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A new conductive polyaniline derivative containing disulfide bonds, poly[bis(2-aminophenyloxy)disulfide] (PAPOD), has been proposed as a high energy-storage material. PAPOD has been synthesized using a moderate oxidant ferric chloride and characterized by elemental analysis, X-ray photoelectron spectroscopy (XPS), FT-IR, FT-Raman, and UV–vis spectroscopy. The cyclic voltammograms of this polymer show...
Conformationally restricted polyesters comprising alternating azobenzene and chiral binaphthylene main-chain units undergo photo-induced oscillations in optical rotatory power when stimulated with sequential intervals of ultraviolet and visible light exposure. The incorporation of flexible (oligo)ethylene oxide backbone segments into these constructs has resulted in a new family of materials having...
The copolymerization of diastereomeric pairs of N-propargylphosphonamidate monomers 1–3 ((1R,2S,5R)-HCCCH 2 NHP(O)R-O-menthyl, 1: R=CH 3 , 2: R=C 2 H 5 , 3: R=n-C 3 H 7 ) carrying P- and C-chiral centers was carried out with (nbd)Rh + [η 6 -C 6 H 5 B − (C 6 H 5 ) 3 ] as a catalyst in CHCl...
The 20/80 blends of polyamide 6 (PA6) and acrylonitrile–butadiene–styrene copolymer (ABS) in the presence of styrene–maleic anhydride copolymer (SMA) and multiwall carbon nanotubes (MWNT) were prepared using melt-mixing technique. Crystallization behavior of the PA6 phase in the blends was studied using DSC, WAXD and SAXS techniques. Blends' morphology was characterized by SEM. We observed fractionated...
A series of aliphatic acid esters of (2-hydroxypropyl) cellulose (C n PC) were synthesized via the esterification of aliphatic acid chloride and (2-hydroxypropyl) cellulose (HPC). The liquid crystalline (LC) phases and transitions were investigated using differential scanning calorimetry, wide-angle X-ray diffraction (WAXD), and polarized light microscope (PLM) techniques. This series of C...
Curing kinetics and mechanism of liquid lignin based epoxy resin (LEPL)–maleic anhydride (MA) system accelerated with benzyldimethylamine (BDMA) were studied by Fourier transform infrared (FTIR) spectroscopy and differential scanning calorimetry (DSC). In order to investigate the difference in the curing process, heating FTIR was used to study the change of the functional group. Complete consumption...
Polyimides are used as the outer layer of thermal control insulation blankets covering most of the external spacecraft surfaces that are exposed to space environment. The combined effect of ground simulated hypervelocity space debris impacts and atomic oxygen (AO) on the fracture of polyimide films was studied. A laser-driven flyer system was used to accelerate aluminum flyers to impact velocities...
Novel, segmented non-chain extended polyureas were synthesized. Soft segments (SS) were based on poly(tetramethylene glycol) (PTMO) (average molecular weight 1000 or 2000g/mol) and hard segments (HS) were based on a single molecule of a diisocyanate, which was either 1,6-hexamethylene diisocyanate (HDI), 1,4-phenylene diisocyanate (pPDI) or 1,4-trans-cyclohexyl diisocyanate (CHDI). An increase in...
Nonlinear optical response in various polyhydroxyalkanoates (PHAs) was investigated via second harmonic generation microscopy (SHGM). It was revealed that the second harmonic generation (SHG) efficiency depended on both the polymer chemical structure and the crystalline structure. Among the PHAs studied, the microbial polyesters, poly(R-3-hydroxybutyrate) (PHB) and poly(R-3-hydroxyvalerate) (PHV)...
Ultra-high molecular weight isotactic poly(1-butene) (UHMW-PB1) melt-grown crystal (MGC) films were drawn using the PIN drawing technique. Although the UHMW-PB1 MGC films had poor ductility in the crystalline state, they were ultradrawable in the molten state above the static melting temperature (T m ). The drawability of the MGC films was strongly influenced by the draw temperature, the sample...
The role of “epitaxy” of nucleating agent (NA) in nucleation mechanism of polymers was studied to formulate the nucleation rate (I) as a function of concentration of NA (C NA ) in mixture of polymer and NA and lateral size of a NA crystal (a NA ), I∝C NA /a NA . It is proved that the epitaxy of NA controls nucleation mechanism by confirming above formula experimentally...
A new series of sulfide-containing polyfluorene homopolymers and copolymers (PFS, PF1, PF3 and PF4) comprising 9,9-di[11-(decylsulfanyl)undecyl] fluorene, 9,9-dihexylfluorene, triphenylamine or benzothiadiazole moieties were synthesized by Ni(0)-mediated Yamamoto-coupling and palladium-catalyzed Suzuki polymerizations. Three other polyfluorenes (PF2, PF5 and PFC6) without sulfur atom in the alkyl side...
Diglycidyl ether of bisphenol A (DGEBA) is one of the most widely used epoxy resins for many industrial applications, including cryogenic engineering. In this paper, diethyl toluene diamine (DETD) cured DGEBA epoxy resin has been modified by two flexible diamines (D-230 and D-400). The cryogenic mechanical behaviors of the modified epoxy resins are studied in terms of the tensile properties and Charpy...
Polymer–polymer interactions in majority of engineering polymers are difficult to measure experimentally, since many polymers are usually insoluble in solvents, have high glass transition temperatures, and are sometimes poorly characterized. Therefore, applying molecular modeling strategies would be helpful in such situations in order to provide useful information, which would be difficult to obtain...
The functionalization of a styrene/butadiene (20/80) random copolymer (SBR) is performed by radical-mediated addition of l-cysteine derivatives to the macromolecules' double bonds. The reaction carried out in solution and in the melt leads to SBR chain bearing amino and carboxylate functionalities through thiol addition to the vinyl double bonds of the 1,2-butadiene units with anti-Markovnikov regioselectivity...
Free radical copolymerization reaction of vinyl acetate (VA) and methyl acrylate (MA) in solution of benzene-d 6 using benzoyl peroxide (BPO) as the initiator was studied with on-line 1 H NMR kinetic experiments at 60°C. It was observed that composition drifts in the comonomer mixture with reaction progress is significant. Hence, the monomer reactivity ratios of VA/MA system could...
Aliphatic poly(alkylene dithiocarbonate)s are an interesting class of potentially biodegradable and biocompatible materials in analogy with their homologous poly(alkylene carbonate)s. In this paper, the properties of poly(hexamethylene dithiocarbonate) (SSR6) are compared to those of poly(hexamethylene carbonate) (HMC) in order to study the effect of the substitution of oxygen atoms with sulphur atoms...
Novel self-assembled micro/nanostructured polyaniline–clay nanocomposite (PANICN) materials were prepared by in situ intercalative emulsion polymerization of aniline in aqueous dispersion of clay using functionalized amphiphilic dopant, 3-pentadecyl phenyl phosphoric acid (PDPPA) derived from renewable resource. The structural effect of PDPPA on the morphology, electrical conductivity and phase transition...
In the present article the swelling behavior of copolymer microgel particles made of poly(N-isopropylacrylamide)-co-vinylacetic acid using dynamic light scattering (DLS), neutron scattering, and in situ atomic force microscopy (AFM) for various copolymerized amounts of vinylacetic acid (VA) (up to 2.5mol%) under slightly acidic conditions is studied. The transition temperature of these microgel particles...
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