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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-shifts compared with polymer solutions presumably attributable to aggregation in the solid state. Solution quantum yields of the polymers were comparable to those reported for the single chromophores used in this study. [ABSTRACT FROM AUTHOR]

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 CHCl3using polystyrene as standard) determined by gel permeation chromatography (GPC). Thermal properties of POSS PFCB aryl ether copolymers were evaluated by differential scanning calorimetry (DSC) and thermal gravimetric analysis (TGA). Transmission electron microscope (TEM) analysis of spin cast optically transparent, flexible POSS PFCB aryl ether copolymer films revealed the presence of 5−20 nm-sized POSS agglomerates. Optical profilometer analysis of spin and drop cast film surfaces exhibited a modest increase in surface roughness of POSS PFCB aryl ether copolymers as compared to PFCB aryl ether homopolymers without POSS inclusion. The POSS copolymers exhibited a modest increase in hydrophobicity as measured by static water contact angle analysis. Synthesis, characterization, thermal analysis, and unique surface features of POSS PFCB aryl ether copolymers are discussed. [ABSTRACT FROM AUTHOR]

Versatile intermediates 4-bromo(trifluorovinyloxy)benzene or 4-trifluorovinyloxyphenylboronic acid pinacol ester undergo a one step Suzuki coupling reaction with commercial aryl diboronic acids or aryl dibromides and afforded three new aryltrifluorovinylether chromophore monomers. The structures of these monomers were confirmed by 1H, 19F, and 13C NMR spectroscopy and elemental (C, H, and N) combustion analysis. The monomers were readily polymerized via thermal 2 2 cyclopolymerization to form chromophore containing PFCB polymers with high molecular weights (Mn 16 700−22 000), superb thermal stability Td> 450 °C, and excellent processability. Photoluminescence studies reveal that the fluorinated ether linkage has no effect on lumiphore emission wavelength or solution quantum yields. Copolymerization affords a facile route to tailored emission from a linear polymeric system that includes a broad range of the visible spectrum. The properties of these polymers were analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis (TGA), gel permeation chromatography (GPC), and absorbance and photoluminescence spectroscopy. [ABSTRACT FROM AUTHOR]

A novel approach to property enhancement of poly(l-lactic acid) (PLLA) through the use of perfluoropolyether (PFPE) enchainment is described. Segmented copolymers (FluoroPLA) exhibit tailored surface properties with reasonably high molecular weights and low polydispersities compared to PLLA alone using standard ring-opening polymerization procedures in the presence of tin catalysts. Low loadings of PFPE content (ca. 1−5 wt %) decreases surface energies compared to PLLA from 35 to 38 to 15−18 mN/m2, similar to values reported for poly(tetrafluoroethylene). Ultimate strain studies of FluoroPLA fibers and films have shown a dramatic increase (>300% elongation) over PLLA. This new class of polymer may further expand the use of renewable resources in a variety of applications such as flame retardants, chemical resistant fibers and/or fabrics with tailorable surface energies and wetting properties. [ABSTRACT FROM AUTHOR]

High-pressure phase behavior data reported here demonstrate the nuanced impact fluorine exerts on polymer solubility in supercritical fluid solvents. Copolymers are used that contain a perfluorocyclobutyl ether group with varying amounts of bis-aryl isopropylidene (6H) or bis-aryl hexafluoroisopropylidene (6F). Surprisingly, it takes at least 2000 bar and 190 °C to dissolve the 6Hhomopolymer in CO2even though every repeat group has ∼15 mol % fluorine and two ether oxygens, both of which enhance polymer solubility in CO2. The copolymer cloud-point curves in CO2monotonically shift significantly to lower temperatures and pressures as the 6Fcontent is increased from 0 to 100%. This shift is ascribed to the decrease in long-range, chain−chain interactions due to poor packing of the 6F-rich chains, to the increase in solvent accessible surface area of fluorinated groups, and to the increase in the fractional free volume (FFV) of 6F-rich chains. The cloud-point curves in propane also initially shift to lower temperatures and pressures with increasing 6Fcontent, but the 6Fhomopolymer and 6Hhomopolymer curves cross one another so that the 6Hhomopolymers are more soluble at low temperatures while 6Fhomopolymers are more soluble at high temperatures. The reversal in propane solubility behavior with increasing 6Fcontent and temperature results from a delicate balance between repulsive fluorine−hydrocarbon interactions that do not favor copolymer solubility and reduced long-range, chain−chain interactions and increased copolymer FFV that both favor copolymer solubility. The cloud-point data also show that for both CO2and propane the impact of 6Fcontent is greater than the impact of weight-average molecular weight in the range 15−93 kg/mol, where molecular weight is expected to have a large impact. [ABSTRACT FROM AUTHOR]

This study focuses on the preparation, polymerization, characterization, and optical properties of a new bis‐(4‐trifluoromethanesulfonyloxyphenyl)phenylamine monomer. This is the first nitrogen‐containing monomer having nitrogen atoms as bridges between phenyl rings, and it was synthesized in three steps. The polymerization was carried out through the Ni(0)‐catalyzed homocoupling reaction of the bis‐(4‐trifluoromethanesulfonyloxyphenyl)phenylamine compound. The resulting polymer, polybis(paraphenyl)phenylamine, emitted an intense blue color (where λ = 415 nm) upon irradiation by ultraviolet light. The photoluminescence quantum yield was found to be 36% with a long excited‐state lifetime of 3.3 ns. Electrical conductivity data for an HCl‐doped film of the polymer were also examined. This novel polymer is of interest as an organic emitting material for electroluminescent devices. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 45: 1860–1867, 2007 [ABSTRACT FROM AUTHOR]

In situ copolyesters containing polylactide (PLA) and polyhydroxyalkanoate (PHA) segments were obtained via ring-opening polymerization of l-lactide using PHA as a macroinitiator with stannous octoate as catalyst. Incorporation of PHA (20 wt %) into PLA affords a novel copolymer with Mnvalues ranging from 25 to 50 KDa and low polydispersities of 1.8−2.3. DSC analysis of the copolymer indicates well-defined crystallization and melting transitions different from the homopolymers and corresponding blend. The polymers were characterized by FT-IR, GPC, DSC, optical microscopy, NMR, and TGA. The results show successful reactivity of PHA as a macroinitiator for the ring-opening polymerization of lactide. [ABSTRACT FROM AUTHOR]

Multilayer fullerenes (carbon nano-onions, CNOs) represent a largely unexplored carbon allotrope due to their inherent insolubility. Expectations are that the properties of these nano-onions will be unique and potentially useful, as has been the case with the fullerenes and carbon nanotubes (CNTs). CNOs show diminished chemical reactivity; however, the established thermal diradical formation and reactivity of bis-o-diynyl arene (BODA) monomers afforded direct functionalization, solution processing, and de-functionalization of CNOs; and the first example of a radical addition of a conjugated polymer to CNOs. The functionalized and soluble CNOs were characterized by TEM, GPC, TGA, Raman spectroscopy, and XPS. A CNO defunctionalization method using oxidative TGA is also presented. [ABSTRACT FROM AUTHOR]

New fluorinated polyhedral oligomeric silsesquioxane (F-POSS) structures possessing a high degree of hydrophobicity have been prepared via a facile corner-capping methodology. [ABSTRACT FROM AUTHOR]