Probing Gas Transport Structure-Property Relationships in Vinyl-Addition Polynorbornenes

Polynorbornenes are ideal materials for systematic structure-property investigations designed to correlate gas-transport properties to polymer structure. The modular nature of norbornene-derived systems provides a facile route towards the synthesis of diverse polymeric materials, whose structure may be systematically altered through targeted design of monomers, alterations in polymerization mechanism, or some combination of these two strategies. Though many valuable correlations between gas-permeability and polynorbornene structure have been summarized in prior literature, many of these efforts have focused on homopolymer materials with structural changes imposed — almost exclusively — through modifications in substituent chemistry, or through targeted modulation of molar ratios in statistical copolymer materials. My graduate work has utilized this established strategy with a later focus on understanding the role of microstructure on gas transport.

Chapter I will present an introductory review of literature reporting gas transport properties in select polynorbornene based membranes. Materials selected for introductory discussion bear structural resemblance to the materials that will be discussed in Chapters II and III. Chapter II will present work inspired by the established strategy of compositionally tuned copolymer synthesis where the influence of fluorine content on CO₂/CH₄ separation performance was investigated. Chapter III will discuss our most recent efforts to correlate gas transport properties with microphase separated structure through the design, synthesis, and fabrication of self-assembled diblock copolynorbornenes. Chapter IV will present concluding remarks, as well as a perspective outlook regarding the field of gas separation membranes derived from vinyl-addition polynorbornenes.