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A series of six new polyarylene polyimides (PAPI) was prepared from a highly phenylated phenylenediamine synthesized via a Diels–Alder reaction. The diamine was reacted with a variety of dianhydrides using a one-step microwave-assisted step-growth polycondensation reaction to give the PAPI. The polymerizations were complete in 10 to 30 minutes using isoquinoline as catalyst. Yields as high as 99% were achieved using nitrobenzene as the solvent. A semi-fluorinated dianhydride was included to compare polyimide properties to the hydrocarbon materials. Full characterization was carried out via1H and 19F nuclear magnetic resonance spectroscopy and attenuated total reflectance Fourier transform infrared spectroscopy. Thermal properties were characterized via thermal gravimetric analysis and differential scanning calorimetry. The onset of thermal degradation was approximately 550 °C in nitrogen and air atmospheres while the char yields at 1000 °C in nitrogen were almost 70%. The semi-fluorinated polyarylene polyimide exhibited the highest char yield. Glass transition temperatures were in the range of 355 to 387 °C, with the semi-fluorinated material possessing the highest Tg and the most rigid material affording the lowest Tg. Optical transparency was good in all the materials, with the semi-fluorinated material having the largest optical window in the UV-Vis region. The polymers were colorless or pale yellow solids. Solubility was excellent in chloroform, tetrahydrofuran, toluene, and cyclohexanone. We are currently interested in these materials and precursors for fuel cell and gas separation membranes, coatings, fibers, adhesives, and composite applications.

This data article describes a detailed synthetic strategy and experimental data for the synthesis of brominated fulvene chromophores as reactive precursors/monomers for conjugated organic materials. Metal-mediated coupling reactions of brominated fulvenes would result in conjugated small molecules or polymers that would find application as organic light emitting diodes (OLEDs) and photovoltaic (PV) applications.

Acetylene- and diacetylene-containing organosilicon polymers continue to be of great interest in academia, government, and industry due to their high thermo-oxidative stability combined with excellent solubility and processability characteristics. Progress in this field over the past 30 years is reported herein. We present and discuss the synthesis, characterization, and structure–property relationships related to these materials. Furthermore, properties for specific applications of these polymers are briefly summarized, such as absorption and emission spectroscopy, composite mechanical analysis, four-probe conductivity measurements, and electroluminescence.

Boron nitride nanotubes (BNNTs) were successfully functionalized with ethynyl groups using hypervalent iodine. High molecular weight polyarylene was synthesized via microwave-assisted polymerization. Polyarylene-BNNT nanocomposite materials were prepared and characterized for the first time. Thermal stability in air of the nanocomposites was excellent. The functionalization of nanotubes as described opens a new pathway to future materials in the defense, aerospace, automotive, and biomedical fields.

Gold nanoparticles (GNPs) have a wide range of properties with potential applications in electronics, optics, catalysis, and sensing. In order to demonstrate that dense, stable, and portable samples could be created for these applications, multiple layers of GNPs were assembled via drop casting on glass substrates by layer-by-layer (LBL) techniques. Two cationic polyelectrolytes, poly(diallyldimethylammonium chloride) and polyethyleneimine, one anionic polyelectrolyte, poly(sodium 4-styrene sulfonate), and one neutral polymer, polyvinylpyrrolidone, were combined with four different shapes of GNPs (spherical, rod, triangular prismatic, and octahedral) to prepare thin films. A subset of these polymer nanoparticle combinations were assembled into thin films. Synthesized GNPs were characterized via dynamic light scattering, UV-vis spectroscopy, and transmission electron microscopy and the LBL thin films were characterized using UV-vis spectroscopy and atomic force microscopy. Sensing applications of the nanoparticles in solution and thin films were tested by monitoring the localized surface plasmon resonance of the GNPs. LBL thin films were prepared ranging from 25 to 100 layers with optical densities at plasmon from 0.5 to 3.0. Sensitivity in solutions ranged from 14 to 1002nm/refractive index units (RIU) and films ranged from 18.8 to 135.1nm/RIU suggesting reduced access to the GNPs within the films.

For energy storage to become ubiquitous in the electric grid, safe, reliable low-cost electrochemical storage technologies manufactured at high volumes with low capital expenditures are needed. Alkaline batteries based on high capacity multi-electron conversion electrodes from low cost, abundant and safe materials, such as a Zn/MnO2 are a promising technology. These batteries have a theoretical specific energy rivaling that of Li-ion systems (Zn @820 mAh/g and MnO2 @617 mAh/g, with ~400 Wh/L) and costs reducible to et al.). While recent advances by Yadav et al. have demonstrated highly reversible Bi- and Cu-stabilized MnO2 electrodes that can achieve the full 2e- capacity of MnO2 in alkaline electrolyte, the ability to pair this electrode with Zn over 5000+ cycles, which equates to ~10-15 years of battery life, remains a difficult challenge. Zn anodes suffer from irreversible shape change, the redistribution of active material, and passivation over repeated charge and discharge, limiting their achievable capacity and lifetime. Pre-saturating the electrolyte with zincate [Zn(OH)4 2-], which minimizes dissolution of Zn from the anode and reduces the rate of hydrogen evolution, has recently been shown to enhance cycle life for ~10-35% depth-of-discharge (DOD) Zn anodes by ~100-200% (M. Lim et al.); however, Zn(OH)4 2- saturated electrolyte is incompatible with high DOD MnO2, and exacerbates the formation of electrochemically inactive phases, such as ZnMn2O4 at the cathode. Hence, using zincate-blocking separators, able to entrap the zincate within the anode and effectively isolate the MnO2 cathode from Zn(OH)4 2- crossover, while maintaining hydroxide/cation conductivity, is one approach to improve the reversible cycling of a Zn/MnO2 cell at high DOD of both MnO2 and Zn. More recently we have developed a series of permselective polymeric separators (Kolesnichenko et al.) and screened them using our newly-developed anodic stripping voltammetry crossover assay (Duay et al.) to identify those with Zn(OH)4 2- blocking ability. A primary discharge of MnO2 was used to demonstrate that a sustained 2nd e- discharge plateau, indicative of the absence of zinc species at the cathode, was observed only for Zn/MnO2 batteries that utilized our selective polymeric separators. Finally, application of these polymeric separators in rechargeable Zn/MnO2 batteries increased cycle life with higher coulombic efficiencies. Various aspects involved in improving the cycle life of Zn anodes at increased DOD, and of the application of polymeric separators in isolating the MnO2 cathode from soluble zincate and their ability to enable higher DOD cycling in Zn, will be discussed. This work was supported by the U.S. Department of Energy, Office of Electricity, and the Laboratory Directed Research and Development program at Sandia National Laboratories. Sandia National Laboratories is a multi-program laboratory managed and operated by National Technology and Engineering Solutions of Sandia, LLC., a wholly owned subsidiary of Honeywell International, Inc., for the U.S. Department of Energy's National Nuclear Security Administration under contract DE-NA-0003525. The views expressed herein do not necessarily represent the views of the U.S. Department of Energy or the United States Government. References [1] S. Banerjee S. Banerjee, Alkaline Zn-MnO2 Battery Development: A University-Private-Public Partnership, in Department of Energy Office of Electricity and Energy Reliability Peer Review, Santa Fe, NM, September 25-27th, 2018., https://eesat.sandia.gov/ wp-content/uploads/2018/10/1_SanjoyBanerjee_Presentation.pdf [2] G. G. Yadav, J. W. Gallaway, D. E. Turney, M. Nyce, J. Huang, X. Wei and S. Banerjee, Nat. Commun., 8, 14424 (2017). [3] M. B. Lim, T. N. Lambert and E. I. Ruiz “Effect of ZnO-Saturated Electrolyte on Rechargeable Alkaline Zinc Batteries at Increased Depth-of-Discharge” J. Electrochem. Soc. 2020, 167, 060508. DOI:10.1149/1945-7111/ab7e90. [4] J. Duay, M. Kelly and T. N. Lambert J. Power Sources, 395, 430-438 (2018). [5] I. Kolesnichenko et al. manuscript submitted. [6] J. Duay, T. N. Lambert and R. Aidun Electroanal 29, 2261-2267 (2017).

Silica aerogels were silated with coumarin functionalities to allow for strengthening through the photochemical dimerization of the coumarin groups. Coumarin modified silica gels were prepared by either co-polymerizing tetramethoxysilane (TMOS) with small amounts of 7-(3-triethoxysilylpropoxy)coumarin (TEPC) or by surface modifying the silica gel with 7-(3-trimethoxysilylpropoxy)coumarin (TMPC). Aerogels, prepared by supercritical carbon dioxide drying, were irradiated with ultraviolet light (365 nm) for varying lengths of time and the flexural strength of cylindrical samples was measured. Copolymerization of TEPC with TMOS resulted in aerogels that, while initially weaker than pure silica aerogels, showed a 41% increase in flexural strength with 20 min exposure to UV. In contrast, the surface modified aerogels, while stronger than pure silica aerogels, showed no influence on flexural strength with exposure to UV.

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.

A new PFCP-based chlorosilane monomer containing a latent reactive fluorine atom was synthesized utilizing a hydrosilylation reaction. This monomer was used to functionalize Stöber silica nanoparticles, or network silicas, and the ability to tailor the properties of the functionalized nanoparticles was investigated by reacting the latent reactive fluorinated alkene with various nucleophiles. In order to model the chemical transformations occuring with the PFCP-functionalized particles, a new PFCP-containing molecular silica was prepared using a hydrosilylation reaction. The molecular silica was designed such that it contained a latent reactive fluorine atom and could also undergo post-synthetic modifications with various nucleophiles. The ability to modify the latent reactive group and tune the properties of the molecular and network silicas was verified by multi-nuclear NMR ((1)H, (13)C, (19)F, and (29)Si), thermal characterizations, and by investigating the hydrophobicity and surface morphology of spin-cast films prepared from the molecular and network silicas.

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

The title compounds, C66H46, (I), and C66H42F4, (II), are polyphenylated arylenes synthesized by one-step Diels–Alder cycloaddition reactions. In both structures, all molecules lie on crystallographic inversion centers. In the case of (I), there are two half-molecules present in the asymmetric unit, (IA) and (IB); the geometry of each half-molecule differs principally in the magnitudes of the dihedral angles between mean planes fitted through the central aryl ring and the pendant phenyl rings. The crystal used was a non-merohedral twin, with a refined twin scale factor of 0.460 (8). The dihedral angle between the plane of the central tetrafluorinated ring and the adjacent tetraphenylated ring in (II) is 83.87 (4)°, significantly greater than the dihedral angles of 49.89 (12) and 54.38 (10)° found in the two half-molecules in (IA) and (IB), respectively, and attributed to intermolecular C—H...F hydrogen bonding in (II). Intermolecular C—H...π bonding is found in (I). Two interactions have the C—H bond oriented towards the centroid (Cg) of a butadiene fragment of a phenyl ring; both H...Cgdistances are approximately 2.68 Å and the interactions connect adjacent molecules into stacks in thec-axis direction. The composition of the stacks alternates,i.e.(IA)–(IB)–(IA)–(IB)etc. A third, weaker, C—H...π interaction and a phenyl–phenyl close contact connect each end of the long molecular axes of (IB) with an adjacent molecule of (IA) into chains which run perpendicular to the (140) and (\overline{1}40) planes. C—H...F interactions in (II) have the most profound influence on the molecular and crystal structure, the main effect of which is the above-mentioned increase in the dihedral angle between the plane of the central tetrafluorinated ring and the adjacent tetraphenylated ring. C—H...F interactions have refined H...F distances of 2.572 (15) and 2.642 (16) Å, with approximate C—H...F angles of 123 and 157°, respectively. These form a hydrogen-bonded ribbon structure which propagates in theb-axis direction.

Acrylonitrile/1-vinylimidazole (AN/VIM) copolymers containing various mol% of VIM were synthesized by free radical solution polymerization. The copolymers were characterized by Attenuated Total Reflectance-Fourier Transform Infrared (ATR-FTIR) spectroscopy, 1H NMR spectroscopy, gel permeation chromatography (GPC) and differential scanning calorimetry (DSC). Char yields of the copolymers were 40–48% as determined by thermogravimetric analysis (TGA) while gel fractions were found to be 90–99% depending upon the composition, temperature and time. The complex viscosity of the precursor copolymers was measured as a function of composition and temperature. 82/18 mol% of AN/VIM copolymer based carbon fiber precursor was successfully processed by solvent-free melt spinning at 192 °C and the melt-spun fiber was characterized by DSC, ATR-IR, and X-ray Diffraction (XRD).

We derive an analytical model of diffusive thermal transport in multilayer structures of spherical symmetry and apply it to transient thermoreflectance measurements of gold nanoparticles embedded in a polymer matrix. This multilayer approach significantly improves the quantitative measurement of material thermal properties, in comparison with single-layer methods. The model adapts the typical planar transfer matrix model to a spherical geometry, and we apply it to transient thermoreflectance (TTR) experiments on gold nanoparticles embedded in a polymer matrix, to published TTR data for aqueous platinum nanoparticles, and also to example systems of aqueous gold and platinum nanoparticles. We measure a thermal boundary conductance value of 410MW/m2K at the nanoparticle gold/polymer interface. The sensitivity of the TTR signal to system thermal properties is predicted as a function of the particle/matrix thermal boundary resistance (TBR), and we discuss the differentiation of TBR and capping layer effects on a TTR signal.We derive an analytical model of diffusive thermal transport in multilayer structures of spherical symmetry and apply it to transient thermoreflectance measurements of gold nanoparticles embedded in a polymer matrix. This multilayer approach significantly improves the quantitative measurement of material thermal properties, in comparison with single-layer methods. The model adapts the typical planar transfer matrix model to a spherical geometry, and we apply it to transient thermoreflectance (TTR) experiments on gold nanoparticles embedded in a polymer matrix, to published TTR data for aqueous platinum nanoparticles, and also to example systems of aqueous gold and platinum nanoparticles. We measure a thermal boundary conductance value of 410MW/m2K at the nanoparticle gold/polymer interface. The sensitivity of the TTR signal to system thermal properties is predicted as a function of the particle/matrix thermal boundary resistance (TBR), and we discuss the differentiation of TBR and capping layer effects o...

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

Semifluorinated polymers incorporating π-conjugated segments diphenylbithiophene and a distyrylbenzene derivative as chromophoric main chain subunits have been prepared via a transition metal-free polymerization technique, and explored as anion sensors. One polymer exhibits visually identifiable colorimetric changes and photoluminescence enhancement in response to fluoride or cyanide over other common anions such as OAc − , P 2 O 7 4− , Cl − , Br − , I − , PO 4 3− , or HSO 4 − in THF. Modest dissociation constants of 4.5 × 10 −5 M and 6.7 × 10 −3 M were determined for binding of fluoride and cyanide, respectively, to the most responsive polymer.

A convenient route to enhancing the thermal degradation on-set temperature of existing commercial optical fiber coatings is presented. UV curable acrylate coatings were modified through the addition of a multi-functional cross-linking agent and are shown to increase their degradation temperature by 65degC without any degradation in the mechanical or optical properties of the resultant fiber. Such enhanced thermal robustness in coatings is important for optical fiber applications in high energy laser (HEL) systems and selected higher temperature sensing environments.

New fluorinated arylene vinylene ether (FAVE) polymers were prepared by a facile, metal-free condensation polymerization of fluorene, phenylenevinylene, dithiophene, or thiadiazole chromophore-containing bisphenols with bis(trifluorovinyloxy)biphenyl. The addition of chromophores encapsulated into the polymers were prepared in good yields and characterized by 1H and 19F NMR and GPC. Thermal analysis by differential scanning calorimetry (DSC) confirmed the polymers are entirely amorphous and are easy to solution process, producing optically transparent, flexible films. Thermal gravimetric analysis (TGA) showed they possess high thermal stability with decomposition temperatures of 340−387 °C and 308−443 °C in nitrogen and air, respectively. Chromophore inclusion was confirmed by ultraviolet−visible (UV−vis) spectroscopy, which demonstrated tailorable photoluminescence (PL) in both the solution and the solid state by selective substitution of the chromophore. Polymer thin film PL studies revealed notable red...

The synthesis and hyperpolarizabilities of a series of push−pull chromophores containing a bis-(4-methoxyphenyl) amine donor and efficient acceptor bridges with thiophene and ring-locked polyene are presented. The chromophores are readily soluble in common organic solvents and exhibit high thermal decomposition temperatures (highest Td was 358 °C). Molecular hyperpolarizabilities (β) of the chromophores were measured by hyper-Raleigh scattering at 1604 nm (highest β was 20 000 × 10−30 esu). The electrochemical behavior of the chromophores was studied by cyclic voltammetry and agreed well with the observed intrinsic nonlinearities. In addition, preliminary results of conjugated polyene chromophores containing aryl trifluorovinyl ether monomers were synthesized and copolymerized via thermal cyclodimerization, affording perfluorocyclobutyl aryl ether polymers with high glass transitions (highest Tg was 224 °C) and a good thermal stability (typical Td was >350 °C). These chromophores can be used to develop el...

The synthesis and characterization of solution processable, semi-fluorinated perfluorocyclobutyl (PFCB) aryl ether polymers possessing covalently bound pendant polyhedral oligomeric silsesquioxanes (POSS) cages is reported. The synthesis of POSS aryl trifluorovinyl ether (TFVE) monomers was accomplished by the condensation of commercial monosilanolalkyl-POSS with a TFVE-functionalized chlorosilane. POSS TFVE monomers were elucidated by 1H, 19F, 13C, and 29Si NMR spectroscopy, ATR-FTIR analysis, and elemental (C, H, and F) combustion analysis. Bulk thermal copolymerization of POSS TFVE monomers afforded random and block PFCB aryl ether copolymers functionalized with various POSS loadings. Quantitative monomer conversion was monitored by 19F NMR, which produced copolymer number-average molecular weights (Mn) of (19.5−24.9) × 103 (in CHCl3 using polystyrene as standard) determined by gel permeation chromatography (GPC). Thermal properties of POSS PFCB aryl ether copolymers were evaluated by differential scan...

The first report of perfluorocyclobutyl (PFCB) aryl ether polymer colloids is presented herein. The biphenyl rings were post-functionalized with chlorosulfonic acid modification in the backbone of the perfluoropolymer, thereby changing the zeta potential (ζ) of the colloids across the pH range (2–12). Self-assembly of the colloids was observed by scanning electron microscopy (SEM) on four separate surfaces which led to different morphological changes for each surface; spherical on Al substrate, clover-like on Cr substrate, flower-like on carbon substrate, and “squalloid” on Si substrate.

There is a growing need for optical fiber coatings that can sustain higher temperatures than present materials permit. To date, polyimides are used predominantly but they generally are difficult to process and usually require multiple depositions to achieve the desired film thickness. Perfluorocyclobutyl (PFCB) aryl ether polymers have demonstrated much success as processable and amorphous fluoropolymers,[1] with particular emphasis on high performance optical applications.[2] This work discusses recent efforts into perfluorocyclobutyl aryl ether polymer-based optical fiber coatings.[3] A series of silica-based optical fibers were drawn with differing PFCB polymer coatings compositions and molecular weights on a Heathway draw tower. Results include a more than doubled usage temperature of coating (decomposition temperatures (Td) in nitrogen and air were above 450 °C) without affecting fiber mechanical properties and comparable isothermal stability to conventional coatings, except with a >150 °C higher temperature. Preliminary results of the first successful coating of optical fibers by PFCB polymers will be presented herein, as well as future endeavors.

Fluoropolymers have long served as potent oxidizers for metal-based pyrolant designs for the preparation of energetic materials. Commercial perfluoropolyethers (PFPEs), specifically known as Fomblins®, are well-known to undergo accelerated thermal degradation in the presence of native metals and Lewis acids producing energetically favorable metal fluoride species. This study employs the use of PFPEs to coat nano-aluminum (n-Al) and under optimized stoichiometric formulations, harness optimized energy output. The PFPEs serve as ideal oxidizers of n-Al because they are non-volatile, viscous liquids that coat the particles thereby maximizing surface interactions. The n-Al/PFPE blended combination is required to interface with an epoxy-based matrix in order to engineer a moldable/machinable, structurally viable epoxy composite without compromising bulk thermal/mechanical properties. Computational modeling/simulation supported by thermal experimental studies showed that the n-Al/PFPE blended epoxy composites produced an energetic material that undergoes latent thermal metal-mediated oxidation. Details of the work include the operationally simple, scalable synthetic preparation, thermal properties from DSC/TGA, and SEM/TEM of these energetic metallized nanocomposite systems. Post-burn analysis using powder XRD of this pyrolant system confirms the presence of the predominating exothermic metal-mediated oxidized AlF3 species in addition to the production of Al2O3 and Al4C3 during the deflagration reaction. Details of this first epoxy-based energetic nanocomposite entrained with a thermally reactive formulation of PFPE coated n-Al particles are presented herein.

Composite fluoropolymers were prepared by solvent blending fluorinated POSS (F-POSS) with perfluorocyclobutyl (PFCB) aryl ether polymers. The semifluorinated PFCB aryl ether polymers were shown to be hydrophobic, but demonstrated complete wetting by hydrocarbon-based liquids. Upon the incorporation of F-POSS as a drop-in modifier at low weight percent loadings, the composite fluoropolymer spin cast films exhibited increased water in addition to hydrocarbon repellency as determined by contact angle analysis. Composite film surface characterization included SEM and AFM analyses which showed excellent F-POSS dispersion and increased surface roughness. Thermal properties of the blended films were analysed using DSC and this demonstrated that the incorporation of F-POSS did not affect the bulk matrix properties inherent of PFCB aryl ether polymers. This work demonstrated that optimized F-POSS PFCB aryl ether polymer blend formulations have potential use as hydro- and oleophobic materials for seals, fibers, and coatings.

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.

A difluorovinylene aromatic ether polymer (P1) incorporating periodic 5,5′-distyryl-2,2′-bipyridyl units as metal chelating chromophores was prepared by a transition metal-free step-growth polymerization. P1 displays strong ionochromic and ionoluminescent effects in response to transition metals. Although significant emission quenching is observed upon exposure to most transition metal ions, bathochromically shifted emission is observed upon addition of divalent d10 ions (Zn2+, Cd2+ and Hg2+). A selective 10-fold increase in integrated emission intensity is observed upon addition of Zn2+ to P1. The Zn2+-P1 metallopolymer acts as a ratiometric fluorescent indicator selective for fluoride anions, and the Cu2+-P1 metallopolymer exhibits a striking turn-on fluorescence response (>100-fold increase in integrated intensity) selective for cyanide and fluoride anions.

New fluorovinylene aromatic ether polymers, possessing dual reactivity, have been successfully prepared via the step-growth polymerization of commercial bis(trifluorovinyl) aromatic ethers and bisphenols.