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烷氧基邻苯二腈是酞菁合成的重要中间体,但高歧化度烷氧基邻苯二腈的合成由于副产物多,产率低下而成为此类酞菁应用的"瓶颈".文中对反应副产物进行了分离纯化,并利用红外、气质联用、1HMR和元素分析等测试手段对其进行了表征.且根据测试数据推导出了副产物结构式为1,2,1'2' 四腈基 3,3' 二苯基醚.这一副反应机制的阐明,对于寻求对主反应有利的条件,具有重要的意义. 相似文献
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New 3,3‐diphenylpropoxyphthalonitrile (5) was obtained from 3,3‐diphenylpropanol (3) and 4‐nitrophthalonitrile (4) with K2CO3 in DMF at 50 °C. The novel cobalt(II) phthalocyanine complexes, tetrakis‐[2‐(1,4‐dioxa‐8‐azaspiro[4.5]dec‐8‐yl)ethoxy] phthalocyaninato cobalt(II) (2) and tetrakis‐(3,3‐diphenylpropoxy)phthalocyaninato cobalt(II) (6) were prepared by the reaction of the phthalonitrile derivatives 1 and 5 with CoCl2 by microwave irradiation in 2‐(dimethylamino)ethanol for at 175 °C, 350 W for 7 and 10 min, respectively. These new cobalt(II)phthalocyanine complexes were characterized by spectroscopic methods (IR, UV–visible and mass spectroscopy) as well as elemental analysis. Complexes 2 and 6 are employed as catalyst for the oxidation of cyclohexene using tert‐butyl hydroperoxide (TBHP), m‐chloroperoxybenzoic acid (m‐CPBA), aerobic oxygen and hydrogen peroxide (H2O2) as oxidant. It is observed that both complexes can selectively oxidize cyclohexene to give 2‐cyclohexene‐1‐ol as major product, and 2‐cyclohexen‐1‐one and cyclohexene oxide as minor products. TBHP was found to be the best oxidant since minimal destruction of the catalyst, higher selectivity and conversion were observed in the products. Copyright © 2012 John Wiley & Sons, Ltd. 相似文献
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《Mendeleev Communications》2022,32(3):327-330
Carbon–carbon composites (C/C) were produced from carbon fiber reinforced phthalonitrile (CFRP) matrix composites in a two-step impregnation–carbonization procedure. After graphitization at 1800 °C, the obtained C/C composites demonstrated highly crystalline structure and properties characteristic of composites derived from phenolic matrix CFRP by the industrial procedure: d = 1.73 g cm?3, interlaminar shear strength was 14.1 MPa, compression strength was 139.8 MPa, and coefficient of friction was in the range 0.32–0.34. 相似文献
4.
Satya B. Sastri Teddy M. Keller 《Journal of polymer science. Part A, Polymer chemistry》1999,37(13):2105-2111
This article compares the cure behavior and properties of phthalonitrile polymers derived from three different monomers, namely, 4,4′-bis(3,4-dicyanophenoxy)biphenyl, 2,2-bis[4-(3,4-dicyanophenoxy)phenyl]hexafluoropropane and 2,2-bis[4-(3,4-dicyanophenoxy)phenyl]propane. Rheometric measurements with monomer melt in the presence of an aromatic diamine curing agent reveal that the rate of the cure reaction differs for the three monomers. The rate is dependent on the concentration of the curing agent. The glass transition temperature advances with increasing extent of cure and disappears upon postcure at temperatures in excess of 350°C. Based on thermogravimetric analysis, the thermal stability of all three polymers are comparable, whereas the fluorine-containing resin shows the best oxidative stability at elevated temperatures. Microscale calorimetric studies on all three polymers reveal that the char yields are high and the total heat release upon exposure to 50 kW/m2 flux for each polymer is low, compared to other thermosets. Flexural strength ranges between 80–120 MPa. The water uptake under ambient conditions is less than 3% by weight after submersion in water for seven months. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 2105–2111, 1999 相似文献
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Enhanced properties of phthalonitrile resins under lower curing temperature via complex curing agent
Zhihuan Weng Yue Hu Yu Qi Shouhai Zhang Cheng Liu Jinyan Wang Xigao Jian 《先进技术聚合物》2020,31(2):233-239
High curing temperature has been restricting the application and development of phthalonitrile resin. A complex curing agent containing melamine (ME) and ZnCl2 was developed to promote the curing reaction of resorcinol‐based phthalonitrile resin (DPPH). The thermal stability of ME can be significantly enhanced via adding ZnCl2, which was due to the interaction between ZnCl2 and amino group in ME. Moreover, the activities of pristine ZnCl2 and ME were improved via mixing, especially, the curing temperature for DPPH can be effectively reduced. Even at a curing temperature of 300°C, the 5% weight loss temperature of the resulting resin cured with complex curing agent still exceeded 500°C, which was much higher than those with pristine curing agents. In addition, the good long‐term oxidation stability and relatively low water absorption can also be obtained in the resins cured with novel curing agent. This work affords a facile route for designing high‐performance curing agent to improve the curing process of phthalonitrile resin. 相似文献
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对新型取代基酞菁和酞菁晶体合成和性质进行了研究。因为酞菁在信息、医疗、化工等众多领域有很广泛的应用,所以近百年来一直是科学家研究的热点课题。酞菁经过近百年的研究,科学家已经合成了上万种酞菁衍生物,但是,随着科技的不断进步,人类社会不断发展的需求,具有新特性的新型酞菁的获得仍是相关科技工作者孜孜以求的目标。为此,在本论文中,我们改进了合成方法,合成了新型的桥联酞菁材料:1,11,15,25-四羟基-4,8,18,22-二(桥联二丙羧基)酞菁铜,表征其结构。并研究电化学性质。首先以丙二酸和3,6-二羟基邻苯二腈为起始原料,以水为溶剂,加入浓硫酸作为催化剂,先合成前体,即丙二酸3,3′-二(6–羟基邻苯二腈)脂。然后再用丙二酸 3,3′-二(6-羟基邻苯二腈)脂与一水合乙酸铜,以正戊醇为溶剂,以DBU为催化剂,合成了1,11,15,25-四羟基-4,8,18,22-二(桥联二丙羧基)酞菁铜,其分子式是C38H16N8O12Cu。对1,11,15,25-四羟基-4,8,18,22–二(桥联二丙羧基)酞菁铜进行紫外吸收及荧光光谱测定,证明合成产物是目标产物,并研究了1,11,15,25-四羟基-4,8,18,22-二(桥联二丙羧基)酞菁铜的电化学性质。 相似文献
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Devendra Kumar Uday Razdan Alka D. Gupta 《Journal of polymer science. Part A, Polymer chemistry》1993,31(9):2319-2331
A proton-NMR study of the condensation reaction (step 1) of 4-(3′-aminophenoxy)phthalonitrile (4-3′APPN) ( I ) in an aprotic solvent with various aromatic dianhydrides demonstrated the formation of the corresponding bisamic acid within 5–10 min. There was no effect of the electron affinity of the used aromatic dianhydrides on the time of the condensation reaction and also no charge-transfer complex formation was indicated. Proton-NMR study of the synthesized bisaryloxy-bisimido-bisphthalonitriles at 250.1 MHz has revealed general findings for their NMR characterization. The coupling constant (J) value for the ortho-coupled protons of the phthalonitrile ring of the 4–3′-APPN portion is 8.8 ± 0.05 Hz and that for the ortho-coupled protons of the aminophenoxy ring of 4–3′-APPN is 8.1 ± 0.05 Hz. The coupling constant (J) values for ortho-coupled protons of the dianhydride portion range from 8.1 to 7.5 Hz. Various thermally polymerizable bisaryloxybisimido-bisphthalonitriles (BBBP) ( X, XI, XII , and XIII ) containing dimethylsilane, hexafluoroisopropylidene, ether, and keto groups, suitable for the development of thermooxidative stable, void-free composites, were synthesized by two methods. In method 1,4–3′-APPN ( I ) in N,N-dimethylacetamide (DMAC) was condensed (step 1) with bis(3,4-dicarboxyphenyl)dimethylsilane dianhydride (SIDA) ( II ), 4, 4′-hexafluoroisopropylidenediphthalic anhydride (6FDA) ( III ), bis(3,4-dicarboxyphenyl)ether dianhydride (ODPA) ( IV ), and 3,4,3′,4′-benzophenonetetracarboxylic dianhydride (BTDA) ( V ), respectively, to give the corresponding bisamic acids. Thermal cyclodehydration of the intermediate bisamic acid at 160°C gave the bisphthalonitriles. In method 2, the second step of thermal cyclodehydration was performed in situ in refluxing toluene. The characterization of the synthesized bisaryloxy-bisimido-bisphthalonitriles (BBBP) was performed using FT-IR, 1H-NMR, 13C-NMR, mass spectroscopy, and elemental analysis. A preliminary study indicated that thermal-polymerization of these bisphthalonitriles (BBBP) gave tough, thermosetting polymers, useful for high-temperature applications. © 1993 John Wiley & Sons, Inc. 相似文献
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《先进技术聚合物》2018,29(7):1922-1929
The effects of inorganic particles such as Al2O3 and B4C on the solidification kinetics and heat resistance of phthalonitrile resin were investigated. The properties of the blends and the cured products were tested by rheometer, differential scanning calorimetry, Fourier transform infrared spectroscopy, and thermogravimetric analysis. The results revealed that B4C and Al2O3 inorganic particles could prolong the gel time of phthalonitrile resin and broaden the processing window. The curing kinetic analysis showed that the presence of the particles could significantly reduce the curing activation energy of phthalonitrile resins by 72.38 kJ/mol down to 43.03 kJ/mol. Meanwhile, the heat resistance of the phthalonitrile resin was improved. Among them, the blend system combined with 30% B4C showed prominent thermoresistance. And while the Td5% weight loss temperature was 600°C, char yield at 1000°C was higher than 86% under nitrogen atmosphere; while the Td5% weight loss temperature was 581°C, char yield at 1000°C was higher than 80% under air atmosphere. Hence, the resulting resins were good candidate matrix of high‐temperature structural composites. 相似文献