硫酸氢钠催化乙酸异丙酯合成工艺的研究

本文以冰乙酸和异丙醇为原料合成乙酸异丙酯。主要考察催化剂种类、催化剂用量、醇酸物质的量比、反应时间、带水剂种类、带水剂用量对乙酸异丙酯产率的影响,确定合成乙酸异丙酯的最佳工艺条件。实验结果表明,相对于其它催化剂,硫酸氢钠催化高效且环保。乙酸异丙酯合成的最佳合成工艺条件为:反应时间为1.5 h,催化剂用量为1.5 g,醇酸物质的量比为1∶1.5,带水剂用量10 mL,此时乙酸异丙酯产率可达62.9%。     

连续反应精馏合成乙酸异丙酯

以乙酸和异丙醇为原料通过连续反应精馏合成乙酸异丙酯，实验研究了影响反应的因素，结果表明最佳合成条件为：酸醇比1：1．2，回流比3，异丙醇的进料流量2mL／min，硫酸用量为乙酸体积的2％，乙酸异丙酯的最大收率为92．5％。     

硫酸氢钠催化合成乙酸异丙酯

以自制的硫酸氢钠为催化剂，以冰乙酸与异丙醇为原料合成了乙酸异丙酯。最佳反应条件为：以0.2摩尔异丙醇为基准，醇酸摩尔比为1：1.5，催化剂用量为1.2g，反应温度控制在回流温度。酯收率最高可达到75.2％。     

异丙醇生产工艺研究进展

异丙醇是一种具有重大工业应用价值的化工产品,可用做化工原料和有机溶剂。详细介绍了异丙醇生产工艺路线,综述比较了丙烯直接水和法、硫酸间接水和法、丙酮加氢法、乙酸异丙酯加氢法、乙酸异丙酯酯交换法等异丙醇合成方法的优缺点。丙酮加氢法合成异丙醇的路线产率更高,经济性更好,提出了今后异丙醇生产工艺的发展方向。     

对甲苯磺酸六氟异丙酯的合成

以六氟异丙醇和对甲苯磺酰氯为原料,合成对甲苯磺酸六氟异丙酯。通过正交实验,分析了溶剂、投料比、反应温度和反应时间对产率的影响。结果表明,采用三乙胺为催化剂,溶剂为二氯甲烷,反应温度为0℃,投入六氟异丙醇与对甲苯磺酰氯的摩尔比为1∶1.5,反应时间为3 h,对甲苯磺酸六氟异丙酯收率为94.4%。     

乙酸异丙酯加氢催化剂的制备与性能研究

乙酸异丙酯通过催化加氢可以制备具有高附加值的异丙醇和乙醇。利用共沉淀法制备了一系列铜基催化剂,以锌为助剂,分别研究了催化剂制备方法、活性组分质量分数、反应条件对乙酸异丙酯加氢反应的影响。结果表明,将所制备的催化剂用于乙酸异丙酯加氢反应中,在反应温度为230℃、反应压力为7.0 MPa、液体空速为0.2 h~(-1)的反应条件下,乙酸异丙酯转化率可以达到98%以上,异丙醇和乙醇总产率达93%以上。     

乙酸异丙酯催化合成研究进展

对乙酸异丙酯合成的催化剂研究进展进行了报道,综述了液态酸催化剂、固体酸催化剂、离子交换树脂催化剂、杂多酸（盐）催化剂。对以乙酸与丙烯或异丙醇为原料合成乙酸异丙脂的合成方法,特别是对乙酸的转化率、乙酸异丙脂的选择性作了详细的介绍。     

活性炭固载酸性催化剂合成水杨酸异丙酯

以水杨酸和异丙醇为原料,采用颗粒状活性炭固载对甲苯磺酸作催化剂合成水杨酸异丙酯,考察影响反应因素,结果表明,酯化反应最佳条件为:n(水杨酸)∶n(异丙醇)=1∶3.0,催化剂用量1.5 g,为反应物总质量的4.6%,反应时间3.0 h,带水剂甲苯用量8 mL,此条件下,水杨酸异丙酯收率可达94.45%。     

负载型杂多酸催化剂的制备及其对催化合成乙酸异丙酯的性能研究

采用热回流浸渍法将Keggin型12-磷钨杂多酸负载到改性高岭土上,并利用X射线衍射(XRD)、傅立叶变换红外光谱(FT-IR)、扫描电子显微镜(SEM)等手段对催化剂进行了表征。考察了负载型磷钨杂多酸催化剂对乙酸、异丙醇催化合成乙酸异丙酯的最佳反应条件。结果表明:改性高岭土有助于磷钨酸更好的分散,负载后磷钨杂多酸的Keggin结构并未遭到破坏。所制备的催化剂对乙酸和异丙醇合成乙酸异丙酯的酯化反应具有很好的催化选择性。     

正交设计优化分壁式萃取精馏分离乙酸异丙酯-异丙醇的模拟研究

利用Aspen Plus模拟软件,以DMSO为萃取剂,采用分壁式萃取精馏对乙酸异丙酯和异丙醇共沸物进行分离模拟研究,采用正交设计对灵敏度分析结果进行进一步优化,得到乙酸异丙酯和异丙醇质量分数分别为99.44%和99.34%,回收萃取剂质量分数99.99%。分壁式萃取精馏过程相比于常规双塔萃取精馏再沸器热负荷降低7.74%,冷凝器热负荷降低22.81%,实现了有效节能。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。