Synthesis and characterization of a novel AB2 monomer and corresponding hyperbranched poly(arylene ether phosphine oxide)s

A novel AB₂ monomer, 4‐(fluorophenyl)‐4′,4″‐(bishydroxyphenyl) phosphine oxide, was synthesized. The monomer was successfully polymerized to a modest molecular weight with various catalysts, including K₂CO₃ and Cs₂CO₃/Mg(OH)₂. Hyperbranched polymers exhibited exceptionally high thermal stability and solubility in conventional polar organic solvents and basic water solutions. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 3736–3741, 2000     

Linear and Hyperbranched Poly(arylene ether)s from a New Semifluorinated AB Monomer

A new trifluoromethyl-activated AB monomer has been successfully synthesized by Pd-initiated coupling of 4-bromo anisole with 4-fluoro-3-trifluoromethylphenylboronic acid followed by demethylation. The monomer leads to a semifluorinated poly(arylene ether) by nucleophilic displacement polymerization reaction. The AB monomer has been further copolymerized with a corresponding AB ₂ monomer to form the corresponding semifluorinated hyperbranched (hb) poly(arylene ether). The resulting linear and hb poly(arylene ether)s exhibited weight average molecular weight of 75700 and 144100 g/mol, respectively. The hb copolymer exhibited better solubility in different organic solvents compared to the linear poly(arylene ether). The polymers showed excellent thermal stability up to 522°C at 10% wt loss in air and glass transition temperatures as high as 187°C. The mechanical properties of the linear poly(arylene ether) film 1a exhibited tensile strength at break of 89 MPa, elongation at break of up to 3% and a Young’s modulus value of 2.66 GPa. The films of the polymers were hydrophobic in nature and showed water contact angle as high as 93.6°.     

新型含磷双酚A型共聚醚醚酮的合成与性能

新型含磷双酚A型共聚醚醚酮的合成与性能;溶液缩聚;含磷单体     

Synthesis and characterization of new hyperbranched poly(aryl ether oxadiazole)s

A new AB₂ monomer was synthesized for use in the preparation of a hyperbranched poly(aryl ether oxadiazole) with terminal phenol functionality. The AB₂ monomer contains two phenolic groups and a single aryl fluoride group that is activated toward nucleophilic displacement by the attached oxadiazole ring. The nucleophilic substitution of the fluoride with the phenolate groups led to the formation of an ether linkage. Subsequently, a hyperbranched poly(aryl ether oxadiazole) having approximately a 44% degree of branching, as determined by a combination of model compound studies and ¹H NMR, was obtained. The terminal phenolic groups underwent facile functionalization, furnishing hyperbranched polymers with a variety of functional chain ends. The nature of the chain‐end groups had a significant influence on the physical properties of the polymers, such as the glass‐transition temperature and their solubility. © 2001 John Wiley & Sons, Inc. J Polym Sci Part A: Polym Chem 39: 3851–3860, 2001     

含异亚丙基聚亚胺醚酮空心微球的制备

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．     

Side-Chain Sulfonated Poly(arylene ether)s for Fuel Cell Applications

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 T_g 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.     

质子交换膜用磺化聚芳醚的合成与性能研究

合成了一种用于质子交换膜的新型磺化聚芳醚. 由于特殊单体结构的设计, 在聚合物主链上引入取代基对主链进行保护, 用氯磺酸直接磺化方法在聚芳醚高分子侧基上引入磺酸功能基, 实现了聚合物磺化结构的可控定位合成, 得到了稳定性较好的磺化聚芳醚. 用溶液浇膜法制备了质子交换膜, 考察了质子交换膜的各种性能. 结果表明, 这种膜具有良好的成膜性, 水解性稳定性和优异热稳定性能, 5%的热失重温度为362.3 ℃. 氧化稳定性在80 ℃的Fenton’s试剂(3%的过氧化氢和2 mg/L的FeSO₄)中进行, 膜在69 min时才开始变碎, 表现出良好的氧化稳定性.     

3种新型聚苯基醚喹噁啉的合成

用4,4′-二氟代二苯甲酰与双酚A的溶液缩聚制得聚醚苯偶酰(PEB),经邻苯二胺改性后,通过两步法得到聚苯基醚喹噁啉（PEQ-1）。 在PEB的改性反应中加入质量分数分别为1.0%和1.3%的3,3′,4,4′-四胺基二苯醚,可有效增加聚苯基醚喹噁啉的相对分子质量,得到PEQ-2和PEQ-3（总收率≥90%）,其质均相对分子质量分别为7.492×104和1.486×105。 并用IR、 NMR等对这些聚合物进行了表征。 该法操作简便,具有潜在的应用价值。     

Controlled sulfonation of poly(arylene ether sulfone)s and poly(arylene ether ketone)s with different molecular structures for polymer electrolyte membranes

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.     

Poly(arylene ether)s,poly(arylene thioether)s,and poly(arylene sulfone)s derived from a dihydroxy(imidoarylene) monomer

Novel poly(arylene ether)s, poly(arylene thioether)s, and poly(arylene sulfone)s were synthesized from the dihydroxy(imidoarylene) monomer 1 . The syntheses of poly(arylene ether)s were carried out in DMAc in the presence of anhydrous K₂CO₃ by a nucleophilic substitution reaction between the bisphenol and activated difluoro compounds. Poly(arylene thioether)s were synthesized according to the recently discovered one-pot polymerization reaction between a bis(N,N′-dimethyl-S-carbamate) and activated difluoro compounds in the presence of a mixture of Cs₂CO₃ and CaCO₃. The bis(N,N′-dimethyl-S-carbamate) 3 was synthesized by the thermal rearrangement reaction of bis(N,N′-dimethylthiocarbamate) 2 , which was synthesized from 1 by a phase-transfer catalyzed reaction. The poly(arylene thioether)s were further oxidized to form poly(arylene sulfone)s, which would be very difficult, if not impossible, to synthesize by other methods. All of the polymers described have extremely high T_gs and thermal stability as determined from DSC and TGA analysis. Poly(arylene sulfone)s have the highest T_gs and they are in the range of 298–361°C. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1201–1208, 1998     

新型聚醚聚氨酯/硬段模型化合物/高氯酸钠复合物的制备和表征

以聚醚聚氨酯和硬段模型化合物为聚合物基体,高氯酸钠为掺杂盐,合成了一系列新型的聚氨酯／硬段模型化合物／高氯酸钠复合物,利用FR－IR,DSC,AFM和复阻抗谱等表征手段对其形态和性能进行了基团和羰基都可与钠离子进行络合,温度变化可以导致不同程度的络合,在低盐浓度下,复合物的Tk随盐浓度的增加逐渐上升,而在一定的浓度之上,玻璃化转变温度又明显下降;通过调整盐的含量可以得到不同的表面形态。随着温度的升高,该体系的离子电导率显著增加。     

A Kinetic Study of the Thermal and Oxidative Degradations of a New Poly(arylene)ether Copolymer

The degradation of a new thermoplastic poly(arylene)ether copolymer was carried out in both dynamic and isothermal heating conditions, under nitrogen flow and in a static air atmosphere. The measurements showed that the copolymer degraded through two stages in both investigated environments with the formation of a stable residue in N₂ and complete mass loss in air. The apparent activation energy values associated with the degradation processes were evaluated. The obtained results suggested different degradation mechanisms between N₂and air. Results were discussed and compared with those obtained for several polymers previously investigated. This revised version was published online in July 2006 with corrections to the Cover Date.     

Miscibility Behaviour of Poly(ether Sulphone)/nylon-6 Blends

Binary blends of poly (ether sulphone) (PES) and Nylon-6 were prepared in a whole range of composition by melt extrusion. Miscibility behaviour of the blends were studied using thermal analytical techniques like differential scanning calorimetry (DSC) and dynamic mechanical analysis (DMA). Due to the rapid crystallization of Nylon-6 as it is cooled from the melt state, its glass transition behaviour could not be detected even in the quenched samples by DSC. Furthermore, the crystallization and melting behaviour of the blends have been studied by DSC. DMA results show that the dynamic storage modulus of the blends were in-between those of the constituent polymers. Also the glass transition of Nylon-6 phase as determined by the peak in loss tangent remains constant which shows that the two polymers are immiscible. Thermal expansion coefficient of the blends as determined by TMA is greater than that of Nylon-6 signifying the increased dimensional stability of the blends at higher temperatures. Morphological studies done by scanning electron microscopy (SEM) show the biphasic nature of the blends, with clear cut boundaries between the phases because of poor interfacial adhesion. Dispersed particle size is small when Nylon-6 is the dispersed phase because of its lower melt viscosity as compared to PES. Thermal stability of the blends was measured using thermogravimetric analysis (TG). Two-step decomposition behaviour was observed because of macro-phase separated morphology. This revised version was published online in July 2006 with corrections to the Cover Date.     

Synthesis and characterization of hyperbranched aromatic poly(ether imide)s with terminal amino groups

We synthesized an AB₂‐type monomer, 4‐{4‐[di(4‐aminophenyl)methyl]phenoxy}phthalic acid, which contained one phthalic acid group and two aminophenyl functionalities. The direct self‐polycondensation of the AB₂‐type monomer in the presence of triphenylphosphite as an activator afforded a hyperbranched poly(ether imide) with a large number of terminal amino groups. This polymer was characterized with ¹H NMR and IR spectroscopy. The degree of branching of the hyperbranched poly(ether imide) was approximately 56%, as determined by a combination of model compound studies and an analysis of ¹H NMR spectroscopy integration data. The terminal amino groups underwent functionalization readily. The solubility and thermal properties of the resulting polymers depended on the nature of the chain end groups. In addition, the hyperbranched poly(ether imide) was grafted with polyhedral oligomeric silsesquioxane (POSS). Transmission electron microscopy analysis revealed that the grafted POSS molecules aggregated to form a nanocomposite material. © 2003 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 41: 3726–3735, 2003     

Anion Exchange Membranes Based on Chloromethylation of Fluorinated Poly(arylene ether)s

This report details the properties of fluorine-containing anion exchange membranes(AEMs) synthesized by chloromethylation and quaternization of fluorinated poly(arylene ether)s(FPAEs) based on decafluorobiphenyl and bisphenol A. Meanwhile, we compared their properties with those of their non-fluorinated counterparts, Udel-based AEMs. The reactivity of the chloromethylation of fluorinated poly(arylene ether)s was lowered by the strong electron-withdrawing group, per-fluorinated biphenyl residue. Therefore higher temperature, more chloromethylation reagent, and longer reaction time were needed in the chloromethylation of FPAEs. Because of the hydrophobicity of fluorine, the swelling of FPAEs was depressed. In the FPAE-based AEMs, the water uptake of FPAE-1 membrane(F-1) was just 30%. There is a strong correlation between water uptake and conductivity for both Udel- and FPAE-based AEMs. Among all the membranes, the water uptake and the conductivity of FPAE-3 membrane(F-3) could reach up to 100% and 13.47 mS/cm respectively at 30 ℃. The mechanical properties of FPAE-based AEMs at room temperature were worse than those of Udel-based ones because of the weak intermolecular interaction caused by the low polarizability of fluorine. However, their high temperature mechanical properties are better, which can be explained in terms of low swelling.     

Synthesis and Adsorption Property of Two Polymeric Adsorbents with Pendent Ether Bonds

Two polymeric adsorbents, poly(methyl p-vinylbenzvl ether) and oolv(ohenvl p-vinylbenzyl ether), were synthesized from chloromethylated polystyrene, Their adsorptionproperty for phenol in hexane solution was investigated. The results showed that the twoadsorbents adsorb phenol from hexane solution through hydrogen-bonding and π-π stacking interaction.     

Synthesis and characterization of new poly(arylene ether)s containing heterocyclic units. II.

A series of new poly(arylene ether)s, containing naphthalene, pyridine, and quinoline units have been prepared by solution condensation polymerization. The synthesis involves nucleophilic displacement of aromatic dihalides with aromatic potassium bisphenates in an anhydrous dipolar aprotic solvent at elevated temperatures. The polymers, having inherent viscosity from 0.24 to 1.32 dL/g, were obtained in quantitative yield, have excellent thermal stability as shown by 10% weight loss temperatures in nitrogen and air (above 450 and 430°C, respectively) and high glass transition temperatures (in the range of 150–220°C). The introduction of quinoline moieties in the polymer backbone positively influences the thermal properties, such as high T_g/T_m ratios. © 1995 John Wiley & Sons, Inc.     

Hydrophilic Films Based on Blends of Poly(acrylic acid) and Poly(2‐hydroxyethyl vinyl ether): Thermal,Mechanical, and Morphological Characterization

Hydrophilic films based on blends of poly(acrylic acid) and poly(2‐hydroxyethyl vinyl ether) were prepared by casting. The characterization of the films was performed by differential scanning calorimetry (DSC), dynamic mechanical thermal analysis (DMTA), and scanning electron microscopy (SEM). It was shown that an increase of poly(2‐hydroxyethyl vinyl ether) content in the blends considerably decreases the glass transition temperature of the samples. The films containing 10 and 20 mol‐% of poly(2‐hydroxyethyl vinyl ether) show behavior of polymers in the glassy state, but a further increase of nonionic polymer content in the blend (30–50 mol‐%) provides the mechanical properties typical of a rubbery state. The content of water traces in the films has a significant effect on the mechanical properties of the materials.

Normalized DSC thermograms of PAA:PHEVE films. [PAA]:[PHEVE] = 90:10 (1), 80:20 (2), 70:30 (3), 60:40 (4), 50:50 mol‐% (5).     

多磺化侧链型聚芳醚的合成及性能

本文通过对聚合物的结构设计,采用亲和取代的途径制备了含有甲氧基侧链的聚芳醚聚合物,然后去醚化得到了侧链含有羟基的聚芳醚材料,最后通过接枝的方法将磺酸基团引入聚合物成功的制备出多磺化侧链型聚芳醚质子交换膜材料。此类材料表现出好的热化学稳定性, 80 oC时的质子传导率可达到0.192 S/cm,超过了Nafion 117 薄膜的传导率.同时此类材料表现出低的尺寸稳定性。因此此类材料很有希望在质子交换膜领域得到应用     

Synthesis and characterization of poly(itaconate ester)s with etheric side chains

The synthesis and characterization of poly(itaconate ester)s with short poly(ethylene oxide) side chains have been studied. It was found that the monomer syntheses via esterification of itaconic acid resulted in incomplete esterification leaving up to 35 mol % monomers with carboxylic acid functionality. These acid groups were then incorporated into the polymers. This acid incorporation has not previously been reported, nor have the properties of the copolymers been studied. Techniques were developed to effectively remove the acid impurities to generate pure homopolymers. Titration and gas chromatographic techniques were developed to study the amount of acid impurity in the monomers, and titration was also used to characterize the polymers. Size exclusion chromatography and differential scanning calorimetry were used to study both the homopolymers and copolymers. It was found that the location and breadth of the glass transition is a function of acid content. Finally, isomerization of the itaconate monomers to the inactive mesaconate was also found to be a problem during the synthesis. Pure mesaconate and citraconate monomers were synthesized and characterized by ¹H-NMR. © 1993 John Wiley & Sons, Inc.