 and 2: Synthesis, Characterization, and Ga
Page 3 and 4: Table of Contents General Introduct
Page 5 and 6: General Introduction cellulose deri
Page 7: General Introduction biogenetically
Page 11 and 12: General Introduction solution-diffu
Page 13 and 14: General Introduction A simplified t
Page 15 and 16: General Introduction been observed
Page 17 and 18: polymers. 41,46 General Introductio
Page 19 and 20: General Introduction Keeping in vie
Page 21 and 22: General Introduction the derivatize
Page 23 and 24: General Introduction strategy (G1-a
Page 25 and 26: General Introduction In conclusion,
Page 27 and 28: General Introduction 5. (a) Kobayas
Page 29 and 30: General Introduction 15. (a) Goetma
Page 31 and 32: General Introduction American Chemi
Page 33 and 34: General Introduction Macromolecules
Page 35 and 36: Silylation of Ethyl Cellulose Intro
Page 37 and 38: Silylation of Ethyl Cellulose milli
Page 39 and 40: Silylation of Ethyl Cellulose chlor
Page 41 and 42: Silylation of Ethyl Cellulose Resul
Page 43 and 44: Silylation of Ethyl Cellulose Solub
Page 45 and 46: Silylation of Ethyl Cellulose 1.034
Page 47 and 48: Silylation of Ethyl Cellulose poly(
Page 49 and 50: Silylation of Ethyl Cellulose the r
Page 51 and 52: Silylation of Ethyl Cellulose D.; Y
Page 53 and 54: Chapter 2 51 Chapter 2 Synthesis, C
Page 55 and 56: 53 Chapter 2 are few and far betwee
Page 57 and 58: 55 Chapter 2 constant volume/variab
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57 Chapter 2 Membrane Density. Memb
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59 Chapter 2 IR spectrum of 1 (Figu
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61 Chapter 2 1,3-bis(trifluoromethy
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63 Chapter 2 The increase in the po
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65 Chapter 2 other fluorinated poly
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67 Chapter 2 of the gas permeabilit
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69 Chapter 2 Gas Diffusivity and So
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71 Chapter 2 mobility of the perflu
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73 Chapter 2 1325-1329. (b) Hamza,
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Chapter 3 75 Chapter 3 Synthesis an
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77 Chapter 3 cost, and above all ap
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79 Chapter 3 molecular weights (Mn
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81 Chapter 3 1.99-2.07 (m, 2H, (CH3
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83 Chapter 3 25 °C, ppm): 11.9, 13
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85 Chapter 3 38.1, 44.7, 46.8, 47.9
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87 Chapter 3 CH2CH2C(=O)O), 2.50-4.
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89 Chapter 3 1091, 1053, 853, 806,
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91 Chapter 3 dendrons (G1-a-ІІ-G1
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93 Chapter 3 (DMAP) as a base, as s
Page 97 and 98:
Figure 3. FTIR spectra of 1, 2c, an
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97 Chapter 3 (partly soluble) and 3
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99 Chapter 3 increased polarity of
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101 Chapter 3 that of 1, and approx
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103 Chapter 3 derivatization per th
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105 Chapter 3 (2a-c) were in the or
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107 Chapter 3 2709-2719. (b) Schenn
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109 Chapter 3 17. van Krevelen, D.
Page 113 and 114:
Chapter 4 111 Chapter 4 Synthesis,
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113 Chapter 4 Since, no significant
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115 Chapter 4 Materials. Ethyl cell
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DStotal = DSEt + DSCarb (for 1a and
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119 Chapter 4 Figure 2. 1 H NMR spe
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121 Chapter 4 ruling out the possib
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123 Chapter 4 t-butyl moiety. A str
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125 Chapter 4 reported to lead to t
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127 Chapter 4 Table 4. Gas Permeabi
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129 Chapter 4 augmentation in eithe
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131 Chapter 4 indicate the signific
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133 Chapter 4 M.-R. J. Appl. Polym.
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Chapter 5 135 Chapter5 Synthesis an
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137 Chapter5 acid- and peptide-cont
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139 Chapter5 Specific rotations ([
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141 Chapter5 1.66 (brs, 1.1H, NHCH(
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143 Chapter5 as shown in Scheme 1,
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145 Chapter5 in Table 1. The molecu
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147 Chapter5 almost same pattern of
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Conclusions Table 3. Thermal Proper
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151 Chapter5 W.; Jing, X. J. Polym.
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Chapter 5 Synthesis and Properties
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Acknowledgments While submitting th
Page 159:
Synthesis, Characterization, and Ga
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Synthesis, Characterization, and Gas Permeation Properties

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