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The recently discovered channel-shaped nanoporous ɛ crystalline form of syndiotactic polystyrene (s-PS) is generally obtained by a chloroform-induced recrystallization of samples exhibiting the helical γ crystalline form, followed by chloroform desorption in suitable conditions. This nanoporous ɛ crystalline form can be also obtained by crystallization of amorphous samples as induced by the same chloroform...
Nitrogen-doped carbon particles were produced using the hydrothermal carbonization of a nitrogen-containing carbohydrate, namely glucosamine, under mild temperature conditions (180 °C) followed by further calcination under a stream of inert gas at 750 °C. The resulting materials contain significant amounts of nitrogen doping within their structure, mainly as quaternary N involved in an aromatized/graphitized...
New poly(arylene ether)s with pendent trifluoromethyl groups were synthesized from 2,2′-bis(trifluoromethyl)-4,4′-dinitro-1,1′-biphenyl with several bisphenols. The nitro leaving group activated by the trifluoromethyl group at meta position was quantitatively displaced with phenolate ions, resulting in high molecular weight polymers. The quantum mechanical calculation of the energy state suggested...
The complex microstructures of bidisperse nanoparticles/diblock copolymer mixtures in dilute solutions have been investigated by a theoretical approach which combines the self-consistent field theory (SCFT) and the density functional theory (DFT). Special attention is payed to the role played by the block ratio and the interaction parameters between each component in the mixture. It is shown that...
This paper demonstrates synthesis of hyperbranched polymers (HTP and HTPOCH 3 ), containing triphenylamine moieties in main chain and thermally cross-linkable periphery or terminal vinyl groups, and application as hole-transporting layer (HTL) in multilayer light-emitting diodes. Absorption and photoluminescence (PL) spectroscopy, cyclic voltammetry (CV) and differential scanning calorimetry...
A unique rapid scanning rate differential scanning calorimeter is used to examine the differences in melt and cold crystallized poly (l-Lactide) (PLLA), a biodegradable semi-crystalline polymer. After isothermal melt and cold crystallization at various temperatures, both melt and cold crystallized PLLA are characterized by similar melting temperatures (T m ) and exhibit multiple melting behavior...
The present work introduces a new method for the characterization of morphology development and kinetics of nanoclay distribution in hydrogenated acrylonitrile butadiene rubber (HNBR)/natural rubber (NR) blends based on the measurement of electrical conductance during the mixing process. It was found that the online measurable electrical conductance of rubber–clay mixtures, which is originated from...
A facile approach to the fabrication of ultrathin polymer films on a flat or curved substrate is presented. Polymers with unsaturated pendant groups were spin-coated on a photoinitiator tethered surface, which was then photoirradiated and washed with a solvent. The obtained films were uniform, smooth (R a < 0.2 nm) and exhibited robustness toward solvents. The thickness of the films was...
Thermo Stimulated Current (TSC) combined with Dynamic Dielectric Spectroscopy (DDS) have been applied to the investigation of dielectric relaxation modes of an even–odd Polyamide PA 6,9. The correlation between results obtained by both methods allows us to describe precisely the molecular mobility. At high temperature, the various dielectric relaxation phenomena are separated by applying the dielectric...
The phase behavior of PEB/PES (poly(ethylene-co-styrene)/poly(ethylene-co-butene)) blend system was studied by time resolved laser light scattering with both wide angle and small angle laser light scattering. The phase separation kinetics show that the phase diagram of this system is a closed loop with both lower critical solution transition (LCST) and upper critical solution transition (UCST), which...
Polyelectrolyte multilayer microcapsules are important for a variety of potential applications, and represent a convenient system for studying properties of multilayer films. Recent work explored a post-treatment of such capsules by organic solvents, by reporting a softening. Here we show, that an addition of a very small amount of solvent (THF) to the phosphorus [G 3 (NH + Et ...
A series of novel organosoluble polyimides and copolyimides with a propeller-shaped triarylamine unit were prepared from diamine and various aromatic dianhydrides via direct polycondensation. All of the polymers possessed tough, flexible, and strong films with high molecular weights. The polyimide and copolyimide films revealed electrochromic characteristics, with a color change from pale yellowish...
Copolymerizations of propene with norbornene were carried out using a syndiotactic metallocene catalyst at low initial comonomer concentrations for different polymerization times. The influence of the norbornene concentration on the catalytic activity and on the resulting material properties has been analyzed. The copolymer molecular weight decreased drastically when small amounts of norbornene were...
The glass transition temperature and the crystallization behaviour of poly(ethylene terephthalate) PET ultra-thin layers (a few tens of nm) within multilayered PET/polycarbonate (PC) coextruded films are investigated as a function of layer thickness by means of calorimetric measurements. Results are discussed in terms of reduced thickness and interface effects. The appearance and evolution of lamellar...
A series of new monomers of 2, 5-bis [(3, 4, 5-trialkoxy benzyl) oxycarbonyl] styrene (denoted as M-tri-OC m H 2m+ 1 , m = 1, 2, 4, 6, 8, 10, 12, where m indicated the number of carbon atoms in the alkoxy group) were designed and synthesized. Then, their corresponding polymers P-tri-OC m H 2m+ 1 (m = 1, 2, 4, 6, 8, 10, 12) were synthesized by free...
Electroactive poly(amic acid), with oligoaniline in the main chain, was synthesized from macro-monomer of oligoaniline and p-phenylenediamine by oxidative coupling polymerization. The polymer characterization included Fourier-transform infrared spectra (FTIR), 1 H nuclear magnetic resonance spectra ( 1 H NMR) and gel permeation chromatography (GPC) as a determination of polymer structure,...
Multi-stimuli responsive poly(ether amine) (PEA) was successfully grafted on the planar silicon through a convenient and efficient way via “thiol-ene” click chemistry. The whole process for fabrication of PEA brush was carefully traced by XPS, AFM, ellipsometer and water contact angle (WCA). The results indicated that PEA brushes with different thickness can be obtained through both photochemical...
For the most part, ternary polymer blends demonstrate complete wetting behavior. Conceptually, this is the state where one of the components will always tend to completely separate the other two and from a thermodynamic viewpoint is described as the case where two of the three possible binary spreading coefficients are negative and the other is positive, as defined by Harkins spreading theory. This...
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