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合成β-溴代乙基苯新工艺研究 总被引:2,自引:0,他引:2
在反应介质石油醚中,苯乙烯与溴化氢在催化剂作用下发生自由基加成反应合成β-溴代乙基苯。考察了溶剂配比、反应温度、反应时间对产品收率的影响,结果表明:V(石油醚):V(苯乙烯)=5:1,反应温度60℃.反应时间3~5h为最适宜条件.在该条件下产物收率达91%。 相似文献
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苯基丁基醚的相转移催化合成研究 总被引:1,自引:0,他引:1
在相转移催化剂存在下,以苯酚、溴丁烷为原料合成苯基丁基醚。分别研究了反应温度、反应时间、原料配比、催化剂用量等条件对合成反应的影响,确定了最佳工艺条件,该方法合成苯基丁基醚的最佳工艺条件是:反应温度85℃、反应时间4h、n(苯酚):n(溴丁烷)=1:1.10;n(苯酚):n(氢氧化钾)=1:1.15;相转移催化剂用量为0.5g(基于0.1mol苯酚),苯基丁基醚的收率可达到95.20%以上,产品纯度w(苯基丁基醚)为98.5%。 相似文献
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研究了以苯甲酰氯和哌啶醇为原料直接缩合合成苯甲酸哌啶醇酯受阻胺光稳定剂(HALS)时反应温度、反应时间、原料配比等条件对合成反应的影响,确定了最佳工艺条件。最适宜的工艺条件是:反应温度95℃、反应时间6h、原料摩尔比n(哌啶醇):n(苯甲酰氯)为1:1.4,溶剂用量为70mL(相对于0.1mol哌啶醇),苯甲酸哌啶醇酯的收率为91.05%,产品纯度98.5%。 相似文献
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以磷钨钼杂多酸为催化剂,无水乙醇为溶剂,苯甲醛、乙酰乙酸乙酯、尿素为原料,合成了4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮,系统研究了催化剂用量、反应温度、反应时间、原料配比诸因素对产品收率的影响。实验表明:磷钨钼杂多酸是合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮的良好催化剂。确定的最优合成工艺条件为:尿素37.5mmol时,n(苯甲醛):n(乙酰乙酸乙酯):n(尿素)=1:1.2:1.5,催化剂用量为反应物料总质量的1.5%,反应温度为60℃,反应时间1.0h。在此条件下,产品收率可达44.6%. 相似文献
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高效渗透促进剂月桂氮卓酮的合成研究 总被引:2,自引:0,他引:2
以ε-己内酰胺与1-溴代十二烷为原料,采用氟化钾协助的相转移催化方法合成了高效渗透促进剂月桂氮卓酮,讨论了催化剂用量,助催化剂(KF)用量,反应时间和温度,碱基,溶剂选择等对反应收率的影响,通过正交试验确定优化合成条件为:催化剂(PTC-2)用量0.012mol,KF用量0.090mol,(-己内酰胺和1-溴代十二烷的用量均为1.0mol(投料摩尔比为1:1),反应温度60摄氏度,反应时间8h,产物收率≥93.9%,含量98.9%,并经理化检测和光谱确证。 相似文献
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研究了以对硝基苯胺为原料,在催化剂的作用下,合成2-氨基-6-硝基苯并噻唑。其适宜的工艺条件为:n(对硝基苯胺):n(硫氰酸胺):n(苯)=1:1.15:6.5,反应温度为80-85℃,反应时间为10h;n(对硝基苯基硫脲):n(催化剂)=1:0.093,室温反应,反应时间为2h。产品收率为64.5%,纯度≥99%。 相似文献
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以氯化苄、碳酸钙为主要原料,在相转移催化剂的作用下水解得到苯甲醇,通过单因素实验,得到优化的工艺条件为:氯化苄:碳酸钙:水:催化剂(质量比)=1:1:5.2:0.02,反应温度:100℃,反应时间:12h,其收率可达94.4%,产品经气相色谱定量分析,纯度可达到99.3%。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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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Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US
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
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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