对硝基苯甲酸催化酯化研究进展

综述了对硝基苯甲酸催化酯化的研究情况，重点介绍了直接酯化法催化剂的进展，包括酸催化剂和非酸催化剂。认为固体超强酸催化活性高，使用寿命长，易与产物分离，不腐蚀设备，无环境污染；相转移催化剂应用较多，酯化收率较高。     

对甲苯磺酸催化合成邻硝基苯甲酸正丁酯

对甲苯磺酸作为正丁醇和邻硝基苯甲酸的酯化催化剂,性能优于硫酸。探讨并找到了较好的反应条件,酯化率可达９３．５８％     

钛酸四丁酯催化合成硝基卡因的研究

对硝基苯甲酸和N，N-二乙基乙醇胺在二甲苯溶液中，以直接酯化法合成硝基卡因。通过对催化剂种类、催化剂用量、反应时间等影响因素的考察，确定以钛酸四丁酯作为催化剂，催化剂用量为对硝基苯甲酸质量的3．5％，n(对硝基苯甲酸)：n(N，N-二乙基乙醇胺)=1：1，反应14h。硝基卡因的产率达到82．1％，比没有催化剂时产率提高11．8％。     

微波辐射下阳离子交换树脂催化合成对硝基苯甲酸乙酯

以对硝基苯甲酸和乙醇为原料,H-732强酸性阳离子交换树脂为催化剂,在微波辐射条件下合成对硝基苯甲酸乙酯,探讨了微波功率、醇酸摩尔比、催化剂用量、反应时间对产品产率的影响。结果表明,H-732强酸性阳离子交换树脂在微波辐射条件下对酯化反应有良好的催化能力;醇酸摩尔比为3∶1,催化剂用量为对硝基苯甲酸质量的20%,反应时间15 min,微波功率为250 W时,对硝基苯甲酸乙酯的产率最高为87.45%,催化剂可以重复使用,再生后催化性能保持良好。     

对硝基苯甲酸乙酯合成研究

为优化对硝基苯甲酸乙酯的合成工艺,考察了5种不同类型的催化剂对其收率及其纯度的影响,发现以硫酸氢钾为催化剂时收率最高,并对影响产率的诸因素进行了考察,得出最佳反应条件为:对硝基苯甲酸0.015mol,催化剂用量0.40 g,醇酸摩尔比4:1,反应温度84～85℃,反应时间2.5 h,酯化反应产率高达99.53%.     

增塑剂对硝基苯甲酸异辛酯合成新工艺

以对硝基苯甲酸和异辛醇为原料,采用颗粒状活性炭固载对甲苯磺酸作催化剂合成对硝基苯甲酸异辛酯,设计了四因素、三水平的正交实验,考察了影响反应的各种因素。实验结果表明,酯化反应的最佳条件:对硝基苯甲酸∶异辛醇=1∶2、催化剂用量为反应物酸质量的1.0%、回流温度、反应时间6 h,反应原料酸质量为0.10 mol时,带水剂甲苯40 mL,产率可达95.5%。     

对甲苯磺酸催化合成对硝基苯甲酸乙酯的研究

以对甲苯磺酸为催化剂,合成了对硝基苯甲酸乙酯。对影响产率的诸因素进行了考察,其最佳反应条件为:醇酸摩尔比4∶1,催化剂用量为醇酸总量9%,反应时间2.5h,反应温度81℃～85℃,酯化反应产率高达95.8%。     

TiO2／SO4^2——Al2O3催化合成对硝基苯甲酸乙酯的研究

以复合固体超强酸为催化剂,合成了对硝基苯甲酸乙酯,通过正交试验,考察了原料配比,催化剂用量、反应时间等因素对产物收率的影响,确定了酯化最佳条件：酸／醇比1：5,反应时间2h,催化剂用量为反应物质量的4％,该条件下,产物收率达97.6％。     

有机锡羧酸酯的合成及催化性能

制备了二苯基锡二对硝基苯甲酸酯，并用红外光谱、核磁共振测试技术，对其进行表征，同时将其作为催化剂用于合成氯乙酸正丁酯。研究结果表明二苯基锡对硝基苯甲酸酯具有良好的催化性能，酯化率为94．4％-97．0％，并可重复使用。     

硫酸氢钾催化合成对硝基苯甲酸乙酯

以硫酸氢钾为催化荆,合成对硝基苯甲酸乙酯,并对影响产率的诸因素进行了考察.其最佳反应条件为:对硝基苯甲酸0.015 mol、醇/酸物质的量比4:1、催化剂用量0.4 g、反应时间2.5 h、反应温度78～80℃,酯化反应产率高达99.49%.     

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。