非离子复合型水性环氧固化剂合成及性能研究

以四乙烯五胺(TEPA)作为反应底物,与低相对分子质量的环氧树脂(DER331)和聚乙二醇二缩水甘油醚(PGGE)混合树脂反应,再用单环氧封端剂苯基缩水甘油醚(PGE)和十二至十四烷基缩水甘油醚(AGE)作为复合封端剂进行封端,合成非离子复合型水性环氧固化剂。探究了最佳合成条件,采用红外光谱(FT-IR)对合成的产物进行结构表征,并考察了与水性环氧乳液固化后的涂膜性能。结果表明:最佳合成条件为物料比n(伯胺基)∶n(环氧基)=2.3∶1、初始反应温度65℃、反应时间3 h、复合封端剂的比例n(AGE)∶n(PGE)=3∶7。合成的水性环氧固化剂与水性环氧乳液固化形成的漆膜耐腐蚀性能优越。     

新型非离子型水性环氧固化剂的合成及性能研究

为提高水性环氧涂料的固化性能和适用期,以自制聚酰胺和生物基戊二胺为起始原料,聚乙二醇二缩水甘油醚（ PEGGE）为亲水链段,双酚 A型环氧树脂（ E-51）为疏水链段,邻甲苯缩水甘油醚（ CGE）为封端剂制备了非离子型低温水性环氧固化剂,并与自制水性环氧乳液复配制得双组分水性环氧涂料。考察了环氧固化剂合成工艺参数及涂膜各项性能。结果表明：该固化剂含有较长的柔性脂肪烃碳链和聚醚链段能够提高涂膜的柔韧性;双酚 A型环氧树脂参与扩链反应能够解决与乳液不兼容等问题;苯环结构增加了涂膜的硬度;涂膜室温固化后性能优异,具有良好的物理机械性能、耐水性、耐酸碱性和耐盐雾性。     

水性环氧树脂防腐清漆的制备与性能

以自制非离子水性环氧固化剂与环氧树脂混合制备水性环氧树脂防腐清漆,探讨了封端剂种类、水性环氧固化剂与环氧树脂配比、固化温度对漆膜性能的影响,结果表明最佳封端剂为苯基缩水甘油醚(PEG);最佳水性环氧固化剂与环氧树脂配比为环氧/胺氢当量比为1.1;漆膜室温下即可固化,防腐性能优秀。     

核电站用水性环氧涂料的研制

介绍了核电站用水性环氧涂料的配方、合成工艺及性能指标。讨论了水性胺环氧加成物固化剂、颜填料及助剂对涂料性能的影响。所配制的水性环氧涂料与溶剂型环氧涂料性能相当，并达到了核电站专用涂料的性能要求。     

水性含磷环氧固化剂

采用环氧树脂与二乙烯三胺反应生成端胺基环氧-胺加成物，再经氯磷酸二苯酯（DPCP）与单环氧化合物封端和成盐，合成了一系列不同磷含量的新型水性环氧自乳化固化剂。研究了磷含量对固化剂的乳化性能以及对漆膜的表观性能和热性能等的影响。当封端剂中氯磷酸二苯酯的含量达到75％时，所得自乳化固化剂具有较好的乳化效果，由其制备的漆膜综合性能较好，且漆膜在600℃时的焦炭残余量比不含磷的树脂提高了近1倍，达到18．04％。     

水性环氧树脂涂料及其固化机理的研究

通过对环氧树脂室温固化剂三乙烯四胺进行封端、加成、成盐等一系列改性,制得自乳化水性环氧树脂固化剂;与低相对分子质量的液体环氧树脂混合后,获得了水性环氧树脂涂料。研究了不同封端剂对固化剂乳化性能的影响以及与环氧树脂配成涂料后对涂膜性能的影响,并通过对固化成膜过程的观察,阐述了水性环氧体系固化机理。获得的涂料乳液粒径小于2μm;涂膜硬度>0.7;附着力1级;涂膜具有良好的透明性、耐水性及耐化学药品性。     

自乳化水性环氧固化剂的合成及性能

采用单环氧化合物(AGE)为封端剂,环氧树脂(E44)为扩链剂,以三乙烯四胺(TETA)为原料,合成了一种具有自乳化效果的水性环氧固化剂。采用傅里叶变换红外光谱(FT-IR)对合成的水性环氧固化剂结构进行了表征,研究了合成条件对该水性固化剂成膜性质的影响。红外测试结果显示:环氧基团特征峰消失,环氧基全部参与了反应;涂膜性能测试表明:n(AGE)∶n(E44)∶n(TETA)=4.5∶1.0∶3.0时,醋酸成盐率为10%,所得涂膜外观、耐盐雾性能最佳。     

水性环氧固化剂的制备及其涂膜性能研究

采用丙烯酸丁酯改性三乙烯四胺(TETA),以环氧树脂E-51为封端剂,制备水性环氧固化剂。研究表明:在反应温度为70℃、反应时间为3 h、n(三乙烯四胺加成物)∶n(环氧树脂)为2∶1时,制备的水性环氧固化剂性能优良,与环氧乳液配制的涂料的涂膜具有硬度高,附着力好、流平性好、光泽高等优点。     

非离子型水性环氧树脂固化剂的合成与性能研究

采用低相对分子质量的环氧树脂E-51与聚醚-4000反应制备环氧改性聚醚加成物,再与多乙烯多胺进行反应制备胺封端的聚醚-环氧-胺加成物,最后采用单环氧化合物进行封端,合成非离子型水性环氧固化剂,实验表明工艺可行。对环氧E-51改性聚醚-4000合成过程中的各影响因素进行了研究,并对非离子型水性环氧固化剂的固化性能进行了评价。最佳配方与工艺为:n(环氧树脂E-51)∶n(聚醚-4000)2∶1,催化剂选用含三氟化硼(BF3)质量分数2%的乙醚溶液(60℃时加入,加入量为2%)。与现有的市售水性环氧固化剂固化性能相比,非离子型水性环氧固化剂固化的环氧体系的柔韧性和耐冲击性有大幅提高。     

基于 1，3-环己二甲胺水性环氧固化剂的合成与性能

以 1,3-环己二甲胺（ 1,3-BAC）和三乙烯四胺（ TETA）作为基础胺,聚乙二醇二缩水甘油醚（PEGDGE）、环氧树脂（E51）为扩链剂,正丁基缩水甘油醚（BGE）为封端剂,合成 1,3-BAC水性环氧固化剂。探讨了最佳的反应条件,采用红外光谱（ FT-IR）、差示扫描量热仪（ DSC）对水性环氧固化剂进行了分析与表征,并考察了水性环氧固化剂的固化性能。结果表明：合成了 1,3-BAC水性环氧固化剂; DSC表明水性环氧固化剂与环氧树脂 E51固化时,其表观活化能 △E低于 60 kJ/mol,具有室温固化特性。在活泼氢与环氧基物质的量比为 1. 1∶1时,固化 7d后涂膜硬度 2H,附着力 1级,柔韧性 1 mm,室温浸水 240 h漆膜表观完好,耐酸碱性优异。     

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.     

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。     

ICP-MS法测定地球化学样品中As、Cr、Ge、V等18种微量痕量元素的研究

建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。     

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.