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1.
通过傅克酰基化反应合成4,4'-二(4-氟苯甲酰基)二苯醚、4,4'-二(五氟苯甲酰基)二苯醚、4,4'-二(4-氟苯甲酰基)二苯硫醚以及4,4'-二(五氟苯甲酰基)二苯醚4种长链双卤单体,并进一步制备了含二氮杂萘酮聚芳醚酮聚合物.通过多氟取代双卤单体在含二氮杂萘酮聚芳醚酮聚合物主链中引入氟原子.多氟取代双卤单体具有多...  相似文献   

2.
tert-Butyl substituted poly (aryl ether ketone)s with relatively high molecular weights were prepared by the Ni-catalyzed polymerization of tert-butyl substituted aromatic dichlorides containing ether ketone unit. These polymers were amorphous and soluble in common organic solvents, such as THF, dichloromethane, and chloroform. De-tert-butylation of the polymer by the treatment of trifluoromethanesulfonic acid in the presence of toluene proceeded smoothly and produced crystalline poly (aryl ether ketone). © 1994 John Wiley & Sons, Inc.  相似文献   

3.
A series of novel poly(thioether ether ketone imide)s (PTEKIs) bearing the thioether and ketone groups with high molecular weights (Mw: 87,800–150,100 g/mol) were synthesized by aromatic nucleophilic substitution reaction. The polymers were characterized by Fourier transform infrared spectra (FT‐IR), 1H NMR, GPC, and elemental analysis. The composition of the copolymers varied systematically in order to study its relation with polymer properties. Increase in the content of 3‐substituted phthalimide moiety in the polymer backbone improves the solubility in tested solvents, and increases the glass transition temperature (Tg), whereas copolymers with high content of 3‐substituted phthalimide demonstrated to be inferior thermal stability. The PTEKI films also exhibited good optical transparency, including the cutoff wavelengths lower than 400 nm and transmittances higher than 77% at 450 nm. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

4.
This study reports a method to prepare fully aromatic poly(ether ketone) thermosets. The cyclization of 2′,5′‐dimethoxy[1,1′‐biphenyl]‐2,5‐diol and a difluoro monomer was carried out under pseudo high dilution condition. Two types of fully aromatic poly(ether ketone)s with macrocycle were successfully prepared by copolymerization of macrocycle of aryl ether ketone containing hydroxyphenyl groups, 4,4′‐(hexafluoroisopropylidene)diphenol (HFBPA), and 4,4‐difluorobenzophenone. The obtained copolymers have high molecular mass, good solubility, and high glass transition temperatures in the presence of CsF, the crosslinking reaction of copolymers occurred and afforded fully aromatic thermoset poly(aryl ether ketone)s by ring‐opening reaction driven by entropy. After crosslinking, these copolymers show much higher glass transition temperatures, excellent thermal stability, and better mechanical strength. © Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 7002–7010, 2008  相似文献   

5.
Porous poly(aryl thioether)s offer stability and electronic tunability by robust sulfur-aryl conjugated architecture, but synthetic access is hindered due to limited control over the nucleophilic nature of sulfides and the air sensitivity of aromatic thiols. Here, we report a simple, one-pot, inexpensive, regioselective synthesis of highly porous poly(aryl thioether)s through polycondensation of perfluoroaromatic compounds with sodium sulfide. The unprecedented temperature-dependent para-directing formation of thioether linkages leads to a stepwise transition of the polymer extension into a network, thereby allowing fine control of the porosity and optical band gaps. The obtained porous organic polymers with ultra-microporosity (<1 nm) and sulfur as the surface functional groups show size-dependent separation of organic micropollutants and selective removal of mercury ions from water. Our findings offer easy access to poly(aryl thioether)s with accessible sulfur functionalities and higher complexity, which will help in realizing advanced synthetic designs in applications such as adsorption, (photo)catalysis, and (opto)electronics.  相似文献   

6.
Novel poly(arylene thioether)s were synthesised using the one pot polymerisation method from the bis(N,N-dimethyl-S-carbamate) of 2,2-bis(4-mercaptophenyl)propane and activated difluoro aromatic compounds. Each of the polymers, obtained in good yields and with fairly high molecular weights, were characterised by IR, GPC and NMR analyses. In particular, the NMR characterisation was performed using 1H NMR, 13C NMR, DEPT, 2D COSY and 2D HSQC experiments. To study the effect on the thermal properties of replacing the ethereal oxygen atoms with sulfur atoms, we have synthesised the counterparts, the poly(arylene ether)s, with similar molecular weights. We observed that the substitution of the ethereal oxygen atoms with sulfur atoms results in a slightly lower thermal stability for the poly(thioether ketone)s, both under nitrogen and in air, and does not modify the Tg values. For the poly(thioether sulfone), on the other hand, the thermal stability is equal to that of the poly(ether sulfone), while the Tg is 10 °C lower. Furthermore, each sample is completely amorphous, with the exception of one of the poly(thioether ketone)s (sample 1b), which shows the capacity to crystallise, even if with a very slow crystallisation kinetics.  相似文献   

7.
动态力学分析技术(DMA)是研究聚合物性能的重要方法之一.动态力学实验可以检测聚合物的玻璃化转变温度和次级松弛过程,直接与聚合物的链结构和聚集态结构密切相关,聚合物的化学组成、支化和交联、结晶和取向、增塑和共混等结构因素的变化,都与分子运动状态的变化密切相关,而分子运动的变化又能灵敏地反映在动态力学性能上,  相似文献   

8.
Two series of novel amorphous poly(aryl ether phthalazine)s have been prepared via an intramolecular ring closure reaction of poly(aryl ether ketone)s (PAEKs) with hydrazine monohydrate. Fluorinated PAEKs, which display solubility in solvents incorporating a ketone functionality such as acetone or ethyl acetate, were converted to poly(aryl ether phthalazine)s to observe if these polymers would display similar solubility characteristics. The poly(aryl ether phthalazine)s have glass transition temperatures in the range of 278–320°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. The fluorinated poly(aryl ether phthalazine)s were not soluble in ketonic solvents. A series of poly(aryl ether phthalazine)s incorporating pendant 2-naphthalenyl moieties has been prepared in an attempt to produce amorphous, thermally stable polymers with high glass transition temperatures. The polymers have glass transition temperatures in the range of 287–334°C and show 5% weight loss points greater than 500°C in air and nitrogen atmospheres. Poly(aryl ether phthalazine)s undergo an exothermic reaction above the glass transition temperature. The major product of this reaction is a rearrangement of the phthalazine moieties to quiazoline moieties, however some crosslinking of the polymers occurs. Cured samples of the poly(aryl ether phthalazine)s show a small increase in the polymer Tg and are insoluble in all solvents tested. © 1996 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 34:1897–1905, 1996  相似文献   

9.
The synthesis of N-phenyl phthalazinium salts by condensation of a 1,2-diaroylbenzene with phenylhydrazine is described. This reaction was utilized to prepare novel poly(aryl ether phthalazinium) ionomers by the direct condensation of poly(aryl ether ketone)s with phenylhydrazine. The preparation of poly(aryl ether phthalazinium) ionomers by methylation of poly(aryl ether phthalazine)s is also described. Most of the ionomers are amorphous, thermally stable, and soluble in organic solvents. They can be cast into flexible and strong films. The glass transition temperature of the ionomers ranges from 297 to 363°C, an increase of 12 to 100°C over the corresponding neutral polymers. © 1996 John Wiley & Sons, Inc.  相似文献   

10.
It is shown that amine-terminated poly(aryl ether ketone)s based on the reaction of 4,4'-difluorobenzophenone, and a substituted hydroquinone [either methylhydroquinone (MePK), t-butylhydroquinone (tBPK), or phenylhydroquinone (PhPK)] of controlled molecular weight and high amine-termination efficiency can be synthesized by a two-step reaction technique. Attempts to synthesize analogous materials by a one-step method were shown to be unsuccessful. The side groups are shown to have a large influence on the aromatic proton chemical shifts and this effect is characterized. The side groups and molecular weight are also shown to influence the thermal transitions of the respective polymers. The tBPK polymer possessed the highest glass transition temperature, while the MePK polymer was found to be the only semi-crystalline polymer; a unit cell is proposed. The side groups and molecular weight effects are also characterized as a function of thermal stability and mechanical properties. © 1994 John Wiley & Sons, Inc.  相似文献   

11.
The molecular structure and polarizabilities of poly(aryl ether ketone)s were investigated with quantum chemical calculations, based on the fully optimized structures of model compounds (S5: ArCOArOArOArCOAr and BS6: ArOArCOArArCOArOAr) for their chain segments. The results showed that the average dihedral angle between their aromatic rings was in the range of 36°−37° relative to the molecular zig-zag plane. Especially, when a biphenyl group was introduced into the molecular chain of this polymer, its two aromatic rings were distorted by 48.0° to each other. Also, the calculation results of refractive indices for pure crystals obtained by using the structural parameters were in good accordance with those reported in the literature.  相似文献   

12.
Aromatic poly(arylene thioether)s were synthesized from N‐propyl‐S‐carbamate‐protected aromatic dithiols and aromatic difluorides. The deprotection of the protected dithiols with an organic base such as 1,8‐diazabicyclo[5.4.0]‐7‐undecene at room temperature and subsequent polymerization with the difluoride monomers at 120 °C in N‐methyl‐2‐pyrrolidinone produced high molecular weight polymers with intrinsic viscosities as high as 0.45 dL/g. The use of organic bases instead of inorganic bases for the generation of thiophenoxide nucleophile was a convenient way of avoiding metallic impurities in the synthesis of the poly(arylene thioether)s through a nucleophilic aromatic substitution reaction. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 43: 2021–2027, 2005  相似文献   

13.
High molecular weight poly(arylene thioether)s containing trifluoromethyl groups were prepared through the aromatic nucleophilic nitro‐displacement reaction of a dinitro monomer with aromatic dithiols. The high reactivity of the monomer, 4,4′‐dinitro‐3,3′‐bis(trifluoromethyl)biphenyl(1), activated by o‐trifluoromethyl groups and complete exclusion of oxygen was critical for the successful polymerization without any disulfide formation. The resulting trifluoromethylated poly(arylene thioether)s ( P1 and P2 ) were amorphous, dissolved in common organic solvents, and showed superior thermal properties compared to commercial poly(phenylene sulfide). © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 2440–2447, 2006  相似文献   

14.
A general method for the preparation of poly(aryl ether amide)s has been developed where the generation of an aryl ether linkage is the polymer-forming reaction. The amide linkage was found to be sufficiently electron-withdrawing to activate halo-substituents towards nucleophilic aromatic substitution analogous to conventional activating groups (i.e., sulfone, ketone, etc.). Model reactions demonstrated that the amide-activated displacement occurred with high selectivity in near quantitative yield and was judged suitable as a polymer-forming reaction. Appropriately fluoro-substituted amides were prepared and subjected to displacement polymerization with bisphenoxides in a N-methyl-2-pyrrolidone (NMP)/N-cyclohexyl-2-pyrrolidone (CHP) solvent mixture. High molecular weight polymers with glass transition temperatures in the 200–225°C range were obtained. © 1993 John Wiley & Sons, Inc.  相似文献   

15.
A series of poly(aryl amine ketone)s have been obtained by the condensation polymerization of different aromatic dibromides with different primary aromatic diamines via palladium-catalyzed aryl amination reaction. The structures of polymers are characterized by means of FT-IR, 1H NMR spectroscopy, and elemental analysis. The results show an agreement with the proposed structures. DSC and TG measurements show that polymers possess high glass transition temperature (Tg>170℃) and good thermal stability with high decomposition temperatures (TD>450℃). These novel polymers also exhibit good mechanical behaviors and good solubility.  相似文献   

16.
A series of poly(aryl ether)s were successfully prepared via aromatic nucleophilic substitution reaction from various bisphenols and a novel bipolar aryl difluoride monomer containing electron‐donor triphenylamine and electron‐acceptor 1,2,4‐triazole moieties. The poly(aryl ether)s exhibited excellent solubility in organic solvents such as dimethylformamide, chloroform, and tetrahydrofuran at room temperature. The poly(aryl ether)s showed high thermal stability with Td10 higher than 500 °C and glass transition temperatures (Tg) higher than 187 °C. The thin films of the poly(aryl ether)s indicated bistable resistive switching behavior with ON/OFF current ratios as high as 103. The switching on and switching off bias voltages of the poly(aryl ether)s were affected by the bisphenol moiety. The good resistive switching behavior of the poly(aryl ether)s made them promising candidates for future nonvolatile memory applications. © 2008 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 46: 6861–6871, 2008  相似文献   

17.
聚芳醚酮树脂的分子设计与合成及性能   总被引:1,自引:0,他引:1  
聚芳醚酮树脂是20世纪发展起来的重要特种工程塑料.因其优良的耐热、耐腐蚀、耐摩擦及生物相容性好等特点,在国防军工、武器装备、航空航天、电子、汽车、机械、石油工业、核能及理疗卫生等高技术领有广泛的应用.此类材料大都采用双酚单体和双氟单体通过A2+B2型亲核缩聚反应制备.这类聚合物的分子结构对材料的性能影响较大,一般情况下分子链由醚、酮、苯三元规整结构构成时,聚合物为半结晶态;然而,当分子结构中存在侧基或其他非规整结构往往破坏聚合物的结晶结构,聚合物呈现无定型态.半结晶聚芳醚酮聚合物具有非常优异的耐热、耐化学稳定性一般作为结构型材料使用;无定型聚芳醚酮具有良好的加工性能,并且可进行一些功能化成为一类优异的功能型材料.本文从结构与性能关系出发,介绍了聚芳醚酮树脂种类,聚芳醚酮树脂的发展历程及合成方法;探讨了聚芳醚酮材料结构与性能关系;总结了功能性聚芳醚酮材料的前沿进展;最后结合实际展望了聚芳醚酮的应用发展方向.  相似文献   

18.
A series of macrocyclic aryl ketone oligomers were prepared by the reaction of phthaloyl dichloride or isophthaloyl dichloride with various bridge‐linking electron‐rich aromatic hydrocarbons 3a–d under pseudo‐high dilution conditions in the presence of Lewis base via Friedel–Crafts acylation reaction. Detailed structural characterization of these oligomers confirmed the cyclic nature by a combination of MALDI‐TOF‐MS, GPC, and 1H NMR analyses. These cyclic ketone oligomers have high solubility in organic solvents and the cyclic oligomers derived from phthaloyl dichloride are amorphous. The cyclic ketone oligomers readily undergo anionic ring‐opening polymerization in the melt by using potassium 4,4′‐biphenoxide as the initiator, producing linear, high molecular weight poly(ether ketone)s. Moreover, the isothermal chemorheology of the ring‐opening polymerization of cyclic oligomers 4a and 4b was also investigated. The results show that the shear viscosity of the molten reactive mixture is lower than 10 Pa · S at a constant shear rate of 0.05 rad/sec and increases slowly in the initial stage of ring‐opening polymerization. Copyright © 2009 John Wiley & Sons, Ltd.  相似文献   

19.
A convenient method for the synthesis of poly(1,3,4-oxadiazole)s of high molecular weights has been developed. These polymers were prepared readily by the direct polycondensation of dicarboxylic acids with hydrazine sulfate ( 1 ) using phosphorus pentoxide/methanesulfonic acid (PPMA) as both a condensing agent and solvent. Polycondensation of aliphatic dicarboxylic acids with 1 proceeded even at room temperature and produced poly(1,3,4-oxadiazole)s with inherent viscosities up to 1.4 dL/g. The synthesis of aromatic poly(1,3,4-oxadiazole)s from aromatic dicarboxylic acids containing phenyl ether structures was carried out by a one-pot procedure because the preactivation of dicarboxylic acids was required. The synthesis of 2,5-disubstituted-1,3,4-oxadiazoles by the reaction of carboxylic acids with 1 in PPMA was studied to demonstrate the feasibility of the reaction for polymer formation. The thermogravimetry of the aromatic poly(1,3,4-oxadiazole)s showed 10% weight loss both in air and in nitrogen at 440–490°C.  相似文献   

20.
聚芳醚酮由于熔融粘度大和加工温度高而影响了其进一步工业化,因此降低熔融粘度和加工温度是研究聚芳醚酮的新课题[1].目前在工程塑料中热致液晶高分子是一种具有低熔融粘度而性能优异的材料,其熔融粘度比一般高分子材料低得多,并且具有优异的机械性能[2]本文采用无现...  相似文献   

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