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1.
李茂果  姚伟  古忠云  赵祺 《粘接》2001,22(3):16-18
介绍了一种新的压敏胶转移方法--湿法转移技术。研究了橡胶溶剂和丙烯酸酯乳液型压敏胶对橡胶泡沫切片的湿法转移施胶工艺;对转移后胶层与基材的附着力进行了试验。研究表明,湿法转移技术可以较好地解决压敏胶干式转移中存在的附着力、转移困难及起泡等问题。  相似文献   

2.
为探索硼铝复合粉在热固PBX中的应用,以HMX为基,加入氧化剂高氯酸铵(AP)、硼铝复合粉和聚氨酯黏结剂,设计和制备了6种配方的含硼铝炸药;分别制备3种带壳体及3种不带壳体的Φ50mm含硼铝炸药柱;用弹簧探针法测试了无壳体药柱和带壳体药柱的爆速,分别用经验公式和相对凹坑深度法计算了爆压,讨论了硼铝复合粉含量对其爆轰性能的影响。结果表明,炸药GH-4、GH-5和GH-6用手工浇注成型,Φ50mm×150mm炸药柱密度在1.530~1.570g/cm3之间,爆速在6.900~7.400mm/μs之间,爆压约19GPa,适用于含硼铝炸药配方筛选;炸药PF-1、PF-2和PF-3用真空振动浇注成型,Φ50mm×110mm炸药柱密度约1.693g/cm3,爆速在7.800~8.000mm/μs之间,爆压约24GPa。炸药PF-3中含质量分数20%、硼铝质量比1∶1的复合粉,含金属炸药的组合效应使少量硼铝复合粉在反应区参加反应,其爆速和爆压值较其他配方高,表明弹簧探针法可作为炸药爆速测试的一种补充电测法,在无法实施铜箔探针法的情况下,可以考虑用弹簧探针法。  相似文献   

3.
影响压敏胶粘带180°剥离强度因素的研究   总被引:2,自引:0,他引:2  
本文探讨了试验板表面的粗糙度、温湿度、基材、试验板的放置时间及胶层厚度对压敏胶粘带 1 80°剥离强度的影响。实验结果表明 ,与溶剂型丙烯酸酯压敏胶相比 ,乳液型丙烯酸酯压敏胶对试验板的表面粗糙度更为敏感 ;试验板粘贴胶带后的放置时间对橡胶型胶带影响较大 ,而对丙烯酸酯型压敏胶的影响小 ;温湿度对 1 80°剥离强度也有很大影响 ;基材厚度相同时 ,胶在PET膜上的剥离强度比在OPP膜上的剥离强度大 ;随着PET厚度从 1 2 μm增大到 3 8μm ,剥离强度从 2 73N/cm上升至 4 2 9N/cm ;在OPP膜上 ,胶层从 1 0 μm增至 4 0 μm时 ,1 80°剥离强度从 2 2 3N/cm上升至 3 81N/cm  相似文献   

4.
MQ硅树脂改性丙烯酸酯压敏胶的研究   总被引:1,自引:0,他引:1  
采用溶液聚合法将含有乙烯基的MQ硅树脂共聚到丙烯酸酯链节之中,合成了硅树脂改性丙烯酸酯压敏胶。利用FT-IR对改性后的压敏胶进行结构表征,确定了硅树脂的加入时间和最佳用量。结果表明,在聚合反应先期或中期加入10%的硅树脂,制得的压敏胶性能优异。改性丙烯酸酯压敏胶在150℃下持粘性为2200s,室温180°剥离强度为14.5N/25mm,100℃的180°剥离强度为6.3N/25mm,在200℃热老化10h后,剥离强度仍达6.2N/25mm。  相似文献   

5.
为了分析由聚能射流引起的两种典型屏蔽压装PBX炸药的冲击起爆感度,采用某Ф80mm制式破甲弹作为标准射流源,在炸高为150mm的条件下,对不同厚度45~#钢覆盖板屏蔽的PBX-1和PBX-2炸药进行了射流冲击起爆感度试验;采用"兰利法"对覆盖板的厚度进行选取,得到了聚能射流引爆两种典型压装PBX炸药的临界隔板厚度。结果表明,临界爆轰时,PBX-1炸药覆盖板厚度为35~40mm,PBX-2炸药覆盖板厚度为140~150mm,即PBX-1的临界隔板厚度比PBX-2炸药减少73.3%;PBX-1炸药起爆所需的射流能量为185mm~3/μs~2,远高于PBX-2炸药,因此PBX-1炸药的射流安全性显著优于PBX-2炸药。  相似文献   

6.
室温固化丙烯酸胶粘剂NationalstarchandchemicalInvestmentHoldingCorp.,EP561352(1993.9.22),11页。胶粘剂2个组分,A组分含丁苯嵌段共聚橡胶(Ⅰ)25,甲基丙烯酸异冰片酯6O,甲基丙烯酸2-乙基已酯(Ⅱ)15,(C2H5)3B-H2N-(CH2)3NH2络合物1份;B组分含Ⅰ25,甲基丙烯酸四氢糠酯50,Ⅱ20,甲基丙烯酸2-羟丙酯5,异丙苯过氧化氢1,宋甲醛(活化剂)1份。A与B约等量混合,凝胶时间32分钟。胶具有良好粘接性能。导热和电绝缘的压敏胶MinnesotaMin.lugandMfgcoEP566093(199310ZO),12页。压敏胶主体是丙烯酸一丙烯酸…  相似文献   

7.
将含有乙烯基的硅树脂利用溶液聚合法将其引入到丙烯酸酯分子链中,合成了有机硅树脂改性丙烯酸酯压敏胶。利用红外光谱对改性后的压敏胶进行了结构表征。对改性前后压敏胶的耐高低温冲击等性能、耐热老化性能及耐湿热老化性能进行比较,得出改性后的压敏胶性能优越。60℃下湿热老化1000h后改性压敏胶180°室温剥离强度为5.68N/25mm。对丙烯酸酯压敏胶、有机硅压敏胶、有机硅改性丙烯酸酯压敏胶的室温、高温性能及高低温冲击性能进行了比较,经高低温冲击后,丙烯酸酯压敏胶失去压敏性能,而硅树脂改性的丙烯酸酯压敏胶还具有一定的剥离强度,为10.32 N/25mm。  相似文献   

8.
用圆筒试验研究了Φ25 mm和Φ50 mm含铝炸药的JWL状态方程,采用解析求解和二维数值模拟,得到了两种含铝炸药的JWL状态方程参数.结果表明,压装含铝炸药的后加速能力较强.含铝炸药的加速能力与JWL状态方程参数与尺寸有关.  相似文献   

9.
将环氧有机硅固化剂9301以及异氰酸固化剂2102加入到增黏丙烯酸酯乳液中,成功制备出耐高温丙烯酸酯压敏胶。研究压敏胶的固化行为,探讨固化剂的种类和用量对压敏胶粘接性能及耐温性的影响。结果表明:固化剂与复合物发生了交联反应,9301和2102固化体系的适宜固化条件分别为150℃/5min和110℃/3min。随着固化剂用量增加,压敏胶的凝胶率和玻璃化转变温度提高,剥离时由内聚破坏转变为界面破坏,初黏力与剥离强度降低,耐高温性能得到改善。当9301与2102用量为2wt%时,压敏胶的剥离强度分别为11.6N/25mm与10.2N/25mm,可耐180℃高温。  相似文献   

10.
以丙烯酸异辛酯、丙烯酸丁酯、丙烯酸羟基乙酯、丙烯酸羟基丙酯、GMA(甲基丙烯酸缩水甘油酯)和丙烯酸异冰片酯为共聚单体,BPO(过氧化二苯甲酰)为引发剂,NDM(正十二烷基硫醇)为链转移剂,采用本体聚合、两步法合成工艺(自由基聚合+逐步聚合)制备常温下低黏度、无溶剂的聚丙烯酸酯压敏胶,分别探讨了链转移剂正十二烷基硫醇含量、催化剂选择、功能单体ACMO(丙烯酰吗啉)加入量、胶层厚度和光引发剂配比对压敏胶性能的影响,以及压敏胶的耐高温性能。研究结果表明:当w(NDM)=1%、w(ACMO)=8%(相对预聚物总量而言)、催化剂选择对甲苯磺酸、胶层厚度为50μm时,压敏胶的环形初粘力达到30 N·(25 mm)~(-1),180°剥离强度为32 N·(25 mm)~(-1),持粘时间72 h。而且压敏胶有较好耐高温性,经历150℃、12 h的放置后,压敏胶180°剥离强度和持粘时间没有下降。  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   

13.
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   

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15.
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   

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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   

19.
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   

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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