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以四氢苯酐、二甘醇、2-乙基己醇、双氧水为原料,钛酸四正丁酯、甲酸为催化剂,分别经酯化和环氧化两步合成功能化环氧聚酯增塑剂环氧聚四氢苯酐二甘醇酯。考察了酯化反应温度、时间、醇酸摩尔比、封端剂用量、催化剂用量以及环氧化反应温度、时间、双氧水用量、甲酸用量对环氧聚四氢苯酐二甘醇酯合成的影响。采用红外光谱仪(FT-IR)、核磁共振仪(1H-NMR)、热重分析仪(TGA)对产品的结构和热稳定性等进行了表征。结果显示,最佳酯化反应条件为:四氢苯酐、二甘醇、2-乙基己醇的摩尔比为1.0:1.25:0.50,催化剂用量为酸酐质量的0.80%,反应温度200℃,反应时间6 h。最佳环氧化条件为:聚四氢苯酐二甘醇酯、甲酸、H2O2的质量比为1.0:0.50:0.90,反应温度50℃,反应时间1 h。产品环氧值>1.40%,碘值<4.0 g(100g)1,具有较好的流动性和热稳定性,加入PVC树脂中后,有效地提高了PVC的热稳定性。 相似文献
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新型环保增塑剂环氧脂肪酸甲酯合成研究 总被引:3,自引:0,他引:3
研究了环保增塑剂环氧脂肪酸甲酯的合成工艺及影响因素,其影响因至少包括甲酸用量、H2O2用量、反应温度、反应时间等对产物环氧值的影响. 相似文献
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以H2O2为氧化剂,N-TS-1为催化剂催化1-己烯环氧化合成了1,2-环氧己烷。研究了温度、H2O2用量、催化剂用量以及反应时间对反应的影响,较优化的反应条件为:反应温度343 K,H2O2用量0.8 mol/L,催化剂用量10.7 g/L,反应时间5 h。在优化的条件下,H2O2的转化率为58.1%,H2O2的选择性为93.9%,1-己烯的转化率为52.7%,1,2-环氧己烷的选择性为94.3%。 相似文献
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采用盐酸H2O2/HCOOH法,在微通道反应器内对不饱和脂肪酸甲酯进行环氧化反应。考察了双氧水用量、甲酸用量、反应温度及催化剂用量对反应的影响,得到最优的反应条件为:m(脂肪酸甲酯):m(甲酸):m(双氧水)=1:1.5:2,反应温度40℃,催化剂浓盐酸质量分数为3%(即浓盐酸质量占原料脂肪酸甲酯质量的百分数,下同),反应时间为110 s。在该条件下,产品环氧值为4.32%。 相似文献
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将亚麻油酸与环氧树脂E-51进行开环反应制得了环氧酯,然后将其替代部分多元醇参与水性醇酸树脂的制备,并利用红外光谱对产物结构进行了表征。重点考察了环氧酯的合成工艺及环氧酯用量对树脂、漆膜各项性能的影响。结果表明,环氧酯最优合成工艺条件为:反应温度110℃,反应时间4 h,四丁基溴化铵用量为反应物总质量的1%,在该条件下,合成树脂的酸值为10.3 mg KOH/g;当环氧酯用量为醇酸树脂总质量的10%时,树脂及其漆膜的综合性能最优,且通过TG测试表明,环氧改性后水性醇酸树脂漆膜的热稳定性得到明显改善。 相似文献
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以生物基腰果酚(cardanol)为原料,对甲苯磺酸为催化剂,与乙酸酐进行酯化反应得到腰果酚乙酸酯(CA);然后,以甲酸为催化剂,双氧水为氧源合成环氧腰果酚乙酸酯(ECA)。考察了双氧水的质量分数、甲酸和双氧水用量、反应温度、反应时间等对产品环氧值的影响。确定了最佳工艺条件为:质量分数70%H2O2,n(甲酸)∶n(H2O2)∶n(CA中双键)=0.2∶1.5∶1、反应温度为65℃、反应时间为6 h。在最优条件下得到的产品为黄色透明油状液体,其环氧值可达到6.8%。采用傅里叶变换红外光谱(FTIR)对CA及ECA进行结构表征,并测定了ECA的酸值、加热减量、黏度、热重曲线等。结果表明,ECA符合环保增塑剂的产品性能要求。 相似文献
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酶催化合成高纯度甘油中碳酸单酯 总被引:3,自引:0,他引:3
研究了无溶剂体系中脂肪酶LRI催化合成甘油中碳酸单酯(MG)。得到适宜的反应条件为:反应温度57℃,n(酸)∶n(甘油)=1∶1 1,加酶量100U/g(酸),甘油初始含水量w(H2O)=12%,封闭物系反应4h转敞开物系反应6h。产物中甘油中碳酸单酯质量分数w(MG)=42 20%。将n(酸)∶n(甘油)降低至1∶9,反应时间缩短至4h,粗产物经脱甘油和脱酸处理,可获得高纯度甘油中碳酸单酯。纯化后产品中基本不含游离酸及甘油,其中甘油中碳酸单酯质量分数w(MG)=73 65%。过量加入的甘油全部可以回收利用,其平衡转化率降低不超过2%。 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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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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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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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
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中蓝晨光化工研究院有限公司《塑料工业》编辑部 《塑料工业》2009,37(3)
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
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中蓝晨光化工研究院《塑料工业》编辑部 《塑料工业》2007,35(3):1-25,67
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