混炼条件对HAF填充型粉末SBR混炼性能的影响

采用Brabender转矩流变仪研究高耐磨炭黑 (HAF)填充型粉末SBR [P(SBR/HAF) ]和块状SBR (SBR/HAF)在较宽的混炼条件范围内 (转速 40～ 80r·min- 1 ,循环油温 5 0～ 10 0℃ )于密炼机中混炼的流变特性 ,讨论了混炼条件对胶料混炼流变性能的影响。结果表明 ,在试验的转子转速和循环油温范围内 ,P(SBR/HAF)比SBR/HAF表现出较高的表观剪切粘度 ,其对混炼时间的依赖性为SBR/HAF的 5 0 %～ 70 % ,但两者对转子转速和循环油温的敏感性相近     

P(SBR/NR/HAF)并用胶的性能

在SBR胶乳／NR胶乳共混的基础上，采用凝聚共沉法制备高耐磨炭黑（HAF）填充型粉末丁苯橡胶／天然橡胶并用胶[P(SBR/NR/HAF)]。研究了SBR／NR并用比、制备工艺等对P（SBR／NR／HAF）并用胶的混沌流变性能和物理机械性能的影响，并与块状SBR／NR／HAF并用胶进行了比较。研究表明，与SBR／NR／HAF相比，P（SBR／NR／HAF）的表观剪切粘度在SBR用量小于50份时对混炼时间的依赖性较低，而在SBR用量大于50份后对混炼时间具有更高的依赖性；P（SBR／NR／HAF)硫化胶 拉伸强度在整个并用范围内对SBR／NR并和比不敏感；采用胶乳预混合的工艺制备的P（SBR／NR／HAF）具有较好的物理机械性能。     

马来酸酐改性腰果壳油对丁苯橡胶性能的影响

以马来酸酐接枝共聚改性环氧基腰果壳油(M-CNSL)作为反应性增塑剂,研究M-CNSL用量对丁苯橡胶(SBR)硫化特性、物理性能和耐热空气老化性能的影响,并与芳烃油和未改性腰果壳油(CNSL)进行对比试验。结果表明:不同增塑剂对SBR的增塑作用从大到小依次为CNSL、芳烃油、M-CNSL,而其硫化胶的耐热空气老化性能没有明显差别;加入CNSL的SBR胶料焦烧时间和正硫化时间显著延长,硫化胶硬度、100%定伸应力较小,拉断伸长率较大;在0~25份用量范围内,添加CNSL或M-CNSL的硫化胶拉伸强度和撕裂强度均出现一个最大值,而添加芳烃油的硫化胶拉伸强度和撕裂强度随着增塑剂用量的增大而减小。硫化胶拉伸断面扫描电镜分析结果表明,M-CNSL的加入有利于白炭黑在胶料中的分散,起到了相容作用。     

炭黑填充型粉末天然橡胶的密炼机塑炼特性研究

采用实验室微型密炼机（Brabender转矩流变仪）研究了炭黑填充型粉末天然橡胶[P（NR/HAF）]的密炼机塑炼/混炼性能,即塑炼时间、塑炼温度和转速等基本工艺参数对胶料门尼粘度的影响。与传统的块状天然橡胶/炭黑（NR/HAF）的密炼机混炼相比,P（NR/HAF）在密炼机混炼时具有较高的混炼温升和较快的升温速率,使得胶料在较高的温度下被塑炼,从而表现出与传统的NR/HAF不同的密炼机混炼特性,其最佳塑炼温度有所降低。通过逐步回归分析建立的“门尼粘度-塑炼条件”模型可以较好地拟合和预测不同塑炼条件下P（NR/HAF）密炼机塑炼后胶料的门尼粘度。     

石墨烯/丁苯橡胶复合材料性能研究

以湿法制备的石墨烯/丁苯橡胶(SBR)母粒作为添加助剂,研究不同用量石墨烯/SBR母粒对SBR性能的影响。结果表明:添加少量湿法石墨烯/SBR母粒可以改善SBR胶料的加工性能;石墨烯的用量和分散性对胶料性能有明显影响,当石墨烯用量较小(0. 125份)时,石墨烯在胶料中的分散性较好,胶料的耐磨性能好,生热和滚动阻力低;石墨烯用量越大,胶料的抗切割性能越好。     

芳烃油在NBR及其并用胶胶料中的应用

芳烃油等量替代增塑剂DBP在NBR和NBR/SBR及NBR/CR胶料中的应用试验结果表明,采用芳烃油对胶料的性能无不良影响。芳烃油等量替代增塑剂DBP在NB胶管内层胶和NBR/SBR耐油胶板胶料中的实际应用试验结果表明,采用芳烃油有利于降低胶料成本。     

高耐磨炉黑填充型粉末丁腈橡胶硫化胶的老化性能

研究了高耐磨炉黑(HAF)填充型粉末丁腈橡胶[P(NBR/HAF)]硫化胶的热空气老化、耐异辛烷/甲苯溶剂及压缩永久变形性能,并与机械混炼的块状丁腈橡胶(BNBR)/HAF硫化胶进行比较。结果表明:P(NBR/HAF)硫化胶的耐热空气老化、耐溶剂及压缩永久变形性能受高分子树脂包覆剂及其用量的影响;P(NBR/HAF)硫化胶的上述性能达到或超过BNBR/HAF硫化胶。     

环保填充油对丁苯橡胶性能的影响

研究不同品种的环保填充油替代传统芳烃油(DAE)对丁苯橡胶(SBR)性能的影响。结果表明:不同填充油对胶料内部分子链产生多种作用,导致胶料结构与性能存在一定差异;DAE芳烃含量高、极性较强,填充SBR后胶料玻璃化温度提高,物理性能比填充环保芳烃油的胶料好,但生热较高;环保油填充胶料的性能与DAE填充胶料差别不大,可以通过优化橡胶制品配方消除差异。     

石墨烯/橡胶复合材料在输送带胶料中的应用

研究石墨烯/丁苯橡胶(SBR)复合材料或石墨烯/天然橡胶(NR)复合材料在输送带胶料中的应用。结果表明:添加石墨烯可以显著提高SBR胶料和NR/SBR胶料的300%定伸应力、拉伸强度、撕裂强度和耐磨性能;石墨烯/SBR复合母胶或石墨烯/NR复合母胶(石墨烯质量分数为0. 1)用量为10～15份时,胶料的加工安全性、物理性能、耐磨性能和耐热老化性能较好;添加少量石墨烯即可提高输送带胶料的抗撕裂性能和耐磨性能,有利于延长输送带的使用寿命。     

充国产环保油SBR的性能研究

对充国产环保油SBR的基本性能及其在胎面胶中的应用进行研究,考察国产环保油替代高芳烃油(DAE)和国外处理芳烃油(TDAE)的可行性.试验结果表明,充国产环保油的SBR胶料具有较好的加工性能、物理性能和动态性能,综合性能与充DAE的SBR和充TDAE的SBR胶料相当,某些性能略优;国产环保油可以替代DAE和TDAE作为填充油用于SBR.     

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。