乙酰乙酸乙酯与乙二醇在活性炭负载磷钨酸催化剂上缩合反应

表面活性剂处理的活性炭(C)过量浸渍负载磷钨杂多酸(PW)制备活性炭负载磷钨酸催化剂(PW/C);氨气程序升温脱咐对催化剂酸性质表征,结果显示,负载质量分数为30%,催化剂30%PW/C具有最大酸量。反应测试表明,磷钨酸负载量为30%时催化剂具有最大活性,苹果酯收率为87.5%,适宜的原料配比n(乙酰乙酸乙酯)∶n(乙二醇)=1∶1.5,最佳反应温度80℃,最佳反应时间30 m in,表面活性剂处理过的催化剂连续使用9次,苹果酯的收率保持在85%以上。     

活性炭负载磷钨酸催化合成苯乙醛乙二醇缩醛

以活性炭负载磷钨酸作催化剂,对以苯乙醛和乙二醇为原料合成苯乙醛乙二醇缩醛的反应条件进行了研究.实验结果表明:活性炭负载磷钨酸是合成苯乙醛乙二醇缩醛的良好催化剂,较系统地研究了醛醇摩尔比、催化剂用量、反应时间诸因素对产率的影响.最佳反应条件为:n(苯乙醛)∶n(乙二醇)∶n(催化剂)=1∶1.2∶0.0034,带水剂环己烷12ml,反应时间90min.上述条件下,苯乙醛乙二醇缩醛的产率可达90.24%     

活性炭负载磷钨酸催化合成二甲基丙烯酸丁二醇酯

用活性炭负载磷钨酸作催化剂，高效合成了二甲基丙烯酸丁二醇酯。比较了三种不同的负载方法对催化活性的影响，筛选出活性最高的负载方法。考察了酯化反应条件对催化活性的影响，得出优化合成条件：n(酸)∶n(醇)＝2.3∶1，催化剂用量为总反应物质量的2.5%，带水剂甲苯用量为25%，阻聚剂对苯二酚用量为0.25 %，反应温度(100～110) ℃，反应时间约为1.5 h，酯化率可达到95.0%，催化剂重复使用6次，酯化率仍保持在85.0%以上。     

NPS-1负载磷钨酸催化合成4-叔丁基-2-(α-甲基苄基）苯酚

以介孔分子筛NPS-1负载12-磷钨酸杂多酸为催化剂,4-叔丁基苯酚和苯乙烯为原料,合成4-叔丁基-2-（α-甲基苄基）苯酚（t-BAMBP）。采用正交实验研究介孔材料NPS-1负载12-磷钨酸对t-BAMBP合成反应的催化活性,考察反应温度、反应时间、原料配比和催化剂用量对t-BAMBP收率的影响。优化的工艺条件为：反应温度70 ℃,反应时间30 min,n（苯乙烯）∶n(4-叔丁基苯酚)=1.3∶1,催化剂用量为4-叔丁基苯酚质量的0.2%,t-BAMBP收率70.3%。     

活性炭负载磷钨酸催化合成丙二酸二乙酯的研究

以丙二酸和乙醇为原料，采用活性炭负载磷钨酸作催化剂合成丙二酸二乙酯。考察了催化剂用量、酸醇物质的量比、带水剂用量以及反应时间等因素对收率的影响。确定最佳酯化反应条件：n(丙二酸n(乙醇）∶n(催化剂）＝1∶3∶0.007，带水剂甲苯15 mL，反应时间90 min。收率可达96.25%。     

活性炭负载磷钨酸催化合成环己酮乙二醇缩酮的研究

用活性炭负载磷钨酸催化合成环己酮乙二醇缩酮,考察了催化剂的用量、反应温度、反应时间、酮醇物质的量比及带水剂等因素对反应的影响,实验表明,在n( 环己酮)∶n(乙二醇)=1∶1.8,催化剂用量为反应物料总质量分数的0.84%、环己烷为带水剂和反应时间30 min条件下,环己酮乙二醇缩酮的收率可达88.73%。催化剂可重复使用。     

活性炭负载磷钨酸催化合成烷基多苷

用活性炭负载磷钨酸为催化剂,用二步法合成了十二烷基多苷(APG)。丁苷化反应的最优工艺条件是:磷钨酸负载量20%,用量为葡萄糖的5%,n(葡萄糖)∶n(丁醇)为5∶1,温度120℃,反应时间2 h。催化剂可以重复使用。在n(十二醇)∶n(葡萄糖)为2.5∶1时,可以用水萃取分离APG,得到的产品色浅且稳定。APG在水溶液中的临界胶束浓度为65.5 mg/L,表面张力为25.2 mN/m,泡沫力为160 mm,5 min后泡沫高度为158 mm。     

H6P2W18O62/SiO2催化合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮

采用溶胶凝胶法将Dawson型磷钨酸负载于SiO2上,制备的负载型催化剂H6P2W18O62/SiO2,通过FTIR、XRD、SEM、TGA对其进行表征。结果表明,该Dawson型磷钨酸可以较均匀地分散在SiO2载体上,且在催化合成4-苯基-6-甲基-5-乙氧羰基-3,4-二氢嘧啶-2(H)-酮的Biginelli反应中表现出较高的催化活性。最佳反应条件为:在固定苯甲醛用量为0.04 mol条件下,n(苯甲醛)∶n(乙酰乙酸乙酯)∶n(尿素)=1∶1.5∶1.5,催化剂用量为反应物总质量的2.0%,反应温度为80℃,反应时间为75 min。在最优条件下,产品平均收率可达82.3%,催化剂重复利用10次后收率仍达57.2%。     

杂多酸催化合成4-叔丁基-2-(α-甲基苄基)苯酚

以4-叔丁基苯酚和苯乙烯为原料,Keggin型杂多酸12-磷钨酸为催化剂,合成4-叔丁基-2-(α-甲基苄基)苯酚(t-BAMBP),考察了原料摩尔比、反应时间、反应温度以及催化剂用量对t-BAMBP收率的影响。结果表明,较优工艺条件为:n(苯乙烯)∶n(4-叔丁基苯酚)=1.3∶1,反应时间为90 min,反应温度为90℃,催化剂用量为1%[m(12-磷钨酸)∶m(4-叔丁基苯酚)],4-丁基苯酚转化率为95%,t-BAMBP收率为62.4%。     

活性炭负载磷钨酸催化1-癸烯齐聚反应的研究

使用活性炭负载磷钨酸催化剂,对1-癸烯齐聚反应进行研究,考察磷钨酸负载量、催化剂活化温度、活化时间、反应温度、反应压力和反应时间对1-癸烯转化率的影响。确定最佳的工艺条件为:磷钨酸负载质量分数37%,催化剂活化温度200℃,活化时间3 h,反应温度180℃,反应压力0.5 MPa,反应时间4 h。在此条件下,对聚烯烃合成油的物化性能进行研究,结果表明,采用活性炭负载磷钨酸催化剂催化1-癸烯齐聚合成油100℃黏度为4.60 mm2·s-1,黏度指数为126,凝点为-58℃,1-癸烯转化率为83.5%。     

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。