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1.
一种新型的糖基型紫外线吸收剂的合成和表征   总被引:1,自引:0,他引:1  
<正>紫外线是太阳光谱中波长200~400nm部分的电磁波,约占太阳辐射的6%,按波长不同,又可分为UVC(短波紫外线,200~280nm)、UVB(中波红斑效应紫外线,280~320nm)、UVA(长波黑斑效应紫外线,320~400nm)3个区段,其中UVC几乎全部被大气层阻滞,对人体无法造成伤害。  相似文献   

2.
丁阳  杨義  任学宏  李蓉  黄丹 《化学通报》2016,79(12):1161-1165
以三聚氯氰(TCT)、2,4-二羟基二苯甲酮(UV-0)、双丙酮葡萄糖为原料,经三步反应合成一种具有反应性基团的水溶性紫外吸收剂3-(2-(2-羟基苯基苯甲酮-4-氧基)-4-氯-1,3,5-三嗪-6-氧基)-1,2-异丙叉-α-D-葡萄糖(UV-DTM),产物的结构经IR、NMR和MS表征。探讨了每一步反应的条件对反应产率的影响。合成3-(4,6-二氯-1,3,5-三嗪-2-氧基)-1,2,5,6-双异丙叉-α-D-葡萄糖(DTDT)的优化反应条件为:n(三聚氯氰)∶n(双丙酮葡萄糖)∶n(Na OH)=0.9∶1∶1.7,在丙酮和水的混合体系中0℃下反应8h,产率73%。合成3-(2-(2-羟基苯基苯甲酮-4-氧基)-4-氯-1,3,5-三嗪-6-氧基)-1,2,5,6双异丙叉-α-D-葡萄糖(UV-DT)的优化条件为:n(DTDT)∶n(UV-0)∶n(Na OH)=1∶1.1∶1,在丙酮和水的混合体系中30℃下反应2h,产率74%。合成UV-DTM的优化条件为:每1mmol UV-DT与0.5m L盐酸(36%)在THF体系中25℃下反应5h,产率74%。UV-DTM的紫外吸收性能在240~400 nm内表现良好,水溶性得到大幅改善。  相似文献   

3.
2-羟基-4-甲氧基二苯甲酮-β-环糊精包合物的制备与表征   总被引:3,自引:0,他引:3  
罗维巍  宫红  姜恒 《化学研究》2006,17(1):35-37
采用研磨法合成了2-羟基-4-甲氧基二苯甲酮-β-环糊精包合物.用差示量热扫描分析、热重分析、红外分析、X射线衍射分析对包合物进行了鉴定.紫外光谱分析表明,包合没有改变2-羟基-4-甲氧基二苯甲酮的性质,包合物仍然具有吸收紫外线的能力.  相似文献   

4.
2-羟基-4-甲氧基二苯甲酮(紫外线吸收剂)与一氯乙酰氯反应制得功能中间体2-氯乙酰氧基-4-甲氧基-二苯甲酮(1);在碱性条件下1与羧甲基壳聚糖(CMC)在异丙醇中通过N-烷基化反应实现1在CMC上的接枝,合成了一系列新型CMC接枝物——CMC-g-1n(2-G,G=接枝率),其结构经UV,IR和XRD表征.并测试了2-G的吸湿性、保湿性以及溶解性.结果表明,2-G在311 nm处有最大紫外吸收;吸湿性随G的增大减小;保湿性随G的增大提高;2-G有较好的水溶性.  相似文献   

5.
聚芳醚醚酮酮(PEEKK)是继聚芳醚醚酮(PEEK)之后,由德国Hoechst公司开发出来的又一种全芳香结构热塑性耐高温特种工程塑料,由于PEEKK分子链规整性好,熔融温度高,加工成型非常困难,且具有极好的耐溶剂性,只能在浓硫酸等少数溶剂中可以溶解,使其应用受到了一定的限制,人们常常在主链上引入不同的大的基团(如萘环、二氮杂萘酮)、  相似文献   

6.
标题化合物C11H10N2O3是由咪唑啉-2,4-二酮、对甲氧基苯甲醛在微波辐射下反应而得, 反应在5分钟内完成。结构通过单晶X-射线衍射法测定,其晶体属三斜晶系,空间群P, Mr = 218.21, a = 5.346(1), b = 10.212(2), c = 10.368(2) ? ?= 72.34(2), ?= 75.35(2), ?= 78.09(2), V = 516.6(2) ?, Z = 2, Dc = 1.403 g/cm3, = 0.104 mm-1, F(000) = 228, R = 0.0442, wR = 0.1152。咪唑环与苯环之间的两面角为5.45, 分子之间存在氢键, 形成了网状结构。  相似文献   

7.
β-二酮化合物是一类重要的有机合成中间体,β-二酮化合物分子内酮式-烯醇式之间的异构化转变赋予其许多独特的光化学和配位化学性质。关于酮式-烯醇式之间的互变关系有许多研究[1,2,3],借助于其光致互变异构的光化学性质,β-二酮化合物可广泛地用作光稳定等功能材料[4]。同时,  相似文献   

8.
袁高清  李志发  江焕峰 《中国化学》2009,27(8):1464-1470
室温下,在一室电解池中,以n-Bu4NBr-DMF作电解质、镍为阴极、铝为阳极,恒电流电解二氧化碳与芳香酮(苯乙酮、对二苯甲酮、6-甲氧基-2-萘乙酮、4-甲基苯乙酮和4-甲氧基苯乙酮),可以得到相应的α-羟基羧酸(产率56%-90%)。实验结果显示,阴极材料、芳香族酮的结构以及电解条件(如电量、底物浓度、导电盐、溶剂和二氧化碳压力等)对目标产物的产率有很大影响;反应系统中质子剂(水)的存在将导致副产物频哪醇的生成。本文还根据循环伏安实验和合成实验结果简要地讨论了反应机理。  相似文献   

9.
本文以含有端基炔的芳硫醚为原料,碘苯二乙酯为氧化剂,氯化亚铜为催化剂,室温下反应30 min,合成了1,4-二(2-芳硫基苯基)-1,3-丁二炔化合物。通过1HNMR、13CNMR等对其进行了结构表征,并研究了其光学性质,以及作为紫外线吸收剂在紫外光固化涂料中的应用。结果表明:该类化合物能够有效吸收270~360 nm的紫外光,且光降解程度小,并具有与树脂、单体相容性好、无气味等特点。同时,合成的目标化合物在光固化过程中不参与自由基体系的固化,且增强了涂料及固化涂层的光稳定性,有益于紫外光固化涂料的存储,是一类具有发展前景的紫外光吸收剂。  相似文献   

10.
本工作合成了多种含不同过渡金属离子的络合物——2-[2,4-二羟基苯甲酰]苯甲酸钴、镍、锰金属盐.对它们进行了详细表征和光稳定能力进行了实际评价,结果表明这类化合物有很好的光稳定能力,并指出含锰离子的络合物具有最佳光稳定能力是由于锰离子对原有的分子内氢键结构破坏最小所致.  相似文献   

11.
硒芳香杂环化合物的微波固相合成   总被引:2,自引:2,他引:2  
许多含硒杂环化合物具有抗肿瘤、抗病毒等生物活性及超导性。微波技术由于能量利用率高,操作简便,无污染等优点,已在有机合成中得到了广泛的应用。本文采用微波辐射固相合成法合成了如下目标化合物:  相似文献   

12.
以乙酸锂、草酸亚铁、磷酸二氢铵为原料,利用微波法制备出锂离子正极材料磷酸亚铁锂,同时在不同的时间下研究其对反应物合成的影响.用X射线衍射技术、扫描电子显微镜等对产品的晶体结构进行表征,结果表明:微波合成法具有反应时间短、能耗小、合成效率高等优点,其合成的磷酸亚铁锂的晶体结晶度较好、粒度分布较均匀、晶粒比较完整;同时也证实了微波合成是一种比较好的合成方法.  相似文献   

13.
Titanium-incorporated ZSM-5 zeolites (Si/Al = 50–200 and Si/Ti = 70) were successfully synthesized in a one-step sol-gel process under microwave irradiation. The characteristics of Ti-ZSM-5 zeolites were investigated using X-ray power diffraction, UV/Vis-DRS, FT-IR spectroscopy and solid-state 27Al-NMR to monitor the physico-chemical properties. Simultaneously, the acidic properties were characterized by the NH3-TPD profile. The characterization results revealed that the Ti4+ and Al3+ ions were well incorporated into the framework of Ti-ZSM-5 zeolite. The prepared zeolite was moderately active but selective in the dehydration of methanol to dimethyl ether.  相似文献   

14.
From earlier experiments it was observed that the reactions of aryl fluoride functional aryl ether ketone oligomers (PEK) with m-aminophenol lead to poor levels of amine incorporation because of side-reactions. In this article, a method is presented to protect the m-aminophenol by converting it into a triarylimine group. This protected m-aminophenol was used together with 4-fluoro,4′-hydroxybenzophenone in a typical poly(aryl ether) synthesis. PEKs of different molecular weights were synthesized with number average molecular weights $\overline {M}_n$) of 2600, 4500, and 5400 g/mol. The deprotection of the triarylimine chain end was carried out by an acid treatment to afford a monofunctional aromatic amine end group, amenable towards copolymerization. © 1995 John Wiley & Sons, Inc.  相似文献   

15.
The crosslinkable sulfonated poly(ether ether ketone)s (SPEEKs) were synthesized by nucleophilic substitution reaction of diallyl bisphenol A, tert-butylhydroquinone, 4,4′-difluorobenzophenone and sodium 5,5′-carbonylbis(2-fluorobenzene-sulfonate). The SPEEKs with high intrinsic viscosity showed good solubility and could be cast into flexible and transparent membranes. The SPEEK membranes containing benzophenone (BP) and triethylamine (TEA) photo-initiator system were treated by UV light to promote crosslinking. The experimental results revealed that the crosslinked membrane with 10 min irradiation time showed the most potential as proton exchange membrane for direct methanol fuel cell applications. When the irradiation time increased from 0 to 10 min, the water uptake decreased from 29.1 to 26.1%, and the tensile modulus and the tensile strength enhanced sharply from 0.80 to 1.44 GPa and from 40.3 to 63.4 MPa, respectively. In addition, the methanol diffusion coefficient reduced sharply from 1.70 × 10−6 to 7.42 × 10−7 cm2/s with only slight sacrifice in the proton conductivity, which made the crosslinked membrane with 10 min irradiation time possess the highest selectivity.  相似文献   

16.
One new synthesis route was first designed to synthesize the biphenyl acid chloride (BPACl), and then a series of novel poly (aryl ether nitrile ether ketone ketone) (PENEKK)/poly (aryl ether nitrile ether ketone biphenyl ketone) (PENEKBK) copolymers with different controlled structure compositions were synthesized by electrophilic polycondensation and varying the molar ratio of BPACl to terephthaloyl chloride (TPC). The obtained PENEKK/PENEKBK copolymers were characterized by different physical and chemical techniques. The results showed, the copolymers with 10–50% molar contents of biphenyl moities exhibited good thermal properties with glass transition temperatures (Tgs) of 184–196°C, decomposition temperatures (Tds) of 498–515°C, and good solubility in organic solvents (N‐Methyl‐2‐pyrrolidone (NMP), N,N‐dimethylformamide (DMF), and DMSO), indicating that they would have good potential for solvent processing. The thin films of the polymers had tensile strengths of 93.6–101.5 MPa, Young's moduli of 3.03–3.32 GPa, elongations at break of 9–14%, indicating they were strong materials. The densities of the obtained polymers were 1.31–1.40 g/cm?3, which were far lower than those of some main inorganic materials (such as Fe, nearly 7.8 g/cm?3), indicating that they would have possible potential for substituting some inorganic materials used as high temperature materials in some areas due to the merits of lightweight. Thus, the copolymers with 10–50% molar contents of biphenyl moities were promising polymer materials. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   

17.
18.
Bis(4-oxybenzoic acid) tetrakis(phenoxy) cyclotriphosphazene (IUPAC name: 4-[4-(carboxyphenoxy)-2,4,6,6-tetraphenoxy-1,3,5,2λ5,4λ5,6λ5-triazatriphosphinin-2-yl]oxy-benzoic acid) was synthesized and direct polycondensed with diphenylether or 1,4-diphenoxybenzene in Eaton's reagent at the temperature range of 80–120°C for 3 hours to give aromatic poly(ether ketone)s. Polycondensations at 120°C gave polymer of high molecular weight. Incorporation of cyclotriphosphazene groups in the aromatic poly(ether ketone) backbone greatly enhanced the solubility of these polymers in common organic polar solvents. Thermal stabilities by TGA for two polymer samples of polymer series ranged from 390 to 354°C in nitrogen at 10% weight loss and glass transition temperatures (Tg) ranged from 81.4 to 89.6°C by DSC. © 1998 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 36: 1227–1232, 1998  相似文献   

19.
微波法煅烧高岭土及合成洗涤助剂4A沸石   总被引:10,自引:0,他引:10  
本文用微波法燃烧高岭土并合成4A沸石。与传统高温热处理法相比,微波法燃烧的高岭土其活化深度好,增白程度高,粒度细,能耗大为降低,显示了明显的优越性。本文还采用燃烧后的活性高岭土为原料,在微波辐射下进行4A沸石的合成,并用XRD、DTA、SEM、白度计、钙离子交换度等进行表征。与传统水热处理法相比,微波法所得样品在结晶度、白度和钙离子交换能力方面均优势,且大大地加快了沸石晶化反应速率。经动力学处理,  相似文献   

20.
A new monomer di(4‐carboxyphenoxy) tetrakis(4‐fluorophenoxy)cyclotriphosphazene 1 was synthesized in a two‐step reaction sequence. The direct polycondensation of 1 and/or 4,4′‐dicarboxydiphenylether with aromatic ethers was carried out in P2O5/methanesulfonic acid (Eaton's reagent) at 120 °C for 3 h to give two series of aromatic poly(ether ketone)s containing cyclotriphosphazene units. The effect of the introduction of the cyclotriphosphazene group on the solubility and thermal properties of these polymers was discussed with relation to the cyclotriphosphazene contents. © 2000 John Wiley & Sons, Inc. J Polym Sci A: Polym Chem 38: 2300–2305, 2000  相似文献   

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