掺杂氧化锌晶须对工程塑料抗静电性的影响

采用新的铝掺杂方法,降低了氧化锌晶须电阻率,研究了铝掺杂对氧化锌晶须电阻率的影响。含20%掺量的氧化铝使氧化锌晶须的表面电阻率从107～108Ω降低到1.6×106Ω,体积电阻率从108～109Ω·cm降低到7.1×105Ω·cm;研究了掺杂氧化锌晶须对塑料抗静电性能的影响,铝掺杂氧化锌晶须的添加量为8%(质量分数),使环氧树脂的表面电阻率降低到7.2×1010Ω;铝掺杂氧化锌晶须的添加量为12%(质量分数),使聚苯硫醚的表面电阻率降低到2.0×1010Ω。     

铝掺杂氧化锌晶须/环氧树脂抗静电性能研究

采用新的铝掺杂方法,降低了氧化锌晶须的本体电阻率;研究了铝掺杂对氧化锌晶须电阻率的影响。含20%掺量的氧化铝使氧化锌晶须的表面电阻率从107~108Ω降低到1·6×106Ω,体积电阻率从108~109Ω·cm降低到7·1×105Ω·cm;研究了铝掺杂氧化锌晶须对环氧树脂抗静电性能的影响,铝掺杂氧化锌晶须的添加量为8%,使涂层的表面电阻降低到7·2×1010Ω。     

T-ZnOw在水性聚氨酯涂料中的应用研究

采用铝掺杂四针状氧化锌晶须作为功能性填料制备得到多功能水性聚氨酯涂料,其具有良好的抗静电性能、高耐磨性能以及优异的自清洁功能。采用硅烷偶联剂制备了分散性良好的晶须,并研究了晶须含量对涂层抗静电性能和耐磨性能的影响。当晶须含量为8%时,涂层的体积电阻率和表面电阻率分别从10~(15)Ω·cm和10~(16)Ω降低至10~7Ω·cm和10~7Ω,且涂层的磨耗量从22 mg降低至12 mg;此外,铝掺杂氧化锌晶须/聚氨酯涂层具有光催化功能和一定的自清洁功能。     

掺杂型ZnOw/纳米ZnO并用对PP性能的影响

研究了铝掺杂氧化锌晶须(ZnOw)和纳米ZnO对聚丙烯共混物力学性能和抗静电性能的影响.结果表明,铝掺杂氧化锌晶须能提高聚丙烯的冲击强度、拉伸强度和表面电阻率.纳米ZnO与掺杂氧化锌晶须并用能协同增强和增韧聚丙烯,纳米ZnO/掺杂氧化锌晶须/聚丙烯的质量比为2/16/82时,共混体系的综合力学性能较好.     

氧化锌晶须渗入聚丙烯腈纤维的抗静电性能

在乳液中悬浮的氧化锌晶须渗入聚丙烯腈纤维中,起到抗静电作用,聚丙烯腈纤维的体积比电阻率可降到4.1×108Ω.cm;四针状和单针状的氧化锌晶须的渗入能力不同,得到抗静电性能不同;渗入工艺简单方便,同时解决了氧化锌晶须添加入聚丙烯腈纺丝原液所造成的喷丝孔阻塞问题。     

超细氧化锌改性制备高导电性粉末

以纤锌矿型氧化锌为原料,用后合成法制备了铝掺杂氧化锌导电粉末并在抗静电环氧树脂漆中应用,采用x-射线衍射（XRD）、扫描电镜（SEM）、化学分析等方法表征导电氧化锌的晶体结构、形貌和化学组成。结果表明,后合成法保持了氧化锌的纤锌矿结构,氧化锌的表面形貌发生了明显的变化。电阻测试结果表明白色氧化锌的电阻率从10Ω·cm降到了10^2Ω·cm,Al掺杂量和理论计算结果相符。抗静电应用结果表明,在氧化锌添加量为20％时,薄涂漆膜的表面电阻为10^6Ω。     

四角状氧化锌晶须／聚丙烯复合材料的导电性能研究

采用热压成型工艺制备了氧化锌晶须(T-ZnOW)/聚丙烯(PP)复合材料,研究了晶须用量、不同偶联剂处理对复合材料导电性能、介电性能的影响。研究结果表明,T-ZnOW能有效提高PP树脂的导电性能;随着氧化锌晶须含量的增加,复合材料的体积电阻率迅速下降。当v(T-ZnOW)达到3%时,复合材料电阻率降低到109Ω.cm以下,可以满足一般抗静电材料的要求。     

矿用高分子泡沫材料抗静电研究

研究了抗静电剂及其协同作用对高分子(聚氨酯)泡沫的抗静电性能的影响。本实验讨论了抗静电剂A及十六烷基三甲基溴化铵对半硬质聚氨酯泡沫的体积电阻率(ρv)、表面电阻率(ρs)以及力学性能的影响。结果表明,以聚醚多元醇10 g为基准时,抗静电剂A和十六烷基三甲基溴化铵的同时使用,当抗静电剂A的用量为0.6 g和十六烷基三甲基溴化铵的用量为0.25 g时,聚氨酯泡沫的表面电阻率从7.33×1011Ω降低到6.1×108Ω。聚氨酯泡沫的表面电阻率可以降低到满足抗静电的需要,而同时其力学性能也达到行业的标准要求。     

添加氧化锌晶须的聚丙烯腈纤维抗静电性研究

在聚丙烯腈纺丝原液中添加四针状氧化锌晶须对聚丙烯腈纤维抗静电性具有改善作用。研究表明:氯化锌晶须添加量为1%(相对于聚丙烯腈干粉质量)就可以使聚丙烯腈纤维达到抗静电要求,体积比电阻率为5.4×1010赘·cm。     

抗静电聚甲醛的研究

研究了A,B,C三类抗静电剂对聚甲醛(POM)力学性能及抗静电性能的影响。结果表明:A质量分数为6%时,POM的表面电阻率为10~(12)Ω。C对POM的抗静电性能改善明显,可将POM的表面电阻率降低到10~7~10~8Ω,但力学性能下降了50%~60%。B质量分数在15%时,POM表面电阻率为1.1×10~9Ω,力学性能下降15%~22%,可应用于一些对抗静电性能要求较高的场合。     

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。