苯乙酮-甲醛树脂的合成研究

以苯乙酮和甲醛为原料,氢氧化钠为催化剂合成苯乙酮-甲醛树脂,考察催化剂用量、醛酮摩尔比、反应时间等对树脂软化点和羟值的影响,借助Fr—IR及1H—NMR对聚合产物进行了表征。发现在醛酮摩尔比为1．0、氢氧化钠用量为3．0％（质量）、反应时间为7h时,可获得软化点为80．0℃,羟值为23．3mgKOH／g的苯乙酮-甲醛树脂。树脂的FT-IR和^1H—NMR图谱表明苯乙酮甲基上的α—H与甲醛发生缩聚反应。     

3-氯甲基-4-羟基苯乙酮合成工艺研究

利用盐酸作催化剂 ,由对羟基苯乙酮和甲醛经缩合生成 3 氯甲基 4 羟基苯乙酮 ,研究了该中间体合成的配料比、反应温度和反应时间对反应收率的影响。结果表明 :对羟基苯乙酮、甲醛、盐酸配料摩尔比为 1∶2∶5 ,反应温度为 30～ 35℃ ,反应时间为 3 .0h ,反应收率为 80 % ,纯度符合药用标准     

苯酚-尿素-甲醛三元共缩聚树脂合成工艺的研究

针对脲醛树脂在制板过程以及人造板材在使用过程中不断释放甲醛。危害人体健康的环保问题,以及耐水、耐老化性能差的缺点。以苯酚、尿素和甲醛为原料,采用高温（90℃）缩聚反应合成苯酚-尿素-甲醛共缩聚树脂（PUF胶黏剂）,缩短了反应时间,提高了耐水、耐老化性能,且游离甲醛含量〈O．3％,游离苯酚含量〈0．5％。对树脂的结构和性能进行全面的分析,得出当甲醛、尿素、苯酚摩尔比为10：8：1时树脂性能最佳,压制的胶合板力学性能好,板材甲醛释放量达到GB18580—2001中E2级水平。     

水溶性环己酮-三聚氰胺-甲醛共缩聚树脂的合成与表征

以环己酮、三聚氰胺、甲醛为原料,氢氧化钠为催化剂,用"两步法"合成出环己酮-三聚氰胺-甲醛树脂(CMFR),考察了三聚氰胺用量、醛酮物质的量比、催化剂用量及反应时间等对CMFR的游离甲醛含量及溶水倍数的影响,并借助FT-IR、13C-NMR、DSC、TG等对CMFR进行了表征。发现在环己酮、三聚氰胺、甲醛物质的量比为1.0∶0.2∶2.0,催化剂用量为0.6%,反应时间为120min,反应温度为90℃的条件下,合成出的CMFR游离甲醛含量为0.45%,溶水倍数为8.2。FT-IR和13C-NMR结果表明CMFR分子中存在三聚氰胺结构;DSC分析表明CMFR仅存在一个固化放热峰,说明三聚氰胺参与了树脂的共缩聚反应,形成了均一的分子结构,其固化温度约为182.5℃,固化后CMFR的耐溶剂性能提高。     

3—氯甲基—4—羟基苯乙酮合成工艺研究

利用盐酸作催化剂,由对羟基苯乙酮和甲醛经缩合生成3－氯甲基－4－羟基苯乙酮,研究了该中间体合成的配料比、反应温度和反应时间对反应收率的影响。结果表明：对羟基苯乙酮、甲醛、盐酸配料摩尔比为1;2：5,反应温度为30－35℃,反应时间为3．0h,反应收率为80％,纯度符合药用标准。     

环己酮-甲醛树脂

环己酮-甲醛树脂综合性能良好,是一种新型涂料添加剂。其生产方法有三种:甲基环己酮与甲醛共缩合;环己酮与甲醛在有机溶剂和氢氧化钠存在下一步共缩合;环己酮与甲醛在碱性条件下两步合成。工业上采用第三种方法。     

环已酮-甲醛树脂

环己酮-甲醛树脂综合性能良好,是一种新型涂料添加剂.其生产方法有三种:甲基环己酮与甲醛共缩合;环己酮与甲醛在有机溶剂和氢氧化钠存在下一步共缩合;环己酮与甲醛在碱性条件下两步合成.工业上采用第三种方法.     

2,2-二羟甲基十二酸的合成

研究了以月桂醛(正十二醛)、甲醛、过氧化氢为原料,经羟醛缩合、过氧化氢氧化合成2,2-二羟甲基十二酸的方法,探讨了原料摩尔比、催化剂或氧化剂用量、反应温度和时间对羟醛缩合反应和氧化反应的影响。结果表明,月桂醛(正十二醛)与甲醛摩尔比为2.6∶1.0、催化剂与月桂醛摩尔比为0.51∶1.0、羟醛缩合反应温度为50℃、反应时间为3 h,合成的2,2二-羟甲基十二醛收率为46%;H2O2与2,2二-羟甲基十二醛摩尔比为1.1∶1.0,氧化反应温度为70℃、反应时间为7 h,合成的2,2二-羟甲基十二酸收率为86%。并用13C和1H核磁共振谱表征了2,2-二羟甲基十二酸的结构。     

4-氨基乙酸苯乙酮的合成研究

以摩尔比为1.0:1.2的4-氨基苯乙酮和氯乙酸为原料,在4 mol·L~(-1)碳酸钠溶液中,反应6h,合成4-氨基已酸苯乙酮,反应温度为90℃,收率可达86％。若采用超声催化合成,反应时间缩短至3h,产率达89.1％。用IR对目标产物进行了结构表征。     

苯乙酮1，2-丙二醇缩酮的合成研究

以强酸性阳离子交换树脂为催化剂,通过苯乙酮和1,2-丙二醇反应合成苯乙酮1,2-丙二醇缩酮,系统的研究了酮醇物质的量之比、催化剂用量和反应时间等因素对产品收率的影响。结果表明：在酮醇物质的量比为1：2,催化剂用量为反应物总质量的0．6％,环己烷为带水剂,反应时间3h的优化条件下,产率达79．8％。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

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.     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.