终炼胶变转速混炼工艺研究

研究终炼胶的变转速混炼工艺。结果表明,相对于低速恒转速终炼工艺,采用高速变转速终炼工艺制备的胶料能够满足生产工艺要求,对混炼胶的加工性能和硫化胶的物理性能无明显影响。胶料中的硫黄分散更加均匀,终炼效率提升16.9%。     

XMY-85密炼机试制成功

四川亚西机器厂在参照国内外密炼机最新技术的基础上,设计了XMY-85密炼机。由于该机采用啮合型转子,其胶料混合速度快,混炼时间短,生产能力强。该机还具有混炼胶料分散性好、炼胶温度低、能进行橡塑共炼等特点。该机主要用于胶料和塑料的     

改变胶料取样方法保证快检质量

改变胶料取样方法保证快检质量炼胶是橡胶制品生产中的一个重要工艺过程，而胶料质量的好坏对保证下一道工序的顺利进行和半成品、成品的性能都起着重要作用。通常胶料快检取样的方法是胶料炼好下片时从辊筒中间割下一小片胶，趁热折叠起来后用手把双层胶片压合，供快检人...     

SSM法和传统炼胶工艺生产的胎侧胶料性能对比

通过对传统法炼胶工艺与SSM法炼胶工艺对胶料性能的影响进行相关对比分析可以看出,用SSM法炼胶工艺生产的胎侧胶料的定伸应力、拉伸强度、拉断伸长率、炭黑分散度等级均较优;SSM法炼胶工艺生产的胎侧胶料快检检测结果的稳定性更高,车次与车次间均匀性明显提高。成品轮胎的胎侧稳定性能由此得到提升,提高了成品轮胎的市场竞争力。     

内胎胶配方及混炼工艺优化

通过增大精细再生胶用量、调整生胶体系和补强体系优化内胎胶配方,并通过提高一段混炼排胶温度及将二段开炼改为密炼优化胶料混炼工艺。结果表明,与生产配方相比,采用优化混炼工艺的优化配方胶料拉伸强度、拉断伸长率、撕裂强度以及耐热老化性能提高,工艺性能良好,成品内胎性能改善,胶料成本降低0．48元·kg^-1。     

浅谈炼胶设备的性能与操作对炼胶质量的影响

从胶料的塑炼和混炼两个方面，简要分析了炼胶设备的性能与操作对炼胶质量的影响，对实际操作具有一定的参考价值。     

SSM法和传统炼胶工艺生产的粘合胶料性能对比

较传统炼胶工艺,SSM一次法炼胶工艺生产的粘合胶料在门尼黏度、焦烧性能、流变、定伸应力、拉伸强度、拉断伸长率、回弹性、炭黑分散度等方面均较优,生产的钢丝带束层粘合胶料快检数据的稳定性更高。钢丝带束层粘合胶料的加工性能由此得到提升,覆胶后表面光滑,成品轮胎质量得到保证,提高了成品轮胎的市场竞争力。     

胶料流动性分析仪问世

特拓(青岛)轮胎技术有限公司日前成功研制出胶料流动性分析仪,并在用户中获得运用,终结了我国橡胶工业长期以来依靠检测门尼黏度判断胶料加工性能的历史。胶料流动性分析仪能在高剪切下准确检测胶料流动性,更真实地反映胶料实际生产过程中的加工性能,填补了母胶快速检测的空白。该检测仪适用于所有制品的母胶和终炼胶,能够灵敏地检测出普通配方以及白炭黑配方胶料原材料和工艺的波动。     

新型塑解剂Z-230在NR胶料中的应用

研究新型塑解剂Z-230在NR胶料中的应用效果。试验结果表明，应用塑解剂Z-230，可有效降低NR塑炼胶的门尼粘度，增大塑炼胶的塑性，缩短塑炼时间，减小密炼机能耗，对NR胶料硫化特性、硫化胶物理性能及轮胎成品性能无不利影响。     

使用串联密炼机一次法低温混炼工艺生产PCR胎面胶

白炭黑是实现绿色轮胎生产的关键材料,而传统炼胶方式对于高填充白炭黑的胶料混炼是非常困难的。为更好地解决白炭黑混炼的工艺难题,采用串联式密炼机一次法低温混炼工艺。研究得出,串联式密炼机与传统的密炼机混炼工艺相比具有更为优异的炼胶性能,胶料混炼能耗降低,生产效率提高,胶料质量更加稳定。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.     

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.