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1.
由硫酸铝催化合成环氧大豆油   总被引:7,自引:0,他引:7  
以硫酸铝作催化剂催化合成环氧大豆油方法可行,反应活性高,比硫酸催化法后处理容易,比阳离子交换树脂催化法成本低。实验投料比为大豆油:双氧水:甲酸:硫酸铝=1:0.27~0.29:0.12~0.15:0.1~0.08,过氧甲酸环氧化温度35℃,环氧化收率96%,环氧大豆油产品环氧值6.17~6.20%,酸值0.44~0.48mgKOH/g。  相似文献   

2.
无酸法合成环氧大豆油的研究   总被引:2,自引:0,他引:2  
李坤兰  高爽  奚祖威 《化学世界》2008,49(5):293-296
以(-πC5H5NC16H33)3[PO4(WO3)4]作为催化剂,1,2-二氯乙烷为溶剂,H2O2(30%,质量分数)为氧源,在无酸环境下直接合成环氧大豆油,并利用正交实验的方法对大豆油环氧化反应的工艺条件进行优化,得出了最佳反应条件为:n(H2O2)∶n(大豆油双键)=1.25∶1,m(二氯乙烷)∶m(大豆油)=3.5∶1,反应温度70°C,反应时间4 h,产品环氧大豆油的环氧值大于6.2%,碘值小于2.60 gI/100 g,达到一级品要求。催化剂循环使用三次催化活性保持不变。  相似文献   

3.
何亚三  林仁扎 《应用化工》2012,41(7):1201-1203,1207
制备了含铝5%的负载型Al/SiO2多相催化剂,以其为催化剂,采用改进型无溶剂法工艺合成环氧大豆油。优化工艺条件为:反应时间4 h,大豆油∶甲酸(85%)∶H2O2(30%)=1∶0.2∶0.92(体积比),催化剂用量为2.0 g,反应温度40~60℃,所得产品色泽浅,环氧值高(>6.5%),产品质量优于国家标准,催化剂可重复使用,再生容易,无腐蚀,对环境友好。  相似文献   

4.
文章采用732#强酸性阳离子交换树脂为催化剂,改进型无溶剂法合成高品质环氧大豆油。实验确定了高品质环氧大豆油的最佳合成条件:采用逐步加料,按m(大豆油):m(88%甲酸):m(30%双氧水):m(催化剂)=1:0.35:1.2:0.15的比例加料,加0.5 mL 1%的EDTA稳定剂,制得的环氧大豆油品质较高。  相似文献   

5.
以非酸催化剂为催化剂,采用无溶剂法工艺合成环氧大豆油,进行实验室小试,优化工艺条件为:大豆油∶H2O2∶乙酸为1∶(0.40~0.45)∶(0.65~0.70)(W/W/W),催化剂用量5%~6%(以大豆油计),相转移稳定剂用量0.2%~0.3%(以大豆油计),反应温度70~75℃。根据小试优化的工艺条件确定了环氧大豆油的生产工艺,分别采用新鲜乙酸和乙酰柠檬酸三丁酯回收乙酸进行了中试,所得产品质量能达到一级品和合格品要求。  相似文献   

6.
环氧大豆油合成实验研究   总被引:1,自引:0,他引:1  
王燕石 《河北化工》2008,31(2):37-38
介绍了无溶剂法合成环氧大豆油的原理和生产方法,并通过实验确定了最佳工艺条件:反应温度为60~65 ℃,大豆油∶双氧水∶甲酸为250 mL∶120 mL(31%)∶25 mL(88%),催化剂浓硫酸用量为0.15 mL.  相似文献   

7.
微量硫酸催化环氧大豆油的合成   总被引:1,自引:0,他引:1  
在无溶剂条件下,以甲酸为载氧体合成了环氧大豆油. 通过正交实验确定了甲酸自催化合成环氧大豆油的优化工艺条件. 为进一步提高环氧值和缩短反应时间,添加微量硫酸作为催化剂,并优化了其用量. 结果表明,当大豆油、88%甲酸、30%双氧水和硫酸的质量比为1:0.13:0.7:0.004时,在65℃下反应3 h,产品的环氧值为6.2%,残留碘值<6.0%. 采用红外光谱和核磁共振对产品进行了表征.  相似文献   

8.
由苯甲酸钠和氯化苄通过相转移催化法合成了苯甲酸苄酯,考察了几种季铵盐类相转移催化剂的亲核取代反应性能.结果表明,季铵盐类相转移催化剂四丁基碘化铵[(C4H9)4NI]对合成苯甲酸苄酯的催化性能较好,在n(苯甲酸钠)∶n(氯化苄)为1∶1.3、反应温度为110℃、反应时间为2.5~3.0 h、催化剂用量为苯甲酸钠摩尔量的6%、体系pH值为5~6时,苯甲酸苄酯的产率超过了90%.  相似文献   

9.
相转移催化大豆油醇解研究   总被引:1,自引:1,他引:0  
通过催化大豆油与甲醇进行酯交换反应合成脂肪酸甲酯(FAME),研究了相转移催化剂对油脂醇解的催化性能。考察了不同醇油摩尔比、催化剂用量、反应时间和反应温度对大豆油醇解反应的影响,得到了较佳工艺条件:n(甲醇)∶n(大豆油)为6∶1,催化剂用量为大豆油质量的1.0%,35℃~40℃下反应1 h。结果表明:苄基三乙基氢氧化铵是油脂醇解的有效催化剂,在优化工艺条件下甲酯产率达91%以上。  相似文献   

10.
魏铭  李艳  徐义 《热固性树脂》2014,(2):42-45,66
采用具有协同催化效应的乙酰丙酮铬与三乙胺复配催化合成了可紫外光固的环氧豆油丙烯酸树脂,对影响合成的各因素进行了探讨,并通过红外光谱,核磁共振氢谱,碳谱对合成产物进行了表征。结果表明:复配催化剂m(乙酰丙酮铬)∶m(三乙胺)=2∶1,用量为环氧大豆油与丙烯酸质量的0.3%时具有较高催化活性,n(环氧基)∶n(丙烯酸)=1.1∶1,阻聚剂对甲氧基苯酚的质量分数为0.1%,110℃反应5.5 h,酯化率达95%以上。经紫外光固化涂膜光滑平整,硬度3H,附着力2级,具有较好的柔韧性。  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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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   

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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