难溶杂多酸盐催化合成肉桂酸苄酯的研究

以钨硅酸和三乙醇胺为原料首先合成了钨硅酸三乙醇胺盐,并首次用于催化合成肉桂酸苄酯的催化合成研究。实验结果表明：n(肉桂酸)：n(苄醇)=1．0：2．4,反应温度100℃,反应时间4h,催化剂用量为肉桂酸的0．4％,酯收率大于94％。该催化剂具有较高的催化活性,且不溶于醇,易于回收,可重复使用5次以上。     

新型共聚物催化剂在醋酸异丙酯合成中的应用

采用新型磺化聚苯乙烯-co-甲基丙烯酸丁酯P（St-co-BMA）代替传统的浓硫酸催化异丙醇与冰乙酸的酯化反应。实验结果表明，P（St-co-BMA）对醋酸异丙酯的合成反应具有较好的催化活性。醋酸异丙酯的产率与新型催化剂的用量有关，当m(催化剂)∶m(异丙醇)=0.2∶1.0、酯化反应时间5 h时，醋酸异丙酯产率可达到74%以上。合成的共聚物催化剂经5次使用后,使醋酸异丙酯产率仍可达68%。该催化剂可用稀硫酸再生，多次使用过的催化剂经再生后的催化活性与新制备的共聚物催化剂的催化活性相比几乎没有差别。     

微波辐射四丁基溴化铵催化合成肉桂酸苄酯

研究了以肉桂酸钠和氯化苄为原料，四丁基溴化铵作催化剂，采用微波辐射技术，在常压下直接合成肉桂酸苄酯，以及催化剂用量、微波辐射功率和辐射时间对酯产率的影响。最适宜的反应条件为：当n(肉桂酸钠)／n(氯化苄)为1：1．2时，四丁基溴化铵的用量1．0g，微波功率300W，辐射25min，产率达83％以上。     

肉桂酸苄酯的合成研究

以十六烷基三甲基氯化铵为相转移催化剂催化合成肉桂酸苄酯,考察了催化剂、温度、时间和物料配比等因素对反应的影响。实验结果表明,十六烷基三甲基氯化铵是一种有效的催化剂,在最佳反应条件下,产物收率可迭86．0％。最佳反应条件是：n(肉桂酸钠)：n(氯化苄)为1：1.2,催化剂的用量为0．8g,反应时间3．0h,反应温度95℃。通过IR、^1HNMR和MS对产物结构进行了表征。     

KF/γ-Al2O3型固体超强碱催化合成肉桂酸的研究

苯甲醛与乙酐的Perkin反应合成肉桂酸，首次采用KF/γ-Al2O3固体超强碱催化剂，降低了反应温度，明显缩短了反应时间，最佳反应条件为n(苯甲醛)：n(乙酐)=1．0：3．0，反应时间1．5h，反应温度160℃，催化剂用量为苯甲醛质量的0．5％，所得的肉桂酸的产率可达81％以上。该催化剂具有较高的催化活性，易于回收，可重复使用5次以上。     

微波辐射四丁基氯化铵催化合成肉桂酸苄酯

本文研究了以肉桂酸钠和氯化苄为原料,四丁基氯化铵作催化剂,采用微波辐射技术,在常压下直接合成肉桂酸苄酯,以及催化剂用量、微波辐射功率和辐射时间对酯产率的影响。最适宜的反应条件为:当n(肉桂酸钠)∶n(氯化苄)=1∶1.2时,四丁基氯化铵的用量1.0g/0.05mol肉桂酸钠,微波功率300W,辐射25min,产率达84%以上。     

微波辐射十六烷基三甲基溴化铵催化合成肉桂酸苄酯

以肉桂酸钠和氯化苄为原料,十六烷基三甲基溴化铵作催化剂,采用微波辐射技术,在常压下直接合成肉桂酸苄酯,考察了催化剂用量、微波辐射功率和辐射时间对酯产率的影响。最适宜的反应条件为:当n(肉桂酸钠)∶n(氯化苄)=1∶1.2时,十六烷基三甲基溴化铵的用量1.0g,微波功率300W,辐射30min,产率达80%以上。     

微波辐射下肉桂酸苄酯的催化合成

以肉桂酸钠和氯化苄为原料,二乙胺作催化剂,采用微波辐射技术,在常压下直接合成肉桂酸苄酯,考查了催化剂用量、微波辐射功率和辐射时间对酯产率的影响。最适宜的反应条件为:当n(肉桂酸钠)∶n(氯化苄)=1∶3.4时,二乙胺的用量1.0mL,微波功率450W,辐射12min,产率达85%以上。     

磷钨酸催化合成苹果酯

探讨磷钨酸对苹果酯合成反应的催化活性,研究了带水剂用量、催化剂用量、乙酰乙酸乙酯与乙二醇的物质的量之比、反应时间等因素对产品收率的影响。实验表明：磷钨酸是合成苹果酯的优良催化剂,在n(乙酰乙酸乙酯):n(乙二醇)为1：1．5,催化剂用量为反应物总量的0．5%,环己烷作带水剂,反应时间为1．0h的优化条件下,苹果酯的收率可达82．2％。     

硫酸氢钾催化合成肉桂酸异戊酯

应用硫酸氢钾为催化剂,肉桂酸与异戊醇为原料,催化合成了肉桂酸异戊酯,考察了物料配比、催化剂用量和反应时间对酯产率的影响,以及催化剂的重复使用性能.研究结果表明:硫酸氢钾具有较高的催化活性,易于回收且可重复使用;最佳反应条件为n(肉桂酸)∶n(异戊醇)∶n(催化剂)=1∶19∶0.74,反应时间3 h;所得产品肉桂酸异戊酯的收率为96.3%.与传统方法相比,可缩短反应时间,催化剂用量少,且工艺简单.     

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。