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1.
二甲基二烯丙基氯化铵共聚季铵盐的合成及性能研究   总被引:2,自引:0,他引:2  
以氯丙烯为原料 ,季铵化一步法合成二甲基二丙烯基氯化铵 (DMDAAC)后再与丙烯酸、丙烯酰胺共聚 ,制得阳离子型聚季铵盐 (PDMDAAC)。DMDAAC较佳合成条件为 :氯丙烯∶二甲胺∶氢氧化钠 =2 2 0∶1 0 0∶1 0 0 (mol) ,滴加温度 10~ 30℃ ,滴加时间 3h ,恒温时间4h ,收率为 94 % ;PDMDAAC/AA/AM的共聚条件为 :DMDAAC∶AA +AM =1∶2 .6(mol) ,AA∶AM =1∶3.5 (mol) ,滴加温度 60℃ ,滴加时间 3h ,恒温时间 3 5h。研究探讨了反应影响因素 ,确定了工艺条件 ,并在洗发香波中进行了应用试验  相似文献   

2.
以γ-氯丙烯和甲基二氯硅烷为原料,氯铂酸为催化剂合成γ-氯丙基甲基二氯硅烷。通过正交实验法和单因素法探索了温度控制、催化剂用量、原料配比、反应时间等因素对γ-氯丙基甲基二氯硅烷收率的影响。结果表明:在反应温度100℃,n(氯铂酸)∶n(甲基二氯硅烷)=1∶20000,n(甲基二氯硅烷)∶n(氯丙烯)=1∶0.9的工艺条件下,单独使用氯铂酸的异丙醇溶液为催化剂,2h之内γ-氯丙基甲基二氯硅烷的收率达到50%以上。  相似文献   

3.
曾嵘  刘冬  周宝强  高瑞昶 《化工进展》2014,33(12):3364-3367
以二乙二醇、氯丙烯、氢氧化钠为原料,四丁基氯化铵为相转移催化剂,不引入其他溶剂,经Williamson成醚法合成了二乙二醇单烯丙基醚[2-(2-烯丙氧基乙氧基)-乙醇]。用红外吸收光谱和1H核磁共振谱对二乙二醇单烯丙基醚进行了表征。研究了反应时间、反应温度、原料摩尔比、碱用量、催化剂用量对目标产物收率的影响,得到较优的操作条件为:反应时间3h、反应温度80℃、n(二乙二醇)∶n(氢氧化钠)∶n(氯丙烯)=6∶1.2∶1、催化剂用量为氯丙烯质量的5%。在此条件下,收率达86.7%,纯度为99.2%。  相似文献   

4.
喹啉酸的合成研究   总被引:1,自引:0,他引:1  
以喹啉为起始原料,经过氧化、碱解、酸化合成医药中间体喹啉酸,详细考察了氧化反应时间,加料方式,催化剂用量对反应的影响,获得了喹啉酸合成优惠反应条件:n(喹啉)∶n(氯酸钠)∶n(五水硫酸铜)∶n(硫酸)∶n(催化剂)=1∶5∶1.3∶4∶0.0005,氯酸钠滴加温度97 ̄103℃,滴加氯酸钠时间20h。用此法合成喹啉酸,产品总收率74.5%,产品纯度98.2%。  相似文献   

5.
以杂多酸为催化剂 ,2 ,6 二异丙基酚 (DIPP)与异戊二烯 (IP)经环烷基化反应合成麝香DDHI。研究了催化剂种类和用量、原料配比、反应温度及时间对反应结果的影响。反应最佳条件为∶催化剂为磷钨酸固载于活性炭上 ,n(DIPP)∶n(IP) =2 .0 ,m(C1)∶m(IP) =0 .8~ 0 .9,反应温度 36℃~ 4 2℃ ,滴加时间 2h ,保温时间 1h ,产品收率 83.7%。  相似文献   

6.
催化氧化法合成硫化促进剂CZ的绿色工艺   总被引:3,自引:1,他引:3  
研究了用双氧水作氧化剂合成硫化促进剂CZ的方法,探索了催化剂、原料配比、反应时间、反应温度等对反应的影响,确定了最佳工艺条件为n(M)∶n(环己胺)∶n(双氧水)=1.0∶2.4∶2.0,反应温度为40~50℃,反应时间为(1+1)h(滴加时间+保温时间),CZ收率达95%以上,初熔点达98℃(一级品)。采用3 000 L的氧化釜进行了中试,经过多批次生产,得到的产品均为一级品,收率稳定在95%~96%。  相似文献   

7.
三(环氧丙基)异氰尿酸酯的合成   总被引:2,自引:0,他引:2  
采用2步法合成了三(环氧丙基)异氰尿酸酯(TGIC),研究了物料配比、催化剂、反应时间、反应温度、反应时真空度等对产率的影响,得到了如下工艺条件:采用四甲基氯化铵作催化剂,原料配比为:n(氰尿酸)∶n(环氧氯丙烷)=1∶18;第1步反应时间为6h;第2步反应时间为1 5h;第1步反应温度90℃;第2步反应真空度0 09MPa,产率95%以上。  相似文献   

8.
田立颖  杜杨  吉法祥  魏焕曹 《精细化工》2000,21(10):569-569
用二步法合成了季铵盐阳离子单体N ,N 二甲基二烯丙基氯化铵 (DMDAAC)。第一步 ,向反应瓶中加入 1mol二甲胺的水溶液 ,控制温度 40℃以下 ,滴加 1mol氯丙烯和 1molNaOH水溶液 (其质量分数为 40 % )。滴加完后再反应 2h,分取上层有机相 ;第二步 ,将有机相加入反应瓶中 ,同时加入适量的丙酮 ,控制温度在 30℃以下 ,滴加 1mol氯丙烯 ,反应 4h。过滤、洗涤、干燥得阳离子单体DMDAAC ,总转化率为 63%。以n(DMDAAC)∶n(丙烯酸胺 ) =1∶3在水溶液中共聚 ,合成了阳离子共聚物 [P(DMDAAC AM) ]。反应以分别占单体总质量的 0 5 %的过硫酸钾和亚硫酸氢钠为引发剂 ,反应温度 40℃ ,反应时间 6~ 8h。并利用IR、1HNMR对单体和共聚物进行了结构表征。  相似文献   

9.
以对甲基苯磺酸为催化剂,甲基丙烯酸(MA)和氯乙醇为原料合成甲基丙烯酸氯乙酯。以环己烷为带水剂、对苯二酚为阻聚剂,考察了催化剂用量、醇酸物质的量比、反应时间、反应温度对收率的影响。优化了合成工艺,结果表明,甲基丙烯酸氯乙酯合成的优化条件为:n(氯乙醇)∶n(甲基丙烯酸)=1.4∶1、催化剂加量为2%(以反应物总质量计)、反应时间为6 h、反应温度为90℃,收率可达90%以上。  相似文献   

10.
对1,2-二苯氧基乙烷的合成工艺进行研究,以1,2-二氯乙烷、苯酚为原料,聚乙二醇为催化剂合成1,2-二苯基乙烷;考查反应温度、反应时间、反应配比、催化剂用量对反应的影响,并确定了较佳的工艺条件为:物料配比为n苯酚∶n氢氧化钠∶n二氯乙烷=1∶1∶0.55,催化剂用量为苯酚用量的5%(w%w),先在70℃下滴加二氯乙烷,滴加时间为4h,后升温至90℃,压力为4Mpa下保温反应8h,得到粗品经乙醇精制得到纯度为99%的1,2-二苯氧基乙烷,收率高达85%.  相似文献   

11.
12.
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   

13.
14.
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.  相似文献   

15.
16.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
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。  相似文献   

17.
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   

18.
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   

19.
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   

20.
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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