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1.
The influence of isomerism of difluorobenzophenone on the efficiency of polycondensation and the properties of homo- and copoly(arylene ether ketones) was studied. The latter were prepared by the reaction of 2,4"- and 4,4"-difluorobenzophenone with potassium diphenolates of bisphenol À and phenolphthalein in N,N-dimethylacetamide. A high content of an admixture of the 2,4"-isomer in 4,4"-difluorobenzophenone decreases the molecular weight of related poly(arylene ether ketones) and has no substantial effect on their glass transition temperature.  相似文献   

2.
A series of novel poly(arylene ether ketone)s were synthesized from the reaction of hydroquinone and 4-(4-hydroxyphenyl)-2,3-phthalazin-1-one with 4,4′-difluorobenzophenone in N-cyclohexylpyrrolidinone containing anhydrous potassium carbonate. The polymers exhibited high glass transition temperatures together with excellent thermooxidative stability. The chain structure of these polymers was studied by means of differential scanning calorimetry (DSC), wide-angle X-ray diffraction techniques (WAXD), and matrix-assisted laser desorption/ionization time of flight mass spectrometry (MALDI-TOF-MS). The experimental results indicated that these “as-made” copoly(aryleneketone)s containing hydroquinone moieties exhibited a block chain structure with segments which mainly consisted of hydroquinone and 4,4′-difluorobenzophenone. These chain segments resulted in crystallites in the polymers although they are thermodynamically unstable. The polymers showed thermal properties comparable to commercial PEEK, but the conditions for synthesis are much milder. The glass transition temperatures and solubilities of the copoly(arylene ketone)s tended to increase with increasing phthalazinone moiety content, while the crystallite melting points and crystallinity appeared to decrease. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1781–1788, 1999  相似文献   

3.
The polycondensation of 2-β-oxyethyl-3,3-bis(4-oxyphenyl)phthalimidine with 4,4′-difluorobenzophenone proceeding via the nucleophilic substitution of the activated halogen atom in aryl halide has been studied. Conditions ensuring formation of noncrosslinked high-molecular-mass homo- and copoly(arylene ether ketones) containing side alcoholic hydroxyl groups (4,4′-difluorobenzophenone: a mixture of bisphenols: K2CO3: Na2CO3 = 1: 1: 1: 0.05) have been established. The polymers have M w = (20–88.7) × 103 and show good solubility in organic solvents; their onset temperatures of softening are in the range 195–250°C. Polymer films cast from solution are characterized by a breaking strength of 78–109 MPa.  相似文献   

4.
Russian Journal of General Chemistry - The article presents data on the synthesis and properties of amorphous random cardo copoly(arylene ether ketones), obtained by polycondensation by the...  相似文献   

5.
We present a series of novel poly(arylene ether sulfone) copolymers containing pendant oligoaniline groups. A novel monomer containing oligoaniline, 2,6‐difluorobenzoyl aniline tetramer (DFAT), was synthesized by reaction of 2,6‐difluorobenzoyl chloride and parent aniline tetramer and incorporated into the aforementioned copolymers via direct copolymerization with 4,4′‐dichlorodiphenyl sulfone (DCDPS), and 4,4′‐isopropylidene diphenol (BPA) using N,N′‐dimethylacetamide as solvent. The structures of these copolymers were confirmed by FTIR, 1H NMR, and GPC. Spectral analysis of the copolymers in different oxidation states was investigated via UV‐visible spectra. The copolymers exhibited outstanding thermal stability and good solubility in various organic solvents. Their electroactivity, explored with cyclic voltammetry, was found to increase as the content of oligoaniline in the polymer increased. The electric and dielectric properties of the copolymers were also studied in detail. The electrochromic performance of the copolymers was investigated by electrochromic photographs and transmittance spectra; the color of the copolymer thin films changes from grey (at 0.0 V), to green (at 0.4 V), to blue (at 0.6 V) and to pearl blue (at 1.0 V) and the maximum transmittance change (ΔT) at 700 nm is 42.6% (90.7% ? 48.1%). © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011  相似文献   

6.
The proton conductivity of films based on sulfonated poly(arylene ether ketone) derived from bisphenol A and 4,4′-difluorobenzophenone of various modification degrees has been studied. The conductivity achieves high levels upon incorporation of a large amount of sulfo groups into the polymer. The conductivity of the samples with low sulfonation degrees may be increased via introduction of the nanodisperse zirconium acid sulfate additive.  相似文献   

7.
以4,4'-二氟二苯砜,4,4'-联苯二酚及1,5-二氯蒽醌为原料,采用亲核缩聚方法将具有良好热稳定性的蒽醌生色团分子以共价键方式引入到聚芳醚砜体系中,制备出了蒽醌含量分别为10%、20%及30%的热分解温度在500℃以上的新型耐高温有机高分子染料.该系列聚合物具有较高的分子量和良好的溶解性.利用红外光谱(FTIR)、核磁共振(1H-NMR)等表征方法确定了聚合物的结构;利用紫外-可见光谱测试(UV-Vis)初步研究了聚合物的光谱学特性;利用差示扫描量热测试(DSC)和热失重分析测试(TGA)研究了聚合物的热性能.  相似文献   

8.
Macrocyclic arylene ether ketone dimer was isolated from a mixture of cyclic oligomers obtained by the nucleophilic substitution reaction of bisphenol A and 4,4′-difluorobenzophenone and easily polymerized to high molecular weight linear poly-(ether ketone). The cyclic compound was characterized by FTIR, 1H- and 13C-NMR, and single-crystal x-ray diffraction. Analysis of the spectral and crystal structure reveals extreme distortions of the phenyl rings attached to the isopropylidene center and of the turning points of the molecular polygons. The release of the ring strain on ring-opening combined with entropical difference between the linear polymer chain and the more rigid macrocycle at temperatures of polymerization may be the proposed motivating factors in the polymerization of this precursor to high molecular weight poly(ether ketone). © 1997 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 35 : 1753–1761, 1997  相似文献   

9.
A series of copoly(ether ketone)s containing double bonds along the polymer chains were synthesized from the condensation polymerization of hydroquinone with 4,4′‐difluorobenzophenone and 4,5‐bis(4‐fluorobenzoyl)‐1‐methylcyclohexene in sulfolane containing anhydrous potassium carbonate. The presence of methylcyclohexene in the polymer chains resulted in an improvement in the solubility of poly(ether ketone)s in organic solvents such as chloroform, chlorobenzene, and sulfolane. As a result, the conditions for synthesizing these polymers were much milder than those for poly(ether ether ketone). The new copoly(ether ketone)s also showed good tensile properties and reasonable thermal stability. New polyethers containing pyrazine unites were obtained from the cyclization reaction of these copoly(ether ketone)s with hydrazine. The hydrazine cycloderivatives led to an increase in the glass‐transition temperatures and a decrease in solubility in organic solvents. © 2002 Government of Canada. Exclusive world‐wide publication rights in the article have been transferred to Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 40: 3449–3454, 2002  相似文献   

10.
A number of copoly(arylene ether ketones) containing the phenolfluorene and bisphenol A fragments were synthesized. By the example of these compounds, it was shown for the first time that the effect of reversible electronic switching can exhibit in the copolymer films even if this effect is absent in the corresponding homopolymer films.  相似文献   

11.
以1,4-双-(4’-溴苯酰基)苯和2,2-双-[4-(4-氨基苯氧基)苯基]丙烷为单体,以三(二亚苄基丙酮)二钯为催化剂,1,1’-联萘-2,2’-二苯膦(BINAP)为配体,由钯催化的胺基化反应缩聚合成了含异亚丙基的聚亚胺醚酮(pr—PIEK),并通过微封装法制备了pr—PIEK空心微球.  相似文献   

12.
Summary: Poly(arylene ether sulfone)s of high molecular weight and narrow molecular weight distribution were obtained by melt polycondensation of 4,4′-difluorodiphenyl- sulfone and trimethylsilylethers of 4,4′-dihydroxydiphenylsulfone and phenylhydroquinone using CsF as catalyst. Although a block-like structure of the polymers could be expected from the course of reaction, only a single Tg ranging from 190 °C to 230 °C could be detected by DSC and which depended on the copolymer composition. Contrary to the sulfonation of similar poly(ether ether ketone)s the poly(arylene ether sulfone)s here reported were sulfonated both in the side chain and the main chain. Nonetheless the sulfonated poly(arylene ether sulfone)s showed high hydrolytic stability in water at 130 °C.  相似文献   

13.
The synthesis of a new A2X‐type difluoride monomer, N‐2‐pyridyl‐4′,4″‐bis‐(4‐fluorobenzenesulfonyl)‐o‐terphenyl‐3,6‐dimethyl‐4,5‐dicarboxylic imide ( 3 ), is described. The monomer 3 was incorporated into a series of copoly(aryl ether sulfone)s by polymerization of 4,4′‐isopropylidenediphenol and 4,4′‐difluorophenylsulfone. The incorporation of monomer 3 had an observable effect on both the glass‐transition temperature of poly(aryl ether sulfone)s and the tendency for macrocyclic oligomers to form during polymerization. Replacement of the pyridyl imide group via a transimidization reaction with propargyl amine proceeded quantitatively and without polymer degradation. The acetylene containing copoly(aryl ether sulfone) could be crosslinked by simple thermal treatment, resulting in an increase in the glass‐transition temperature and solvent resistance. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 9–17, 2000  相似文献   

14.
利用含溴苯侧基的聚芳醚砜(PES-Br)和1,1,2,2-四氟-2-(1,1,2,2-四氟-2-碘乙氧基)乙烷磺酸钾(PSA-K)进行Ullman偶联反应, 制备了新型含全氟磺酸侧链的聚芳醚砜(PES-PSA), 全氟磺酸的引入量为50%. 在离子交换容量(IEC)为0.907 meq./g, 80 ℃, 相对湿度为100%时, PES-PSA质子传导率达到0.039 S/cm, 表现出较高的质子传导能力. 其较低的IEC值使膜材料表现出良好的热稳定性和尺寸稳定性.  相似文献   

15.
A series of macrocyclic arylene ether ketone oligomers from 4,4′-difluorobenzophenone, 2,4′-difluorobenzophenone and 1,3-bis(4′-fluorobenzoyl)benzene were prepared via aromatic nucleophilic substitution according to the pseudo-high dilution principle. Small-size aromatic macrocycles were isolated by silica gel column chromatography with cyclohexane/ethyl acetate as eluent. The chemical structures of these small-size macrocycles were characterized by matrix-assisted laser desorption ionization–time-of-flight–mass spectrometry (MALDI–TOF–MS), IR, 19F-,1H-, and 13C-NMR, and GPC techniques. Molecular chain length and steric hindrance of monomers affected the product compositions. The NMR results show that there are different chemical shifts in the different ring-size macrocyclic poly arylene ether ketones in spite of having the same repeating unit. The crystallizability and thermal properties of small-size arylene ether ketone macrocycles were also investigated by DSC, WAXD, TGA, and the results suggest that the crystallization and thermal properties are related to their intrinsic chemical structures. © 1999 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 37: 1957–1967, 1999  相似文献   

16.
Comb-shaped poly(arylene ether ketones) containing hydrophilic fragments in side chains are synthesized through the interaction of side reactive carboxyl groups of poly(arylene ether ketones) with methyl ethers of poly(ethylene glycol). Films based on these polymers possess tensile strengths up to 89 MPa and relative elongations at break up to 340%. Comb-shaped poly(arylene ether ketones) swell in water, and some of them show solubility in ethanol and methanol.  相似文献   

17.
New poly(arylene ethers) containing side sulfo groups have been synthesized through the copolycondensation of 3,5-dinitrodiphenyl sulfone 4′-sulfonic acid and 4,4′-dichlorodiphenyl sulfone with bicyclic aromatic bisphenols under the conditions of aromatic nucleophilic substitution. On the basis of the blends of these copolymers with sulfonated poly(arylene ester ether ketone), membranes with satisfactory mechanical characteristics and high proton conductivity have been prepared.  相似文献   

18.
Several new random and block copoly(imide siloxane)s have been prepared by the solution polycondensation of commercially available 4,4′-oxydianiline (ODA) and amino-propyl terminated polydimethylsiloxane (APPS) with 4,4′-(hexafluoro-isopropylidene)diphthalic anhydride (6FDA). The siloxane loading was kept to 10, 20, 30, 40 and 50 wt% in the copolymers. The random copolymers were prepared by a one pot solution imidization technique, and two pot solution imidization technique was adopted for the synthesis of the block copolymers. The diamine ODA and the dianhydride 6FDA composed the hard block segment, while APPS and 6FDA composed the soft block segment. The hard block length was kept constant while the soft block lengths were varied by varying the siloxane loading. Accordingly, block copoly(imide siloxane)s were prepared on increasing the soft block lengths (DP) from 3 to 6, 10, 18 and 36 for fixed hard block length of 22. The resulting polymers have been well characterized by IR, NMR and GPC techniques. Thermal and mechanical properties of the random and block copolymers were compared with the already reported homopolyimide without siloxane moiety.  相似文献   

19.
In this work we present the results from studies on novel poly(arylene ether ketone)s, including gas permeability, wide-angle x-ray diffraction (WAXD), and dynamic mechanical analysis (DMA). Poly(arylene ether ketone)s containing 2,2′- and 3,3′-dibenzoylbiphenyl (DBBP) moieties were characterized to study the effect of biphenyl substitution on gas transport properties. Gas permeabilities of naphthalene-containing poly(arylene ether ketone)s were also measured. Higher permeabilities were observed for polymers prepared with 6F-BPA, compared to 9,9-bis(4-hydroxyphenyl)fluorene (HPF). The naphthalene-containing polymers exhibited higher permeabilities than the DBBP polymers, except for a polymer having the 2,2′-DBBP and tetramethylbiphenyl moieties. Based on our work, and results reported in the literature, the 3,3′-DBBP polymers showed the lowest permeabilities for DBBP-containing poly-(arylene ether ketone)s. The low permeabilities are due to more efficiently packed chains brought on by greater flexibility of the backbone, compared to the other polymers studied. DMA studies confirmed the higher barriers to rotation which are believed to be responsible for 2,2′-DBBP polymers having similar selectivities compared to 3,3′-DBBP polymers. © 1998 John Wiley & Sons, Inc. J Polym Sci B: Polym Phys 36: 425–431, 1998  相似文献   

20.
通过分子设计, 成功合成了一种含有三苯基膦结构的二氟单体--4,4’-二氟二苯苯磷氧(BFPPO). 在碱催化条件下, BFPPO与2-双-(4-羟苯基)六氟丙烷(六氟双酚A)缩聚得到一种新型含三苯基膦结构的聚芳醚材料(6F-PAEPO). 使用FTIR,1H NMR, 31P NMR, 和16F NMR等表征手段确定了聚合物的结构, 聚合物表现出良好的热稳定性、有机可溶性、机械性能和光透过性能, 其中聚合物的玻璃化转变温度高达211℃, 空气气氛和氮气气氛下5%热失重温度分别为512℃和523℃, 聚合物薄膜的最大光透过率超过80%. 尤其, 聚合物由于主链中三苯基磷氧结构的存在, 表现出了优异的阻燃性能, 有限氧指数(LOI)达到39.9%.  相似文献   

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