透明脱醇型单组分室温硫化硅橡胶

介绍了透明脱醇型单组分室温硫化硅橡胶的制备工艺及配方，对其硫化性能，操作性能，贮存稳定性及硫化胶机械性能和粘接性能进行了测试，结果表明，以端二甲氧基甲基硅基聚二甲基硅氧烷为基础聚合物，有机钛络合物作催化剂，适量的增粘剂构成的透明脱醇型ＲＴＶ－１硅橡胶的硫化，操作及贮存稳定性好，胶料黄变小，硫化胶机械强度，１００％定伸应力为０．４４ＭＰａ，拉伸强度２．３９ＭＰａ，扯断伸长率７０６％，对不锈钢，黄铜，     

透明脱醇型单组分室温硫化硅橡胶

介绍了透明脱醇型单组分室温硫化硅橡胶的制备工艺及配方，对其硫化性能、操作性能、贮存稳定性及硫化胶的机械性能和粘接性能进行了测试。结果表明，以端二甲氧基甲基硅基聚二甲基硅氧烷为基础聚合物、有机钛络合物作催化剂、适量的增粘剂构成的透明脱醇型ＲＴＶ－１硅橡胶的硫化、操作及贮存稳定性好，胶料黄变小，硫化胶机械强度：１００％定伸应力０．４４ＭＰａ，拉伸强度２．３９ＭＰａ，扯断伸长率７０６％，对不锈钢、黄铜、铝及塑料等材料的粘接均为１００％内聚破坏。     

蒙脱土/硅橡胶复合材料的力学和阻燃性能研究

采用熔融共混法制备了蒙脱土/硅橡胶硅橡胶,研究了蒙脱土对硅橡胶力学和阻燃性能的影响.结果表明,有机改性利于蒙脱土在硅橡胶中的分散,并提高硅橡胶的拉伸强度和阻燃性能;随着蒙脱土用量的增加,硅橡胶的拉伸强度和扯断伸长率均先增后减,氧指数先是剧增后缓增;当层间距d001为3.4 nm的有机改性蒙脱土的质量分数为6%时,硅橡胶的拉伸强度达到12.1 MPa,扯断伸长率为362%,氧指数为32.7%,硅橡胶的起始分解温度和终止分解温度分别比空白样提高83℃和13℃.     

EVA改性PE共混物力学性能和流变性能的研究

讨论了橡塑共混比、填料用量等因素对乙烯－醋酸乙烯共聚物（ＥＶＡ）改性ＰＥ共混物力学性能和流变性能的影响。试验结果表明，ＥＶＡ弹性体的加入降低了共混物的拉伸强度，提高了扯断伸长率及共混物熔体的流动性；活性碳酸钙的加入使共混物的拉伸强度、扯断伸长率和流动性下降；ＨＤＰＥ的加入提高了共混物的拉伸强度，但扯断伸长率和流动性下降。     

甲基乙烯基硅橡胶／有机蒙脱土母炼胶纳米复合材料

上海工程技术大学的王锦成等人采用溶液插层法和母炼胶混炼工艺制备了甲基乙烯基硅橡胶（MVQ）／有机蒙脱土母炼胶（OMMT—MB）纳米复合材料。MVQ／OMMT—MB纳米复合材料中的OMMT完全剥离,且均匀分散在MVQ基体中;当OMMT质量分数为20％时,MVQ／OMMT—MB复合材料的拉伸性能优于MVQ／OMMT复合材料,拉伸强度和扯断伸长率分别增大至1．41MPa、490％;     

甲基乙烯基硅橡胶／有机蒙脱土母炼胶纳米复合材料

上海工程技术大学的王锦成等人采用溶液插层法和母炼胶混炼工艺制备了甲基乙烯基硅橡胶（MVQ）／有机蒙脱土母炼胶（OMMT—MB）纳米复合材料。MVQ／OMMT—MB纳米复合材料中的OMMT完全剥离,且均匀分散在MVQ基体中;当OMMT质量分数为20％时,MVQ／OMMT—MB复合材料的拉伸性能优于MVQ／OMMT复合材料,拉伸强度和扯断伸长率分别增大至1．41MPa、490％;     

纳米导电纤维填充硅橡胶的性能

在乙烯基甲基硅橡胶（ＶＭＱ－１１０）中加入自制的纳米乙炔导电纤维（Ｎａｎｏ），可制备出性能良好的导电橡胶，实验表明，在ＶＭＱ－１１０中加入１０～３５份Ｎａｎｏ其混炼胶的导电性能接近导电乙炔炭黑混炼胶，且混炼胶柔软，加工性好，当Ｎａｎｏ用量大于３０份时，硫化胶的ρｓ小于１０＾３Ω，加入５０份ρＶ降至１０Ω．ｃｍ；随着Ｎａｎｏ用量增加，硫化胶的硬度，拉伸强度都增加，扯断伸长率呈线性下降。     

脱醇型单组分密封胶的制备及粘附性能的研究

文章研究制备脱醇型单组分硅橡胶,采用纳米碳酸钙填料进行补强,研究了碳酸钙的种类、用量对脱醇型硅橡胶性能的影响,结果表明脱醇型硅橡胶的拉伸强度随碳酸钙用量的增加而增大,在碳酸钙用量在130质量份时强度和粘度达到平衡最佳值,并研究了几种偶联剂对硅橡胶强度的影响,以及不同基材上的粘接性能。     

能粘PE的RTV硅橡胶的研制

研究了能粘ＰＥ的单包装ＲＴＶ硅橡胶，讨论了填料的选择、组合与表面处理；合成了特殊结构的有机硅偶联剂。制得的胶粘剂表面固化时间２５￣３０ｍｉｎ，固化后的拉伸强度为３．１ＭＰａ，扯断伸长率３００％，ＰＥ与玻璃的粘接良好，较好地解决了新颖汽车灯具ＰＥ壳体与玻璃罩的粘接密度。     

补强填料对裸导线涂覆硅橡胶性能的影响

以α,ω-二羟基聚二甲基硅氧烷为基料,碳酸钙或气相法白炭黑为补强填料,制得绝缘涂覆用硅橡胶,探讨了补强填料的种类和用量对硅橡胶性能的影响.结果表明,采用轻质纳米碳酸钙作补强填料的硅橡胶触变性更好,拉伸强度、拉断伸长率更高;采用重质碳酸钙作补强填料的硅橡胶无触变性,拉伸强度、拉断伸长率均较低;采用70份纳米碳酸钙作补强填...     

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。