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1.
扫描探针对炭黑结构及其结合胶微观形貌的研究   总被引:1,自引:0,他引:1  
以N234、N330、低滞后DZ13 3种不同结构的橡胶补强炭黑为材料,通过扫描探针对其聚集体形貌及其结合胶的微观形貌进行了研究。实验表明:N234的聚集体小,分布窄,二次结构影响较小;N330的聚集体形貌如同葡萄串,有链枝状;DZ13的聚集体分布较宽,大小不一。通过对结合橡胶结构观察发现,N234的结合方式不同于其它2种结构炭黑,结合胶的量更大,而DZ13表面的橡胶壳大于N330表面的橡胶壳,侧面证明了DZ13的表面活性较大。结合胶形貌的研究有助于了解炭黑结构对橡胶补强的影响,对炭黑补强机理的研究提供了直观的证据。  相似文献   

2.
陈林东 《橡胶科技》2019,17(5):0287-0291
研究高岭土与炭黑N660、沉淀法白炭黑对天然橡胶(NR)补强性能的差异,并考察高岭土部分替代炭黑N660在子午线轮胎气密层胶中的应用。结果表明,高岭土对NR的补强作用优于未加偶联剂的沉淀法白炭黑,接近炭黑N660,其中改性高岭土对NR的补强效果优于普通高岭土;采用少量高岭土尤其是改性高岭土等量部分替代炭黑N660,气密层胶料拉伸强度提高,加工性能和其他物理性能变化不大。在橡胶配方中用高岭土部分替代炭黑具有可行性,可降低原材料成本,同时节能降耗。  相似文献   

3.
研究超细复合矿物无机填料替代炭黑或白炭黑在输送带胶料中的应用。结果表明,在丁苯橡胶(SBR)和天然橡胶(NR)/顺丁橡胶(BR)/再生橡胶输送带覆盖胶中超细复合矿物无机填料替代炭黑N330的比例分别不超过20%和30%,在NR/SBR/再生橡胶织物芯输送带贴胶中超细复合矿物无机填料替代炭黑N660的比例不超过10%,在NR/SBR/BR钢丝绳芯输送带粘合胶中超细复合矿物无机填料替代白炭黑的比例可以达到30%~50%。  相似文献   

4.
李长继 《轮胎工业》2007,27(10):602-606
用断裂力学方法研究炭黑N330、炭黑N330/白炭黑和白炭黑补强NR硫化胶的疲劳破坏特性.结果表明,与炭黑N330和炭黑N330/白炭黑补强的NR硫化胶相比,白炭黑补强的NR硫化胶疲劳寿命较长,内部潜在缺陷较少,抗裂纹扩展性能较好;随着疲劳时间的延长,NR硫化胶拉断时的应变能密度减小;疲劳寿命方程能够快速、准确地预测NR硫化胶的疲劳寿命.  相似文献   

5.
在26.5R25翻新工程机械轮胎胎面胶配方中添加炭黑和白炭黑,研究其对胎面胶的补强效果。结果表明:单一品种炭黑补强胎面胶时,炭黑N151用量为40份时补强效果较佳;炭黑N330与其他品种炭黑并用补强胎面胶时,炭黑N330用量为40份、其他品种炭黑用量为20份时补强效果较佳;炭黑N330与白炭黑并用补强胎面胶时,炭黑N330用量为40份、白炭黑用量为20份时补强效果较为理想,胎面胶的耐磨性能和抗崩花掉块性能均提高;炭黑补强胎面胶机理可应用分子链滑动理论解释,胎面胶中炭黑含量有最佳值,橡胶分子链与炭黑颗粒之间的有效融合吸附阻止了橡胶分子链发生形变和拉伸,从而对橡胶起到补强作用。  相似文献   

6.
炭黑并用对NR/ENR共混胶力学性能及减震性能的影响   总被引:3,自引:0,他引:3  
对比N660研究了N330/N660、N660/N990炭黑填充体系对天然橡胶(NR)/环氧化天然橡胶(ENR)共混胶力学性能、压缩疲劳生热性能及减震性能的影响,并采用橡胶加工分析仪(RPA)对其加工性能进行了分析。结果表明:N660/N330和N660/N990两种填充体系硫化胶的力学性能,基本上是单用一种炭黑所得硫化胶力学性能的加权平均;不同粒径炭黑并用均能使共混胶的贮能模量E′下降,并且有利于拓宽NR/ENR减震材料的减震范围;不同粒径炭黑并用有利于改善NR/ENR共混胶料的加工性能。  相似文献   

7.
以天然胶(NR)乳为原料,稀土化合物改性高耐磨炭黑N330(N330-Re)为填充隔离剂,用凝聚共沉法制备了稀土掺杂高耐磨炭黑填充型粉末NR[P(NR/N330-Re)],研究了炭黑乳化剂用量、粉末化温度、硫磺用量、稀土元素的种类及用量、过渡金属Zn的用量、N330-Re的用量等因素对其硫化胶物理机械性能的影响.结果表明,所选用的稀土化合物对高耐磨炭黑N330具有优良的改性效果,从而对P(NR/N330-Re)硫化胶有显著的补强作用,其中以Sm2O3与La2O3改性效果最佳.  相似文献   

8.
白炭黑与NR的相互作用研究   总被引:3,自引:2,他引:1  
研究白炭黑与NR的相互作用.结果表明,白炭黑补强NR结合橡胶中白炭黑-NR化学作用占优势;随着白炭黑表面羟基含量的增大,胶料中结合橡胶总质量分数(wBt)和化学结合橡胶质量分数(wBc)呈单调增大趋势,物理结合橡胶质量分数(wBp)变化不大;与炭黑补强NR相比,白炭黑补强NR的wBt和wBc均较大,化学结合橡胶在二甲苯中全部离解的温度高100 ℃左右,化学键强度较高;白炭黑补强NR硫化胶中化学作用占优势,对强度的贡献占主要地位,并随着白炭黑表面羟基含量的增大先减小后增大,物理作用变化趋势则相反.  相似文献   

9.
研究普通高岭土和改性高岭土对天然橡胶(NR)的补强性能,并与炭黑N660、白炭黑和纳米碳酸钙对比。结果表明,炭黑N660对NR胶料的补强效果最佳,改性高岭土次之,普通高岭土略逊于白炭黑,但优于纳米碳酸钙。  相似文献   

10.
谢斌 《轮胎工业》2013,33(3):169-174
研究炭黑品种和用量对轮胎胎侧胶黑度的影响。结果表明:在胎侧胶的常用炭黑中,当炭黑用量相同时,黑度大小顺序依次为:N375,N326,N330,N660;在全天然橡胶(NR)或NR/顺丁橡胶(50/50)配方中,当炭黑用量为46份时,胎侧胶的黑度达到最大值;通过调整生产配方,在保证性能的同时可以提高胎侧胶的黑度。  相似文献   

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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.  相似文献   

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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.  相似文献   

17.
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.  相似文献   

18.
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.  相似文献   

19.
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.  相似文献   

20.
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。  相似文献   

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