国产稀土顺丁橡胶结构与性能的研究

对不同门尼粘度的国产稀土顺丁橡胶(NdBR)的微观结构与基本性能进行研究,并与镍系顺丁橡胶(NiBR)进行对比。结果表明:与NiBR相比,NdBR的相对分子质量大、相对分子质量分布指数小、分子链线性程度高;生胶的抗机械降解性能好,冷流性低;混炼胶的硫化速度较快,非牛顿性比较明显;硫化胶的强伸性能、撕裂强度和回弹值较高,耐磨性能好,压缩生热和滚动阻力较低。高门尼粘度的NdBR49的综合性能比低门尼粘度的NdBR46好。     

国产稀土顺丁橡胶的性能

研究了中国石油锦州石化公司以环烷酸钕和新癸酸钕催化体系生产的3种稀土顺丁橡胶(NdBR)的生胶,混炼胶,硫化胶的冷流、应力-应变、混炼、生热、抗湿滑以及黏弹性等,并与镍系顺丁橡胶(NiBR)进行了对比。结果表明,NdBR不仅混炼行为优于NiBR,而且硫化胶的强伸性能、抗湿滑性能和滚动阻力等都优于后者。用新癸酸钕催化体系所得NdBR的各项性能优于用环烷酸钕体系者。     

不同结构顺丁橡胶/溶聚丁苯橡胶并用胶的性能研究

研究不同结构顺丁橡胶(BR)[镍系BR(NiBR)牌号9000,钕系BR(NdBR)牌号CB24,SKD-NdII,Nd22EZ和Nd24EZ]对BR/溶聚丁苯橡胶(SSBR)并用胶性能的影响。结果表明:5种牌号BR的顺式1,4-结构摩尔分数基本一致(约为0. 96);采用NiBR的硫化胶性能与采用NdBR的硫化胶无明显差别,甚至部分性能略优;采用CB24的硫化胶物理性能、耐疲劳裂纹扩展性能和抗切割性能较好,抗湿滑性能优良,但滚动阻力较大;采用Nd24EZ的硫化胶撕裂强度较大,裂纹扩展速率较小;采用Nd22EZ的硫化胶抗湿滑性能较好,滚动阻力较小;采用Nd22EZ与Nd24EZ的硫化胶中白炭黑的分散性较好。     

钕系BR的基本特性与应用性能试验

对锦州石油化工公司生产的3种不同门尼粘度的钕系BR（NdBR)从微对结构到生胶混炼性能,硫化胶静态和动态性能等进行了全面的剖析试验,结果表明,与镍系BR（NiBR)相比,NdBR的平均相对分子质量高,混炼胶强度与挺性明显改善,但挤出工艺稍差,硫化胶拉伸强度,弹性,生热,滚动阻力,动态力学等性能均良好,显示了典型的钕系BR性能特征,NdBR是一种比NiBR更为优良的BR。     

钕系顺丁橡胶的性能研究

考察国产钕系顺丁橡胶（NdBR）各项性能,并与进口NdBR及镍系顺丁橡胶（NiBR）进行对比。结果表明：与NiBR相比,NdBR具有较高的顺式1,4-结构含量和平均相对分子质量,相对分子质量分布较窄;NdBR与炭黑的结合能力强,加工性能好;NdBR的门尼焦烧时间和硫化速率均能满足安全加工的需要;国产NdBR硫化胶的物理性能可达国外同类产品水平。     

新型钕系BR的性能研究

研究新型钕系BR（Z-NdBR）生胶、混炼胶和硫化胶的性能，并与钕系BR（NdBR）和镍系BR（NiBR）进行对比。结果表明，与NdBR和NiBR相比，Z-NdBR具有较窄的相对分子质量分布和较规整的线形结构，分子的自由链末端数较少；混炼性能较优，但硫化速度快，易焦烧；强伸性能、撕裂强度和回弹值较高，压缩生热较低，具有较好的综合性能。     

SSBR/NdBR和SSBR/NiBR并用胶的动态压缩性能研究

对比研究溶聚丁苯橡胶(SSBR)/稀土顺丁橡胶(NdBR)和SSBR/镍系顺丁橡胶(NiBR)并用胶在动态压缩条件下的形变、生热及粘弹性。结果表明:随着顺丁橡胶(BR)用量的增大,SSBR/BR并用胶的动态压缩形变减小,弹性改善,压缩疲劳温升升高,储能模量增大,损耗因子(tanδ)减小,损耗模量先减小后增大;与SSBR/NiBR并用胶相比,SSBR/NdBR并用胶具有更低的压缩疲劳温升、更小的压缩形变和tanδ,形变回复能力更优,生热更低。     

钕系顺丁橡胶在全钢巨型工程机械子午线轮胎胎侧胶中的应用

试验研究两种钕系顺丁橡胶(NdBR)CB22和CB24在全钢巨型工程机械子午线轮胎胎侧胶中的应用。结果表明:与镍系顺丁橡胶相比,NdBR胶料具有较优的硫化平坦性,硫化胶具有较好的综合物理性能和耐屈挠性能及较低的压缩生热;CB22与CB24相比,CB22硫化胶具有较好的物理性能和较低的压缩生热,而CB24硫化胶具有较好的耐屈挠性能。     

国产工业化稀土顺丁橡胶的基本性能

对中国石油独山子石化公司工业化生产的稀土顺丁橡胶(NdBR)的基本性能进行了评价,并与进口NdBR及镍系顺丁橡胶(NiBR)进行了对比。结果表明,国产NdBR与炭黑的结合性好于NiBR,硫化速率稍快于进口NdBR及NiBR;力学性能、老化性能及动态力学性能均优于NiBR,与进口NdBR相当;滚动阻力低于NiBR。     

相对分子质量及其分布对稀土顺丁橡胶性能的影响

研究了5种不同相对分子质量及其分布的稀土顺丁橡胶(NdBR)的性能。结果表明,NdBR生胶和混炼胶的门尼黏度随相对分子质量的增加而升高;窄相对分子质量分布(多分散指数小于3.00)NdBR的生胶门尼黏度略高于与其相对分子质量相近而分布较宽的NdBR。相对分子质量对NdBR的正硫化时间影响不大,但最小转矩和最大转矩有随相对分子质量的增加而增大之趋势。生胶相对分子质量较低的NdBR,其硫化胶的300%定伸应力和拉伸强度较低,生热值较高,耐磨性能下降,滚动阻力升高。生胶门尼黏度为39~49的NdBR,其硫化胶的综合性能良好。填充适量操作油可以提高硫化胶的物理机械性能。窄相对分子质量分布NdBR硫化胶的300%定伸应力、拉伸强度、扯断伸长率、回弹性、永久变形、耐磨性以及滚动阻力等都优于相对分子质量相近而分布较宽的NdBR。     

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。