24 resultados para Flor do cardo

em Chinese Academy of Sciences Institutional Repositories Grid Portal


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A new class of polymeric amine, namely, sulfonated cardo poly(arylene ether sulfone) (SPES-NH2) was synthesized and used for the preparation of thin-film composite membrane. The TFC membranes were prepared on a polysulfone supporting film through interfacial polymerization with trimesoyl chloride (TMC) solutions and amine solutions containing SPES-NH2 and m-phenylenediamine (MPDA). The resultant membranes were characterized with water permeation performance, chemical structure, hydrophilicity of active layer and membrane morphology including top surface and cross-section.

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Novel bisphenol monomers (1a-d) containing phthalimide groups were synthesized by the reaction of phenolphthalein with ammonia, methylamine, aniline, and 4-tert-butylanilne, respectively. A series of cardo poly (arylene ether sulfone)s was synthesized via aromatic nucleophilic substitution of 1a-d with dichlorodiphenylsulfone, and characterized in terms of thermal, mechanical and gas transport properties to H-2, O-2, N-2, and CO2. The polymers showed high glass transition temperature in the range 230-296 degrees C, good solubility in polar solvents as well as excellent thermal stability with 5% weight loss above 410 degrees C. The most permeable membrane studied showed permeability coefficients of 1.78 barrers to O-2 and 13.80 barrers to CO2, with ideal selectivity. factors of 4.24 for O-2/N-2 pair and 28.75 for CO2/CH4 pair. Furthermore, the structure-property relationship among these cardo poly(arylene ether sulfone)s had been discussed on solubility, thermal stability, mechanical, and gas permeation properties. The results indicated that introducing 4-tert-butylphenyl group improved the gas permeability of polymers evidently.

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Gas transport of H-2, CO2, O-2, N-2, and CH4 in a series of cardo polyarylethers were examined over a temperature range of 30 similar to 100 degreesC. These polymers include three poly(aryletherketone)s, two poly(arylethersulfone)s, and one poly(aryletherketoneketone). It was found that the large length/diameter ratio of the polymer repeat unit for cardo polyaryletherketoneketone (PEKK-C) and strong intermolecular interaction in hydrogen-bonded polyarylethersulfone (PES-H) and hydrogen-bonded polyaryletherketone (PEK-H) resulted in a considerable increase in gas permselectivity. Alkyl-substituted polyaryletherketone (PEK-A), bearing a pendant bulky propyl group on the cardo ring, simultaneously exhibited 62.5% higher H-2 permeability and 59.8% higher H-2/N-2 permselectivity than unmodified poly(aryletherketone) (PEK-C). The causes of the trend were interpreted in terms of chain packing density, segmental motion ability, steric factor, and intermolecular interaction of polymers, together with gas kinetic diameter and critical temperature data.

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A series of cardo polyaryletherketones and polyaryletersulfones containing alkyl substituents of a different kind, number and volume were synthesized from bis(4-nitrophenyl)ketone or bis(4-fluorophenyl)sulfone with various alkyl substituted phenolphthaleins by polycondensation using K2CO3 as catalyst. Their chemical and aggregation structures were confirmed by FT-IR, H-1-NMR and WAXD. The resulting polymers were soluble in a variety of common polar solvents and, transparent, colorless, and tough films could be easily cast from 1,1,2-trichluoroethane solution. Their tensile strength, elongation at break and tensile modulis were in the range of 70.5 similar to 97.1MPa, 4.49%similar to7.81%, and 1.69 similar to2.27GPa, respectively. The prepared polymers had reasonably high glass transition temperatures at 207 to 269 degreesC, and showed fairly good thermal stability with 5% thermal decomposition loss above 410 degreesC.

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Gas transport of hydrogen, oxygen, nitrogen, carbon dioxide, and methane in four cardo poly(aryl ether ketone)s containing different alkyl substituents on the phenyl ring has been examined from 30 to 100 degrees C. The permeability, diffusivity, solubility, and their temperature dependency were studied by correlations with gas shape, size, and critical temperature as well as polymeric structural factors including glass transition, secondary transition, cohesive energy density, and free volume. The bulky, stiff cardo and alkyl groups in tetramethyl-substituted TMPEK-C resulted in increased H-2 permeability (by 55%) and H-2/N-2 permselectivity (by 106%) relative to bisphenol A polysulfone (PSF). Moreover, the weak dependence of gas transport on temperature in TMPEK-C made it maintain high permselectivities (alpha(H2/N2) in 68.3 and alpha(O2/N2) in 5.71) up to 100 degrees C, exhibiting potential for high-temperature gas separation applications.

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Some novel macrocyclic (arylene ether sulfone) containing cardo groups and (arylene ether ketone sulfone) oligomers have been synthesized in high yields by a nucleophilic aromatic substitution reaction of 4,4'-difluorophenylsulfone with bisphenols in the presence of anhydrous potassium carbonate under a pseudo-high-dilution condition. Detailed structural characterization of these oligomers by matrix-assisted laser desorption/ionization-time of flight-mass spectrometry (MALDI-TOF-MS), fast atom bombardment mass spectrometry (f.a.b.-m.s.), nuclear magnetic resonance spectrometry (n.m.r.) and single-crystal X-ray structure analysis confirms their cyclic nature, and the composition of the oligomeric mixtures is provided by g.p.c. analysis. Ring polymerization of cyclic oligomers 3a to a high molecular weight polymer with M-w of 59.1 k was achieved by heating at 290 degrees C for 40 min in the presence of a nucleophilic initiator. (C) 1998 Elsevier Science Ltd. All rights reserved.

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The gas permeation properties of a series of cardo polyaryletherketone materials are reported, In this series, the hydrogen atoms of benzene rings on the backbone are systematically replaced with different alkyl substituents. The effects of temperature and structure variation on gas permeability and selectivity are discussed in detail. The experimental results revealed that the polyetherketone obtained by the introduction of dimethyl and diisopropyl substituents to phenolphthalein unit is 3 similar to 6 times more permeable than the unmodified one for the gases studied.

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研究了带有不同烷基取代基的Cardo聚芳醚酮均质膜对H2、O2、N2、CO2和CH4气体的透气性能,讨论了气体透过对温度的依赖性。与未改性酚酞聚芳醚酮相比,在主链苯环上引入异丙基侧基会使气体透过系数提高3~6倍;每个结构单元苯环被4个甲基取代后,气体透过系数和选择分离系数同时得到较大改善,其中H2的透过系数为22barrer,H2/N2分离系数为114。

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作者用溶液缩聚方法合成了一系列含Cardo侧基的聚芳醚酮(PEK—C)共聚物,研究了氢气、氮气和氧气的透过速率随共聚组成的变化规律,研究结果表明,此系列共聚物的气体透过速率随共聚组成呈S形关系变化,并且与共聚物的自由体积参数之间有较好的线性相关性

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几种Cardo聚芳醚砜膜的气体透过行为王忠刚,陈天禄,徐纪平(中国科学院长春应用化学研究所长春130022)关键词Cardo聚芳醚砜,膜,气体分离近年来的研究结果表明:同时增加聚合物的自由体积和限制分子链的链段活动性可以同时改善聚合物的气体透过系数和...

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几种Cardo聚芳醚砜的合成与表征王忠刚,陈天禄,徐纪平(中国科学院长春应用化学研究所长春130022)关键词Cardo聚芳醚砜,缩聚反应,合成酚酞型聚芳醚砜(PES-C)是综合性能优异的热塑性工程塑料[1],可通过溴化、磺化等改性[2~6].本文用...

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含不同取代基的Cardo聚芳醚酮──合成与表征王忠刚,陈天禄,徐纪平(中国科学院长春应用化学研究所长春130022)关键词Cardo聚芳醚酮,合成与表征,自由体积,玻璃化转变温度酚酞型Cardo聚芳醚酮(PEK-C)是长春应化所合成的一种新型高一T,...

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The effects of irradiation on some members of the family of aromatic polymers with a cardo group, such as polyetherketone with a cardo group (PEK-C) and polyethersulfone with a cardo group (PES-C), were studied. It was found that PEK-C and PES-C can be crosslinked by irradiation under vacuum. Moreover, it was also found that the intensity of the shake-up peak of x-ray photoelectron spectroscopy (XPS) for PEK-C and PES-C varies with irradiation dose. Gelation doses (Rg) of PEK-C and PES-C were estimated from the XPS shake-up peak.

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基于在“一步法”聚合反应过程中发现的酚酞对反应有特殊的“自催化”作用,本文合成了几种具有与酚酞类似结构的Cardo双酚,并通过对其聚合反应规律的研究,进一步探讨“自催化”作用的本质。实验结果表明,这类Cardo双酚也较普通结构双酚更易于进行异相成盐反应,表现为其聚合反应速度的明显加快。

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酚酞型聚醚砜(C-PES)是一种综合性能优异的工程塑料和功能材料,具有良好的成膜性、机械性能、热稳定性、化学稳定性和可加工性等。作为一种高性能的膜材料,酚酞型聚醚砜已被广泛的用于气体分离和水处理等领域。酚酞型聚醚砜侧链上含有可修饰的酯基,可通过各种方法,引入功能基团,对其进行化学改性,从而改善C-PES的各种性能,并扩展其应用领域。本论文设计制备了含有烷基、芳基、胺基以及磺酸基等功能基团的新型酚酞型聚醚砜材料,并对其性质进行了深入的研究: 1.通过各种基团修饰的二酚单体和二氯二苯砜的缩聚,合成了新型的含有不同酞侧基的Cardo型聚醚砜高分子材料,并对其性能进行了详细的研究。结果表明,所有聚合物都表现出极好的溶解性、耐热稳定性、成膜性、力学性能和气体分离性能;通过在酞侧基上引入了大体积的对叔丁基苯基,大大改善了材料的透气性和氧氮分离选择性;通过引入仲胺基,增大了聚合物链间作用力,从而提高了气体的分离选择性。此外,我们还对不同基团的引入对聚合物各种性能的影响作了详细的探讨,着重研究了聚合物的结构-性能关系。 2.利用含有胺基的双酚单体PPH-NH2、PPH和二氯二苯砜的共聚反应,成功合成了含有胺基的Cardo型聚醚砜高分子材料(PES-NH2),并对材料的各种性质进行了表征。结果表明,由于胺基的引入,酚酞型聚醚砜的亲水性得到了大幅度的提高。 3.利用含胺基的Cardo双酚和磺化二氯二苯砜在碳酸钾作用下的缩聚反应,成功合成了含胺基的磺化Cardo型聚醚砜 (SPES-NH2),并用于制备反渗透复合膜。通过优化制膜条件,我们利用界面聚合的方法成功制备了高水通量的TMC/ MPDA/SPES-NH2反渗透复合膜,并对复合膜的性能和结构进行了研究,重点讨论了膜的性能和结构、形貌之间的关系。结果表明,通过在复合膜活性层中引入强亲水性的磺酸基和全刚性主链的Cardo型聚醚砜,复合膜在保持较高盐截留率(97.3%)情况下,水通量得到了大幅度的提高,达到了51.2 L/m2.h。 4.合成了新型的全刚性芳香主链的两性聚电解质SPES-NH3+,并对其溶液性质和自组装行为进行了详细的研究。结果表明,在一定的溶液pH值下,两性聚电解质SPES-NH3+表现出聚阴离子的性质。另外,通过引入[BMIM]+离子屏蔽磺酸根负离子,我们在没有加入其它聚电解质的情况下,成功地制备了[BMIM]SPES-NH3+多层膜,并对多层膜表面性质进行了研究。结果表明,多层膜的厚度可由层数来控制,并且膜表面较平滑,其RMS值为6 nm。这种新的组装方式为构筑刚性主链的两性聚电解质多层膜提供了新的方法。