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亚磷酸酯类抗氧剂626的合成与表征 总被引:4,自引:0,他引:4
以季戊四醇、三氯化磷和2,4-二叔丁基苯酚为原料,在实验室合成了双(2,4-二叔丁基苯基)季戊四醇二亚磷酸酯。采用正交试验考察了反应温度、反应时间、催化剂及物料配比对产品收率的影响。试验结果表明,整个工艺过程适宜的工艺条件为:2,4-二叔丁基苯酚、三氯化磷和季戊四醇的摩尔比为2.00∶2.05∶1.00,催化剂B的用量为季戊四醇质量的2.2%,第一步反应温度为130℃,时间为2.5 h;第二步反应温度为120℃,时间3.0 h。产品元素分析及红外光谱与目的产物相一致。 相似文献
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以2,4-二枯基酚、季戊四醇、三氯化磷为基本原料合成了抗氧剂852,即二(2,4-二枯基苯基)季戊四醇双亚磷酸酯。重点讨论了反应溶剂、催化剂、物料配比、反应温度、反应时间和结晶溶剂对产品收率的影响,筛选出了最佳的合成工艺条件为:物料摩尔配比η(2,4-二枯基酚)∶η(三氯化磷)∶η(季戊四醇)为2.00∶2.18∶1.00,第一步反应温度60℃,反应4h,第二步反应110℃,反应6h,反应收率为78%。 相似文献
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抗氧剂二硬脂基季戊四醇二亚磷酸酯的合成新工艺 总被引:1,自引:0,他引:1
本文以季戊四醇、亚磷酸三乙酯和十八醇为原料,在实验室合成了二硬脂基季戊四醇二亚磷酸酯。考查了反应温度、反应时间、催化剂及物料配比对产品收率的影响.实验结果表明,整个工艺过程可分为两步:合成季戊四醇二亚磷酸酯中间体时,最佳的工艺条件为:亚磷酸三乙酯、季戊四醇的摩尔比为2.05:1,催化剂的用量为季戊四醇量的3%,反应温度为13℃,时间为2.5h;在二硬脂基季戊四醇二亚磷酸酯的合成时,十八醇与中间体季戊四醇二亚磷酸酯的摩尔比为2.05:1,反应温度为16℃,时间3h。合成的产品中无酚无三废产生,产品元素分析及红外光谱与目的产物相一致。 相似文献
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以季戊四醇、亚磷酸三乙酯和十六醇为原料,合成了双十六烷基季戊四醇二亚磷酸酯。考察了反应温度、反应时闻、催化荆及物料配比对产品收率的影响。实验结果表明,整个工艺过程可分为两步,合成季戊四醇二亚磷酸酯中间体时,最佳的工艺条件为:亚磷酸三乙酯、季戊四醇的摩尔比为2.05:1,催化剂的用量为季戊四醇质量的3%,反应温度为130℃,时间为2.5h;在合成双十六烷基季戊四醇二亚磷酸酯时,十六醇与中间体季戊四醇二亚磷酸酯的摩尔比为2.05:1,反应温度为160℃,时间2.5h。合成的产品中无酚无三废产生,产品元素分析及红外光谱与目的产物相一致。 相似文献
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以季戊四醇、亚磷酸三乙酯和十八醇为原料,在实验室合成了二硬脂基季戊四醇二亚磷酸酯。考察了反应温度、反应时间、催化剂及物料配比对产品收率的影响。试验结果表明,合成工艺过程可分为两步:合成季戊四醇二亚磷酸酯中间体时,适宜的工艺条件为:亚磷酸三乙酯、季戊四醇的摩尔比为2.05,催化剂的用量为季戊四醇质量的3%,反应温度为130℃,时间为2.5 h;在二硬脂基季戊四醇二亚磷酸酯的合成时,十八醇与中间体季戊四醇二亚磷酸酯的摩尔比为2.05,反应温度为160℃,时间3 h。产品使用结果表明,该产品能够与钙锌稳定剂组分协同并用抑制PVC初期着色;在PP制品中,与酚类抗氧剂1010存在明显的协同作用,显示出良好的长期热氧稳定性。 相似文献
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本文以季戊四醇、亚磷酸三乙酯和十八醇为原料,在实验室合成了二硬酯基季戊四醇二亚磷酸酯。考查了反应温度、反应时间、催化剂及物料配比对产品收率的影响。实验结果表明,整个工艺过程可分为两步:合成季戊四醇二亚磷酸酯中间体时,最佳的工艺条件为:亚磷酸三乙酯、季戊四醇的摩尔比为2.05∶1,催化剂的用量为季戊四醇量的3%,反应温度为130℃,时间为2.5h;在二硬脂基季戊四醇二亚磷酸酯的合成时,十八醇与中间体季戊四醇二亚磷酸酯的摩尔比为2.05∶1,反应温度为160℃,时间3h。合成的产品中无酚无三废产生,产品元素分析及红外光谱与目的产物相一致。 相似文献
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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. 相似文献
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Cheng-Le Zhao Shane Porzio Alan Smith Haiyan Ge H. T. Davis L. E. Scriven 《Journal of Coatings Technology and Research》2006,3(2):109-115
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. 相似文献
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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 总被引:15,自引:0,他引:15
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。 相似文献
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M. S. J. Simmonds W. M. Blaney F. Delle Monache M. Marquina Mac-Quhae G. B. Marini Bettolo 《Journal of chemical ecology》1985,11(12):1593-1599
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. 相似文献
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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. 相似文献
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以大分子引发剂氯乙酰化聚苯乙烯微球(PS-acyl-Cl)经原子转移自由基聚合(ATRP)法引发丙烯酰胺(AM)和甲基丙烯酸缩水甘油酯(GMA)单体的共聚接枝,制得一种触角状亲水性环氧载体(PS-acyl-g-P(AM-co-GMA)),再经二乙醇胺(DEA)的环氧基开环胺化反应,得到一种含多个-NCH2CH2OH螯合配基的多齿-五元螯合环的触角状亲水性羟胺树脂(PS-acyl-g-P(AM-co-GMA)-DEA)。将此树脂用于硼吸附研究,结果表明,PS-acyl-g-P(AM-co-GMA)-DEA树脂对硼的吸附满足Langmuir方程,为单分子层吸附;饱和吸附量约为37.7 mg·g-1,且树脂5 min即可达到吸附平衡,与其它已报道的吸硼树脂相比,该树脂具有更高的吸附量和吸硼速率。吸附动力学研究表明,树脂吸附硼的过程主要由颗粒扩散过程控制。重复使用5次后该树脂的吸附量基本不变,解吸率均在90%以上,重复使用性能良好。 相似文献