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Methoxy Poly (Ethylene Glycol) Methacrylate - Based

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Methoxy Poly (Ethylene Glycol) Methacrylate - Based METHOXY POLY (ETHYLENE GLYCOL) METHACRYLATE - BASED COPOLYMERS ON THE APPLICATIONS OF CONCRETE ADMIXTURES, MESOPOROUS MATERIALS, AND RHEOLOGY MODIFIERS A Dissertation Presented to The Graduate Faculty of The University of Akron In Partial Fulfillment of the Requirements for the Degree Doctor of Philosophy Pattarasai Tangvijitsakul December, 2015 METHOXY POLY (ETHYLENE GLYCOL) METHACRYLATE - BASED COPOLYMERS ON THE APPLICATIONS OF CONCRETE ADMIXTURES, MESOPOROUS MATERIALS, AND RHEOLOGY MODIFIERS Pattarasai Tangvijitsakul Dissertation Approved: Accepted: Advisor Department Chair Dr. Mark D. Soucek Dr. Sadhan C. Jana Committee Chair Dean of the College Dr. Kevin Cavicchi Dr. Eric J. Amis Committee Member Interim Dean of the Graduate School Dr. Avraam I. Isayev Dr. Chand Midha Committee Member Date Dr. Li Jia Committee Member Dr. Chrys Wesdemiotis ii ABSTRACT Hydrophilic copolymers were prepared and used in different applications including dispersant additives for cement, thin film batteries, and thickener in water- borne latex coating respectively. The copolymers were prepared using methoxy [poly (ethylene glycol) methacrylate] or MPEGMA and methacrylic acid (MAA) by different polymerization techniques e.g. reversible addition-fragmentation chain transfer (RAFT) polymerization, conventional radical polymerization, and esterification process. Different ratios of monomers and different side chain lengths of MPEGMA were utilized in order to investigate those effects of the fluidity of fresh cement/concrete. The effect molecular weight, molecular weight distribution, and the copolymer structures on fluidity of fresh cement/concrete were also studied. In addition, it was found that a new RAFT polycarboxylate terpolymer (containing in-situ defoaming groups) not only able to provide a reasonable cement fluidity over a long period of time, but also able to control the amount of generated bubbles at the same time. This may probably lead to a new candidate admixture for an outdoor concrete structural application that requires freeze- thaw resistance without adding separate defoaming agents. iii A new series of amphiphilic block copolymers, poly (methoxy poly (ethylene glycol) methacrylate) - block - poly (butyl acrylate) [PMPEGMA – b – PBA] were successfully synthesized via RAFT polymerization and were characterized via Nuclear Magnetic Resonance (NMR) and Gel Permeation Chromatography (GPC). These block copolymers were then used as micelle templates for mesoporous mixed metal oxide materials between cobalt and/or nickel for thin film battery. A new fatty acid-based rheology modifier, poly [methoxy poly (ethylene glycol) methacrylate]-block–poly (oleic acid) [PMPEGMA–b–POA], was also synthesized by RAFT polymerization. The steady-shear properties of a well-characterized conventional latex, thickened with the different concentrations of the resulting fatty acid - based rheology modifier, were measured at constant pH and temperature. Shear thinning behavior in the latex solution with PMPEGMA homopolymer was observed. In addition, hydrophobically modified rheology modifier increased the thickening effect in the latex solution due to the transient intermolecular and intramolecular associations. iv ACKNOWLEDGMENTS I would like to express my sincere gratitude to my research advisor, Dr. Mark D. Soucek, for his invaluable guidance and encouragement throughout my doctoral dissertation. I also would like to extend my gratitude towards my committee members, Dr. Kevin Cavicchi, Dr. Avraam I. Isayev, Dr. Li Jia, and Dr. Chrys Wesdemiotis for their contribution, suggestion, and support. I would like to thank Dr. Bryan Vogt for giving me a great opportunity for the research cooperation related to the application of mesoporous materials. Sarang Bhaway has put tons of effort in order to make this study happen i.e. fabrication of mixed metal oxide mesopores materials, characterization, and valuable discussion. I would like to thank Dr. Nicole Zacharia, Dr. Yuanqing (Kane) Gu, and Jon R. Page for their help and guidance with GPC characterization. I would like to thank the University of Akron Magnetic Resonance Center, Dr. Venkat Dudipala, Chun Gao, and Stephanie Bilinovich for their experimental support and valuable discussion. I also would like to thank the University of Akron Mass Spectrometry Center, Dr. Aleer M. Yol, Michelle Kushnir, and Selim Gerislioglu for their experimental support and discussion. This research would not have been possible without the financial assistance from Euclid Chemical Company. In particular, I would like to thank Keith Franey, John v Langham, Brad Nemunaitis, Arthur Greenberg, and Jane Krivos for their experimental help, guidance, and encouragement. I would like to thank my research group members for their encouragement and help given to me during my research work. I am grateful to Ali Javadi for his helpful discussion related to my doctoral dissertation. Finally, I would like to dedicate this doctoral dissertation to my family for their love and support in every stage of my life. vi TABLE OF CONTENTS Page LIST OF FIGURES ......................................................................................................... xiii LIST OF SCHEMES........................................................................................................ xix LIST OF TABLES ............................................................................................................ xx CHAPTER I. INTRODUCTION ........................................................................................................... 1 II. BACKGROUND ............................................................................................................ 6 2.1 Concrete .................................................................................................................... 6 2.1.1 Manufacture of cement ...................................................................................... 8 2.1.2 Basic compositions of cement ........................................................................... 9 2.1.3 Major oxide compounds of ordinary Portland cement .................................... 10 2.1.4 Minor oxide compounds of ordinary Portland cement .................................... 12 2.1.5 Setting and hardening of cement...................................................................... 13 2.1.6 Hydration reactions of cement ......................................................................... 14 2.1.7 Development of cement paste structure ........................................................... 16 2.2 Admixtures in concrete ........................................................................................... 17 2.2.1 Air-entraining agents ....................................................................................... 18 2.2.2 Defoaming agents ............................................................................................ 18 2.2.3 Accelerating admixtures .................................................................................. 19 2.2.4 Retarding admixtures ....................................................................................... 19 2.2.5 Waterproofing admixtures ............................................................................... 19 vii 2.2.6 Corrosion-inhibiting admixtures ...................................................................... 19 2.2.7 Dispersing admixtures ..................................................................................... 20 2.3 Mechanism of air-entraining agents in concrete ..................................................... 21 2.4 Mechanism of defoaming agents in concrete.......................................................... 24 2.5 Mechanism of dispersing admixtures in concrete ................................................... 27 2.6 Mesoporous materials ............................................................................................. 29 2.6.1 Classification of porous materials .................................................................... 29 2.6.2 Synthesis mechanism for the creation of mesoporous materials ..................... 30 2.6.3 Applications of mesoporous materials ............................................................. 38 2.7 Thickeners for water-based coating systems .......................................................... 39 2.8 Radical copolymerization and controlled radical copolymerization ...................... 40 III. THE SYNTHESIS AND CHARACTERIZATION OF STARTING MATERIALS: METHOXY POLY (ETHYLENE GLYCOL) METHACRYLATE AND WATER SOLUBLE RAFT AGENT ............................................................................................... 46 3.1 Overview ................................................................................................................. 46 3.2 Materials ................................................................................................................. 46 3.3 Instrumentation ....................................................................................................... 47 3.4 Synthesis ................................................................................................................. 48 3.4.1 Synthesis of methoxy poly (ethylene glycol) methacrylate (MPEGMA) ....... 48 3.4.2 Synthesis of 2-Methyl acrylic acid (dibuthoxy-phosphoryloxy) – alkyl ester . 50 3.4.3 Synthesis of water soluble RAFT agent: 4-cyanopentanoic acid dithiobenzoate (CPADB)..................................................................................................................
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