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1.
采用BPO和FeCl3·6H2O为氧化剂,以苯胺(An)为原料在界面体系下采用“无模板”的方法制备了聚苯胺纳米纤维。探讨了温度、氧化剂浓度对PANI结构及形貌的影响,研究发现FeCl3可同时起到氧化剂和掺杂剂的作用,且氧化剂的浓度直接影响到电导率的高低和聚苯胺的微观结构。以相对低廉、简单的生产工艺来合成出电导率高、且有一定长径比的聚苯胺(PANI)纳米纤维。  相似文献   

2.
以聚(乙二醇)甲基丙烯酸酯、三氯氧磷以及三乙胺等为原料合成光固化亲水酸性磷酸酯(UV-PP),对合成的产物进行表征。以UV-PP为掺杂剂、过硫酸铵(APS)为氧化剂,原位聚合苯胺制备了可光固化的导电聚苯胺分散体。利用红外光谱(FT-IR)、紫外-可见分光光度计(UV-Vis)、X射线衍射(XRD)、四探针电阻测试仪和激光粒度仪对产物进行表征测试,研究了氧化剂与掺杂剂用量对聚苯胺的合成以及掺杂行为的影响。结果表明:当UV-PP与苯胺单体以及APS的物质的量比为9∶3∶1,UV-PP为去离子水质量的10%时,合成聚苯胺分散体的粒径为114.46nm,水溶性最好,在室温下放置6周后粒径大小变化小于70nm,且纯聚苯胺的电导率可达10.36mS/mm。  相似文献   

3.
以盐酸为掺杂剂、过渡金属盐为引发剂,制备了煤基聚苯胺(CPANI)和聚苯胺(PANI),探讨了掺杂引发剂及力化学作用对CPANI和PANI导电性能的影响,并研究了CPANI,PANI的红外光谱图.结果表明,在过渡金属盐的作用下,制备的CPANI,PANI具有一定导电性能,这表明过渡金属盐在一定程度上起到了引发苯胺单体聚合的作用,但相对过硫酸铵作为引发剂引发聚合的CPANI,PANI而言,导电性能有一定程度的下降.  相似文献   

4.
采用过硫酸铵(APS)为氧化剂在十二烷基苯磺酸(DBSA)微胶束中化学氧化制备纳米棒状聚苯胺;DBSA既起乳化剂也起掺杂剂的作用。制备的掺杂聚苯胺用红外光谱(FTIR)、紫外光谱(UV-vis)、X-射线衍射(XRD)和扫描电镜(SEM)进行了表征;透射电镜(TEM)下首次观察到了聚苯胺的有序排列结构,晶面间距为5.99 Å。考察了掺杂剂/苯胺、氧化剂/苯胺的摩尔比和反应温度、时间等对聚苯胺电导率影响,最高电导率达到了0.72 S/cm。透射电镜怎能看到5.99  相似文献   

5.
不同酸掺杂聚苯胺的性能研究   总被引:2,自引:0,他引:2  
合成了盐酸(HC1)、氨基磺酸(NH2SO3H)、十二烷基苯磺酸(DBSA)掺杂的聚苯胺(PANI),探讨了酸用量、氧化剂用量、反应时间以及反应温度等因素对产物电导率的影响,并对这3种酸掺杂的聚苯胺的压片电阻和热稳定性进行了比较.结果表明:当c(HCl)=0.5 mol·L-1,反应时间为6 h,n(APS)∶n(An)为1.0,在1 ℃左右下所得HCl掺杂的PANI的电导率为1.98 S·cm-1;当c(NH2SO3H)=1.0 mol·L-1,反应时间为6 h,n(APS)∶n(An)为2.0,在2 ℃左右下所得NH2SO3H掺杂的PANI的电导率为0.26 S·cm-1;当c(DBSA)=1.0 mol·L-1,反应时间为8 h,n(APS)∶n(An)为2.0,在2 ℃左右下所得DBSA掺杂的PANI的电导率为0.98 S·cm-1.对于产物的固体压片电阻,HC1掺杂PANI最小为10 Ω,NH2SO3H掺杂PANI最大为120 Ω.而对于产物的热稳定性,NH2SO3H和DBSA掺杂的PANI具有较好的环境稳定性,要好于HC1掺杂的PANI.  相似文献   

6.
XPS对电导性纳米聚苯胺的性能表征   总被引:1,自引:1,他引:0  
以微乳液聚合法合成了导电性纳米聚苯胺(PANI),讨论了乳化剂的用量对聚苯胺电导率的影响,并用XPS对其性能进行了表征.结果表明:当十二烷基苯磺酸钠(SDBS)和苯胺(An)的摩尔比在1左右时, PANI的电导率有最大值;SDBS以两种方式存在,即掺杂PANI的SDBS和自由独立于PANI的SDBS;在一定酸性SDBS掺杂的条件下,(-N= NH )/N比率决定PANI的电导率.  相似文献   

7.
导电聚苯胺复合膜的研制   总被引:1,自引:0,他引:1  
以聚甲基丙烯酸甲酯(PMMA)为基质,过硫酸铵为氧化剂,十二烷基苯磺酸为掺杂剂,进行苯胺的原位氧化聚合,制备聚苯胺(PAn)/PMMA复合材料,采用溶液浇铸法制成了性能优良的可溶性导电复合膜,电导率达10^-2S/cm;考察了反应条件对复合膜电导率的影响,并进行了环境稳定性测试,用红外光谱进行了复合膜的结构表征,用元素分析法测定了复合膜的组成,结果表明复合的聚苯胺存在—饱和值,超过饱和值,对电导率影响不大。  相似文献   

8.
以碳球(CS)为核,采用"grafting from"法制备了碳球@聚丙烯酸(CS@PAA);再以其为掺杂剂制备了碳球@聚丙烯酸掺杂聚苯胺(CS@PAA/PANI),并通过FTIR、UV-Vis、SEM、XPS及电导率等对CS@PAA/PANI进行结构和性能表征.结果表明,引入掺杂剂CS@PAA后,可以得到球状和纤维状...  相似文献   

9.
原位聚合沉积制备聚苯胺/聚酰亚胺/聚苯胺复合膜   总被引:1,自引:0,他引:1  
以聚酰亚胺(PI)膜为基体,采用分散聚合原位沉积方法制得聚苯胺/聚酰亚胺/聚苯胺(PANI/PL/PANI)三层复合膜.复合膜表面PANI层外观质量优异,电导率达10~0S/cm.实验结果表明:加入高浓度空间稳定剂(聚乙烯吡咯烷酮,PVP)、调整氧化剂(过硫酸铵,APS)和介质酸(盐酸)的用量可制得表面质量和电导率高的复合膜.较适宜的反应条件为稳定剂质量浓度4%,APS与苯胺(An)的物质的量比为2:4,盐酸浓度为0.5 mol/L.  相似文献   

10.
在不同磁场强度下,用过硫酸铵(APS)为氧化剂,磺基水杨酸(SSA)为掺杂剂合成导电聚苯胺(PAn),通过对PAn掺杂率的计算和电导率的测定,研究了氧化剂和掺杂剂浓度对PAn性能的影响。采用红外光谱、X射线衍射、粒径分析等研究了制备的PAn性能与结构。实验结果表明磁场对苯胺聚合的影响是正向的,氧化与掺杂条件的变化是影响电导率的重要因素。  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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