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1.
空心玻璃微珠复合聚氨酯泡沫塑料的泡孔结构与性能   总被引:12,自引:3,他引:12  
研究了加入空心玻璃微珠后,硬质聚氨酯泡沫塑料的泡孔结构、压缩性能以及阻尼性能。结果表明,随着空心玻璃微珠用量的增加,硬质聚氨酯泡沫塑料的泡孔减小,压缩强度提高,而材料的阻尼因子无明显变化。  相似文献   

2.
《聚氨酯》2008,(2):32-34
聚氨酯硬质泡沫塑料是一种性能优良的绝热材料和结构材料。在聚氦酯各类制品中,产量仅次于软质泡沫塑料。它是一种高度交联的热固性材料,泡孔结构大部分是闭孔型,少量开孔结构硬泡用于特殊场合。  相似文献   

3.
泡沫塑料是塑料材料中的一个大类,根据不同的原料和配方,可制成硬质、半硬质和软质泡沫塑料,广泛应用于各个领域。不同用途的泡沫塑料有不同的泡孔结构要求,所谓泡孔结构是指泡沫体中的闭孔率(即闭孔的体积百分数)、或开孔率(即开孔的体积  相似文献   

4.
三、聚氨酯泡沫塑料制品 (三)硬质聚氨酯泡沫塑料硬质聚氨酯泡沫塑料(简称硬质泡沫或硬泡),具有绝热效果好、比强度大、成型工艺简单等特点。广泛地用作绝热保温材料、结构材料以及“合成木材”等。在日本、美国等国家中,硬质泡沫主要用途是用做设备绝热、冷库、冷冻机、船舶、车辆等绝热  相似文献   

5.
介绍了冰箱用硬质聚氨酸泡沫塑料(简称硬泡)的制备工艺,设计了冰箱用硬泡生产过程中的质量控制流程。实践证明,质量控制流程为保证生产提供了一套较完整、规范的管理方法。  相似文献   

6.
(二)半硬质聚氨酯泡沫塑料半硬质聚氨酯泡沫塑料(简称半硬泡,亦称半软泡)主要用做汽车冲击吸收材料如汽车的护手、门镶板等安全配件。近几年高密度半硬质泡沫作为鞋底材料,大量代替了橡胶制品,开辟了新的用途。半硬质泡沫塑料的物理一机械性能处于软一硬泡沫之间,故也有人称为“半软质”泡沫塑料。但其组成的基础原料:聚醚多元醇的分子量,并非处于“软一硬”之间。一般,硬质聚氨酯泡沫塑料的多元醇要求分子链要短,官能度要多(3—7个官能度),而  相似文献   

7.
以一种多元胺类副产物为起始剂,制备了一种叔胺基聚多元醇。它具有粘度低,反应活性高,与其它多元醇相窝性好,价格低等优点,它用于硬质聚氨酯泡沫塑料制备时,使泡沫的强度,泡孔结构等得到明显改善,在聚氨醌泡生产领域具有良好的发展前途。  相似文献   

8.
以聚氯乙烯(PVC)为基体,马来酸酐为接枝剂,异氰酸酯、三聚氰胺为交联剂,制备出性能优异的硬质交联PVC泡沫塑料;通过红外光谱、热失重和热机械分析及凝胶含量测定对硬质交联PVC泡沫塑料进行分析,证实交联反应发生在水煮工艺阶段,玻璃化转变温度在180℃左右;研究了马来酸酐用量对硬质交联PVC泡沫塑料凝胶含量的影响,马来酸酐的用量在塑化成型阶段对交联度的影响较小,硬质交联PVC泡沫塑料的凝胶含量随着马来酸酐用量的增加而增大;用光学显微镜对硬质交联PVC泡沫塑料的泡孔直径进行了测量。结果表明,硬质交联PVC泡沫塑料的泡孔直径分布较为均匀,密度为60 kg/m3的泡孔直径主要分布在100~130μm,密度为90 kg/m3的泡孔直径主要分布在70~80μm;测定了硬质交联PVC泡沫塑料的力学性能,结果显示,其具备同瑞士Airex C70产品相当的力学性能。  相似文献   

9.
阻燃型硬质聚氨酯泡沫塑料研究进展   总被引:2,自引:0,他引:2  
对硬质聚氨酯泡沫塑料燃烧机制、阻燃剂的阻燃原理以及硬泡常用阻燃剂进行了全面综述,并总结了阻燃硬质泡沫塑料待研究解决的相关技术问题,提出了相应的研究思路,最后阐述了硬质泡沫塑料阻燃发展前景。  相似文献   

10.
朱则刚 《聚氨酯》2013,(4):52-59
硬质聚氨酯泡沫塑料,简称聚氨酯硬泡,它在聚氨酯制品中的用量仅次于聚氨酯软泡。聚氨酯硬泡,是由硬泡聚醚多元醇(聚氨酯硬泡组合聚醚又称白料),与聚合MDI(又称黑料)反应制备的。主要用于制备硬质聚氨酯泡沫塑料,广泛应用于冰箱、冷库、喷涂、太阳能、热力管  相似文献   

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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   

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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   

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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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