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11.
New polythioesters by interfacial polycondensation of 4,4′-di(mercaptomethyl) benzophenone with oxalyl, succinyl, adipoyl, suberoyl, and sebacoyl chlorides were obtained. To determine the optimal conditions for interfacial polycondensation the influence of the following factors on yield and value of reduced viscosity were studied: type of organic phase, the quantitative ratio of aqueous and organic phase, concentration of hydrogen chloride acceptor, molar ratio of reagents, temperature of reaction, rate of acid chloride addition, and contribution of catalyst and emulsifier. A thorough examination was carried out only for polycondensation of dithiol with adipoly and sebacoyl chlorides. The structure of all polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition and initial intensive decomposition temperature were defined from the curves of thermogravimetric analysis. Some mechanical and electrical properties of the polythioesters obtained from 4,4′-di(mercaptomethyl)benzophenone and adipoyl and sebacoyl chlorides were determined. The molecular weight was not measured because of the low solubility of the obtained polythioesters.  相似文献   
12.
Synthesis and characterization of new type photoluminescent, bulk copolymers of 2,7‐(2‐hydroxy‐3‐methacryloyloxypropoxy)naphthalene (2,7‐NAF.DM) with different vinyl comonomers (methyl methacrylate, 2‐hydroxyethyl methacrylate, butyl acrylate, divinylbenzene, styrene and N‐vinyl‐2‐pyrrolidone) are presented. The chemical structure of 2,7‐NAF.DM was confirmed by NMR, GC‐MS and elemental analysis. The copolymers were characterized by ATR and thermal (differential scanning calorimetry) analyses. Their luminescent properties were studied in terms of quantum efficiency (Φabs), which was shown to change in the range of 50–90% depending on the type of comonomer. It was found that the green‐emitting species in these polymers can be excited directly by low‐energy (400–520 nm) photoirradiation. These materials can be applied in the liquid or solid states in the form of powders, films or monoliths. Copyright © 2014 John Wiley & Sons, Ltd.  相似文献   
13.

The aim of this study was the synthesis of three different epoxy compounds based on naphthalene-2,7-diol (2,7-NAF.EP, 2,7-NAF.WEP, 2,7-NAF.P.EP) and then their cross-linking by triethylenetetramine (TETA). All epoxides were prepared by the reaction of naphthalene-2,7-diol with epichlorohydrin but under different conditions and with other catalysts. The structures of the obtained compounds before and after the cross-linking reactions were confirmed by the attenuated total reflectance Fourier transform infrared spectroscopy (ATR/FT-IR). The ATR/FT-IR spectra of cross-linked compounds show disappearance of the C–O–C bands (about 915 cm?1) derived from the epoxy groups. DSC and TG/DTG measurements indicated that the obtained materials possess good thermal resistance; they are stable up to about 250 °C. The hardness of the cross-linked products was determined using the Shore D method. The highest value of hardness was obtained for the 2,7-NAF.EP-POL. Additionally, the UV–Vis absorption spectra of the obtained polymers were registered and evaluated.

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14.
15.
New polythioesters of naphthalene derivatives by polycondensation of 1,4-di(mercaptomethyl)-naphthalene, 1,5-di(mercaptomethyl)naphthalene, as well as their mixture with adipoyl and sebacoyl chlorides have been obtained. Low-temperature and high-temperature solution polycondensation as well as interfacial polycondensation have been used. Interfacial polycondensation proved to be the most useful. To define the optimal conditions of interfacial polycondensation, the following factors influencing the process have been studied: ratio of aqueous to organic phase, concentration of hydrochloride acceptor, temperature of reaction and rate of addition of acid chloride, contribution of emulsifier and catalyst. Yield for all reaction products and reduced viscosity have been found. The structure of polythioesters of high-value viscosity and good yield was determined from elementary analysis, infrared spectra, x-ray, and thermogravimetric analysis. Some mechanical and electrical properties of the polythioesters obtained from the mixture of 1,4- and 1,5-di(mercaptomethyl)naphthalene have been studied after pressing in increased temperature. The molecular weight was not determined because of very low solubility.  相似文献   
16.
New thermoplastic nonsegmented thiopolyurethanes were synthesized from the new low‐melting aliphatic‐aromatic thiodiols bis[4‐(2‐hydroxyethyl)thiomethylphenyl]methane, bis[4‐(3‐hydroxypropyl)thiomethylphenyl]methane, and bis[4‐(6‐hydroxyhexyl)thiomethylphenyl]methane and hexamethylene diisocyanate both by melt and solution polyaddition with dibutyltin dilaurate as a catalyst. All the thiodiols were prepared with high yields by the condensation reaction of bis(4‐mercaptomethylphenyl)methane with 2‐chloroethanol, 3‐chloro‐1‐propanol, or 6‐chloro‐1‐hexanol. The hard‐segment‐type polyurethanes obtained were plastic materials with partially crystalline structures. Polymerization in solution produced products with higher molecular weights (ηred = 0.97–1.24 dL/g) than polymerization in melt (ηred = 0.44–1.05 dL/g). The structures of all the polyurethanes were determined with elemental analysis, Fourier transform infrared, and X‐ray diffraction analysis. Thermal properties of the polymers obtained in solution were examined by differential scanning calorimetry and thermogravimetric analysis. Shore A/D hardness and tensile properties for all the polyurethanes were also determined. Of the two kinds, the polyurethanes obtained in solution possessed better tensile properties and showed yield stress (tensile strength) in a range of 27.8–30.0 MPa at an elongation of 17.4–25.1%. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1767–1773, 2000  相似文献   
17.
The results of the studies concerning photo- and thermally initiated copolymerization of bis[4(2-hydroxy-3-methacryloyloxypropoxy)phenyl]sulfide (BES-DM) with N-vinyl-2-pyrrolidone (NVP) and thermo-mechanical properties of resulting compositions are presented. BES-DM was obtained in the two-step reaction. In the first step, the epoxy resin was synthesized. It was obtained in the reaction of bis(4-hydroxyphenyl)sulfide with 2-(chloromethyl)oxirane. In the second step, esterification of the obtained diglycidyl ether was carried out with the use of methacrylic acid. New copolymers with different degrees of crosslinking were obtained. The study describes the effect of crosslinking degree and the method of polymerization initiation on the properties of the new compositions. Density, viscosity, glass temperature, Young’s modulus, hardness, tensile strength were determined before and after curing for the compositions of BES-DM and NVP. Moreover, the dynamic-mechanical and thermal properties for the chosen samples of copolymers were studied.  相似文献   
18.
The purpose of this paper is to show the possibility of introducing a non-symmetric transition probability in quantum mechanics, starting from the axiomatic basis of the theory known as the “quantum logic approach”. The quantum-mechanical postulates are later reformulated in the language of the transition probability and the operations (filtering procedures) transforming pure states of a physical system into themselves, ans some advantages of this formulation are shown consisting mainly in resolving the old troubles connected with quantum logics (e.g., the questions of the complete lattice structure of the logic, atomicity, the validity of the covering law).As a consequence of the axioms assumed, the representation theorem for the logic of proposition is deduced.  相似文献   
19.
The paper contains an axiomatic formulation of statistical physical theories, which may be considered as an alternative to the famous Mackey's approach. In contrast to the Mackey's axiomatics, in which the so-called propositional logic appears as a basic object, our approach takes the partially ordered vector space spanned by states of a physical system as a starting point. The propositional logic appears then as a set of positive functionals on this space.  相似文献   
20.
Syntheses of the new photoluminescent copolymers: 2,7-(2-hydroxy-3-methacryloyloxypropoxy)naphthalene with N-vinyl-2-pyrrolidone (NVP) are presented. The obtained compound was copolymerised with different ratios of active diluent (NVP). Thermo- and photo-polymerisations of the compositions with use of the initiators: α,α′-azoiso-bis-butyronitrile and 2,2-dimethoxy-2-phenyl-acetophenone were carried out. The following properties were determined: density, polymerisation shrinkage, glass transition temperature, Young’s modulus, hardness and tensile strength. Moreover, the dynamic-mechanical, thermal and photoluminescent properties were studied. These materials may have potential use as luminophores and coatings filtering harmful UV radiation.  相似文献   
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