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Transparent, film-forming fluorinated arylene vinylene ether (FAVE) polymers with enchained triarylamine (TAA) moieties were prepared and characterized. Control over fluoro-olefin content within the backbone, as a function of base, was confirmed and postpolymerization dehydrofluorination was shown to increase fluoroolefin content from 5 to 31 mol %. Thermal cross-linking was found to occur approximately 100 °C lower than in traditional FAVE polymers (ca. 160 °C). Electrochemical analysis demonstrated the enchained TAA retained its established electrochemical character. The latent reactivity of the TAA was explored via electrophilic aromatic substitution and formylation reactions toward precise functionalization for specific electro-optic applications and others.

Thiol-click reactions lead to polymeric materials with a wide range of interesting mechanical, electrical, and optical properties. However, this reaction mechanism typically results in bulk materials with a low glass transition temperature (Tg ) due to rotational flexibility around the thioether linkages found in networks such as thiol-ene, thiol-epoxy, and thiol-acrylate systems. This report explores the thiol-maleimide reaction utilized for the first time as a solvent-free reaction system to synthesize high-Tg thermosetting networks. Through thermomechanical characterization via dynamic mechanical analysis, the homogeneity and Tg s of thiol-maleimide networks are compared to similarly structured thiol-ene and thiol-epoxy networks. While preliminary data show more heterogeneous networks for thiol-maleimide systems, bulk materials exhibit Tg s 80 °C higher than other thiol-click systems explored herein. Finally, hollow tubes are synthesized using each thiol-click reaction mechanism and employed in low- and high-temperature environments, demonstrating the ability to withstand a compressive radial 100 N deformation at 100 °C wherein other thiol-click systems fail mechanically.

Suzuki polycondensation (SPC) as an alternative strategy has been utilized for the first time to readily yield functional perfluorocyclobutyl (PFCB) aryl ether polymers, which are difficult to obtain via the traditional [2+2] thermal cyclopolymerization strategy. Using two reactive PFCB aryl ether molecules as monomers, the biphenyl PFCB aryl ether polymer without any functionality was first prepared and exhibited good thermal stability, up to 450 °C at 8% weight loss (N2). By choosing appropriate functional monomers, aldehyde-functionalized PFCB aryl ether polymer precursor was also successfully prepared. Post-polymerization modification of this polymer precursor via Knoevenagel condensation yielded three distinct PFCB aryl ether polymers containing thermally stable triarylamine-based electro-optic chromophores.

A series of N-alkyl/aryl carbazole 3,6-substituted arylene trifluorovinyl ether (TFVE) monomers were synthesized in high purity and yield from a concise four-step synthesis using carbazole as a starting material. Condensate-free, step-growth chain extension of the monomers afforded perfluorocyclobutyl (PFCB) arylene ether homo- and copolymers as solution processable, optically transparent blue-light emissive materials. Arylene TFVE monomers and conversion to PFCB arylene ether polymers were structurally elucidated and purity confirmed by high resolution mass spectroscopy, NMR (1H, 13C, and 19F) spectroscopy, gel permeation chromatography, and attenuated total reflectance Fourier transform infrared analysis. Thermal analysis by differential scanning calorimetry and thermogravimetric analysis revealed glass transition temperatures >150 °C and onset of decomposition in nitrogen >410 °C with 40 wt % char yield up to 900 °C. Optical and electrochemical studies included solution (tetrahydrofuran) and solid state (spin cast thin film) UV–vis/fluorescence spectroscopy and cyclic voltammetry which showed structure dependence of these blue emissive systems on the nature of the N-alkyl/aryl carbazole substitution in either homo- or copolymer configurations. © 2013 Wiley Periodicals, Inc. J. Polym. Sci., Part A: Polym. Chem. 2014, 52, 552–560

A unique class of aromatic ether polymers containing perfluorocyclopentenyl (PFCP) enchainment was prepared from the simple step growth polycondensation of commercial bisphenols and octafluorocyclopentene (OFCP) in the presence of triethylamine. Model studies indicate that the second addition/elimination on OFCP is fast and polycondensation results in linear homopolymers and copolymers without side products. The synthesis of bis(heptafluorocyclopentenyl) aryl ether monomers and their condensation with bisphenols further led to PFCP copolymers with alternating structures. This new class of semifluorinated polymers exhibit surprisingly high crystallinity in some cases and excellent thermal stability.