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1.
合成己酸异戊酯的催化剂研究   总被引:3,自引:1,他引:3  
综述了氯化铁等Lewis酸 ,硫酸氢钠 ,硫酸钛 ,对甲苯磺酸 ,固体超强酸TiO2 /SO42 -,稀土固体超强酸SO42 -/TiO2 /La3 + ,磷钨杂多酸 ,TABP等几种不同催化剂催化合成了己酸异戊酯的实验结果。结果表明 :硫酸氢钠 ,磷钨杂多酸 ,TABP等 3种催化剂对合成己酸异戊酯的酯收率较高 ,具有实际应用价值。  相似文献   

2.
张兆贵 《天津化工》2009,23(2):22-23
综述了氯化铁、硫酸氢钠、稀土固体超强酸SO4^2-/TiO2/La^3-、硫酸铁铵、强酸性阳离子交换树脂、复合型固体超强酸、氨基磺酸、对甲苯磺酸、混合金属氧化物固载杂多酸、钨硅杂多酸催化合成马来酸二异戊酯的方法。指出氯化铁、硫酸氢钠和硅钨杂多酸是催化合成马来酸二异戊酯的良好催化剂。  相似文献   

3.
合成马来酸二异戊酯的催化剂研究   总被引:2,自引:0,他引:2  
综述了氯化铁、硫酸氢钠、稀土固体超强酸SO2-4/TiO2/La3-、硫酸铁铵、强酸性阳离子交换树脂、复合型固体超强酸、氨基磺酸、对甲苯磺酸、混合金属氧化物固载杂多酸、钨硅杂多酸催化合成马来酸二异戊酯的方法.指出氯化铁、硫酸氢钠和硅钨杂多酸是催化合成马来酸二异戊酯的良好催化剂.  相似文献   

4.
合成乙酸异戊酯的催化剂研究   总被引:15,自引:3,他引:12  
杨水金  肖继 《应用化工》2001,30(3):4-6,10
综述了浓硫酸 ,NaHSO4 ·H2 O、CuSO4 、FeCl3 ·6H2 O ,磺化聚苯乙烯 ,对甲苯磺酸 ,氨基磺酸 ,固体超强酸TiO/SO4 2 -,钨锗杂多酸 ,TiSiW12 O4 0 /TiO2 等十种不同催化剂催化合成了乙酸异戊酯的实验结果。结果表明 :TiSiW12 O4 0 /TiO2 和NaHSO4 ·H2 O两种催化剂对合成乙酸异戊酯的酯收率较高 ,具有实际应用价值  相似文献   

5.
采用固体超强酸SO4^2-/TiO2为催化剂合成了己酸异戊酯。考察了影响产品收率的多种因素,确定了最佳反应条件。  相似文献   

6.
陈群 《上海化工》2005,30(5):20-21
以稀土固体超强酸SO4^2-/TiO2/Sm^3 为催化剂合成了己二酸二异辛酯,考察了影响酯化反应的因素。实验结果表明,稀土固体超强酸SO4^2-/TiO2/Sm^3 催化活性高、性能稳定,是一种优良的醇化催化剂。  相似文献   

7.
刘慧娟  王启会 《山西化工》2005,25(4):7-8,10
采用稀土元素Nd^3+对固体超强酸SO4^2-/TiO2进行改性,以肉桂酸和异戊醇为原料合成肉桂酸异戊酯。考察了各种因素对酯化率的影响。实验结果表明:最佳反应条件为催化剂焙烧温度450℃,催化剂用量1.0g,醇酸摩尔比1:4,反应时间2h。该催化剂可再生重复多次使用,产品的酯化率达93.8%。  相似文献   

8.
《化工中间体》2003,(10):45-45
目前肉桂酸异戊酯(β-苯基丙烯酸异戊酯)是肉桂酸与异戊醇在浓硫酸催化下直接酯化而成,产品质量差,污染严重,改变催化剂成为研究重点。作者结合本身工作,综述了对甲苯磺酸,TiSiW12O8/TiO2,固体超强酸等几种不同催化剂合成肉桂酸异戊酯的实验结果。  相似文献   

9.
以TiC l4为原料,采用溶胶-凝胶法制备了纳米固体超强酸SO42-/TiO2催化剂,探讨了硫酸浸渍浓度、焙烧温度、焙烧时间对催化剂性能的影响。以纳米固体超强酸SO42-/TiO2为催化剂,由棓酸与异戊醇直接酯化合成棓酸异戊酯,研究了回流反应时间、催化剂用量、醇酸物质的量比对棓酸异戊酯收率的影响。较佳工艺条件为:醇酸物质的量比为10∶1,反应时间3 h,催化剂用量3%,棓酸异戊酯的收率可达70.44%。  相似文献   

10.
SO2-4/TiO2固体超强酸催化合成草酸二异戊酯的研究   总被引:1,自引:0,他引:1  
以SO2-4-/TiO2固体超强酸为催化剂,由草酸和异戊醇为原料合成了草酸二异戊酯,考察了催化剂活化温度、原料配比和催化剂用量对反应的影响以及催化剂的重复使用性.结果表明,SO2-4-TiO2固体超强酸催化活性高、催化速率快、化学稳定性好,重复使用性佳、无环境污染;在最佳反应条件下,草酸二异戊酯收率达到99.7%,产品的质量分数都达到99.9%以上.  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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17.
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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