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1.
通过硅氢加成反应合成了丙烯酸酯改性有机硅流平剂,研究了合成反应条件,利用红外光谱(FT-IR)及核磁共振氢谱(1H-NMR)对制得的产物进行了结构表征,探讨了不同丙烯酸酯制得的改性有机硅流平剂的表面性能。结果表明:适宜的合成条件为反应时间为7 h,反应温度为100℃,催化剂用量为20μg/g,反应物比例为n(Si—H)∶n(CC)=1∶1.2。在此条件下,含氢硅油中Si—H的转化率达92.50%。表面性能研究表明:自制的丙烯酸酯改性有机硅流平剂产品能有效降低丙烯酸清漆的表面张力,同时其涂膜具有较好的鲜映性、光泽及滑爽度等表面流平性能。  相似文献   

2.
张晓利  赵杨锋  闫俊 《应用化工》2012,41(7):1227-1228,1231
以9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物(DOPO)和丙酮为原料,合成10-(异丙基-2-醇)-9,10-二氢-9-氧杂-10-膦杂菲-10-氧化物。考察了原料摩尔比、反应温度和反应时间对产物收率的影响。结果表明,较优工艺条件为:n(丙酮)∶n(DOPO)=12∶1,反应温度为50℃,反应时间为30 min时,DOPO的转化率为99%,目标产物收率为90%。  相似文献   

3.
以端环氧基烯丙基聚醚、含氢硅油为原料,采用第二代铂金催化剂,通过硅氢加成反应制备环氧基改性硅油。研究了反应时间、反应温度、物料配比对反应转化率的影响。通过单因素试验得到最佳反应条件为:反应时间7 h、反应温度100℃、含氢硅油与端环氧基聚醚的摩尔比为1∶1.1。在此条件下含氢硅油的转化率为91%。红外表征证实,产物接上了端环氧基烯丙基聚醚。  相似文献   

4.
以无水柠檬酸和乙酸酐为原料合成柠檬酸酐,通过单因素试验利用滴定法考察投料摩尔比、反应温度以及溶剂用量对反应转化率和收率的影响。结果表明:反应温度为52℃,n(乙酸酐)∶n(无水柠檬酸)=1.2∶1,n(乙酸)∶n(无水柠檬酸)=1.0∶1,反应时间为1.5 h时,柠檬酸酐收率达88.8%。利用红外光谱、核磁共振氢谱和质谱表征了合成产物,证明其为五元环状柠檬酸酐。  相似文献   

5.
以α-十二烯、二苯醚及氯磺酸为原料合成双十二烷基二苯醚双磺酸盐。考察了合成过程中的烷基化和磺化反应的工艺条件。结果表明双烷基化的较佳反应条件是:n(二苯醚)∶n(α-十二烯)=1.0∶2.2,反应温度为70℃,反应时间5 h,烷基化的产率达83.25%;磺化的较佳反应条件是:反应时间60 min,n(烷基二苯醚)∶n(氯磺酸)=1∶2.6,反应温度为40℃,磺酸基的数目为1.842.并对所得产物进行了表征。最后考察了合成样品的表面化学性能。  相似文献   

6.
以异丙醇为溶剂、氯铂酸为催化剂,将单烯丙基封端聚氧乙烯聚氧丙烯醚(AEP)、单烯丙基封端聚氧乙烯聚氧丙烯环氧基醚(AEPH)和单烯丙基封端聚氧乙烯氧聚丙烯乙酰基醚(AEPC)同时与含氢硅油进行硅氢加成反应,合成了羟基封端聚醚、环氧基封端聚醚和乙酰基封端聚醚共改性硅油破乳剂。通过IR和1H NMR对产物结构进行表征,证实得到了预期产物。通过单因素实验法考察了碳碳双键与硅氢键的量之比[n(CC)∶n(Si—H)]、反应时间、反应温度和催化剂用量对活性氢转化率的影响,确定的最佳反应条件为:n(CC)∶n(Si—H)=1.20∶1,反应时间6 h,反应温度100℃,催化剂用量40μg/g(相对于反应物总质量),在此条件下活性氢转化率达到93.72%。将该聚醚改性硅油进行原油破乳性能测试,结果显示,在聚醚改性硅油用量为100 mg/L、破乳温度70℃条件下,加入聚醚改性硅油2 h后,原油脱水率达到90.54%,具有较好的破乳性能。  相似文献   

7.
以C5馏分中的环戊二烯为二烯体,顺丁烯二酸酐为亲二烯体,进行Dails-elder反应合成纳迪克酸酐,得到一种较好的外型纳迪克酸酐合成方法。并利用气相色谱-质谱联用法测定产物中外型产物的比率。通过正交试验对原料配比、滴加温度、滴加时间、反应温度、反应时间进行优化,得到最佳工艺条件:n(MA)∶n(CPD)=1.1∶1,滴加时间为4 0 min,滴加温度为2 5℃,反应时间为9 0 min,反应温度为3 5℃,此条件下合成产物的收率为84.79%,外式比例为49.21%。产物采用红外光谱进行了分析。  相似文献   

8.
本文以棕榈酸为主要原料,经磺化、皂化、酯化合成了棕榈酸-2-羟基-3-磺酸钠丙酯,对最佳工艺条件进行了考察,确定了中间产物3-氯-2-羟基丙磺酸钠的最佳合成条件为:环氧氯丙烷与亚硫酸氢钠物质的量比为0.87∶1,反应温度85℃,反应时间3.5 h,产物的转化率为80.4%;棕榈酸钠的最佳合成条件为:棕榈酸与氢氧化钠物质的量比为1∶1,反应温度85℃,反应时间4.5 h,产物的转化率为83%;目的产物棕榈酸-2-羟基-3-磺酸钠丙酯的最佳合成条件为:3-氯-2-羟基丙磺酸钠与棕榈酸钠物质的量比为1.1∶1,反应温度65℃,反应时间6.5 h,产物的转化率为86.82%。经红外光谱分析,确定产物为目的产物,通过测定其溶液的表面张力、乳化性等,表明该产物具有优良的表面活性和较好的乳化性、起泡性等。  相似文献   

9.
以乙二醇单烯丙基醚(YRC)和含氢双封头(M~HM~H)为原料,通过硅氢加成制得羟乙氧基丙基有机硅双封头,并采用FT-IR与~1H NMR表征了产物结构。结果表明,产物为羟乙氧基丙基有机硅双封头。较佳合成工艺为铂催化剂用量5×10~(-6),80℃反应8 h,n(M~HM~H)∶n(YRC)=1∶1.2,此条件下活性氢转化率可达98.9%。  相似文献   

10.
何婷  季永新 《化学与粘合》2013,(4):10-13,58
以含氢硅油与端烯丙基聚醚为原料,在氯铂酸的催化作用下,经硅氢加成反应合成了聚醚改性有机硅乳化剂。通过正交实验测定反应的转化率,探讨了反应时间、反应物比例、催化剂用量以及反应温度对反应的影响,并得出较适宜的反应条件为:反应时间为7h,n(Si—H):n(C=C)--1:1,催化剂用量为20μg/g,反应温度为130℃,在该条件下,含氢硅油中Si—H的转化率达96%。由此制备的表面活性剂能有效降低表面张力,具有优良的乳化性能。初步讨论了含氢硅油与聚醚反应生成的共聚物的阴离子化反应,合成了硫酸盐型阴离子表面活性剂,由于结构的差异,产物HLB值有所增加。  相似文献   

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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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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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