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1.
纳米白炭黑对NBR性能的影响   总被引:1,自引:0,他引:1  
杨凤香  王鲁鑫  孟莲香  尚波 《橡胶工业》2005,52(10):601-604
试验研究表面改性剂品种及其用量、纳米白炭黑粒径及其用量以及纳米白炭黑/炭黑并用比对NBR硫化胶物理性能的影响。结果表明,表面改性剂对纳米白炭黑填充NBR硫化胶物理性能的影响程度大小顺序为硅烷偶联剂KH-550、钛酸酯偶联剂NDZ-201、表面活性剂ABS。用0.6份硅烷偶联剂KH~550对纳米白炭黑进行改性后,当纳米白炭黑粒径为5~15nm(用量为30份);纳米白炭黑用量为50份(粒径为15~25nm);纳米白炭黑/炭黑并用比为15/35(纳米白炭黑粒径为15~25nm)时,NBR硫化胶的综合物理性能最佳。  相似文献   

2.
偶联剂改性填充剂在橡胶中的应用   总被引:7,自引:0,他引:7  
比较不同种类偶联剂改性白炭黑和碳酸钙对胶料性能的影响及偶联剂用量对胶料物性的影响。结果表明:偶联剂Si-69对白炭黑的改性效果比钛酸酯偶联剂改性效果优越;偶联剂改性碳酸钙填充硫化胶的性能与未填充碳酸钙胶料的性能接近,并提高产品性价比,偶联剂Si-69在胶料中的用量以无机填料用量的4%-6%左右效果较好。  相似文献   

3.
雷云霄  王稚阳 《橡胶工业》2018,65(4):389-393
天然橡胶(NR)与丁腈橡胶(NBR)共混,共混胶兼并NR物理机械性能及NBR耐油性能,但炭黑补强/NR/NBR橡胶复合材料物理机械性能相比炭黑补强NR橡胶复合材料差。在炭黑补强/NR/NBR橡胶复合材料中,加入碳酸钙晶须旨在增强复合材料物理机械性能,提高其使用范围。本文采用钛酸酯偶联剂对碳酸钙晶须进行改性,研究改性后碳酸钙晶须对炭黑/ NR/ NBR橡胶复合材料性能的影响。结果表明:钛酸酯偶联剂改性后的碳酸钙晶须,表面性能改变,有效提高了碳酸钙晶须与炭黑/NR/NBR橡胶复合材料的相容性。当碳酸钙晶须用量为4份时,复合材料的综合性能最佳,有效改善复合材料Payne效应。  相似文献   

4.
研究偶联剂Si69和KH-550与混炼工艺对炭黑填充NBR胶料硫化特性、表观交联密度、物理性能和动态性能的影响。结果表明,偶联剂的加入能够延长胶料的t90,经高温混炼后的NBR胶料的焦烧时间缩短,t90延长;偶联剂能够增大NBR胶料的表观交联密度和炭黑-橡胶间的相互作用,经高温混炼后作用更加明显,硫化胶的物理性能提高;加入偶联剂KH-550并经高温辊改性后的NBR硫化胶具有更好的耐热老化性能。偶联剂Si69或KH-550能够改善NBR硫化胶的动态性能,加入偶联剂KH-550并经高温改性后性能较佳。  相似文献   

5.
新型偶联剂对橡胶力学性能的影响   总被引:1,自引:0,他引:1  
谢富霞  李佣军 《弹性体》1996,6(2):30-33
本文讨论了新型偶联剂用量对陶土填充橡胶与炭黑填充橡胶动态性能与力学性能的影响.并且用红外光谱对偶联剂改性陶土表面进行了表征。结果表明:该偶联剂明显提高硫化胶的动态性能、撕裂强度及陶土填充橡胶的拉伸强度,其用量超过1.5重量份对硫化胶的力学性能有不良影响。  相似文献   

6.
采用机械共混法制备凹凸棒土(AT)/丁腈橡胶(NBR)纳米复合材料,研究了AT用量、偶联剂种类对复合材料硫化特性和力学性能的影响,并用透射电镜(TEM)和扫描电镜(SEM)观察了AT及其纳米复合材料的微观结构。结果表明,在机械剪切力的作用下,AT分离并分散在NBR中,形成纳米复合材料。随着AT用量的增加,AT/NBR的t10和t90缩短,硫化速度提高,硬度、拉伸强度、定伸应力和撕裂强度先增大后逐渐减小或不变;当AT用量为40份时,综合性能最好。偶联剂用量相同时,Si69改性效果最好,制得的AT/NBR综合力学性能与白炭黑、炭黑填充NBR性能相近。  相似文献   

7.
偶联剂Si69改性白炭黑对NR/SSBR并用胶性能的影响   总被引:1,自引:1,他引:0  
程利  牟守勇  赵树高  张萍 《橡胶工业》2009,56(3):149-153
试验研究偶联剂Si69用量和白炭黑改性方法对白炭黑填充NR/SSBR并用胶性能的影响.结果表明,当采用直接加入法改性白炭黑时,随着偶联剂Si69用量的增大,Payne效应减弱,NR/SSBR并用胶的t10延长,t90缩短,硫化胶的物理性能提高,偶联剂Si69用量以4 5份为宜.与直接加入法改性白炭黑填充并用胶相比,预处理法改性白炭黑填充并用胶的Payne效应减弱,拉伸强度和撕裂强度增大;高温静置处理法改性白炭黑填充并用胶的定伸应力、拉伸强度和损耗模量增大.  相似文献   

8.
改性纳米氮化硅/NBR复合材料的性能   总被引:5,自引:0,他引:5  
采用大分子偶联剂改性纳米氮化硅,研究改性纳米氮化硅用量对改性纳米氮化硅/NBR复合材料性能的影响.结果表明,对纳米氮化硅进行改性可以改善其在NBR基体中的分散性;采用少量(0.5~1.5份)改性纳米氮化硅填充NBR可以提高复合材料的物理性能和动态力学性能,并大幅延长相应油封制品的使用寿命.  相似文献   

9.
甲基丙烯酸原位改性纳米碳酸钙增强丁苯橡胶   总被引:2,自引:0,他引:2  
用甲基丙烯酸(MAA)原位改性纳米碳酸钙增强丁苯橡胶(SBR),考察了过氧化二异丙苯(DCP)、纳米碳酸钙用量对SBR混炼胶硫化特性及硫化胶力学性能的影响,分析了纳米碳酸钙填料与SBR橡胶基体之间的相互作用。结果表明,适量地加入DCP和MAA原位改性纳米碳酸钙,可降低SBR混炼胶的硫化速率;当改性纳米碳酸钙用量为80份、DCP用量为1.0份时,SBR硫化胶的拉伸强度达到12.8MPa,扯断伸长率为620%;MAA可使纳米碳酸钙与SBR基体之间的作用力明显增强。  相似文献   

10.
纳米碳酸钙在二烯类橡胶中的应用   总被引:1,自引:0,他引:1  
朱寅  万超瑛  张勇  张隐西 《橡胶工业》2005,52(3):184-188
综述纳米碳酸钙在二烯类橡胶中的应用研究进展及其在轮胎中的应用情况。改性纳米碳酸钙可明显改善NR硫化胶性能;单独填充EPDM所得胶料强度很低,与高耐磨炉黑并用填充对EPDM补强效果较佳;填充NBR可提高胶料耐油性能;在轮胎中主要应用于帘布胶、内层胶、内胎胶、垫带胶和白胎侧胶。  相似文献   

11.
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.  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   

14.
建立了测定地球化学样品中包括As、Cr、Ge、V等18种微量、痕量元素的ICP-MS方法。地化试样用HF-HNO3混酸分解后,以1 1 HNO3溶解干渣。由于制样不使用盐酸,避免了Cl对As、Cr、Ge、V的质谱干扰。用国家一级地球化学标准物质GBW 07309制备溶液优化仪器工作参数,并用于校准。方法测定限(6s)为:0.007~6.4μg/g,精密度(RSD%,n=12)为:29%~9.4%,经过国家一级地球化学标准物质的分析验证,结果与标准值吻合。方法已应用于国土资源调查的试样分析。  相似文献   

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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   

20.
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   

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