RPA2000橡胶加工分析仪对SBR1723和SBR1712E性能的研究

使用RPA2000橡胶加工分析仪研究充环保油丁苯橡胶SBR1723和充芳烃油丁苯橡胶SBR1712E的基本性能及其轿车子午线轮胎胎面胶性能。结果表明,在基本性能研究中,与SBR1712E相比,SBR1723混炼胶加工性能稍差,硫化胶常规物理性能相近,生热和滚动阻力较低,牵引性和耐老化性较差。通过对补强体系的调整,SBR1723胎面胶与SBR1712E胎面胶性能差异变小,可以满足轿车子午线轮胎胎面胶性能要求。     

环保芳烃油对充油SBR性能的影响

通过对比SBR1723与SBR1712生胶与胶料性能,研究环保芳烃油(TDAE)对充油SBR性能及其在轿车子午线轮胎胎面胶中应用性能的影响.结果表明,由于填充油品不同,SBR1723玻璃化转变温度比SBR1712低2～3 ℃,其混炼胶加工性能稍差,硫化胶拉断伸长率下降,滚动阻力和生热降低,耐磨性较好,抗湿滑性能有所下降.在轿车子午线轮胎胎面胶中应用时,随着补强剂作用的加强,填充油品的影响变小,适当提高白炭黑用量可进一步降低滚动阻力和改善抗湿滑性能.     

SBR1721与SBR1712的性能对比研究

对SBR1721与SBR1712的性能进行了对比研究。结果表明，SBRl721与SBR1712相比，生胶和胶料的加工性能相近，硫化胶的硬度较高，拉伸强度、扯断伸长率较大，300％定伸应力和撕裂强度相当，抗湿滑性和操纵性较好，生热稍高，耐磨性较差。SBRl721是高速轿车子午线轮胎胎面胶理想的胶种。     

高性能子午线轮胎胎面胶的开发

采用充油SBR1721和低滞后炭黑DZ-13开发高性能子午线轮胎胎面胶配方,并试制185/60R14 82H轿车子午线轮胎。结果表明,试验配方胶料的基本物理性能与生产配方相差不大;损耗因子(tanδ)在40~100℃内较小,胶料的滚动阻力和生热降低,tanδ在-15~ 15℃内较大,胶料的抗冰滑和抗湿滑性能优异;试验轮胎在冰滑和湿滑路面上的抓着力较大,行驶时牵引力增大,制动距离明显缩短,同时滞后损失和生热降低,即轮胎的抗滑性能、滚动阻力和耐磨性能获得很好的平衡。     

低滚动阻力全钢载重子午线轮胎胎面胶配方的研究

研究低滚动阻力全钢载重子午线轮胎胎面胶的配方和性能。结果表明：主体材料采用天然橡胶（NR）/顺丁橡胶（BR）/溶聚丁苯橡胶（SSBR）并用,减小炭黑用量,增大高分散性白炭黑用量,胎面胶的混炼工艺和挤出工艺性能优良,耐磨性能明显提高,生热明显降低,抗湿滑性能提高,滚动阻力大幅下降;成品轮胎的耐久性能提升,滚动阻力降低。     

SBR1712在工程机械轮胎胎面胶中的应用

研究充油丁苯橡胶(SBR1712)替代非充油丁苯橡胶(SBR1502)在工程机械轮胎胎面胶中的应用。结果表明:采用SBR1712替代SBR1502,胶料的混炼排胶温度降低,混炼工艺性能和成型工艺性能良好,硬度、300%定伸应力和拉断伸长率基本不变,拉伸强度和撕裂强度稍有下降,但保持在较高的水平,阿克隆磨耗量和切割减量变化不大,压缩生热大幅降低;成品轮胎胎面胶的物理性能符合国家标准要求,轮胎的耐久性能明显提高。     

钕系顺丁橡胶在绿色轮胎胎面胶中的应用

研究钕系顺丁橡胶(Nd BR)在绿色轮胎胎面胶中的应用。结果表明:与未采用Nd BR的胎面胶相比,采用20份Nd BR的胎面胶门尼粘度较大,门尼焦烧时间较短;强伸性能相当或略差,耐热老化性能和耐磨性能提高,滚动阻力和生热降低。Nd BR有利于提高胎面胶耐磨性能及降低滚动阻力和生热,可作为绿色轮胎用原材料。     

高乙烯基聚丁二烯橡胶在高性能半钢子午线轮胎胎面胶中的应用

研究高乙烯基聚丁二烯橡胶(HVBR)等量部分替代溶聚丁苯橡胶(SSBR)或天然橡胶(NR)在高性能半钢子午线轮胎胎面胶中的应用。结果表明:HVBR等量部分替代NR用于轮胎胎面胶,其拉伸强度、撕裂强度、拉断伸长率、弹性和耐压缩疲劳性能均得以改善,但其耐磨性能、动态生热性能及滚动阻力性能均变差;HVBR等量部分替代SSBR用于轮胎胎面胶,可在保证高抗湿滑性能的同时,提高胶料的力学强度、硬度、耐压缩疲劳性能和耐磨性能,并降低动态生热、滚动阻力和密度,满足"绿色轮胎"的节能和高性能轮胎的性能要求。成品轮胎测试结果表明,相比于生产配方轮胎,采用HVBR等量部分替代SSBR胎面胶的轮胎耐磨性能略好,动力性能较好,滚动阻力、高速和耐久性能、干地操控性能和经济性相当。     

充油丁苯橡胶SBR1721实用配方的试验研究

充油丁苯橡胶SBR1721,其丁苯基础胶的结合苯乙烯含量为40%,100份胶中填充37.5份高芳烃油。SBR1721具有优异的抗湿滑性能,同时具有良好的加工性能,是制造高性能子午线轮胎胎面胶的理想材料。近几年,随着高性能子午线轮胎生产量的提高,国外SBR1721的用量在增加。齐鲁橡胶厂经过多年研究开发,成功进行了SBR1721的工业化试生产。本工作在完成对齐鲁橡胶厂开发的SBR1721样品的基本性能和加工性能试验之后,又对其进行了轮胎胎面胶和三角胶的实用配方试验研究。一、轿车子午线轮胎胎面胶1.试验配方胎面胶试验配方为:SBR172170.0;SBR71226.…     

橡胶材料的技术发展及应用(二)

(续上期)2.2.1聚丁二烯橡胶在轮胎中的应用现代合成橡胶的应用,使满足人们在安全、经济、环保方面对轮胎越来越严格的要求成为可能。轿车轮胎和载重轮胎的胎面胶料,必须尽可能使滚动阻力、耐磨性能、抗湿滑性能这一魔幻三角得到最佳的平衡,而这三种性能是互相矛盾的,很难做到同时使这三种特性得到改善。高顺式聚丁二烯橡胶不仅可克服上述魔幻三角的第三边,即耐磨性能问题,还可在轮胎的其它部位发挥其优越性。2.2.1.1胎面胶载重轮胎胎面胶通常以天然橡胶为主。其胎面胶具有良好的耐磨性能、抓着性能、耐生热性能和低滚动阻力等综合平衡性能。…     

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。