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1.
L. J. Mathias C. G. Overberger 《Journal of polymer science. Part A, Polymer chemistry》1979,17(5):1287-1297
Aromatic polymers containing formamidine groups in the polymer backbone were obtained from aromatic diamines in high yields with α,α-dichloromethyl ether and triethylorthoformate. The latter was the reagent of choice. Soluble, high-molecular-weight products were obtained with m-phenylene diamine and 4,4′ bis(aminophenyl)methane. These polymers were characterized by viscosity, microanalysis, and nuclear magnetic resonance and infrared spectroscopy. Generally, insoluble products were obtained from p-phenylene diamine and 2,6-diaminotoluene, although small amounts of dimethylsulfoxide (DMSO)-soluble fractions could be extracted and examined by NMR spectroscopy. IR analysis of the insoluble fractions confirmed formation of polymers with the formamidine-containing structures. The synthetic procedures developed here make readily available this new class of aromatic polymers. 相似文献
2.
Yoshio Imai Mitsuru Ueda Takashi Iizawa 《Journal of polymer science. Part A, Polymer chemistry》1979,17(5):1483-1491
Wholly aromatic polysulfonamides of high molecular weight were prepared by the solution poly-condensation of aromatic disulfonyl chlorides with aromatic diamines in tetramethylene sulfone and substituted pyridines as the acid acceptor. Polysulfonamides with inherent viscosities as high as 1.2 were readily obtained by initiating polycondensation at a temperature of 5–10°C to control the side reactions. The polycondensation was fairly fast and was completed in 10 min at 60°C. All the aromatic polysulfonamides dissolved in a wide range of solvents, including acetone and tetrahydrofuran. These polymers were less thermally stable than the corresponding aromatic polyamides. 相似文献
3.
Yoshio Imai Mitsuru Ueda Takashi Iizawa Shuichi Kudo 《Journal of polymer science. Part A, Polymer chemistry》1979,17(9):2929-2933
Solution polycondensations of aromatic disulfonyl bromides with diamines in tetramethylene sulfone at room temperature by the use of organic or inorganic acid acceptors yielded polysulfonamides with moderately high molecular weights. Preferred acid acceptors were 2-methylpyridine and propylene oxide and lead oxide. The high activity of lead oxide was discussed in relation to the principle of hard and soft acid and bases. 相似文献
4.
Kazuto Inoue Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1995,33(14):2291-2296
New aromatic diamines containing phenyl-pendant thiazole units were synthesized in three steps starting from p-nitrobenzyl phenyl ketone. Novel aromatic polyamides containing phenyl-pendant thiazole units were prepared by the low-temperature solution polyconden-sation of 1,4- (or 1.3-) bis[5-(p-aminophenyl)-4-phenyl-2-thiazolyl] benzene with various aromatic dicarboxylic acid chlorides in N,N-dimethylacetamide. High molecular weight polyamides having inherent viscosities of 0.5–3.0 dL/g were obtained quantitatively. The polythiazole-amides with m-phenylene, 4,4′-oxydiphenylene, and 4,4′-sulfonyldiphenylene units were soluble in N-methyl-2-pyrrolidone, N,N-dimethylacetamide, and pyridine, and gave transparent flexible films by casting from the solutions. These organic solvent-soluble polyamides displayed prominent glass transition temperatures (Tg) between 257 and 325°C. On the other hand, the polythiazole-amides with p-phenylene and 4,4′-biphenylene units were insoluble in most organic solvents, and had no observed Tg. All the polythiazole-amides started to decompose at about 400°C with 10% weight loss being recorded at 450–525°C in air. © 1995 John Wiley & Sons, Inc. 相似文献
5.
Richard A. Brand Maria Bruma Raymond Kellman C. S. Marvel 《Journal of polymer science. Part A, Polymer chemistry》1978,16(9):2275-2284
Three oligomeric benzimidazoles have been prepared by the oxidative cyclization of the corresponding polyamidines. These materials are high melting and are soluble in solvents like dimethylformamide. They exhibit inherent viscosities of 0.20–0.25 in DMF at 0.5g/100 ml. Several model compounds have also been prepared to show the feasibility and scope of the oxidative cyclization reaction. 相似文献
6.
Two diamines were synthesized as new aromatic monomers. A series of novel aromatic polyamides (aramids) were also synthesized by direct and indirect polycondensation of these diamines with various aromatic dicarboxylic acids. These aramids have inherent viscosities of 0.43-0.84 dl/g and were obtained in quantitative yield. 相似文献
7.
A. S. Jadhav N. N. Maldar B. M. Shinde S. P. Vernekar 《Journal of polymer science. Part A, Polymer chemistry》1991,29(2):147-153
New polymides and copolyamides containing silicon and sulfone ether linkages, soluble in common aprotic solvents and having inherent viscosities of 0.3–0.6 dL/g have been synthesized by solution condensation of bis-(4-chlorocarbonyl phenyl) dimethylsilance (DMSC) and/or bis-(4-chlorocarbonyl phenyl) diphenylsilance (DPSC) with 4,4′-[sulfonylbis-(4,1-phenylenoxy)] bisbenzenamine, 3,3′-[sulfonylbis (4,1-phenyleneoxy)] bisbenzenamine, and bis (4-aminophenyl) ether. These polymers were characterized by infrared spectra, solution viscosity, thermooxidative degradation, differential scanning calorimetry, and x-ray diffraction. These polymers show good thermal stability. 相似文献
8.
Yasufumi Watanabe Yuji Shibasaki Shinji Ando Mitsuru Ueda 《Journal of polymer science. Part A, Polymer chemistry》2004,42(1):144-150
We prepared new semiaromatic polyimides from alicyclic dianhydrides and aromatic diamines containing adamantyl and biadamantyl units. Polycondensations were performed in 1‐methyl‐2‐pyrrolidinone at room temperature for 7 h and then 80 °C for 23 h, giving poly(amic acid)s with inherent viscosities up to 0.58 dL/g. Poly(amic acid)s were converted to corresponding poly(imide)s by thermal treatment. Poly(imide)s showed relatively high thermal stability (5% weight loss around 450 °C) and low dielectric constants (2.69–2.79). © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 144–150, 2004 相似文献
9.
Russian Chemical Bulletin - Polyamides based on the 5-hydroxymethylfurfural derivative (2,5-furandicarboxylic acid dichloroanhydride) and diamines of both aromatic and aliphatic series were... 相似文献
10.
Synthesis and characterization of novel polyimides derived from pyridine-bridged aromatic dianhydride and various diamines 总被引:2,自引:0,他引:2
A new kind of pyridine-bridged aromatic dianhydride monomer, 4-phenyl-2,6-bis[4-(3,4-dicarboxyphenoxy)phenyl]-pyridine dianhydride (PPDA), was successfully synthesized by modified Chichibabin reaction of benzaldehyde and substituted acetophenone, 4-(3,4-dicyanophenoxy)-acetophenone (DCAP), followed by acidic hydrolysis of the intermediate tetranitrile and cyclodehydration of the resulting tetraacid. The pyridine-bridged aromatic dianhydride was employed to synthesized a series of new pyridine-containing polyimides by polycondensation with various aromatic diamines in N-methyl-2-pyrrolidone (NMP) via the conventional two-step method, i.e. ring-opening polycondensation forming the poly(amic acid)s and further thermal or chemical imidization forming polyimides. The inherent viscosities of the resulting polyimides were in the range of 0.49-0.63 dL/g, and most of them were soluble in aprotic amide solvents and cresols, such as N,N-dimethylacetamide (DMAc), NMP, and m-cresol, etc. Meanwhile, strong and flexible polyimide films were obtained, which have good thermal stability with the glass transition temperatures (Tg) of 223-256 °C, the temperature at 5% weight loss of 523-569 °C, and the residue at 700 °C of 52.1-62.7% in nitrogen, as well as have outstanding mechanical properties with the tensile strengths of 70.7-97.6 MPa and elongations at breakage of 7.9-9.7%. Wide-angle X-ray diffraction measurements revealed that these polyimides were predominantly amorphous. 相似文献
11.
M. S. Sinsky R. G. Bass J. W. Connell P. M. Hergenrother 《Journal of polymer science. Part A, Polymer chemistry》1986,24(9):2279-2295
Novel poly(enamine-ketones) were prepared with inherent viscosities as high as 1.99 dL/g using the Michael-type addition of various diamines to 1,1′-(1,3 or 1,4-phenylene)bis(3-phenyl-2-propyn-1-one) in m-cresol at 60–130°C. Tough, clear, amber films with tensile strengths of 12, 400 psi and tensile moduli of 397, 000 psi were cast from solutions of the polymers in chloroform. The polymers exhibited Tgs as high as 235°C and weight losses of 14% after aging at 232°C in circulating air for 60 h. The synthesis and characterization of several poly(enamine-ketones) are discussed. 相似文献
12.
Mitsuru Ueda Akira Sato Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1979,17(3):783-787
Catalytic actions of various additives were studied in the polycondensation of di(4-nitrophenyl) isophthalate with bis(4-aminophenyl) ether in N-methyl-2-pyrrolidone, and 1-hydroxybenzotriazole (HOBt) was found to be a highly effective catalyst that yielded high-molecular-weight polyamide. In addition to the polycondensation of the 4-nitrophenyl ester, the polymerization of negatively substituted phenyl esters like di(2,4,5-trichlorophenyl) isophthalate was also accelerated by HOBt. For the HOBt-catalyzed aminolysis of esters a bifunctional concerted mechanism that involves an eight-membered transition state was proposed. 相似文献
13.
R. G. Bass M. S. Sinsky J. W. Connell R. O. Waldbauer P. M. Hergenrother 《Journal of polymer science. Part A, Polymer chemistry》1989,27(1):171-183
Poly(enamine-ketones) were prepared by the nucleophilic (Michael-type) addition of various aromatic diamines to 1,1′-(1,3- or 1,4-phenylene)bis(2-propyn-1-one)(1,3 or 1,4-PPO) in m-cresol at 5–23°C. The low molecular weight polymers (inherent viscosity of 0.25 dL/g) exhibited limited solubility in organic solvents. Glass transition temperatures were generally undetectable by differential scanning calorimetry while polymer decomposition temperatures (10% weight loss), as measured by thermogravimetric analysis, were observed from 355 to 419°C. Polymers prepared from 1,4-PPO were semi-crystalline as shown by wide-angle X-ray diffraction. The poly(enamine-ketone) structure was confirmed by matching infrared spectral characteristics of the polymers with those of well-characterized model enamine ketones. 相似文献
14.
Yoshiyuki Oishi Munirathina Padmanaban Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1992,30(7):1363-1368
Silylated aromatic polyureas were synthesized by the polyaddition of N,N′-bis(trimethylsilyl)-substituted aromatic diamines to aromatic diisocyanates in various organic solvents at a temperature ranging from 30 to 100°C. Colorless and transparent films of the silylated polyureas were obtained by casting directly from these solutions in a dry nitrogen atmosphere. The silylated polyureas thermally decomposed at around 200°C and were easily desilylated with alcohol to convert to almost amorphous aromatic polyureas having inherent viscosities of 0.4–1.0 dL/g. The polyureas exhibited better solubility in organic solvents such as N,N-dimethylacetamide, N-methyl-2-pyrrolidone, and dimethyl sulfoxide and had somewhat lower thermal decomposition temperatures (around 300°C) than the polyureas prepared by a conventional method from the parent aromatic diamines and diisocyanates. 相似文献
15.
Yoshio Imai Katsunori Kojima 《Journal of polymer science. Part A, Polymer chemistry》1972,10(7):2091-2096
The reaction of phthalic thioanhydride and aniline yielded N-phenylphthalimide quite readily. The reaction was strongly dependent on solvent and temperature. Various additives tried as a reaction promoter were almost ineffective. By the extension of the model reaction, polyimides were prepared in a simple one-step synthesis from pyromellitic dithioanhydride and aromatic diamines in dimethylacetamide or other solvents. Polymers with inherent viscosity up to 0.3 in concentrated sulfuric acid were obtained in approximately quantitative yield. 相似文献
16.
Yoshiyuki Oishi Shigeyuki Harada Masa-Aki Kamimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1989,27(10):3393-3403
New fluorine-containing aromatic polyamides with inherent viscosities of 0.4–1.8 dL/g were prepared by the low temperature solution polycondensation of tetrafluoroisophthaloyl and tetrafluoroterephthaloyl chlorides with N,N′-bis(trimethylsilyl)-substituted aromatic diamines. The aromatic polyperfluoroisophthalamides were amorphous polymers with glass transition temperatures around 280°C, whereas the polyperfluoroterephthalamides were crystalline. Most of these aromatic polyamides were soluble in organic solvents, and began to decompose around 330°C in air or nitrogen atmosphere. 相似文献
17.
Masaru Yoneyama K. D. Athula Kuruppu Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1988,26(11):2917-2922
Aromatic polyamides (aramids) having inherent viscosities of 0.5–1.10 dL/g were prepared by the direct polycondensation of 1,1,3-trimethyl-3-(4-carboxyphenyl)indane-5-carboxylic acid with various aromatic diamines using triphenyl phosphite and pyridine as the condensing agents. Copolyamides were also prepared by a similar procedure from a mixture of the phenylindane diacid, terephthalic acid, and p-phenylenediamine. Almost all of the aramids were soluble in a variety of solvents such as N-methyl-2-pyrrolidone, pyridine, and m-cresol, and afforded transparent and tough films by the solution casting. These aramids and copolyamides had glass transition temperatures in the range of 290–355°C, and started to lose weight at 340°C in air. 相似文献
18.
Chin-Ping Yang Yoshiyuki Oishi Masa-Aki Kakimoto Yoshio Imai 《Journal of polymer science. Part A, Polymer chemistry》1989,27(12):3895-3901
Aromatic polyamides (aramids) having pendant t-butyl group were synthesized by the direct polycondensation of 5-t-butylisophthalic acid with various aromatic diamines in N-methyl-2-pyrrolidone (NMP) using triphenyl phosphite and pyridine as condensing agents. The aramids having inherent viscosities of 0.6–2.4 dL/g were obtained in quantitative yields. These polymers were readily soluble in various solvents such as NMP,N,N-dimethylacetamide, dimethyl sulfoxide, and pyridine, and gave transparent, tough and flexible films by casting from the NMP solutions. The aramids had glass transition temperatures between 250 and 330°C, and started to lose weight around 350°C, with 10% weight loss being recorded at about 450°C in air. 相似文献
19.
Rakhimova E. B. Ozden I. V. Meshcheryakova E. S. Khalilov L. M. Ibragimov A. G. 《Russian Journal of Organic Chemistry》2015,51(12):1788-1792
Russian Journal of Organic Chemistry - A procedure has been developed for the synthesis of N,N′-disubstituted bis-1,5,3-dithiazepanes by samarium-catalyzed recyclization of... 相似文献
20.
Yoshio Imai Mitsuru Ueda Motokazu Ishimori 《Journal of polymer science. Part A, Polymer chemistry》1976,14(2):299-306
A series of polypropionamide-ureas was synthesized by the polymerization of N-mesyloxysuccinimide with diamines in polar aprotic solvents in the presence of acid acceptors. The polymerization proceeded through the formation of ring-opened adducts, followed by elimination and rearrangement yielding β-isocyanatopropionamide derivatives, which in turn were polymerized to afford polypropionamide-ureas. These polymers had inherent viscosities in the range of 0.1–0.2. Polymers having aliphatic chains which were fusible below 240°C were soluble in acidic solvents, whereas those with aromatic residues dissolved in polar aprotic solvents. Marked decomposition of the polyamide-ureas under thermogravimetric analysis generally occurred at around 320°C under nitrogen. 相似文献