聚3,4-乙烯二氧噻吩/聚苯胺复合材料的制备与性能

以过硫酸铵(APS)和FeCl3为复合氧化剂,采用原位化学氧化聚合法合成了导电聚3,4-乙烯二氧噻吩/聚苯胺(PEDOT/PANI)复合材料,研究了苯胺浓度及加入时间、复合氧化剂配比和复合乳化剂配比对复合材料性能的影响,并对复合材料进行了分析. 结果表明,PEDOT/PANI复合材料合成的较佳工艺条件为：3,4-乙烯二氧噻(EDOT) 0.6 mol/L、复合氧化剂 0.6 mol/L(FeCl3:APS=1:2, mol)、复合乳化剂 0.4 mol/L(SDBS:CTAB=2:3, mol)、复合掺杂剂1.2 mol/L(H2SO4:SSA=4:1, mol)及苯胺0.8 mol/L, EDOT聚合2 h后加入苯胺溶液继续反应8 h. 复合材料的导电性、结晶性和热稳定性比纯导电聚合物好.     

复合氧化剂在合成导电聚苯胺中的应用

以苯胺为单体,采用(NH4)2S2O8和抗坏血酸组成的复合氧化剂,在硫酸水溶液中,用化学氧化法直接合成导电聚苯胺。系统地研究了复合氧化剂配比、硫酸的浓度、氧化剂浓度等因素对苯胺聚合反应的影响。结果表明,该方法聚合反应的最佳条件为:在10~25℃的温度范围内,不加氮气保护条件下,苯胺1.0 mol/L,H2SO41 mol/L,(NH4)2S2O81 mol/L,(NH4)2S2O8/抗坏血酸(C6H8O6)的配比为10∶1,合成了电导率达1.33 S/cm、产率达82.17%的聚苯胺。通过红外光谱和X衍射研究了通过不同氧化剂聚合得到聚苯胺的结构变化,结果表明,复合氧化剂氧化聚合得到的聚苯胺结晶比通过过硫酸胺作氧化剂聚合得到的聚苯胺结晶好,并且相应基团在红外光谱上发生红移。     

聚苯胺/涤纶导电织物的制备

将导电聚合物聚苯胺采用现场吸附聚合法吸附到涤纶织物表面上制备复合导电织物,通过单因素分析得出第一次聚合并掺杂的较优工艺条件为:苯胺浓度0.25mol/L,氧化剂过硫酸铵质量浓度0.02g/mL,掺杂剂盐酸浓度2.5mol/L,反应时间2h,反应温度20℃。若将经第一次聚合掺杂处理的织物在相同工艺参数条件下再经过第二次掺杂,则能显著提高导电织物的电学性能。从光学显微镜里可以看到聚苯胺沉积在纤维表面上,形成致密且均匀分布的连续导电膜。     

H_2O_2-Cu~(2+)化学氧化法合成聚苯胺纳米纤维

以硫酸铜(CuSO4)为催化剂,H2O2为氧化剂,通过"无模板"化学氧化聚合制备出聚苯胺纳米纤维。研究了温度、H2O2的浓度、催化剂的浓度对聚苯胺的产率、电导率、反应速度的影响,确定出最佳聚合反应条件为:苯胺0.1 mol/L,盐酸1 mol/L,H2O2 0.15 mol/L,CuSO40.05 mol/L,反应时间为24小时。在此条件下合成聚苯胺的产率为58.2%,电导率为1.98 S/cm。红外光谱和紫外-可见光谱确定了合成聚苯胺的结构,扫描电镜图中发现制备导电聚苯胺呈纤维状,直径大约为60~80 nm,长度大约为400 nm。     

原位吸附聚合法制备聚苯胺/废弃丁羟黏合剂复合导电材料

采用原位吸附聚合法制备了聚苯胺/废弃丁羟黏合剂导电复合材料,考察了苯胺单体质量分数、掺杂质子酸浓度、氧化剂浓度、反应时间和反应温度对复合产物导电性的影响,并用红外光谱仪对复合物的结构进行了表征。结果表明,较佳反应条件为苯胺单体质量分数为20%,掺杂质子酸对甲苯磺酸浓度为0.1 mol/L,氧化剂浓度为0.16 mol/L,反应时间为2 h,反应温度为10℃。在此条件下处理废弃丁羟黏合剂可使体积电阻率由原来的1011Ω·m降低到105Ω·m。     

合成条件对聚苯胺成纤性能的影响

以苯胺为单体、过硫酸铵为氧化剂、在盐酸水溶液中化学法合成聚苯胺 ,研究的重点是确立一个能够适合纺丝要求的合成参数体系。合成的聚苯胺重均相对分子质量达 2 9× 10 4。以不同条件下合成的聚苯胺为原料湿法纺制了聚苯胺导电纤维。     

有机磷酸酯掺杂聚苯胺的研究

以有机磷酸酯为掺杂剂、过硫酸铵为引发剂,采用化学氧化法合成导电聚苯胺。在苯胺浓度为0．1mol/L、有机磷酸酯浓度为0．3mol／L、过硫酸铵浓度为0．12mol/L、温度10℃、聚合反应时间3．5小时的条件下,合成了电导率达0．42s/cm的聚苯胺。采用红外光谱和X－射线衍射对其结构进行了表征。     

2-甲基-6-乙基苯胺焦油合成可溶性导电取代聚苯胺的工艺研究

以2-甲基-6-乙基苯胺(MEA)生产中的废弃物焦油为原料,通过化学氧化法合成了可溶性导电取代聚苯胺;利用傅立叶变换红外光谱(FTIR)、扫描电镜(SEM)等技术对样品的结构进行了表征。考察了酸浓度、氧化剂用量、聚合反应时间、聚合反应温度等合成条件对取代聚苯胺导电性能的影响,并考察了样品的溶解性能。结果表明,当盐酸浓度为1 mol/L,氧化剂/焦油物质的量比为1∶1,反应温度为10℃,反应3 h得到的取代聚苯胺样品电导率达到2.51×10~(-4)S/cm,且样品在常用有机溶剂中溶解性能良好。     

苯胺在聚醋酸乙烯酯中的聚合研究

以过硫酸铵为氧化剂,十二烷基苯磺酸为掺杂剂,将苯胺在聚醋酸乙烯酯(PVAc)基质中进行原位氧化聚合,制备导电聚苯胺PAn/PVAc复合材料,采用溶液浇铸法制成可溶性导电复合膜,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,用扫描电镜对复合膜的表面形态进行了观察。     

电化学合成聚苯胺-天然石墨复合材料工艺研究

通过单因素实验确定电化学合成聚苯胺-天然石墨复合材料工艺范围和操作条件,苯胺浓度为2.5 mol/L,硫酸浓度为3.0~5.0 mol/L,石墨质量浓度为0.5~1.0 g/L,聚合电流密度为0.16~0.18 A/dm2,t为3~5 min。并对复合膜层与本征态聚苯胺进行电导率测试,扫描电子显微镜观察和光谱仪红外表征。结果表明:聚苯胺-石墨复合材料的导电率有所提高,石墨掺杂到聚苯胺膜层中,改善了复合材料的性能。     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。