间歇反应精馏合成乙酸异丙酯

以乙酸和异丙醇为原料通过间歇式反应精馏合成乙酸异丙酯,正交实验给出最佳合成条件为:回流比3、反应时间1.5h、乙酸与异丙醇的物质的量比1∶1.5、催化剂用量为乙酸体积2%,乙酸异丙酯的最大收率为92.8%。     

相转移催化合成乙酸异丙酯

利用相转移催化剂催化合成乙酸异丙酯，最佳反应条件如下：催化剂用量0．38g./0.1mol乙酸，醇酸比1：2，反应时间1h，收率94．16％。实验证明，相转移催化对该酯化反应是高效，低成本和实用的合成方法。     

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％。     

硫酸氢钠催化合成乙酸异丙酯的研究

采用一水硫酸氢钠作催化剂,合成了乙酸异丙酯。当酸醇摩尔比为2∶1,催化剂用量为异丙醇质量的10%,反应温度95℃,回流时间为1h时,产率可达94.16%。结果表明,该反应采用一水硫酸氢钠作催化剂,具有较高的活性。此合成方法是一种简便而又实用的方法。     

稀土固体超强酸SO2-4/TiO2/La3+合成氯乙酸异丙酯

以稀土固体超强酸SO4^2-／TiO2／La^3 为催化剂,氯乙酸与异丙醇为原料合成氯乙酸异丙酯,系统地研究了投料比、催化剂用量、反应时间诸因素对产品收率的影响。实验结果表明：SO4^2-／TiO2／La^3 是合成氯乙酸异丙酯的良好催化剂,在n(异丙醇)：n(氯乙酸)=3．0,催化剂的用量为氯乙酸质量分数的4．5％,环己烷的用量为反应物总摩尔分数的25％,反应时间4．0h,反应温度90～100℃,氯乙酸异丙酯的收率达到90．7％。     

SO42－/ZrO2/SBA-15催化丙烯和乙酸合成乙酸异丙酯的研究

水热合成了介孔材料SBA-15，并以其为载体负载固体超强酸SO₄^2－/ZrO₂，得到催化剂 SO₄^2－/ZrO₂/SBA-15，通过XRD对其进行表征。在固定床反应器中，以丙烯和乙酸为原料，研究该催化剂催化合成乙酸异丙酯的活性。对反应条件进行系统地考察，得出最佳反应条件：反应温度140 ℃,反应压力1.2 MPa,空速1 h^－1,n(C₃H₆)∶n(CH₃COOH)=3∶1。在此条件下乙酸异丙酯的产率最高可达79.6％。     

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。     

由乙酸和丙烯合成乙酸异丙酯的研究进展

以丙烯为原料,与乙酸反应合成乙酸异丙酯的技术路线,具有较好的应用前景,系统的总结了在不同催化剂作用下乙酸和丙烯合成乙酸异丙酯研究的最新进展。     

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。     

ASPEN PLUS模拟与优化乙酸异丙酯提浓塔

以试验数据为基础．采用ASPENPLUS建立乙酸异丙酯提浓塔的模型，并考察进料板位置、回流比、塔板数等操作条件对目标产物的影响。结果表明，当进料板位置2-17、回流质量比1．5。2．5、理论塔板数为25块时，提浓塔塔釜采出的低沸物的质量分数在O．02％以下。塔釜采出乙酸异丙酯的质量分数可达到98．68％；尤其当回流比为1．5时，比原操作条件的塔釜热负荷减少24％。     

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。