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本文以邻溴苯甲醛为原料,经亲电加成反应、氧化反应以及分子内Friedel-Crafts烷基化反应合成了7-溴-2,3-二氢-1-茚酮。研究发现,分子内Friedel-Crafts烷基化是影响总收率的关键步骤,探讨了反应溶剂、反应温度、反应时间等条件对反应的影响。同时,对氧化反应步骤中氧化剂及反应溶剂进行了筛选,结果发现,在以丙酮为溶剂琼斯试剂为氧化剂的条件下,产物收率最高。所有产物经NMR和MS进行确证。 相似文献
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采用过渡金属配合物催化乙烯齐聚是制备α-烯烃的一条重要工艺路线,部分催化体系已进入了中试和工业化生产阶段,但近年来的研究工作表明,一些过渡金属催化剂在甲苯溶剂中的齐聚产物可直接与甲苯发生Friedel-Crafts烷基化反应,这将为烷基苯的生产开辟一条新的途径。综述了近年来乙烯齐聚过程中发生Friedel-Crafts烷基化反应的研究进展,详细阐述了催化剂的结构、催化体系、工艺条件等对烷基化反应及烷基化产物分布的影响。同时,给出了乙烯齐聚中Friedel-Crafts烷基化反应的反应过程,对设计可催化乙烯齐聚制备混合烷基苯的催化剂具有重要的意义。 相似文献
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对硝基苯酚经铁粉/氯化铵还原得到对氨基苯酚,后者经氯乙酰化和N-烷基化反应合成N-(4-羟基苯基)-2-(1H-咪唑-1-基)乙酰胺。并考察了酰化以及N-烷基化等关键步骤的反应条件,较佳的反应条件为酰化反应以乙酸钠作为缚酸剂,反应温度20℃;N-烷基化以碳酸钾作为缚酸剂,碘化钠为催化剂。总收率31.4%,产物经过1H NMR和MS表征。 相似文献
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环己基苯经过氧化反应可生产苯酚和环己酮,还可以用作锂离子电池电解液的添加剂,也可用作柴油的十六烷值调和组分,是一种高附加值、有市场潜力的精细化学品。本文介绍了国内外通过苯与环己烯烷基化合成环己基苯及所用催化剂的研究进展,总结了苯加氢烷基化反应机理和反应路径的研究成果,包括加氢烷基化活性的来源、中间产物和碳正离子中间体的推断以及各反应产物的形成。通过对加氢烷基化机理的认识,回顾了加氢烷基化催化剂的设计思路和发展历程。最后指出可开发用于苯与环己烯烷基化的B酸型、B-L酸型以及固载化离子液体等新型催化剂。提出可借助最新的碳正离子研究手段对加氢烷基化机理进行补充完善,并认为可利用多级孔沸石作为加氢烷基化催化剂的酸性载体。 相似文献
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以交联型特辛基酚醛树脂为原料进行改性,得到了一种交联型酚羟基间位溴化特辛基酚醛树脂,采用红外光谱(FTIR)、核磁碳谱(NMR)对树脂的结构进行了表征,结果表明成功地在酚羟基的间位上取代上了溴。采用莫尔法滴定反应测定剩余溴含量,计算得到苯环上的溴化率为84.7%。采用凝胶渗透色谱(GPC)对改性前后的酚醛树脂进行表征,结果表明经过溴化改性的酚醛树脂的数均分子量、重均分子量有所降低,分子量分布变窄。根据交联型特辛基酚醛树脂的交联机理,分别对交联型特辛基酚醛树脂、交联型链端溴化特辛基酚醛树脂树脂和交联型酚羟基间位溴化特辛基酚醛树脂交联橡胶的硫化历程和物理力学性能进行测试,结果表明改性后的酚羟基间位溴化特辛基酚醛树脂交联橡胶的硫化程度、硫化速度、力学性能都有明显提升。 相似文献
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《热固性树脂》2017,(5)
在碱性条件下以对-特辛基苯酚与对-壬基苯酚或十二烷基苯酚的混合物与甲醛缩合反应得到混合烷基苯酚酚醛树脂缩合液,并将缩合液加入到熔融的松香中反应得到松香改性酚醛树脂。在苯磺酸类催化剂作用下,向松香改性酚醛树脂中加入多元醇进行酯化反应,再加入二元羧酸继续反应得到高档热固油墨用松香改性长链烷基酚醛树脂。对产物的结构进行了红外、热重分析表征。产物粘度18 000 m Pa·s左右,软化点151℃,庚烷值23.8 m L/2 g,酸值(KOH)22.4 mg/g,色泽7号,分子质量分散度分布11.64,适用于高档热固油墨,在高速轮转胶印过程中能明显提高轮转印刷效率,同时不存在乳化和飞墨现象。 相似文献
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采用多聚甲醛代替37%的甲醛溶液,在20%NaOH水溶液催化下与苯酚逐步加成聚合,合成了可发性甲阶酚醛树脂。研究了多聚甲醛与苯酚物质的量比(F/P)对合成树脂固含量、粘度、游离苯酚、游离甲醛、凝胶时间、分子结构、分子质量、树脂热性能及泡沫性能的影响。结果表明,F/P值为1.8时,可得到性能优良成本较低的可发性甲阶酚醛树脂,树脂粘度1.4 Pa.s,游离甲醛质量分数1.17%,游离苯酚质量分数6.72%,羟甲基指数1.41,树脂分子质量在240左右,耐热性较好。 相似文献
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Seung‐Hwan Lee 《应用聚合物科学杂志》2003,87(8):1365-1370
To prepare phenolic resol resin, corn bran (CB) was liquefied in the presence of phenol and the liquefied CB was condensed with formaldehyde under alkaline condition. From NMR spectra of phenolated CB and phenolated CB–based resol resin, it was found that phenol was reacted with depolymerized CB components and the phenolated CB was methylolated by condensation with formaldehyde. Molecular weight distribution was divided into a high molecular weight zone, attributed mainly to phenolated CB, and a low molecular weight zone, which was attributed to the condensation reactants of formaldehyde and the unreacted phenol of liquefied CB. When reaction conditions became severe, a high molecular weight zone was increased. Formaldehyde/unreacted phenol of liquefied CB molar ratio most affected the change of a low molecular weight zone. To reduce the viscosity of the phenolated CB–based resol resin, a milder condensation condition was required compared with that for preparing the conventional resol resin. Properties of the resol resin were comparable to those of conventional resol resin for plywood manufacture. © 2002 Wiley Periodicals, Inc. J Appl Polym Sci 87: 1365–1370, 2003 相似文献
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Hydrocarbon-soluble oligomers were prepared by the acid-catalyzed condensation of alkylanilines with formaldehyde. Highest molecular weight oligomers (MW ~ 6000) were obtained from alkylanilines prepared by the Friedel-Crafts alkylation of aniline with α-olefins. By NMR, it was shown that the oligomers contain structures corresponding to methylene-linked aromatic rings and methylene linked to both an aromatic ring and a nitrogen atom. The oligomers exhibit very good initial inhibition of metal corrosion in aqueous environment; and the inhibition is more persistent than that observed with monomeric analogs. 相似文献
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A boron‐containing cyclohexanone formaldehyde resin (BCFR) was synthesized from cyclohexanone, formaldehyde, and boric acid. The effects of the boric acid concentration, solubility, molecular weight, and thermal properties on the product were investigated. Characterization of the BCFRs was done by NMR spectroscopy, gel permeation chromatography, and Fourier transform infrared–attenuated total reflectance spectroscopy. The thermal properties of the samples were determined with differential scanning calorimetry and thermogravimetric analysis. The study results demonstrate that the resin had higher heat‐resistance properties than the commonly modified cyclohexanone formaldehyde resin. The obtained samples were also characterized morphologically by scanning electron microscopy. © 2013 Wiley Periodicals, Inc. J. Appl. Polym. Sci., 2013 相似文献
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Phenol resin as coal model was extracted with quinoline at 420°C for 2 h. The insoluble part was only 2.7%. The soluble part was separated into 7 fractions and their ultimate analysis, molecular weight and NMR spectra were measured. Model structures were proposed for these fractions. The increase of nitrogen content and the identification of the presence of 2,2′-biquinoline in the product are explained by a solvolysis reaction of quinoline with the thermally decomposed radicals of phenol resin. 相似文献
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以六氯环三磷腈(HCCP)、苯酚、氢化钠为原料,碳酸钾为催化剂,丙酮为溶剂,在氮气保护下合成了六苯氧基环三磷腈(HPCP)。采用红外光谱、核磁氢谱、碳谱、磷谱、差示扫描量热分析、热重分析技术对产物进行了表征。将HPCP作为阻燃剂添加到丙烯酸树脂中,测试了HPCP不同添加量的丙烯酸树脂的阻燃性和热稳定性。结果表明,当HPCP的添加量为20 wt %时,丙烯酸树脂的垂直燃烧可达UL-94 V-0级,极限氧指数从17.5 %增加到32.2 %,空气中700 ℃时残留质量提高至18.95 %,平均热释放速率(Mean HRR)和总热释放量(THR)分别降低至43 kW/m2和37 MJ/m2。 相似文献
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以纳米TiO2的丙二醇甲醚醋酸酯(PMA)分散液为添加剂改性激光快速成型用光固化树脂SPR4000,通过对树脂及固化物的酸值、分子质量、IR、DSC、热重分析、流变性及力学和热性能测试等研究了改性后光固化树脂的性能,并用扫描电镜对纳米TiO2在树脂中的分散情况进行了观察。结果表明添加的二氧化钛质量分数为0.75%时,体系力学性能最好,拉伸强度提高15.25%,冲击强度提高41.35%,弯曲强度提高41.75%,耐热性也有所提高。纳米二氧化钛PMA分散液的加入解决了纳米二氧化钛在树脂中的分散稳定性问题,保证了树脂体系的固化速度及交联密度,满足了制作工艺,提高了光固化树脂SPR4000的力学性能。 相似文献