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1.
改进了苯胺盐酸盐催化合成双胺芴的方法,利用甲苯除水促进了反应速度,降低了反应温度,提高了反应产率;并探讨了不同酸苯胺盐的催化效果及催化剂用量、苯胺用量、反应温度、反应时间等因素对双胺芴合成产率的影响.实验结果表明,当n(苯胺)n∶(PhNH2·HCl)n∶(芴酮)=101∶.51∶,温度130℃,反应6 h时,双胺芴的产率达88.2%.并且过量苯胺得到回收,减少了对环境的污染,有利于双胺芴工业化生产.  相似文献   

2.
用四甲基氢氧化铵作相转移催化剂,可在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺。研究了多种反应因素对目的产物产率的影响,各影响因素对产率提高的重要性次序依次是:反应物摩尔比>氢氧化钠溶液用量>反应时间>催化剂用量>氢氧化钠溶液质量分数>反应温度。提出了常压下催化合成目的产物的最佳工艺条件是:n(苯胺)∶n(溴乙烷)=1∶2.50,催化剂用量0.40 mL,在45 mL 质量分数为0.50的氢氧化钠溶液中,反应温度65℃,常压反应7 h,产品产率90.6%。  相似文献   

3.
田庆伟 《当代化工》2005,34(2):109-111
用聚乙二醇800作相转移催化剂,在常压下由苯胺和溴乙烷合成了N,N-二乙基苯胺,研究了多种反应因素对目的产物产率的影响,提出了常压催化合成目的产物的最佳工艺条件是:n(苯胺):n(溴乙烷)=1:1.50,催化剂用量0.40g,在40mL质量分数为50%的氢氧化钠溶液中,反应温度65℃,常压反应7h,产品收率71.5%。  相似文献   

4.
芳胺及其衍生物在现代化学的许多领域扮演着中心角色,9,9-双(3-甲基-4-氨基苯基)芴是芳胺的一种,采用工业芴、氯仿及邻甲基苯胺为原料,通过两步法对其进行合成.分别考察了反应温度、反应时间、物料配比等因素对反应的影响,确定了较佳的合成工艺,通过熔点及核磁氢谱对产物进行表征.  相似文献   

5.
谢贤清  熊云奎  严楠  许招会 《现代化工》2011,31(Z1):264-266
以自制的9,9-双羟甲基芴(BHMF)和苯甲酰氯为原料,以三乙胺为吸收剂合成了9,9-双(苯甲酸甲酯基)芴,采用了红外光谱和核磁共振氢谱等分析测试手段对产品进行了结构表征并逐一归属。考察了原料配比、反应时间、反应温度及吸收剂用量等因素对9,9-双(苯甲酸甲酯基)芴收率的影响。实验结果表明,最佳工艺条件为:0.1 mol BHMF,n(BHMF)∶n(苯甲酰氯)=1.0∶3.0,三乙胺吸收剂为60 mL,反应温度10℃,反应时间4.0 h,在此条件下9,9-双(苯甲酸甲酯基)芴收率可达85.4%。  相似文献   

6.
以煤焦油分离产品芴为原料,通过溴代、氧化反应制得2-溴芴酮,对氧化过程中不同溶剂及用量、碱的用量、反应时间对产率的影响进行了优化选择。较佳的反应条件为:四氢呋喃作溶剂,m(2-溴芴)∶m(四氢呋喃)=1∶5.5,n(2-溴芴)∶n(氢氧化钾)=10∶1,室温反应5h,2-溴芴酮的产率大于98.0%,质量分数高于98.0%。产物的结构通过红外和核磁共振波谱进行了表征。  相似文献   

7.
用正癸基三乙基溴化铵作为相转移催化剂,在常压下由苯胺和溴乙烷合成N,N-二乙基苯胺,研究了多种因素对目的产物产率的影响,提出了常压催化合成目的的产物的最佳工艺条件是:n(苯胺):n(溴乙烷)=1:1.75,相转移催化剂用量1%(摩尔分数),在35%的氢氧化钠溶液中,反应温度85℃,常压反应5 h,产品产率82.4%.  相似文献   

8.
描述了几种带有取代基的的双胺芴化合物的合成方法,由于这些化合物具有热稳定性光稳定性、和较好的溶解性,因此是合成芴类发光材料的重要中间体,也可以合成耐热聚酰亚胺树脂等材料。这些化合物主要的合成方法为取代芴酮与苯胺在酸催化剂作用下发生缩合反应,生成9-位双胺芴类化合物。反应条件为苯胺芴酮物质的量比为8~10,苯胺盐酸盐为催化剂,反应温度130~150℃,反应时间5~6h,收率多为80%~90%。  相似文献   

9.
4-氯苯异氰酸酯绿色合成工艺研究   总被引:1,自引:1,他引:0  
用"绿色化学品"碳酸二甲酯(DMC)代替光气与4-氯苯胺反应合成4-氯苯异氰酸酯.研究了反应物质量比、温度、时间、催化剂用量对合成目标物产率的影响,建立了获得目标产物的最佳工艺条件.实验结果表明,ZnO催化剂用量为0.06 g,物料比n(DMC)∶n(4-氯苯胺)为8∶1,反应温度80℃,反应时间6 h,收率为62.1...  相似文献   

10.
研究了不同碳链长度的脂肪酸与N-甲基二乙醇胺的酯化反应。以月桂酸为原料,通过正交实验考察了反应温度、物料摩尔比、回流液温度、催化剂用量等因素对该酯化反应的影响,确定了较优的工艺条件为:反应温度200℃,n(月桂酸)∶n(N-甲基二乙醇胺)=1.8∶1.0,回流液温度70℃,催化剂用量(相对于反应原料的质量)0.3%。在该工艺条件下,酯化产物中甲基二乙醇胺双月桂酸酯(双酯胺)的质量分数可达98%以上。并对正辛酸、正癸酸、棕榈酸和硬脂酸与N-甲基二乙醇胺的酯化反应条件进行了优化,得到的产物中双酯胺的质量分数达98%以上。采用IR和1HNMR对双酯胺的结构进行了表征。  相似文献   

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12.
Vismiones and ferruginins, representatives of a new class of lypophilic anthranoids from the genusVismia were found to inhibit feeding in larvae of species ofSpodoptera, Heliothis, and inLocusta migratoria.  相似文献   

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14.
Despite its industrial importance, the subject of freeze-thaw (F/T) stability of latex coatings has not been studied extensively. There is also a lack of fundamental understanding about the process and the mechanisms through which a coating becomes destabilized. High pressure (2100 bar) freezing fixes the state of water-suspended particles of polymer binder and inorganic pigments without the growth of ice crystals during freezing that produce artifacts in direct imaging scanning electron microscopy (SEM) of fracture surfaces of frozen coatings. We show that by incorporating copolymerizable functional monomers, it is possible to achieve F/T stability in polymer latexes and in low-VOC paints, as judged by the microstructures revealed by the cryogenic SEM technique. Particle coalescence as well as pigment segregation in F/T unstable systems are visualized. In order to achieve F/T stability in paints, latex particles must not flocculate and should provide protection to inorganic pigment and extender particles. Because of the unique capabilities of the cryogenic SEM, we are able to separate the effects of freezing and thawing, and study the influence of the rate of freezing and thawing on F/T stability. Destabilization can be caused by either freezing or thawing. A slow freezing process is more detrimental to F/T stability than a fast freezing process; the latter actually preserves suspension stability during freezing. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004 in Chicago, IL. Tied for first place in The John A. Gordon Best Paper Competition.  相似文献   

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In 2002–2004, we examined the flight responses of 49 species of native and exotic bark and ambrosia beetles (Coleoptera: Scolytidae and Platypodidae) to traps baited with ethanol and/or (−)-α-pinene in the southeastern US. Eight field trials were conducted in mature pine stands in Alabama, Florida, Georgia, North Carolina, and South Carolina. Funnel traps baited with ethanol lures (release rate, about 0.6 g/day at 25–28°C) were attractive to ten species of ambrosia beetles (Ambrosiodmus tachygraphus, Anisandrus sayi, Dryoxylon onoharaensum, Monarthrum mali, Xyleborinus saxesenii, Xyleborus affinis, Xyleborus ferrugineus, Xylosandrus compactus, Xylosandrus crassiusculus, and Xylosandrus germanus) and two species of bark beetles (Cryptocarenus heveae and Hypothenemus sp.). Traps baited with (−)-α-pinene lures (release rate, 2–6 g/day at 25–28°C) were attractive to five bark beetle species (Dendroctonus terebrans, Hylastes porculus, Hylastes salebrosus, Hylastes tenuis, and Ips grandicollis) and one platypodid ambrosia beetle species (Myoplatypus flavicornis). Ethanol enhanced responses of some species (Xyleborus pubescens, H. porculus, H. salebrosus, H. tenuis, and Pityophthorus cariniceps) to traps baited with (−)-α-pinene in some locations. (−)-α-Pinene interrupted the response of some ambrosia beetle species to traps baited with ethanol, but only the response of D. onoharaensum was interrupted consistently at most locations. Of 23 species of ambrosia beetles captured in our field trials, nine were exotic and accounted for 70–97% of total catches of ambrosia beetles. Our results provide support for the continued use of separate traps baited with ethanol alone and ethanol with (−)-α-pinene to detect and monitor common bark and ambrosia beetles from the southeastern region of the US.  相似文献   

18.
Halyomorpha halys (Stål) (Pentatomidae), called the brown marmorated stink bug (BMSB), is a newly invasive species in the eastern USA that is rapidly spreading from the original point of establishment in Allentown, PA. In its native range, the BMSB is reportedly attracted to methyl (E,E,Z)-2,4,6-decatrienoate, the male-produced pheromone of another pentatomid common in eastern Asia, Plautia stali Scott. In North America, Thyanta spp. are the only pentatomids known to produce methyl 2,4,6-decatrienoate [the (E,Z,Z)-isomer] as part of their pheromones. Methyl 2,4,6-decatrienoates were field-tested in Maryland to monitor the spread of the BMSB and to explore the possibility that Thyanta spp. are an alternate host for parasitic tachinid flies that use stink bug pheromones as host-finding kairomones. Here we report the first captures of adult and nymph BMSBs in traps baited with methyl (E,E,Z)-2,4,6-decatrienoate in central Maryland and present data verifying that the tachinid, Euclytia flava (Townsend), exploits methyl (E,Z,Z)-2,4,6-decatrienoate as a kairomone. We also report the unexpected finding that various isomers of methyl 2,4,6-decatrienoate attract Acrosternum hilare (Say), although this bug apparently does not produce methyl decatrienoates. Other stink bugs and tachinids native to North America were also attracted to methyl 2,4,6-decatrienoates. These data indicate there are Heteroptera in North America in addition to Thyanta spp. that probably use methyl 2,4,6-decatrienoates as pheromones. The evidence that some pentatomids exploit the pheromones of other true bugs as kairomones to find food or to congregate as a passive defense against tachinid parasitism is discussed.  相似文献   

19.
收集了2007年7月~2008年6月世界塑料工业的相关资料,介绍了2007~2008年国外塑料工业的发展情况,提供了世界塑料产量、消费量及全球各类树脂的需求量及产能情况.按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(尼龙、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、特种工程塑料(聚苯·硫醚、液晶聚合物、聚醚醚酮)、通用热固性树脂(酚醛、聚氨酯、不饱和聚酯树脂、环氧树脂)不同品种的顺序,对树脂的产量、消费量、供需状况及合成工艺、产品应用开发、树脂品种的延伸及应用的进一步扩展等技术作了详细介绍.  相似文献   

20.
收集了2005年7月~2006年6月国外塑料工业的相关资料,介绍了2005—2006年国外塑料工业的发展情况。提供了世界塑料产量、消费量及全球各类树脂生产量以及各国塑料制品的进出口情况。作为对比,介绍了中国塑料的生产情况。按通用热塑性树脂(聚乙烯、聚丙烯、聚苯乙烯、聚氯乙烯、ABS树脂)、工程塑料(聚酰胺、聚碳酸酯、聚甲醛、热塑性聚酯、聚苯醚)、通用热固性树脂(酚醛、聚氨酯、不饱和树脂、环氧树脂)、特种工程塑料(聚苯硫醚、液晶聚合物、聚醚醚酮)的品种顺序,对树脂的产量、消费量、供需状况及合成工艺、产品开发、树脂品种的延伸及应用的扩展作了详细的介绍。  相似文献   

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