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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 series of silyl ether amine curing agents were synthesized by selective substitution reactions of chloroalkylsilanes or the transetherification of alkoxysilanes. Crosslinked networks were prepared by mixing a stoichiometric ratio of bisphenol A diglycidyl ether (D.E.R 331) with the amine curing agents. The networks were characterized by ATR-FTIR spectroscopy, TGA, DSC, and DMA. The onset of thermal degradation, glass transition temperatures, and storage moduli for the networks were 350 °C, 70–108 °C, and 5–25 MPa, respectively. The degradation behavior of the cured samples was monitored for 30 days in PBS, NaOH 5% (w/v), and HCl 5% (v/v) solutions and the degradation products were characterized by spectroscopic methods. The thermal, mechanical, and degradation studies indicated that crosslink density, Tg, storage modulus, and the rate of degradation were affected by the functionality of the amine curing agents and the number of hydrolyzable silyl ether bonds present per mole of curing agent. © 2016 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 44620.

Asymmetric membranes of phenylated polyphenylene were prepared by wet phase inversion. The polyphenylene (Mn = 62 kDa, PD = 2.3) was prepared by Diels–Alder polymerization of 1,4-bis(tetraphenylcyclopentadienonyl)benzene with 1,4-diethynylbenzene at 180°C. Solvents and non-solvents were experimentally identified and solvent : non-solvent systems were evaluated by the quality of the resulting membranes. Cyclohexanone/n-butanol (88 : 12) as solvent and n-butanol as the non-solvent were found to afford the best asymmetric membranes with minimal defects. Membranes (20–30 µm thick) from coagulating 11.5 wt % polyphenylene from cyclohexanone/n-butanol in n-butanol baths exhibited 250–300 nm, non-porous skins overlaying 20–30 µm of open-celled, spongiform structure. Due to a relatively high glass transition temperature of 370°C, the phenylated polyphenylene membranes retained their porosity to 200°C higher than polysulfone asymmetric membranes. © 2012 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013

A diverse pool of aryl bistrifluorovinyl ether (BTFVE) compounds with reactive pendant groups were prepared in a facile, high yielding three step “one-pot” synthesis from commercial 4-bromo(trifluorovinyloxy)benzene. Monomers were confirmed from ATR–FTIR, 1H, 13C, and 19F NMR, and HRMS analysis. Aryl BTFVE compounds were thermally polymerized to afford perfluorocyclobutyl (PFCB) aryl ether polymers with high number–average molecular weight (Mn) for homopolymers (17,050–27,090) and copolymers with 4,4′-bis(trifluorovinyloxy)biphenyl monomers (27,860–56,500). The PFCB aryl ether homo- and copolymers collectively possess high thermal stability (>299 °C in N2) and are readily solution processable producing optically transparent films. The thermal polymerization was achieved and reactive moieties remained intact, aside from those functionalized with acrylates. In the case with acrylate functionalized polymers, orthogonal polymerization was achieved by first photopolymerizing the acrylates followed by thermal curing of the aryl trifluorovinyl ether endgroups. Preliminary results in this study produced the successful preparation of photodefinable PFCB aryl ether material. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1887–1893, 2010

This article highlights the preparation of perfluorocyclobutyl (PFCB) aryl ether polymers for a multitude of commercial technologies that are of academic and commercial global interest. In this account, the synthesis of various aryl trifluorovinyl ether (TFVE) monomers tailored for specific applications is discussed. The preparation of PFCB aryl ether polymers and their properties is then presented. Topics of PFCB aryl ether polymers and their applications include photonics, polymer light emitting diodes (PLEDs), proton exchange membranes (PEMs) for fuel cells, atomic oxygen (AO) resistant coatings, and hybrid composites.