Macromolecular architectures based on well defined poly(pentafluorostyrene) design, synthesis, characterization and applications

MACROMOLECULAR ARCHITECTURES BASED ON WELL-DEFINED POLY(PENTAFLUOROSTYRENE): DESIGN, SYNTHESIS, CHARACTERIZATION AND APPLICATIONS FU GUODONG (M ENG BUCT) A THESIS SUBMITTED FOR THE DEGREE OF DOCTOR OF PHILOSOPHY DEPARTMENT OF CHEMICAL &BIOMOLECULAR ENGINEERING NATIONLA UNIVERSITY OF SINGAPORE 2005 ACKNOWLEDGEMENT First of all, I would like to express my deepest gratitude to my supervisors, Professor Kang En-Tang and Professor Neoh Koon-Gee, for the heartfelt guidance, invaluable suggestions, profound discussion and encouragement throughout the period of this research work Their enthusiasm, sincerity and dedication to scientific research have greatly impressed me and will benefit me in my future career I would like to thank all my colleagues and the laboratory officers of the Department of Chemical and Biomolecular Engineering for their kind help and assistance In particular, thanks are due to Dr Lin Qidan, Dr Cheng Zhenping, Dr Wang Wencai and Mr Cai Qinjia for their helpful advice and discussion It is my great pleasure to work with all of them I am also indebted to Dr Chen Lingfeng for the material characterization The research scholarship provided by National University of Singapore is also gratefully acknowledged Finally, I would like to express my deepest gratitude and indebtedness to my wife, my parents, my daughter, my sister and brother for their love and support I TABLE OF CONTENTS Acknowledgement I Table of Contents -II Summary -V Nomenclature VIII Lists of Figures X List of Tables -XVI Chapter Introduction Chapter Literature Review -9 2.1 Applications and Physicochemical Properties of Fluoropolymers 10 2.2 Macromolecular Architectures, Design and Synthesis -11 2.2.1 Macromolecular Architectures via ATRP -12 2.2.2 Functional Copolymers Prepared via ATRP 15 2.2.3 Fluoro-Block Copolymers Prepared via ATRP -16 2.3 Ultra-Low-κ Materials 19 2.3.1 Preparation of Fluoropolymer-based Dielectrics -19 2.3.2 Nanoporous Low-κ Materials -20 2.4 Amphiphilic Block Copolymers -23 2.4.1 Application of Amphiphilic Block Copolymers as Emulsifiers 24 2.4.2 Application of Amphiphilic Block Copolymers in Drug Delivery -25 2.4.3 Application of Amphiphilic Block Copolymers in Structure-controlled Nanomaterials 26 II Chapter Comb-Shaped Macromolecules of Rigid Fluorinated Polyimides with Polystyrene/Poly(pentafluorostyrene) Brushes Prepared by ATRP and Their Application as Ultra-Low Dielectric Constant Materials 3.1 Introduction -30 3.2 Experimental 31 3.3 Results and Discussion 38 3.4 Conclusions -57 Chapter Nanoporous Ultra-Low Dielectric Constant Fluoropolymer Films via Selective UV Decomposition of Poly(pentafluorostyrene-blockmethylmethacrylate) Copolymers Prepared by ATRP 4.1 Introduction -59 4.2 Experimental 60 4.3 Results and Discussion 64 4.4 Conclusions -83 Chapter Nanoporous Ultra-Low-κ Fluoropolymer Films from Agglomerated and Crosslinked Hollow Nanospheres of Poly(pentafluorostyrene)-block-Poly(divinyl benzne) 5.1 Introduction -85 5.2 Experimental 88 5.3 Results and Discussion 90 5.4 Conclusions 100 III Chapter Three-Dimensionally-ordered Porous Membrane from the Self-Assembly and Reverse Micelle formation of Amphiphilic Poly(pentafluorostyrene-block-acrylic acid) Block Copolymer Prepared by ATRP 6.1 Introduction 102 6.2 Experimental -104 6.3 Results and Discussion -108 6.4 Conclusions 120 Chapter Tadpole-shaped Amphiphilic Block-Graft Poly(pentafluorostyrene) -block-(poly(glycidyl methacrylate)-graft-poly(acrylic acid)) Prepared Copolymers via Consecutive Atom Transfer Radical Polymerizations and Their Micelle Formation 7.1 Introduction 122 7.2 Experimental -124 7.3 Results and Discussion -130 7.4 Conclusions 149 Chapter Conclusions and Recommendations for Future work 150 References -155 List of Publications 170 IV Summary Fluoropolymers are potential candidates for dielectric interlayer because of their good chemical and thermal stability, and the lowest dielectric constants (κ’s) among the bulk polymers However, their applications in sub-micron and nano-level electronics are hindered by difficulties in processing Amphiphilic fluoropolymers with well-defined molecular weight, controllable chemical component, and various molecular structures are of great interest because of their unique solution and associative properties The aims of this thesis were to prepare well-defined fluoropolymers and copolymers with favorable solution properties, as well as to prepare ultra-low-κ (