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1.
The known polymerization of 4,4′-difluorobenzophenone (DFB) with the dianion of hydroquinone to poly(phenylene ether ether ketone) (PEEK) and polymerization of either DFB with the dianion of 4,4′-dihydroxybenzophenone or self polycondensation of the anion of 4-hydroxy-4′-fluoro-benzophenone to poly(phenylene ether ketone) (PEK) were studied in N-cyclohexyl-2-pyrrolidone (CHP), which is a high-boiling aprotic polar solvent. The formation of high-molecular weight PEEK and PEK in this solvent was very efficient. The reactivity in CHP can be ascribed to effective solvation of metal ions rendering the anion very reactive toward nucleophilic substitution. The polymerization was extended to 4,4′-bis(4-fluorobenzoyl)diphenyl ether and 1,4-bis[4-(4-fluorobenzoyl)phenoxy]benzene to give a high molecular weight polymer with PEK and PEEK repeating units and PEEK respectively. The polymerization of DFB with purified anhydrous sodium sulfide in CHP gave rapidly a high molecular weight poly(phenylene ketone sulfide) (PKS). In contrast, diphenyl sulfone (DPS) was not very effective in obtaining such a high molecular weight PKS even with prolonged heating, which suggests the uniqueness of CHP in promoting a high degree of polymerization.  相似文献   

2.
Gas-phase reactions of brominated diphenyl ethers with OH radicals   总被引:1,自引:0,他引:1  
A small volume reaction chamber coupled to a mass spectrometer was used to study the gas-phase kinetics and mechanism of the reaction of OH radicals with diphenyl ether and seven polybrominated diphenyl ethers (PBDEs) with 1-2 bromines. Relative rate constants for these reactions were determined using isopropyl nitrite photolysis in He-air mixtures at approximately 740 Torr between the temperatures of 326-388 K. The Arrhenius expression for each compound was used to extrapolate the following OH rate constants at 298 K (in units of 10(-12) cm3 molecule(-1) s(-1), with 95% confidence intervals): diphenyl ether, 7.45 +/- 0.13; 2-bromodiphenyl ether, 4.7; 3-bromodiphenyl ether, 4.6; 4-bromodiphenyl ether, 5.7; 2,2'-dibromodiphenyl ether, 1.3; 2,4-dibromodiphenyl ether, 3.8; 3,3-dibromodiphenyl ether, 3.2; and 4,4'-bromodiphenyl ether, 5.1. The measured OH rate constants are in reasonable agreement with those predicted by structure activity relationships. Positive temperature dependences of these OH rate constants are observed for all compounds measured except for diphenyl ether and 4,4'-dibromodiphenyl ether. Bromophenols (in yields up to 20% relative to the amount of PBDE consumed) and Br2 were characterized as products of these reactions, suggesting that OH addition to ipso positions of these brominated aryls may be an important reaction pathway.  相似文献   

3.
A new monomer, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP), was prepared by Friedel–Crafts reaction of 4‐bromobenzoyl chloride and diphenyl, followed by condensation with potassium phenoxide. Novel poly(ether ketone ketone) (PEKK)/poly(ether ketone diphenyl ketone ether ketone ketone) (PEKDKEKK) copolymers were synthesized by electrophilic Friedel–Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of diphenyl ether (DPE) and BPOBDP, in the presence of anhydrous aluminum chloride and N‐methyl‐pyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers obtained were characterized by various analytical techniques such as FT‐IR, DSC, TGA, and wide‐angle X‐ray diffraction (WAXD). The results showed that the resulting copolymers exhibited excellent thermal stability due to the existence of diphenyl moieties in the main chain. The glass transition temperatures are above 152°C, the melting temperatures are above 276°C, and the temperatures at a 5% weight loss are above 548°C in nitrogen. The copolymers with 50–70 mol% BPOBDP had tensile strengths of 101.5–102.7 MPa, Young's moduli of 3.23–3.41 GPa, and elongations at break of 12–17%. All these copolymers were semicrystalline and insoluble in organic solvents. Copyright © 2008 John Wiley & Sons, Ltd.  相似文献   

4.
Poly(arylene ether sulfone) copolymers derived from 9,9-bis(4-hydroxyphenyl)fluorene, bisphenol S and 4,4′-difluorodiphenylsulfone and poly(arylene ether ketone) copolymers derived from 4-phenoxybiphenyl, diphenyl ether and isophthaloyl chloride were prepared as precursor polymers for sulfonation reaction in which sulfonic groups are introduced quantitatively into specified positions. Sulfonation reaction for these two series of copolymers by concentrated sulfuric acid was successfully carried out to give sulfonated polymers with controlled positions and degree of sulfonation. Thermal stability, moisture absorption and proton conductivity for these two series of copolymers were measured and the results were compared to those of perfluorosulfonic acid polymers.  相似文献   

5.
气液色谱有限浓度法研究醇类在芳烃溶剂中的自缔合及交叉缔合王毅琳,周效贤,李松林,郑国康(兰州大学化学系,兰州,730000)关键词醇,自缔合,交叉缔合前文[1]用气液色谱有限浓度法研究了C4各正构醇在角鲨烷中的活度系数.本文报道在313.15K下对C...  相似文献   

6.
Methyl 3-(N-arylamino)-2-cyano-3-methylthioacrylates 3a-h , which are readily prepared by the reaction of the ketene dithioacetal, methyl 2-cyano-3,3-bis(methylthio)acrylate ( 1 ) with arylamines, was heated at reflux in diphenyl ether to give the corresponding 2-methylthio-4-hydroxyquinoline-3-carbonitriles 4a-h in 14–77% yields. The reaction of 1 with excess aryl amines in diphenyl ether at reflux gave also the corresponding 2-arylamino-4-hydroxyquinoline-3-carbonitriles 6a-d . The 2-methylthioquinoline-3-carbonitriles 4a-h , thus obtained, are useful intermediates for the synthesis of various quinoline derivatives.  相似文献   

7.
A new monomer, 4,4′‐bis(4‐phenoxybenzoyl)diphenyl(BPOBDP), was synthesized via a two‐step synthetic procedure. A series of novel poly(ether sulfone ether ketone ketone)/poly(ether ketone diphenyl ketone ether ketone ketone) copolymers were prepared by electrophilic Friedel–Crafts solution copolycondensation of isophthaloyl chloride (IPC) with a mixture of 4,4′‐diphenoxydiphenylsulfone (DPODPS) and 4,4′‐bis(4‐phenoxybenzoyl)diphenyl (BPOBDP), in the presence of anhydrous aluminum chloride and N‐methylpyrrolidone (NMP) in 1,2‐dichloroethane (DCE). The copolymers with 10–50 mol% DPODPS are semicrystalline and have remarkably increased Tgs over commercially available PEEK and PEKK. The copolymers with 40–50 mol% DPODPS had not only high Tgs of 170–172°C, but also moderate Tms of 326–333°C, which are extremely suitable for melt processing. These copolymers have tensile strengths of 96.5–108.1 MPa, Young's moduli of 1.98–3.05 GPa, and elongations at break of 13–26% and exhibit excellent thermal stability and good resistance to acidity, alkali, and common organic solvents. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

8.
A series of macrocyclic(thio arylene) oligomers were synthesized under high dilution conditions by reacting diphenyl ether, diphenyl, diphenyl disulfide or diphenyl methane with dichloro disulfide in the presence of trace amount of iron powder by a one-step method. The composition of these macrocyclic oligomers was analyzed by MALDI-TOF technology, and the experimental results showed that the cyclics were a mixture with repeating units separated by one to seven sulfur atoms. These macrocyclics can undergo ring-opening polymerization to form linear polymers under mild conditions. The glass transition temperatures of produced polymers varied with the sulfur content.  相似文献   

9.
合成了一种聚芳醚酮齐聚物 4 ,4′-双 (对氟苯甲酰基 )二苯醚 ,并以IR ,DSC ,13CNMR等技术对其进行了表征。运用多晶粉末X射线衍射方法 ,对其晶体结构进行了确定 ,其晶体结构为首次报道。  相似文献   

10.
Polyaromatic ether-ketones possessing high thermal stabilities were prepared by Friedel—Crafts polymerizations from 4-phenoxybenzoyl chloride and from 4,4′-dichloroformyldiphenyl ether and diphenyl ether. Sulfonation and subsequent sulfamidation of these polymers afforded polyaromatic ether-ketone sulfonamides with different degrees of substitution depending on the reaction conditions. Sulfonation reactions with chlorosulfonic acid did not cause much degradation on the polymers. The polysulfonamides were soluble in various organic solvents such as N,N-dimethylformamide, dimethylsulfoxide, or chloroform, and could be cast into transparent films. These polymers may be used as desalination membranes.  相似文献   

11.
用荧光素作荧光探针 ,研究了可聚合凝胶因子 4,4′ 二 (α 甲基丙烯酰氧基 1 ,3 亚乙氧基羰基丙酰氨基 )二苯甲烷 (BMDM)在二苯醚的凝胶化过程中的聚集状态 .研究结果发现 ,与荧光素在二苯醚溶液中的荧光光谱相比 ,在凝胶中出现了 1 0~2 5nm的红移 ;而且发现分子凝胶的凝胶化时间随着BMDM浓度的增加而减小 .偏振荧光法研究分子凝胶的取向发现 ,该分子凝胶的形成过程是从各向同性的溶液(P0 =0 )向各向异性的溶胶 (P>0 )转变 ,再向各向同性的凝胶 (Pgel≈ 0 )转变的过程  相似文献   

12.
The syntheses of four new monomers and two new polyaromatic pyrazines are described. The monomers; bis-p,p′-(octanoyl)diphenyl ether (Ia), bis-p,p′-(hexadecanoyl)diphenyl ether (Ib), bis-p,p′-(α-bromooctanoyl)diphenyl ether (IIa), and bis-p,p′-(α-bromohexadecanoyl)diphenyl ether (IIb), were produced by Friedel-Crafts acylation of diphenyl ether with the corresponding acyl chloride and subsequent α-bromination. Prepolymers were synthesized by the condensation of (IIa) and (IIb) with ammonia in N,N-dimethylformamide (DMF), and polymers were prepared by subsequent melt condensation of the prepolymer to produce poly[2,5-(oxydiphenylene)-3,6-(dihexyl)pyrazine] (IIIa), and poly[2,5-(oxydiphenylene)-3,6-(ditetradecyl)pyrazine] (IIIb). Polymer IIIa was thermally (stable at >400°C while polymer IIIb was a tacky substance). The inherent viscosity of IIIa produced by 12 hr of melt condensation was 0.30 dl/g in formic acid. Additional heating in excess of 24 hr gave a slightly soluble polymer. The inherent viscosity of IIIb produced by 40 hr of melt condensation was 0.37 dl/g in formic acid.  相似文献   

13.
《Thermochimica Acta》1987,109(2):317-329
Heat capacities of some amines (aniline, N-methyl aniline, meta-phenylene diamine, diamino diphenyl methane, diamino diphenyl sulfone and diamino diphenyl oxide) and two epoxy resins (phenyl glycidyl ether and diglycidyl ether of bisphenol A) have been determined in the solid and liquid states versus temperature. The heat capacity increments related to the functional groups have been evaluated compared to references like benzene, aniline and phenyl glycidyl ether.  相似文献   

14.
新醚酮聚酰亚胺   总被引:3,自引:0,他引:3  
二苯醚分别与对位和间位 硝基苯甲酰氯以及间苯二甲酰氯反应合成了五种醚酮双硝基化合物,经还原生成五种相应的二胺,其中,4,4′ 双(3 氨基苯甲酰基)二苯醚(BADPE)分别与均四苯甲酸二酐(PMDA)、3,3′,4,4′ 二苯甲酮四甲酸二酐(BTDA)和4,4′ 氧化二邻苯二甲酸二酐(ODPA)聚合亚胺化后可生成橙色透明薄膜,其韧性好,拉伸强度高,耐溶剂,并有一定的耐强碱性.它们的Tg分别为2735、239和224℃,它们的高温氧化稳定性均很好,它与BTDA聚合而成的聚酰胺酸对铝/铝及铜/铜等金属都有极好的胶粘性,亚胺化后胶接强度极高.  相似文献   

15.
Conclusions On bromination of diphenyl ether the first bromine atom enters into the hydrocarbon ring, and the second bromine atom enters into the ethereal ring. The same principle was found for the chloromethylation of diphenyl ether.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 1, pp. 142–144, January, 1969.  相似文献   

16.
A new alizarin based azacrown ether N-(alizarin-4-methylene)-4-azadibenzo-18-crown-6 (AMADCE) was synthesized, for the transportation of fluoride ions, by reacting 4-aza dibenzo 18-crown-6 with alizarin in the presence of formaldehyde. The compound forms a stable purple-red coloured complex with Zr(IV) in 0.5-1.0 M hydrochloric acid and gets quantitatively extracted into diphenyl ether. This diphenyl ether extract of the Zr(IV) complex instantaneously transfers fluoride ions from the aqueous phase, which was utilised for the sensitive determination and transportation of fluoride ions through the liquid membrane. The conditions like concentration of membrane phase, acidity of the source phase and the receiving phase, and the transportation time were optimized. The continuous transportation of fluoride ions was achieved by adding receptor ions like La3+ and Ca2+ in the receiving phase. The rate constant K and t1/2 for the transportation were determined. The studies were extended for the removal of fluoride ions through the liquid membrane from the ground water samples and industrial effluent.  相似文献   

17.
选取不同分子量的聚乙烯/二苯醚作为聚合物稀释剂体系,通过浊点及结晶温度绘制了体系的热力学相图;并在不同淬冷温度下,通过热致相分离法制备了聚乙烯微孔滤膜。讨论了聚合物分子量及淬冷温度对成膜孔结构的影响。结果表明:聚合物的分子量不仅影响微孔滤膜断面的孔径,还影响其形态和结构。  相似文献   

18.
The first total synthesis of cytotoxic diphenyl ether‐type diarylheptanoids, galeon and pterocarine, was described in which the Ullmann reaction was employed at the final step for the diaryl ether formation of key intermediate, 1‐(3‐bromo‐4‐benzyloxyphenyl)‐7‐(4‐hydroxy‐3‐methoxyphenyl)heptan‐3‐one, assembled by a series of cross‐aldol condensation from 3‐methoxy‐4‐benzyloxybenzaldehyde.  相似文献   

19.
A series of diphenyl ether derivatives were developed and showed promising potency for inhibiting InhA, an essential enoyl acyl carrier protein reductase involved in mycolic acid biosynthesis, leading to the lysis of Mycobacterium tuberculosis. To understand the structural basis of diphenyl ether derivatives for designing more potent inhibitors, molecular dynamics (MD) simulations were performed. Based on the obtained results, the dynamic behaviour in terms of flexibility, binding free energy, binding energy decomposition, conformation, and the inhibitor–enzyme interaction of diphenyl ether inhibitors were elucidated. Phe149, Tyr158, Met161, Met199, Val203 and NAD+ are the key residues for binding of diphenyl ether inhibitors in the InhA binding pocket. Our results could provide the structural concept to design new diphenyl ether inhibitors with better enzyme inhibitory activity against M. tuberculosis InhA. The present work facilitates the design of new and potentially more effective anti-tuberculosis agents.  相似文献   

20.
Silicon-containing divinyl ether monomers were synthesized by the addition reaction of glycidyl vinyl ether ( 1 ) with various silyl dichlorides using tetra-n-butylammonium bromide (TBAB) as a catalyst. The reaction of 1 with diphenyl dichlorosilane gave bis-[1-(chloromethyl)-2-(vinyloxy)-ethyl]diphenyl silane ( 3a ) in 89% yield. Polycondensations of 3a with terephthalic acid were also carried out using 1,8-Diazabicyclo[5.4.0]-7-undecene (DBU) to afford silicon-containing polyfunctional vinyl ether oligomers ( 5 ). A multifunctional Si-monomer with both vinyl ether and methacrylate groups ( 7 ) was prepared by the reaction of 3a with potassium methacrylate using TBAB as a phase transfer catalyst. Photoinitiated cationic polymerizations of these vinyl ether compounds proceeded rapidly using the sulfonium salt, bis-[4-(diphenyl-sulfonio)phenyl]sulfide-bis-hexafluorophoshate (DPSP), as the cationic photoinitiator in neat mixtures upon UV irradiation. Multifunctional monomer 7 with both vinyl ether and methacrylate groups showed “hybrid curing properties” using both DPSP and the radical photoinitiator, 2,4,6-trimethylbenzoyl diphenylphoshine oxide (TPO). © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35: 3217–3225, 1997  相似文献   

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