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液晶研究(Ⅰ)──4'-酰基-4-羟基-1,1'-联苯酯类液晶的合成与性质 总被引:1,自引:0,他引:1
以4'-羟基联苯为原料合成了8种新型4'-酰基-4-羟基联苯酯类化合物.除化合物5_h外,均为新的近晶相液晶化合物.它们具有较宽的相变温度范围和较高的热稳定性.用偏光显微镜和差热分析仪研究了它们的相行为,讨论了分子结构对液晶相行为的影响. 相似文献
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液晶基元直接竖挂于主链上的液晶共聚物的研究 总被引:2,自引:0,他引:2
合成了含液晶基元的单体,4+4'-(对甲氧基-苯甲酰氧基)-苯甲酸氧基]-苯基-甲基丙烯酸酯,以及由此单体与苯乙烯,通过自由基共聚合反应合成了一系列含液晶性和非液晶性两种序列结构的共聚物.采用DSC、偏光显微镜和X-衍射方法研究了共聚物的液晶行为,发现单体和所有的共聚物(除CP—9外)均有很好的热致液晶性及较宽的液晶态温度范围;随苯乙烯单体单元摩尔百分含量的增加,共聚物的分子量、相转变温度和热失重温度基本上呈下降趋势.通讯联系人0.sg/dl的溶液,于40oC用乌氏粘度计测定.l·2单体合成合成路线如下:化合物I、11、Ill和IV的制备按文献l’]的方法进行.化合物1、11、Ill和IV经元素分析、‘H—NMR和MS等表征,结果与其化学结构~致.1.3聚合物的合成聚合反应和共聚物结构式表示如下:按单体(IV)与苯乙烯不同摩尔比,以DMF为溶剂,AIBN为引发剂(相当于单体摩尔数的0.50).通过封管聚合,在60oC水浴中反应36h,升温至70oC反应12h,抽滤,用DMF和甲醇洗,真空干燥.2结果与讨论2.l含液晶基元的单体(I)化合物1、11、Ill和IV经测试分析结果与其化学结构一致.由表1可见,单体? 相似文献
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研究了在氯化氢-乙醇溶液或乙醇溶液中,2,4-二羟基苯乙酮与甲醛和芳胺的Mannich反应,分别得到了5个2,4-二羟基-3-芳氨基甲基苯乙酮和5个8-乙酰基-3-芳基-3,4-二氢-5-羟基-2H-1,3-苯并嗪新化合物。用元素分析、IR、1HNMR、MS、UV确定了它们的结构,并成功地实现了2,4-二羟基-3-芳氨基甲基苯乙酮和8-乙酰基-3-芳基-3,4.二氢-5-羟基-2H-1,3-苯并嗪二类化合物的转化。 相似文献
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采用低温溶液聚合方法,以N-(2,5-二羟基苯)亚甲基-4-取代苯胺和不同结构的二酰氯为单体,合成了两类新的高分子.聚合物的液晶行为用DSC、偏光显微镜和X射线衍射进行了表征,发现其中一类为向列型热致液晶高分子,另一类则无液晶性.随单体结构的改变,聚合物的特性粘数、熔点(Tm)和液晶态的清亮点(Ti)均呈现规律性变化。 相似文献
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通过实验证实杂多酸对甲苯磺化合成4,4’-二甲二苯砜反应具有较好的催化活性,利用紫外光谱研究了杂多酸与对甲苯磺酸的作用。 相似文献
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Mehdi Barikani Shahram MehdipourAtaei 《Journal of polymer science. Part A, Polymer chemistry》2000,38(9):1487-1492
A new aromatic sulfone ether diamine was synthesized by nucleophilic aromatic substitution reaction of 5‐amino‐1‐naphthol with bis(4‐chlorophenyl) sulfone in the presence of potassium carbonate in a polar aprotic solvent. Polycondensation reactions of the obtained diamine with pyromellitic dianhydride (PMDA), benzophenonetetracarboxylic dianhydride (BTDA), and hexafluoroisopropylidene diphthalic anhydride (6FDA) resulted in preparation of thermally stable poly(sulfone ether imide)s. Poly(sulfone ether amide)s also were prepared by reaction of the diamine with terephthaloyl chloride (TPC) and isophthaloyl chloride (IPC). The prepared monomer and polymers were characterized by conventional methods. Physical and mechanical properties of polymers, including thermal stability, thermal behavior, solution viscosity, solubility behavior, and modulus, also were studied. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 1487–1492, 2000 相似文献
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In many reactions involving selenosulfonate or thiosulfonate,the sutfone group often leaves in form of benzenesutfinic acid or sodium benzenesulfinate.A one-pot two-step reaction of selenosulfonate with isocyanides and allyl alcohol under aqueous conditions to afford selenocarbamates and allyl sulfone compounds is reported.The sulfinic acid as the first-step side product is converted to the allyl sulfone compound by water promoted reaction with allyl alcohol.Water acts as both an oxygen source of selenocarbamates and as a promoter to drive the second step reactio n.The reactions have the advantages of mild conditions,green,environment-friendly,and high atomic economy. 相似文献
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《Tetrahedron letters》2019,60(24):1566-1569
The stability and the stereoselectivity of newly prepared n-pentyl 1-methyl-1H-tetrazol-5-yl (MT) sulfone 1a in the Julia-Kocienski reactions were compared with those of the PT sulfone 1b and the TBT sulfone 1c. The improved stability of the anion derived from the n-pentyl MT sulfone 1a enhanced the efficiency of the olefination reactions and gave higher yields of the product alkenes 3 compared with the PT sulfone 1b. Especially high E-selectivity and high yields were obtained from the reaction with aromatic aldehydes and α,β-unsaturated aldehydes. The selectivity of 1a was not so sensitive to the change of base counter ion compared with the PT sulfone 1b. The reaction of the MT sulfones having either ethyl or a longer alkyl chain also gave E-alkenes selectively in high yields. 相似文献
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Functionalized poly(phthalazinone ether sulfone ketone) was synthesized by successive chloromethylation and azidation, followed by curing reaction with the propargyl end-groups of various molecular weight crosslinking agents in the presence of Cu(Ⅰ) catalyst via the azide-alkyne click reaction. The influences of the chain length of crosslinking agents on the poly(phthalazinone ether sulfone ketone) system were studied. FTIR and DSC tests demonstrated certain crosslinking by azide-alkyne reaction with the formation of triazole ring. DSC results showed that curing temperature shifted to lower temperatures considerably in the presence of Cu(Ⅰ) catalyst. TGA showed cured polymers were of much higher thermal stability, including higher thermal decomposition temperatures and higher char-yielding properties. After being cured, the polymers became insoluble in organic solvents and the gel fraction of the cured polymers exceeded 71%. Wide-angle X-ray diffraction results indicated there was a short distance order in the poly(ether sulfone)(PES) main chain except for the azido methyl poly(phthalazinone ether sulfone ketone) and 4,4'-bis(2-propynyloxy) biphenyl( AMPPESK-BP) system. 相似文献
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Poly(N-arylenebenzimidazole pyridine sulfone)(PNABIPS) has been prepared via the aromatic nucleophilic displacement reaction of 2,6-bis(2-benzimidazoly)pyridine(BBP) with bis(4-fluorophenyl) sulfone.BBP was synthesized by reaction of 2,6- pyridinedicarboxylic acid with 1,2-phenylenediamine in polyphosphoric acid.The chemical structure of BBP was confirmed by FTIR, HRMS,1H NMR and 13C NMR.The characterization of the polymer was performed with FT-IR,1H NMR,elemental analysis, GPC,XRD,DSC,TGA and solubility tests.The polymer was obtained in quantitative yield with Mn value 12,600 and Mw value 28,300,respectively.DSC and TGA measurements show that the glass transition temperature(Tg) is 312℃ and 5%weight loss temperature is 434℃ in nitrogen and 545℃ in air,respectively.In addition,the novel polymer exhibits good solubility,which can be dissolved in common organic solvent at room temperature. 相似文献
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MeiHuaXIE LuLingWU XianHUANG 《中国化学快报》2003,14(9):887-888
Phenylseleno and sulfonyl substituted allyl alcohols were synthesized stereoselectively by the three-componem reaction of acetylenic sulfone, phenylselenomagnesium bromide and ketones in one-pot. 相似文献
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Fan Xiu MENG Chun Qing ZHANG Lian LIU Yuan Yuan ZHANG 《中国化学快报》2006,17(4):447-448
N,N'-Bis(3-hydroxyphenyl)-1,8,4,5-naphthalenetetracarboxylic bisimide was prepared from the reaction of 1,8,4,5-naphthalenetetrcarboxylic acid dianhydride and 2-aminophenol in N, N-dimethylformamide. Polymerization of this bisimide with 4,4'-difluorodiphenylsulfone and disodium 3,3'-disulfonate4,4'-difluorodiphenylsulfone gave ion-exchange sulfonated poly(ether sulfone). The structure of the title compound was characterized with 1H-NMR and its polymer was characterized with FT-IR. 相似文献