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1.
Several new polyesters containing sulfur in the main chain were obtained by melt polycondensation of diphenylmethane-4,4′-di(methylthioacetic acid) with ethanediol, 1,3-propane diol, 1,4-butanediol, 1,5-pentenediol, 1,6-hexanediol, 1,2-propanediol, and 2,2′-oxydiethanol. The structure of all polyesters was determined from elemental analysis and infrared (IR) spectra. Yield, reduced viscosity, molecular weight, and softening temperature for reaction products have been found. Initial decomposition and initial intensive decomposition temperature were defined from the curves of thermogravimetric analysis. 相似文献
2.
Beata Podkościelna 《应用聚合物科学杂志》2011,120(5):3020-3026
Synthesis, copolymerization, and physicochemical properties of new, of different degrees of crosslinker tetrafunctional bis[4(2‐hydroxy‐3‐methacryloyloxypropoxy)phenyl]sulfide and glycidyl methacrylate copolymers are presented. The monomers were used for the synthesis of porous microspheres in the presence of pore‐forming diluents, decan‐1‐ol, and toluene. Influence of diluents composition on their porous structures was studied. Porous structure of the obtained microspheres in dry (from nitrogen adsorption–desorption measurements) states was studied. Their chemical structures were studied by the use of Fourier transform infrared. The number of epoxy groups of the obtained copolymers, their thermal properties (thermogravimetric analysis), and swelling characteristics in 10 solvents of different chemical nature were examined. Selected copolymers were modified by amines in the epoxide ring‐opening reaction. © 2011 Wiley Periodicals, Inc. J Appl Polym Sci, 2011 相似文献
3.
New polythioesters by interfacial polycondensation of 1,4-dimercaptomethyl–tetramethylbenzene with oxalyl, succinyl, adipoyl, suberoyl, sebacoyl, and isomeric phthaloyl dichlorides were obtained. To define 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, concentration of hydrogen chloride acceptor, the quantitative ratio of aqueous to organic phase, molar ratio of reagents rate of acid chloride addition, contribution of benzyltriethylammonium chloride as a catalyst, and the temperature of the reaction. Thorough studies were carried out only for polycondensation of the dithiol with adipoyl, sebacoyl, and isophthaloyl chlorides. The structure of polythioesters obtained under the model conditions was determined by elementary analysis and infrared spectra. Initial decomposition temperature, mass loss in percentage at the same temperature, maximum rate of decomposition, and mass loss percentage at 100–400°C were defined from the curves of thermogravimetric analysis. Chemical resistance of the polythioesters was determined by treatment with some organic solvents, mineral acids (concentrated and 10%) and sodium hydroxide (10% and 50%). The molecular weight was not measured because of the low solubility of the polythioesters. 相似文献
4.
The synthesis of a new aliphatic–aromatic polythioesters obtained by polycondensation of 4,5-di(mercaptomethyl)–1,2-dimethylbenzene,4,6-di(mercaptomethyl)–1,3-dimethylbenzene and 2,5-di(mercaptomethyl)–1,4-dimethylbenzene with adipoyl and sebacoyl chloride is described. To define the optimal condition of the process, the polythioester from 2,5-di(mercaptomethyl)–1,4-dimethylbenzene and sebacoyl chloride was chosen as a model system and obtained by interfacial polycondensation as well as by low- and high-temperature solution polycondensation. To determine the optimal conditions for polycondensation the following parameters have been studied: kind of organic solvent, concentration of reagents, temperature and time of reaction and, in the case of interfacial polycondensation additional, ratio of aqueous to organic phase, kind and concentration of hydrochloride acceptor, and kind and concentration of catalyst were taken into consideration. The quality of the obtained polycondensates was estimated on the basis of values of the reduced viscosity and yield. The structure of the aliphatic–aromatic polythioesters was determined from elementary analysis, infrared spectra, and X-ray analysis. Some thermal, mechanical, electrical, and chemical properties as well as molecular weights of obtained polycondensates have been determined. 相似文献
5.
Synthesis of highly crosslinked methacrylate copolymers of in form of microspheres is presented. They are prepared from tetrafunctional methacrylate derivative of bis(4‐hydroxyphenyl)sulfide, bis[4‐(2‐hydroxy‐3‐methacryloyloxypropoxy)phenyl]sulfide (BES‐DM), and divinylbenzene (DVB). In chemical structure of these copolymers exhibit hydroxyl and ester groups of hydrophilic nature. Additionally, copolymer contains sulfur atoms coming from BES‐DM monomer. Porous structure of the copolymers in the dry and wet state was studied. Microspheres possessing the largest pore volume and specific surface area were subjected to chromatographic investigations. The results show that polar functional groups existing in the chemical structure of the studied microspheres have influence on reversed‐phase HPLC retention mechanism. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2009 相似文献
6.
New polythioesters were obtained by interfacial polycondensation of 4,4′-dimercaptobiphenyl with selected aliphatic and isomeric phthaloyl dichlorides. To determine the optimum polycondensation conditions, the influence of the following factors on reduced viscosity and yield were studied: type of organic phase, concentration of hydrogen chloride acceptor, type of catalyst, reaction temperature and rate of acid dichloride addition. A thorough examination was carried out only for the polycondensation of dithiol with isophthaloyl dichloride chosen as a model system. The structures of polythioesters were determined by elemental analysis, X-ray and infrared spectra. The temperature of initial decomposition, the percentage of its mass loss, and temperature of the fastest decomposition process were determined from curves of differential and thermogravimetric analysis. Some physicochemical, mechanical and electrical properties were determined. The molecular weights were not measured because of the low solubility of the obtained polythioesters. 相似文献
7.
New polythioesters were synthesized by interfacial polycondensation of 4,4'-bis(mercaptomethyl)biphenyl with selected aliphatic and isomeric phthaloyl dichlorides. To determine optimum polycondensation conditions, the influence of the following factors on reduced viscosity and yield were studied: type of organic phase, concentration of reagents, aqueous/organic phase ratio, type and concentration of hydrogen chloride acceptor, rate of acid chloride addition, reaction temperature and reaction time. A thorough examination was carried out only for the polycondensation of dithiol with adipoyl and isophthaloyl dichlorides chosen as a model system. The structures of polythioesters were confirmed by elemental analysis, X-ray analysis and infrared spectroscopy. The temperature of initial decomposition, the percentage of its mass loss, and temperature of the fastest decomposition process from curves of differential and thermogravimetric analysis were determined. Some physicochemical, mechanical and electrical properties were determined. The molecular weights were not measured because of the low solubility of the obtained polythioesters. 相似文献
8.
New polythioesters were obtained by interfacial polycondensation of bis(4-mercaptophenyl)ether with phthaloyl, isophthaloyl, and terephthaloyl chlorides. To determine the optimal conditions for interfacial polycondensation, the influence of the following factors on yield and value of reduced viscosity were studied: organic phase, 100% excess of sodium hydroxide, contribution of benzyltriethylammonium chloride as a catalyst, and the temperature of the reaction. A thorough examination of the process was carried out only for polycondensation of dithiol with phthaloyl chloride. Yield of all reaction products as well as reduced viscosity of only polythioesters from dithiol and phthaloyl chloride were found because these were the ones which were soluble in tetrachloroethane. The structure of all polythioesters was determined by elemental analysis and infrared spectra. Initial decomposition and initial intensive decomposition temperature were defined by the curves of thermogravimetric analysis. Some mechanical and electrical properties of polythioesters were determined. 相似文献
9.
A few new thiodicarboxylic acids and thiodiols were obtained by condensation reaction of 4,4′-bis(mercaptomethyl)benzophenone (BMMB) with some halogen acids or halogen alcohols, respectively, in aqueous sodium hydroxide solution. By melt polycondensation of one of these acids, i.e. benzophenone-4,4′-bis-(methylthioacetic acid) (BBMTAA) with 1,5-pentanediol, a new linear polyester was obtained, and by melt polyaddition of one of these diols, i. e. benzophenone-4,4′-bis(methylthiohexanol) (BBMTH) with hexamethylene diisocyanate (HDI) a new linear polyurethane was obtained. The structures of monomers and polymers were confirmed by elemental analysis and FT-IR and 1H NMR spectroscopy. The polymers were studied to describe their physicochemical, thermal and mechanical properties. 相似文献
10.
New thioether glycidyl resins by condensation of bis(4-mercaptophenyl)sulfide or bis(4-mercaptophenyl)sulfone with epichlorohydrin were obtained by heterophase alkaline condensation in aqueous and isopropanol medium using sodium hydroxide. The detailed studies on their structures from elemental analysis and IR and 1H-NMR spectra, physical and chemical properties, and curing conditions are presented. Thioether glycidyl resins compositions were also prepared using curatives typical for epoxy resins and after curing they were characterized from derivatographic, thermomechanical, and mechanical studies. 相似文献