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1.
目的研究N-羟基琥珀酰亚胺生物素酯(BNHS)的制备及其稳定性研究。方法以D-(+)-生物素为原料,与N-羟基琥珀酰亚胺在N,N'-二环己基碳二亚胺作用下反应生成N-羟基琥珀酰亚胺生物素酯,用差示扫描量热法和热重分析研究分析N-羟基琥珀酰亚胺生物素酯的热稳定性和热分解过程。结果合成工艺的收率为79.7%以生物素计。在氮气氛(氮气流量为20 mL·min~(-1))、10 K·min~(-1)的升温条件下,N-羟基琥珀酰亚胺生物素酯在353℃发生剧烈分解,至500℃几乎分解完全。结论所用制备方法简单、产率良好,适合大量制备,且产物热稳定性好。  相似文献   

2.
以环氧氯丙烷(ECH)和三甲胺(TMA)为原料,在40 kHz超声辅助下合成了季铵盐型活性醚化剂环氧氯丙基三甲基氯化铵(GTA);GTA在超声辅助下与硬脂酸反应,合成了阳离子单酯表面活性剂N,N,N-三甲基-2-羟基-3-硬脂酰氧基丙基氯化铵(CMESA)。通过元素分析,IR等手段对CMESA进行了表征,并考察了反应温度,n(GTA)∶n(硬脂酸),pH和反应时间等因素对产率的影响。结果表明,CMESA的合适合成条件为:超声频率50 kHz,n(GTA)∶n(硬脂酸)=3∶1,反应温度70℃,反应时间4 h,此条件下CMESA的产率为94.90%。  相似文献   

3.
杨建洲  苗宗成  林里 《精细化工》2005,22(12):884-886,890
以自制的阳离子单酯表面活性剂氯化2-羟基-3-硬脂酰氧基丙基三甲基铵(CMESA)和硬脂酰氯为原料,经一步反应合成了阳离子双酯表面活性剂氯化2,3-二(硬脂酰氧基)丙基三甲基铵(CDESA)。研究了反应介质、反应时间和缚酸剂吡啶的用量对生成物CDESA收率的影响,通过元素分析、官能团分析和红外光谱确证其化学结构,最佳合成条件为:n(CMESA)∶n(硬脂酰氯)∶n(吡啶)=1∶1∶1,1,4-二氧六环为反应介质,回流加热反应3h,CDESA收率为93.1%。  相似文献   

4.
以生物素、紫杉醇和6-氨基己酸为原料,经酰化、水解、酯化反应等步骤合成具有长臂连接的标题化合物。在三乙胺催化下,生物素与N-羟基琥珀酰亚胺反应生成N-羟基琥珀酰亚胺生物素酯。在氯化亚砜、甲醇反应体系下,由6-氨基己酸合成6-氨基己酸甲酯。在三乙胺作用下,N-羟基琥珀酰亚胺生物素酯和6-氨基己酸甲酯反应生成生物素-氨基己酸甲酯;生物素-氨基己酸甲酯在Li OH·H2O作用下,水解反应得到6-生物素氨基己酸。以DMF为溶剂,在N,N'-二环己基碳二亚胺(DCC)、4-二甲氨基吡啶(DMAP)作用下,6-生物素氨基己酸与紫杉醇反应,生成标题化合物。标题化合物和重要中间体化合物采用IR、1HNMR、MS进行了表征。  相似文献   

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以N,N-二甲基十二烷基叔胺与1,4-丁二醇为原料两步合成季铵盐型双子表面活性剂12-4-12,通过单因素法确定N,N-二甲基十二烷基叔胺与1,4-二溴丁烷的最佳反应条件。双子表面活性剂12-4-12的最佳合成条件为:反应物摩尔比为n(N,N-二甲基十二烷基叔胺)∶n(1,4-二溴丁烷)=2.2∶1,溶剂为异丙醇,反应温度82℃,反应时间12 h,产率为95.8%。  相似文献   

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为克服阳离子染料上染腈纶时,容易存在染色不匀、色牢度不好的弊端,合成了一种新型的季铵盐型阳离子表面活性剂。先用N,N-二甲基丙二胺与硬脂酸通过酰胺化反应合成N,N-二甲基硬脂酰基丙二胺,然后再和苄基氯反应合成新型匀染剂,通过正交试验设计的方法确定了最佳合成工艺:投料物质的量比n(N,N-二甲基硬脂酰基丙二胺)∶n(苄基氯)=1∶1.0,温度75℃条件下,反应时间3.5h。该条件下合成匀染剂,产物收率为88.7%。用制备的匀染剂与匀染剂DC(即N,N-二甲基十八烷基苄基氯化铵)在相同的条件下对腈纶进行对比染色发现,该新型匀染剂比匀染剂DC匀染效果更好。  相似文献   

7.
9-芴甲醇与光气反应合成9-芴甲酯(FMOC-Cl),不经分离直接与N-羟基丁二酰亚胺反应,一锅法合成N-(9H-芴-9-甲氧羰基氧)丁二酰亚胺(FMOC-OSu),总收率95%,产品纯度98%。  相似文献   

8.
N-(α-苯氧基)十四酰牛磺酸钠的合成   总被引:1,自引:0,他引:1  
以α-溴代十四酸乙酯、苯酚、牛磺酸为原料,经W illiam son醚化,水解,催化酰化等反应制备了一种芳氧基作疏水基团支链的牛磺酸盐类表面活性剂,即N-(α-苯氧基)十四酰牛磺酸钠(SPTT)。研究了W illiam son醚化制备α-苯氧基十四酸乙酯的反应条件,考察了几种常用酰化方法对于合成N-(α-苯氧基)十四酰牛磺酸钠的可行性。研究结果表明,醚化反应的最佳条件为:n(α-溴代十四酸乙酯)∶n(苯酚)∶n(K2CO3)=1.05∶11∶,DMF为溶剂,用苯回流分水3 h,α-苯氧基十四酸乙酯的收率为78.3%;合成N-(α-苯氧基)十四酰牛磺酸钠(SPTT)的最佳方法是催化酰化法,即在二环己基碳二亚胺(DCC)和N-羟基丁二酰亚胺(NHS)的催化下,α-苯氧基十四酸与牛磺酸及碳酸钠反应,n(α-苯氧基十四酸)∶n(DCC)∶n(NHS)∶n(牛磺酸)∶n(碳酸钠)=1∶1∶1∶1.5∶1.5,收率为72.3%。中间体及产物经FTIR,1HNMR,ESI-MS等表征,符合结构特征。  相似文献   

9.
马威  刘勇  张淑芬 《化工学报》2010,61(11):2992-2998
2-(2′-羟基-5′-甲基苯基)-2H-苯并三唑(UV-P)经过羟基乙酰化、N-溴代丁二酰亚胺(NBS)溴代,合成了具有高反应活性的2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑。为提高目标产物产率和反应效率,分别对溶剂、引发剂、反应温度、反应时间、反应物投料比和反应底物浓度进行了研究。得出较优合成条件为:氮气保护下,四氯化碳为溶剂,偶氮二异丁腈(AIBN)引发,NBS与2-(2′-乙酰氧基-5′-甲基苯基)-2H-苯并三唑摩尔比1∶1,回流反应1h。在上述条件下,2-(2′-乙酰氧基-5′-溴甲基苯基)-2H-苯并三唑产率为60%。产物经过IR、1HNMR、MS分析证明结构正确。  相似文献   

10.
以聚异丁烯丁二酸酐,N,N-二甲基-1,3-丙二胺,3-氯-1,2-丙二醇为主要原料,经过酰亚胺化、季铵化两步反应,合成了聚异丁烯丁二酰亚胺阳离子季铵盐高分子乳化剂,并用红外光谱对其进行结构表征。测定了产品的极限乳化性能与储存稳定性能,结果表明,所合成聚异丁烯丁二酰亚胺阳离子季铵盐高分子乳化剂的乳化稳定性较好,极限乳化性能与储存稳定性能均优于聚异丁烯丁二酰亚胺(T152),适用于乳化炸药行业,具有很好的市场推广前景。  相似文献   

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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   

13.
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   

14.
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   

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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   

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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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