HClO_4-SiO_2催化合成乙酸环己酯

以HClO4-SiO2为催化剂,乙酸和环己醇为原料,环己烷为带水剂,催化合成乙酸环己酯。研究了酸醇比、催化剂用量、反应时间和带水剂用量等因素对酯化率的影响。确定最佳反应条件为:n(乙酸):n(环己醇)=1:1.1,催化剂用量为乙酸质量的4%,反应时间为3 h,酯化率达到94.4%。催化剂连续使用6次,催化活性无明显降低。     

六水合三氯化铝催化合成乙酸环己酯

以乙酸和环己醇为原料,六水合三氯化铝为催化剂催化合成了乙酸环己酯。在优化反应条件下,酯收率达78.8%。优化反应条件如下:n(乙酸)=200 mmol,n(乙酸)∶n(环己醇)=1.0∶1.5,催化剂用量为1.5 g,带水剂环己烷用量为10 mL,反应温度为106~124℃。实验结果表明催化剂催化性能高,反应条件温和,方法简单,收率优良。     

复合型过渡金属盐催化合成乙酸环己酯

以乙酸和环已醇为原料,复合型过渡金属盐为酯化催化剂合成乙酸环已酯。结果表明:在催化剂为CuSO4／Fe2(SO4)3且两者的质量比为1:1,乙酸与环己醇的摩尔比为1:1．1,催化剂用量为反应物总质量的2．5％,反应时间为150min,反应温度为110℃,带水剂己烷为15mL时,乙酸环己酯的产率可以达到94．49％。     

氯化锡催化合成乙酸环己酯

以环境友好试剂氯化锡为催化剂,对乙酸与环己醇反应合成乙酸环己酯进行了研究。考察了催化剂的用量、醇酸物质的量比、带水剂用量、反应时间等因素对乙酸环己酯收率的影响。实验结果表明催化剂催化性能好,具有稳定性高,反应条件温和,后处理简单,无环境污染,能重复使用的特点。最佳反应条件是:醇酸物质的量比是1.0∶2.5,催化剂用量为乙酸质量的1.3%,带水剂环己烷15mL,反应时间是180min。优化反应条件下,酯的收率最高达70.1%。     

N-甲基吡咯烷酮硫酸氢盐催化合成己二酸二异辛酯

以新型离子液体N-甲基吡咯烷酮硫酸氢盐([Hnmp]HSO4)为催化剂,己二酸和异辛醇为原料,环己烷为带水剂,对己二酸二异辛酯的酯化反应进行了研究,重点考察了醇酸摩尔比、催化剂用量、带水剂加入量、反应时间等因素对己二酸二异辛酯酯化率的影响。实验结果表明,N-甲基吡咯烷酮硫酸氢盐对合成己二酸二异辛酯有着良好的催化活性,当己二酸用量为0.1mol时,醇酸摩尔比为2.6:1,催化剂用量为己二酸物质的量的1.2%,带水剂环己烷为10mL,回流温度下反应时间120min,在此条件下,反应的酯化率可达99%以上,且催化剂重复使用6次仍保持较高活性。     

对甲苯磺酸铜催化合成乙酸环己酯

研究了对甲苯磺酸铜催化乙酸与环己醇的酯化反应,考察了物料配比、催化剂用量、反应时间和带水剂用量等因素对酯化率的影响。实验结果表明,反应的优化条件是乙酸用量为0·2mol,n(环己醇)∶n(乙酸)=1·4,甲苯磺酸铜用量为1·2g,带水剂环己烷为15mL,回流反应60min后酯化率可达96·7%,催化剂重复使用7次仍可保持较高活性。     

二苯胺甲烷磺酸盐催化合成乙酸环己酯

以二苯胺甲烷磺酸盐为催化剂，对乙酸与环己醇间的酯化反应进行了研究。考察了反应时间、催化剂用量、醇酸摩尔比和带水剂用量等对乙酸环己酯收率的影响。结果表明反应的较佳条件：当乙酸用量为0．1mol时，醇酸摩尔比为1．3，二苯胺甲烷磺酸盐用量为0．5g（约2mmol），带水剂环己烷用量8mL，反应30mi。后酯收率达96．4％，催化剂重复使用5次仍保持较高活性。产品经折射率、IR光谱进行了表征。     

微波辐射对甲苯磺酸催化合成乙酸环己酯

以冰醋酸和环己醇为原料 ,环已烷为带水剂 ,对甲苯磺酸作催化剂 ,采用微波辐射技术 ,在常压下直接合成乙酸环己酯。最适宜反应条件为 :n(环己醇 )∶n(乙酸 ) =1 5∶1 0 ,对甲苯磺酸用量 0 2 0 g ,带水剂用量 5mL ,微波功率 5 95W ,辐射时间 15min ,产率达 97%以上     

离子液体掺杂聚苯胺催化合成水杨酸异戊酯

以聚苯胺PAn和自制离子液体[Hnmp]HSO4为原料,制备了[Hnmp]HSO4掺杂率为14.2%(质量分数)的催化剂PAn-[Hnmp]HSO4。以PAn-[Hnmp]HSO4为催化剂,水杨酸和异戊醇为原料合成了水杨酸异戊酯,考察了PAn-[Hnmp]HSO4的催化活性,通过正交试验探讨各因素对反应的影响。结果表明,在n(水杨酸)∶n(异戊醇)=1∶6,催化剂用量为反应物料总质量的6%,回流反应时间为3 h,带水剂环己烷用量为反应物总质量40%的较佳条件下,产品收率达93.52%,纯度经气相色谱分析大于99.0%。催化剂重复使用7次后,产品收率仍大于90.0%。     

活性炭固载酸性催化剂合成丙酸环己酯

以丙酸和环己醇为原料,采用颗粒状活性炭固载对甲苯磺酸作催化剂合成丙酸环己酯。考察影响反应的因素,实验结果表明,酯化反应的最佳条件:n(丙酸)∶n(环己醇)=1.3∶1,催化剂用量1.4 g,反应时间60 min,带水剂环己烷10 mL,酯收率可达93.58%。     

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。