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耐高温聚酰亚胺树脂研究 总被引:1,自引:0,他引:1
综述了耐高温聚酰亚胺树脂及其碳纤维增强复合材料、耐高温聚酰亚胺超级工程塑料和高性能功能性聚酰亚胺薄膜等的研究进展。耐高温聚酰亚胺树脂包括第一代耐316℃系列、第二代耐371℃系列、第三代耐426℃3个系列的产品;耐高温聚酰亚胺超级工程塑料包括反应性热模压成型和高温注塑成型的材料;高性能聚酰亚胺薄膜包括透明性聚酰亚胺薄膜和抗原子氧PI薄膜树脂。本文介绍了它们的结构,工艺以及性能,并对其在航天、航空空间技术及微电子等其它领域中的应用情况做了简单的介绍。 相似文献
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以2-苯基-4,4'-二氨基二苯醚(p-ODA)、异构二苯醚二酐(ODPA)和苯乙炔基苯酐(PEPA)为原料,通过两步法合成了聚合度分别为1,2和3的酰亚胺树脂低聚物,并通过模压成型法制备了单向碳纤维增强的聚酰亚胺复合材料.表征了酰亚胺树脂低聚物的溶解性、熔体黏度及其固化物聚酰亚胺树脂的热性能,结果表明,聚酰亚胺树脂具有良好的溶解性,在N,N-二甲基乙酰胺(DMAc)、四氢呋喃(THF)及1,4-二氧六环等溶剂中的溶解度大于30%;所有酰亚胺树脂低聚物的最低熔体黏度均在10 Pa·s以下,具有良好的成型工艺性;聚酰亚胺树脂具有良好的热性能,玻璃化转变温度(Tg)最高可达300℃,5%热失重温度(T5%)最高可达545℃,碳纤维增强聚酰亚胺复合材料PIC-4,4'-ODPA-2具有最佳的高低温力学性能. 相似文献
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可溶性聚酰亚胺共聚物的制备及其性能 总被引:2,自引:0,他引:2
通过共缩聚及改变单体加料顺序和方法,得到了两系列共聚型聚酰亚胺,并应用Fr-IR、UV、X射线衍射、TGA、机械性能测试等方法,对所得聚酰亚胺树脂的性能进行了表征。结果表明,所得共聚型聚酰亚胺树脂成膜性能良好,能够得到坚韧且具有弹性的薄膜材料,其在400~450nm区域的透过性能良好,在有机溶剂中的溶解性能显著增强,并保持了聚酰亚胺特有的良好机械性能及耐热性能。 相似文献
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聚醚酰亚胺/酚酞型聚醚醚酮共混体系相容性的稀溶液粘度法研究 总被引:1,自引:0,他引:1
<正> 近年来,有关高性能树脂聚酰亚胺共混物的研究日益引起人们的关注。已经发现许多种分子结构不同的聚酰亚胺之间,聚酰亚胺与聚苯并咪唑,或聚醚醚酮能形成完全相容的共混体系,从而扩大了高性能树脂聚酰亚胺的应用范围。 酚酞型聚醚醚酮(PEK-C)是由我所研究开发出的一种新型的聚醚醚酮类高性能树脂,它具有良好的可溶性,优异的机械强度和加工流动性,已广泛应用于结构材料及复合材料的制备。为进一步扩大该树脂的应用范围,本实验室在PEK-C共混物的研究做了大量的工作。本工作研究了聚醚酰亚胺(PEI)/PEK-C共混体系的相容性。PEI和PEK-C的分子结构如下: 相似文献
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近年来,半互穿聚合物网络(SIPN)概念被用来研制能结合热塑性聚合物的加工性和热固性聚合物的高温性能的大分子体系,用于复合材料耐高温树脂基体。例如:乙炔端基酰亚胺低聚物与热塑性聚酰亚胺基SIPN,线性聚酰亚胺与热固性双马来酰亚胺基SIPN以及热塑性树脂与双腈基SIPN已有报道。研究结果表明共混物起到协同作用,易于加工并具有优异的性能。乙炔端基砜(ATS)树脂具有与聚砜树脂相类似的结构,被认为在将来代替环氧用于高性能粘合剂和复合材料树脂基体的候选者之一。其另 相似文献
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聚酰亚胺是一类重要的高性能高分子材料,具有优异的热性能、机械性能、电学性能和尺寸稳定性等,同时具有良好的结构可设计性,已逐渐成为有机光电领域的研究热点.然而,传统聚酰亚胺材料一般不发光,文献中有关发光聚酰亚胺的研究并不多.同时,所报道的荧光量子产率普遍较低,极大地限制了其作为发光功能层在有机光电器件领域的应用.为了更好地了解聚酰亚胺发光的规律,拓展高性能聚酰亚胺材料在有机发光器件中的应用领域,本文介绍了聚酰亚胺光致发光的机理,综述了国内外有关光致发光聚酰亚胺的研究进展,总结了提高聚酰亚胺荧光量子产率的方法,并对未来高性能高效发光聚酰亚胺材料的研究方向做了展望. 相似文献
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Uroš Grošelj Mojca Žorž Amalija Golobič Branko Stanovnik Jurij Svete 《Tetrahedron》2013,69(52):11092-11108
A new and simple synthesis of novel N-protected methyl 5-substituted-4-hydroxypyrrole-3-carboxylates, which exist in equilibrium with their 4-oxo tautomers, has been developed in two steps starting from N-protected α-amino acids. The key intermediates are enaminones, which can also be isolated, characterized, and used for the construction of other functionalized heterocycles, before they spontaneously decompose to pyrrole products. 4-Hydroxypyrroles are prone to partial aerial oxidation but can be efficiently alkylated or reduced to stable polysubstituted pyrrolidine derivatives. 相似文献
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The chemoselectivity in the intramolecular CH insertion of various diazosulfonamides has been experimentally studied. The results reveal that the aliphatic 1,4-, 1,5-, or 1,6-C(sp3)?H insertions of diazosulfonamides are not accessible, while the aromatic 1,5-C(sp2)?H insertion can be realized specifically by adjusting the diazo-adjacent group. In addition, the general chemoselectivities in the intramolecular CH insertions of diazosulfonyl compounds are summarized. Generally, diazosulfones undergo both aromatic 1,5-C(sp2)?H and aliphatic 1,5- and 1,6-C(sp3)?H insertions, while diazosulfonates undergo aliphatic 1,5- and 1,6-C(sp3)?H insertions. However, diazosulfonamides only undergo aromatic 1,5-C(sp2)?H insertion. 相似文献
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N-Heterocyclic carbene-palladacyclic complexes 3 were successfully achieved in a one-pot procedure under mild conditions. The structure of 3a was unambiguously confirmed by X-ray single crystal diffraction and it was an active catalyst in the Buchwald-Hartwig amination and α-arylation of ketones even at very low catalyst loadings (0.01?mol%). 相似文献
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Shashikant U. Dighe Surya K. Samanta Shivalinga Kolle Sanjay Batra 《Tetrahedron》2017,73(17):2455-2467
An efficient iodine-mediated oxidative Pictet-Spengler reaction in dimethyl sulphoxide (DMSO) using terminal alkynes as the 2-oxoaldehyde surrogate for the synthesis of aryl (9H-pyrido[3,4-b]indol-1-yl)methanones is described. The scope of the protocol includes the total synthesis of Fascaplysin, Eudistomins Y1 and Y2. The methodology is extended for preparing pyrrolo[1,2-a]-quinoxaline and indolo[1,5-a]quinoxaline derivatives. The utility of 1-aroyl-β-carbolines was demonstrated by performing palladium-catalyzed β-carboline directed ortho-C(sp2)-H functionalization of the phenyl ring with thiomethyl (SMe) group using DMSO as source and for accessing 4-aryl-canthin-6-ones. 相似文献
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In this Letter, we described a facile method for constructing fused bicyclic 1-arylpyrazol-5-one ring system. We employed various methylene-containing carboxylic acids as the substrates and proved that the pyrazolone ring closure requires activated methylene group in intermediate II. Accordingly, a series of structurally diversified, fused bicyclic 1-arylpyrazol-5-ones was prepared in moderate to high yields using the requisite substrates. 相似文献
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Synthesis of substituted pyrrolo[1,2-a]pyrazines and pyrazino[1,2-a]indoles from the Morita-Baylis-Hillman derivatives of acrylates via saponification followed by Curtius reaction is described. 相似文献
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用正丁胺作为碳源,采用射频辉光放电制备碳膜,选用激光染料R6G和聚乙二醇混合液作为蒸气源,采用单源热蒸发,在蒸发室与染料同时沉积得到混合膜,用拉曼光谱和红外光谱分析了碳膜的结构和键合方式,分析表明:碳膜中存在胺基团和氢原子.混合膜的荧光谱测量结果表明,认为正丁胺对染料荧光谱的影响是因为胺基和氢原子的存在. 相似文献
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Jona Mirnik Eva Pušavec Kirar Sebastijan Ričko Uroš Grošelj Amalija Golobič Franc Požgan Bogdan Štefane Jurij Svete 《Tetrahedron》2017,73(24):3329-3337
A series of 20 CuAIAC reactions between eight 4-acylamino substituted pyrazolidine-3-one-1-azomethine imines and four terminal ynones were performed using Cu0 as catalyst. The corresponding fluorescent cycloadducts were obtained in very high yields upon simple workup. Thus, Cu-metal turned out to be a better catalyst than CuI in terms of yield and ease of isolation. Availability of azomethine imines, mild reaction conditions, and simple workup enable a “click” access to libraries of densely substituted 2,3-dihydro-1H,5H-pyrazolo[1,2-a]pyrazol-1-ones. Reactivity of differently substituted dipoles was evaluated experimentally and by quantum chemical methods (DFT). 相似文献
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George E. Magoulas Thomas Garnelis Constantinos M. Athanassopoulos Dionissios Papaioannou George Mattheolabakis Konstantinos Avgoustakis Dimitra Hadjipavlou-Litina 《Tetrahedron》2012,68(35):7041-7049
(E)-4-(Fullerenopyrrolidin-1-yl)-3-methylbut-2-enoic acid and its corresponding succinimidyl ester, readily obtained through Prato-type modification of C60, were used for the selective N-acylation of polyamines. The thus obtained conjugates were evaluated for their antioxidative and anti-inflammatory activity and their cytotoxicity was determined. Members of this family of compounds showed interesting anti-lipid peroxidation, anti-lipoxygenase and anti-inflammatory activity and comparable cytocompatibility to spermidine. 相似文献