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1.
以三氯化磷和双酚A为原料合成了抗氧剂亚磷酸三双酚A酯.探索了反应溶剂、三氯化磷滴加时间、滴加温度及物料配比等反应条件对产率的影响.结果表明:反应溶剂为乙醚,三氯化磷滴加时间为20 min,滴加温度为25℃,物料配比[n(双酚A)∶n(三氯化磷)]为3.00∶1.05.在最适宜工艺条件下所制得的产品为白色固体,熔点为64...  相似文献   

2.
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   

3.
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   

4.
二亚磷酸二(苯甲醇)季戊四醇酯的合成   总被引:3,自引:0,他引:3  
以亚磷酸三乙酯、季戊四醇、苯甲醇为原料,二丁基氧化锡为催化剂,采用酯交换法合成了二亚磷酸二(苯甲醇)季戊四醇酯.探讨了反应温度、反应时间、催化剂、催化剂用量、物料配比等因素的影响,确定了最佳工艺条件:第一步的反应温度为130~140℃、反应时间为2 h,第二步的反应温度为170~180℃、反应时间为1.5 h,有机锡为催化剂、其用量为1.1 g,物料配比n(季戊四醇)∶n(亚磷酸三乙酯)∶n(苯甲醇)为1∶2.00∶2.00,此时产品的收率在95%以上,在20℃下折射率为1.5515.并通过元素分析及红外分析对产品进行了表征.  相似文献   

5.
以季戊四醇、亚磷酸三乙酯和2,4-二叔丁基苯酚为原料,合成了双(2,4一二叔丁基苯基)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、亚磷酸三乙酯和季戊四醇的摩尔比为2.04∶2.20∶1.00,催化剂有机锡的用量为反应物总量的2.0%,反应温度在140~150℃范围内,反应时间为7小时。  相似文献   

6.
二硫化二苯并噻唑的催化合成   总被引:1,自引:0,他引:1  
杨晓玲 《应用化工》2011,40(1):88-90
以2-巯基苯并噻唑和氨水为原料,双氧水作氧化剂,经催化剂A进行催化,合成了二硫化二苯并噻唑。通过考察催化剂种类、催化剂用量、氨水用量、物料配比、反应时间和反应温度对产率的影响,得出适宜的工艺条件为:选用催化剂A,用量为2-巯基苯并噻唑的1%,氨的加入量为n(2-巯基苯并噻唑)∶n(氨水)=1∶6.0,双氧水用量为n(2-巯基苯并噻唑)∶n(双氧水)=2∶1.2,反应时间3 h,反应温度50℃。在此条件下,二硫化二苯并噻唑的产率为90.7%,熔点为165.3~168.7℃。二硫化二苯并噻唑粗品通过甲苯进行一次重结晶后,熔点可达173.6~175℃。  相似文献   

7.
首次以2-巯基苯并噻唑为原料,发烟硝酸作氧化剂,冰醋酸为反应溶剂一步合成二硫化二苯并噻唑。通过考察温度、物料配比、反应时间和氧化剂的用量,得出适宜的工艺条件为温度20℃、n(M)∶n(冰醋酸)为1∶20、反应时间40 min、n(发烟硝酸)∶n(促进剂M)为2∶1,在此条件下,二硫化二苯并噻唑的产率可以达到92.4%,熔点为169.6~171.0℃。  相似文献   

8.
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   

9.
研究了用三氯化磷和丙醇合成亚磷酸二丙酯的方法。讨论了物料配比、温度、反应时间、溶剂用量等因素对反应的影响。确定了合成亚磷酸二丙酯的最佳反应条件,在选择的试验条件下产率为85.4%。  相似文献   

10.
以乙醇水溶液为反应介质,采用环境友好型氧化剂H2O2,将2-巯基苯并噻唑(促进剂M)一步氧化制备高品质医药级二硫代二苯并噻唑(促进剂DM)。考察了反应温度、加料时间、反应时间、溶剂用量、物料配比等因素对反应结果的影响,得到的较佳工艺条件为反应温度35℃,加料时间3h,反应时间3h,V(溶剂)∶m(M)=3.5mL/g,n(M)∶n(H2O2)=2∶1.3。在上述条件下,DM的熔点可达182℃,纯度高达98%,产率高达98%。  相似文献   

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12.
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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14.
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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17.
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   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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