Morphology and mechanical properties of polymer-inorganic nanocomposite containing triple chain fibrous Na-Mg hydrosilicate

Russian Journal of General Chemistry - A polymer-inorganic nanocomposite of fibrous Na-Mg triple chain hydrosilicate and polyamidoimide based on 4-chloroformyl-(N-p-chloroformylphenyl)phthalimide...     

Interrelation between the structural and transport properties of pervaporation membranes with diffusion layers based on poly-γ-benzyl-L-glutamate

The interrelation between the transport properties of pervaporation membranes (used to separate toluene-n-heptane mixtures) and the structure of poly-γ-benzyl-L-glutamate diffusion layers has been studied. The decrease in the membrane selectivity while increasing the flux at the transition from 3 to 50 wt % toluene in the mixture under separation is accompanied by a change in the ordered structure of poly-γ-benzyl-L-glutamate structure without variation in the α-helical conformation of the polypeptide chain.     

Pervaporation Membranes for Separating Mixtures of Methanol and Methyl tert-Butyl Ether

Transport characteristics of new types of bi- and multilayer composite polymer pervaporation membranes and asymmetrical membranes in separating mixtures of methanol and methyl tert-butyl ether were studied. The principles of design of the membranes and their mass-exchange characteristics are treated in terms of the Henis-Tripodi resistance model.     

Reactions of (4E)-3-Arylamino-4-(hydroxyimino)naphthalen-1(4H)-ones and (4E)-2-[Arylamino(alkylamino)]-4-(hydroxyimino)naphthalen-1(4H)-ones with 2,2-Dihydroxyindane-1,3-dione

Russian Journal of Organic Chemistry - The reactions of 3-arylamino-1,4-naphthoquinone-4-oximes with 2,2-dihydroxyindane-1,3-dione proceed without involving the oxime group and lead to...     

Light-sensitive chalcone-containing poly(amido imides)

Soluble poly(amido imides) and copoly(amido imides) containing main-and side-chain chromophore chalcone groups have been synthesized. Thermo-and photocrosslinking of polymer chains in films under UV irradiation have been studied. The mechanical properties, dielectric behavior, and photosensitivity and photoconductivity characteristics of the polymers have been investigated.     

Synthesis and properties of glycidyl methacrylate copolymers with side chromophore groups

A number of styrylquinoline chromophores with carboxyl groups have been prepared through the interaction of 2-methylcinchonic acid with aromatic aldehydes of various chemical structures. The copolymer of glycidyl methacrylate and methyl methacrylate carrying side epoxide groups has been synthesized, and the chemical modification of the copolymer with the above chromophores has been performed. The thermal, spectral, and nonlinear optical properties of the chromophores and modified polymers have been studied.     

Structure, morphology, and thermal properties of nanocomposites based on polyamido imide and hydrosilicate nanotubes

New nanocomposites based on heat-resistant poly[(diphenyl oxide)amido-N-phenylphthalimide] with Mg₃Si₂O₅(OH)₄ hydrosilicate nanoparticles of tubular structure were prepared. The structure, morphology, and thermal properties of the nanocomposites were studied in relation to the content of hydrosilicate nanotubes.     

Photosensitivity of polyimides and polyquinazolones based on aromatic and heteroaromatic diamines

Soluble polyimides containing triphenylamine residues as substituents at the imide nitrogen atom and polyquinazolones with diphenyl oxide, diphenylpropane, benzimidazole, benzoxazole, benzothiazole, oxadiazole, and triphenylamine moieties in the diamine component of the repeating unit have been synthesized. The spectroscopic study of polyquinazolones indicates their capability for donor-acceptor interactions. Emission bands of the polymers are of the exciplex nature. The photogeneration of current carriers in the polymers under study has been examined by the method of surface potential photoinduced decay. It has been shown that the intrinsic photosenitivity of polyquinazolones is nearly the same as (or somewhat higher than) that of the corresponding polyimides, but the former polymers are characterized by a less efficient spectral sensitization by dyes and donor-acceptor additives.     

Relaxation processes in an aromatic polyamide-imide and composites on its basis with hydrosilicate nanoparticles

Features of the relaxation behavior of an aromatic polyamide-imide and a composite with nanotubes of magnesium silicate with the structure of chrysotile have been studied by dynamic mechanical analysis, dielectric spectroscopy, and differential scanning calorimetry. Two secondary relaxation (β₁ and β₂) transitions have been found, the activation energies of these processes have been determined, and the solvent effect on the cooperativeness degree has been studied. Changes in the value of the apparent activation energy of the β₁-process caused by the subsequent heating of polymeric and composite samples have been analyzed according to the Starkweather procedure. It has been shown that, as the solvent is released from the polyamide-imide film, the polymer exhibits increasing local mobility, which are predetermined by the structure of the molecular unit. Using the GAMESS software, we have assumed the most probable dimer conformations that correspond to two repeating units of the polyamide-imide molecule.     

New composite materials based on polyvinylpyrrolidone and poly(diphenyl oxide amido-<Emphasis Type="Italic">N</Emphasis>-phenylphthalimide)

With the use of X-ray diffraction analysis, differential scanning calorimetry, dynamic mechanical analysis, and ATR FTIR spectroscopy, the structures and mechanical and thermophysical properties of composite films of various compositions obtained on the basis of polyvinylpyrrolidone and poly(diphenyl oxide amido-N-phenylphthalimide) are investigated. At all component ratios, these polymers form a complex via a system of hydrogen bonds during the formation of composites from solution. The best compatibility of blend components is attained at a polymer ratio of 1: 1, at which individual phases of initial components are absent. The temperatures of glass transition and of other thermal transitions of the samples are determined. Structural changes occurring in the films before and after pervaporation are studied. The considered membranes may show promise for the separation of liquids only in the case of the predominant formation of an interpolymer complex stable during the transport of penetrates of various polarities, such as cyclohexane or water, across the membrane.