首页 | 本学科首页   官方微博 | 高级检索  
相似文献
 共查询到20条相似文献,搜索用时 46 毫秒
1.
介绍了以杂氮硅三环化合物、含双酚A骨架的烷氧基硅烷及N-β-氨乙基-γ-氨丙基三甲氧基硅烷与六甲基二硅氮烷的加热混合物为增粘剂配制的脱醇型单组分室温硫化(RTV-1)硅橡胶密封剂,以及具有粘接耐久性的脱醇型RTV-1硅橡胶密封剂的配制。  相似文献   

2.
单组分室温硫化硅橡胶的配制(八)   总被引:3,自引:2,他引:1  
黄文润 《有机硅材料》2003,17(5):32-37,39
介绍了改进脱醇型单组分室温硫化(RTV-1)硅橡胶贮存稳定性的方法(包括采用六甲基二硅氮烷、三烷基硅酸酯、烷氧基硅酸酯、异氰酸根合烃基烷氧基硅烷、氯化钙、氯化镁作醇清除剂及选择适当的钛酸酯作催化剂)和采用双螺杆挤出机配制脱醇型RTV-1硅橡胶的方法。  相似文献   

3.
单组分室温硫化硅橡胶的配制(十四)   总被引:2,自引:2,他引:0  
介绍了脱丙酮型单组分室温硫化(RTV-1)硅橡胶的特点,以及低挥发性、抗黄变性、耐油性和低模量脱丙酮型RTV-1硅橡胶的配制.  相似文献   

4.
单组分室温硫化硅橡胶的配制(四)   总被引:2,自引:5,他引:2  
介绍了低拉丝性、防污性及防霉性脱酮肟型单组分RTV硅橡胶密封剂的配制方法,分别讨论了密封剂配制工艺及添加含咪唑啉基的聚有机硅氧烷,高吸油材料、硅橡胶微粉,疏硅氧烷剂、三唑基化合物对脱酮肟型单组分硅橡胶密封剂性能的影响。  相似文献   

5.
介绍了脱酰胺、脱羟胺型单组分室温硫化(RTV-1)硅橡胶的特点,以及脱酰胺/羟胺型(包括普通型、高粘接性型、耐水性型、超低模量型)、脱羟胺型(包括用含S-H基的硅氧烷或异氰酸酯作羟胺清除剂)、脱酰胺型(快干型、自流平型)及脱酰胺/酮肟型低模量RTV-1硅橡胶的配制。  相似文献   

6.
介绍了电子、电气用脱醇型单组分室温硫化(RTV-1)硅橡胶及耐热性、导热性、阻燃性、能粘聚烯烃塑料的脱醇型RTV-1硅橡胶的配制。  相似文献   

7.
耐热阻燃硅橡胶的研制   总被引:4,自引:1,他引:4  
曲艳斌  方辉 《有机硅材料》2006,20(3):111-113
以107硅橡胶为基胶、白炭黑为补强填料、Fe2O3为耐热添加剂、硅氮烷为羟基清除剂、氢氧化镁和十溴联苯醚为阻燃剂,配制了脱酮肟型单组分室温硫化(RTV-1)硅橡胶;讨论了耐热添加剂用量、白炭黑表面处理与否以及羟基清除剂使用与否对RTV硅橡胶耐热性的影响,并测试了硅橡胶的阻燃性能。结果表明,RTV-1硅橡胶中加入表面经硅烷偶联剂处理的氧化铁红后,其耐热性大增;当氧化铁红的用量为10份时,RTV-1硅橡胶经260℃×24h热老化后,其拉伸强度、扯断伸长率及硬度的变化率均小于10%;使用经六甲在二硅氮烷表面处理的沉淀法白炭黑作补强填料、硅氮烷作羟基清除剂,也有利于提高硅橡校的耐热性;使用氢氧化镁和十溴联苯醚的复配阻燃剂,能有效提高硅橡胶的阻燃性,使硅橡胶的阻燃性达到FV-0级。  相似文献   

8.
通过添加无水甲醇模拟脱醇型单组分室温硫化(RTV-1)硅橡胶生产过程中产生的甲醇,研究了甲醇对脱醇型RTV-1硅橡胶性能的影响。结果表明:在配制脱醇型RTV-1硅橡胶时,甲醇的加入对密封胶力学和粘接性能无影响,但会影响部分施工性能。经70℃加速贮存5天后(相当于室温放置6个月),甲醇的存在会导致表干时间延长,力学强度和粘接性能均有一定幅度的下降;当甲醇质量分数为1%时,脱醇型RTV-1硅橡胶不硫化;若控制配制时甲醇的残留质量分数低于0.25%,则在加速贮存后,脱醇型RTV-1硅橡胶的施工性能略有下降,力学性能与粘接性能保持率达到80%以上。  相似文献   

9.
以黏度500~10 000 mPa·s的端羟基聚二甲基硅氧烷(107硅橡胶)为基础聚合物、超细白炭黑和其它粉料为填料,经过加热脱水处理后添加脱醇型交联剂、催化剂和助剂,配制成脱醇型单组分室温硫化(RTV-1)硅橡胶;再添加惰性硅油,制得系列渗油性低黏度RTV-1硅橡胶。考察了107硅橡胶的黏度,惰性硅油的黏度、用量、环境温度对RTV-1硅橡胶渗出性的影响,同时研究了惰性硅油的渗出性对输电线抗结冰性能的影响。结果表明。随着107硅橡胶黏度的减小、惰性硅油黏度的增加,惰性硅油用量的增多、环境温度的升高,RTV-1硅橡胶的渗油性增大,最后达到平衡;其质量损失越小,反之越大;聚二甲基硅氧烷的黏度越大、所占比例越大,渗油量越多、渗油速度也越快;其质量损失越大,且达到平衡所需时间越长;渗油性越好的RTV-1硅橡胶,其抗结冰性能好。  相似文献   

10.
介绍了防霉性、耐浸水及耐粘接性、低臭味性、无毒性脱酸型单组分室温硫化硅橡胶密封剂的配制,以及改进脱醋酸型单组分RTV硅橡胶密封粘接性的方法。  相似文献   

11.
12.
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   

13.
14.
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   

15.
16.
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   

设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号