不同补强剂对氢化丁腈橡胶硫化胶性能的影响

以炭黑(N330)、蒙脱土(MMT)、有机蒙脱土(OMMT)、甲基丙烯酸镁(MgMA)、甲基丙烯酸锌(ZnMA)和齐聚酯等分别作为补强剂,制备相应的HNBR(氢化丁腈橡胶)硫化胶,并对硫化胶的力学性能、耐热老化性能和耐热性等进行了探讨。研究结果表明:ZnMA、MgMA或齐聚酯的综合补强效果相对较好;N330改性HNBR硫化胶的力学性能虽相对较好,但其耐热老化性能相对较差;MMT几乎无补强作用;OMMT能均匀分散在HNBR基体中,其与橡胶分子之间的相容性良好,故相应改性HNBR硫化胶的耐热性和耐热老化性能相对较好。     

丁腈橡胶耐热空气老化因素的对比研究

研究了补强剂、增塑剂和防老剂对丁腈橡胶耐热空气老化性能的影响。结果表明,采用低补强炭黑N774、炭黑N990与甲基丙烯酸镁或甲基丙烯酸锌(SR634)配合可以提高丁腈橡胶耐热空气老化性能;分别加入耐高温增塑剂TP-759、耐高温防老剂445和耐高温防老剂KY405能明显提高丁腈橡胶耐热空气老化性能;采用沉淀法白炭黑与甲基丙烯酸锌配合时,可以提高胶料耐热空气老化性能,但会明显降低胶料弹性。     

补强剂对酚醛树脂硫化BIIR性能的影响

探讨补强剂种类和用量对酚醛树脂硫化BIIR胶料性能的影响。结果表明，炭黑N330、N660和气相法白炭黑对酚醛树脂硫化BIIR胶料均有较好的补强效果。补强剂用量为60份时BIIR胶料的综合物理性能较好；炭黑N330补强BIIR胶料的耐热老化和抗溶胀性能最好。     

原位聚合插层法制备氢化丁腈橡胶/有机蒙脱土纳米复合材料

通过原位聚合和混炼插层法制备了氢化丁腈橡胶（HNBR）／有机蒙脱土（OMMT）纳米复合材料,并对其结构、力学性能和耐热空气老化性能进行了研究。结果表明,有机蒙脱土以插层／剥离共存的结构分散在橡胶基体中。在178℃×96h的热空气老化条件下,HNBR／OMMT纳米复合材料的耐热空气老化性能优于高耐磨炭黑填充的HNBR复合材料。     

炭黑对乙烯丙烯酸酯橡胶硫化胶性能的影响

研究炭黑品种和用量对乙烯丙烯酸酯橡胶(AEM)硫化特性、物理性能、耐热老化性能和耐油性能的影响。结果表明:随着炭黑粒径的增大,AEM胶料的焦烧时间延长,物理性能和耐热老化性能降低,耐油性能提高,炭黑N660/AEM胶料的综合性能最好;随着炭黑N660用量的增大,AEM胶料的焦烧时间缩短,物理性能先升高后降低,耐油性能提高,耐热老化性能降低,炭黑N660用量为60份时AEM胶料的综合性能较好;炭黑N550/N774并用比为40/40时,AEM胶料的综合性能较好。     

炭黑和碳纳米管对丁腈橡胶性能的影响

研究炭黑和碳纳米管对常温和高温下丁腈橡胶(NBR)物理性能和耐热空气老化性能的影响。结果表明,增大炭黑用量或加入碳纳米管,胶料的Payne效应增强,加工性能降低,常温下硫化胶的耐热空气老化性能变化不大;与常温相比,高温下硫化胶的物理性能和耐热空气老化性能显著降低。     

NR/炭黑/白炭黑/有机蒙脱土纳米复合材料的性能研究

将实验室自制的固相改性有机蒙脱土(OMMT)引入NR/炭黑/白炭黑体系中,并对复合材料性能进行研究.结果表明,OMMT(用量为6份)的加入可以显著改善NR/炭黑/白炭黑体系的加工性能、物理性能、耐热氧老化和耐屈挠性能,并降低动态疲劳生热.     

补强剂对酚醛树脂硫化BIIR性能的影响

探讨补强剂种类和用量对酚醛树脂硫化BIIR胶料性能的影响。结果表明，炭黑N330、N660和气相法白炭黑对酚醛树脂硫化BIIR胶料均有较好的补强效果，补强剂用量为60份时BIIR胶料的综合物理性能较好；炭黑N330补强BIIR胶料的耐热老化和抗溶胀性能最好。     

NR/有机蒙脱土/GMA纳米复合材料的制备与性能研究

采用胶乳接枝插层法制备NR／有机蒙脱土／甲基丙烯酸缩水甘油酯(GMA)纳米复合材料，并对其性能进行研究。结果表明，在NR胶乳与有机蒙脱土体系中加入GMA，并使之原位聚合，同时实现对NR的接枝和对有机蒙脱土的插层并与有机蒙脱土层间的基团产生化学结合，可以制备NR／有机蒙脱土／GMA纳米复合材料；采用胶乳接枝插层法制备的NR／有机蒙脱土／GMA纳米复合材料的物理性能和耐热氧老化性能优异，动态力学性能良好，热稳定性与NR胶料相差不大。     

热空气老化对补强氢化丁腈橡胶性能的影响

研究不同补强剂补强氢化丁腈橡胶(HNBR)在热空气老化过程中的物理性能和动态力学性能变化。结果表明:当补强剂用量均为30份时,甲基丙烯酸镁(MDMA)补强的HNBR硫化胶综合物理性能最好,甲基丙烯酸锌(ZDMA)补强的硫化胶次之,炭黑和白炭黑补强的硫化胶较差;ZDMA和MDMA补强的硫化胶耐老化性能较好;热空气老化后,不同补强剂补强的HNBR硫化胶的损耗因子峰值均有所降低,且老化时间越长,降低幅度越大;炭黑补强的HNBR硫化胶抗湿滑性能最佳,MDMA补强的硫化胶滚动阻力最低。     

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。