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1.
以萘为原料,采用AlCl3催化合成和热转化处理二步法制备了高软化点、低QI含量的优质萘系中间相沥青。通过分析表征不同条件下合成的萘沥青经热转化后所得中间相沥青的性质和中间相织构形态,重点研究了萘沥青的合成条件与其中间相热转化行为间的内在关系,以确定合成萘沥青的最佳工艺参数。结果表明,在合成温度240℃、合成时间6 h、催化剂用量10%的条件下合成的萘沥青在390℃恒温8 h后能得到100%的广域流线型的体中间相沥青,其软化点为244.6℃,QI含量仅为10.32%。  相似文献   

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以中温煤沥青(MTCP)和改质煤沥青(MCP)为原料,采用热聚合反应方法,在相同的反应时间下,研究不同反应温度下2种煤沥青的中间相热聚合行为。采用软化点仪、偏光显微镜、X射线粉末衍射仪(XRD)以及激光共焦拉曼光谱仪(Raman)对中间相沥青表征和分析。结果表明,2种煤沥青在相同工艺条件下呈现出相似的中间相聚合行为。偏光显微镜照片说明2种煤沥青聚合所得到的中间相类型均为镶嵌结构。XRD与Raman分析表明随着聚合温度的升高,中间相沥青内部芳香片层分子的取向性更好,排列更为规整。MTCP经过430℃、8 h聚合,可制备软化点为319℃的中间相含量高于80%的中间相沥青;MCP经过420℃、8 h聚合,可制备软化点316℃,中间相含量高于80%的中间相沥青。  相似文献   

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本文以改质沥青为原料,采用直接热缩合聚合和催化热缩合聚合反应的方法,在高压反应釜中,氮气气氛保护进行热缩合聚合反应,合成出沥青中间相。考查了不同热缩合温度和不同恒温时间对合成煤沥青中间相的影响,用软化点测定仪对煤沥青的软化点进行了测定,并利用偏光显微镜对中间相的光学结构进行了观察。研究结果表明:采用直接热缩合聚合反应,在热缩合温度400℃下,恒温时间为5h,得到软化点为250℃的光学各向异性含量较高的优质中间相。催化热缩合可以降低煤沥青热缩合聚合反应的温度,控制反应温度为330℃,反应时间7h时,得到软化点263℃的光学各向异性含量较高的优质中间相。  相似文献   

4.
中间相碳/Co复合微球的制备   总被引:1,自引:0,他引:1  
以煤沥青和乙酸钴为原料进行热缩聚反应,以吡啶为溶剂,分离制备出大小为20μm左右的中间相碳/Co复合微球,并研究了钴含量和热处理温度对复合微球结构的影响。研究结果表明,随着原料中乙酸钴含量的增加,制备出的复合微球钴含量增加。复合微球的X衍射图显示出明显的石墨碳和金属钴的衍射峰,2500℃石墨化后,复合微球中的钴仍能稳定存在。热处理过程中复合微球中钴对碳的石墨化有催化作用,钴含量越大,这种催化石墨化作用越明显。复合微球的TEM照片显示微球中钴颗粒大小为10~40nm,颗粒均匀分布在中间相碳基质中。  相似文献   

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文章采用以萘和三氟化硼与氟化氢为原料制备的齐聚物沥青,研究齐聚物沥青在中温条件下通过热缩聚制备出的低软化点,中间相含量高,纺丝性能良好的中间相沥青,探讨齐聚物沥青调制的时间,热缩聚反应的时间以及热缩聚反应的温度对于中间相沥青的影响。  相似文献   

6.
蒽油基沥青是人造炭/石墨材料的优质前驱体,对其热转化特性研究意义重大。本文采用多管井式电阻炉对蒽油基沥青进行常压热转化处理,通过工业分析、FTIR以及偏光显微镜对热转化过程中蒽油基沥青的族组成、结构参数及显微结构的变化规律进行了研究。结果表明:随着热转化温度的提高、时间的延长,蒽油基沥青产物的软化点、甲苯不溶物(TI)、喹啉不溶物(QI)、结焦值(CV)逐渐增大;通过偏光显微镜分析可知,当热转化温度达到440℃时,产物中开始出现中间相结构,并且随着热转化温度的升高和热转化时间的延长,中间相结构逐渐增多;蒽油基沥青产物的芳香性指数(I)与热转化温度和恒温时间均存在正相关关系。  相似文献   

7.
以深度裂解石油渣油为原料,采用两段热缩聚法可制得软化点为268℃,可编性良好的中间相沥青。本文详细考察了温度,时间对中间相沥青软化点,可编性,中间相沥青形态及碳化收率的影响,并初步探讨了两段热缩聚反应的机理。研究结果表明反应温度,时间对中间相沥青的结构和性能影响较大,选择适宜石油渣油,采用加压-真空两段热缩聚法,调整反应条件,可制得可纺性良好的中间相沥青。  相似文献   

8.
以精制煤焦油沥青为原料,采用常压热聚合法进行中间相转化。根据产物中中间相沥青与母体沥青之间的密度差,将中间相沥青分离出来。系统考察了热聚合温度和恒温停留时间对中间相沥青的收率、软化点、族组成和光学显微形态的影响,采用FT-IR分析技术分析了中间相沥青的官能团结构。实验结果表明:聚合温度430℃,聚合时间4 h,中间相沥青的软化点为316℃,w(QI)为74.62%,w(TI)为73.81%,收率为12.5%。  相似文献   

9.
高波  金锋 《燃料与化工》2012,43(3):34-35,38
以2种精制沥青(LSP和HSP)为原料,通过常压热转化反应,研究了热转化过程中产物的QI和TI随反应时间的变化规律.分析表明,随着反应温度的升高和反应时间的延长,沥青的各向异性组分不断增加.其中LSP沥青生成的中间相小球大于HSP沥青生成的中间相小球.400℃恒温9h,LSP沥青的软化点达到242℃,HSP沥青的软化点达到220℃.  相似文献   

10.
将AlCl3(10%)催化萘在200℃恒温5 h制得萘的齐聚物,齐聚物主要为萘的三聚体,并含有四聚体和五聚体;然后通过加入不同比例的供氢剂十氢萘在340℃下恒温5 h热缩聚制得中间相沥青。结果表明:当十氢萘加入量为10%时,所得的沥青中间相含量高(100%),残炭率高(64.1%),软化点较低(190℃),可溶性较强(甲苯可溶组分含量为60.4%,吡啶可溶组分含量为80.2%)。  相似文献   

11.
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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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   

16.
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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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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Inorganic/organic hybrid materials have considerable promise and are beginning to become a major area of research for many coating usages, including abrasion and corrosion resistance. Our primary approach is to prepare the inorganic phase in situ within the film formation process of the organic phase. The inorganic phase is introduced via sol-gel chemistry into a thermosetting organic phase. By this method, the size, periodicity, spatial positioning, and density of the inorganic phase can be controlled. An important aspect of the inorganic/organic hybrid materials is the coupling agent. The initial task of the coupling agent is to provide uniform mixing of the oligomeric organic phase with the sol-gel precursors, which are otherwise immiscible. UV-curable inorganic/organic hybrid systems have the advantages of a rapid cure and the ability to be used on heat sensitive substrates such as molded plastics. Also, it is possible to have better control of the growth of the inorganic phase using UV curing. It is our ultimate goal to completely separate the curing of inorganic and organic phases to gain complete control over the morphology, and hence optimization of “all” the coating properties. Thus far, it has been found that concomitant UV curing of the inorganic and organic phases using titanium sol-gel precursors afforded nanocomposite coatings which completely block the substrate from UV light while maintaining a transparent to visible light. Also, it has been found that the morphology of the inorganic phase is highly dependent on the concentration and reactivity of the coupling agent. Presented at the 82nd Annual Meeting of the Federation of Societies for Coatings Technology, October 27–29, 2004, in Chicago, IL.  相似文献   

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Ethanol and α-pinene were tested as attractants for large wood-boring pine beetles in Alabama, Florida, Georgia, North Carolina, and South Carolina in 2002–2004. Multiple-funnel traps baited with (−)-α-pinene (released at about 2 g/d at 25–28°C) were attractive to the following Cerambycidae: Acanthocinus nodosus, A. obsoletus, Arhopalus rusticus nubilus, Asemum striatum, Monochamus titillator, Prionus pocularis, Xylotrechus integer, and X. sagittatus sagittatus. Buprestis lineata (Buprestidae), Alaus myops (Elateridae), and Hylobius pales and Pachylobius picivorus (Curculionidae) were also attracted to traps baited with (−)-α-pinene. In many locations, ethanol synergized attraction of the cerambycids Acanthocinus nodosus, A. obsoletus, Arhopalus r. nubilus, Monochamus titillator, and Xylotrechus s. sagittatus (but not Asemum striatum, Prionus pocularis, or Xylotrechus integer) to traps baited with (−)-α-pinene. Similarly, attraction of Alaus myops, Hylobius pales, and Pachylobius picivorus (but not Buprestis lineata) to traps baited with (−)-α-pinene was synergized by ethanol. These results provide support for the use of traps baited with ethanol and (−)-α-pinene to detect and monitor common large wood-boring beetles from the southeastern region of the USA at ports-of-entry in other countries, as well as forested areas in the USA.  相似文献   

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