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1.
水性聚氨酯改性及其应用研究进展   总被引:1,自引:1,他引:0  
综述了WPU(水性聚氨酯)共聚改性的几种方法(包括有机硅改性、丙烯酸酯改性、环氧树脂改性和纳米材料改性等),介绍了WPU在涂料、皮革加工、胶粘剂及纺织加工等行业的应用现状,指出了改性WPU的发展趋势。  相似文献   

2.
建筑用水性聚氨酯涂料的研究进展   总被引:1,自引:0,他引:1  
综述了建筑用水性聚氨酯(WPU)涂料的改性技术的研究进展,其改性技术包括交联改性、丙烯酸酯改性、环氧树脂改性、植物油改性和纳米材料改性等,并对建筑用WPU涂料的发展前景作了展望。  相似文献   

3.
综述了水性聚氨酯(WPU)涂料在汽车底漆、中涂漆、面漆的应用现状。介绍了几种汽车用WPU涂料改性方法,如环氧树脂改性、有机氟改性、有机硅改性、纳米改性和植物油改性等;讨论了这些改性方法的特点以及用于汽车涂料方面的最新进展。最后展望了WPU在汽车涂料方面的应用前景。  相似文献   

4.
综述了辐照水性聚氨酯(WPU)最常用的多元改性方法,重点介绍了γ射线(Co-60)辐照WPU和紫外光(UV)固化WPU的改性方法。改性后的辐照WPU的耐候性和机械性能要远优于WPU,辐照WPU经改性后可应用于印花粘合剂、地板涂料、木器漆涂料和汽车漆膜等领域。最后展望了辐照WPU的发展前景。  相似文献   

5.
水性聚氨酯(WPU)广泛应用于建筑、涂料、电气绝缘及国防等领域,但是由于WPU制备过程中会引入亲水基团,导致其耐水耐油性、耐化学品性、耐候性等不如人意,需对其进行改性。本文对WPU的最新改性方法,如有机硅改性、有机氟改性、丙烯酸酯改性、环氧树脂改性、纳米无机材料改性等进行了综述,并对WPU改性研究方向进行了展望。  相似文献   

6.
水性聚氨酯涂料的研究与应用   总被引:2,自引:0,他引:2  
杨惠弟 《山西化工》2007,27(6):27-30
综述了水性聚氨酯(WPU)涂料的性能及其组成,介绍了WPU涂料的种类和改性方法,阐述了其应用领域及进展。  相似文献   

7.
氧化石墨烯(GO)是一种新兴的无机纳米材料,研究其改性方法并将其分散到水性聚氨酯(WPU)基体中,提高了无机/有机复合材料的力学、热学性能和抗菌等性能。该文梳理了GO的改性方法,并综述了GO/WPU复合材料在涂料、复合膜、胶黏剂领域的发展及应用,对绿色环保低碳WPU的发展提供了参考。  相似文献   

8.
涂料用水性聚氨酯研究进展   总被引:1,自引:0,他引:1  
介绍了水性聚氨酯(WPU)涂料的主要种类和各种水性聚氨酯涂料适合应用的领域,综述了近年来市场上常用水性聚氨酯涂料合成和改性方法,分别介绍了环氧树脂改性,有机硅改性和纳米材料改性方法,对各项改性方法的特点和改性过程进行了总结,最后通过分析水性聚氨酯涂料的性能特点和应用现状,结合目前国内水性聚氨酯的发展水平,提出了未来水性聚氨酯涂料的研究方向。  相似文献   

9.
环保节能型水性聚氨酯建筑涂料研究进展   总被引:1,自引:0,他引:1  
综述了近几年来环保型、节能型水性聚氨酯涂料的研发和应用情况。主要包括:水性聚氨酯(WPU)保温隔热涂料,以聚氨酯为壳层材料的相变储能材料,UV固化WPU工艺,提高水性聚氨酯涂料的耐水性和防霉抗菌性等。  相似文献   

10.
油墨用水性聚氨酯的研究进展   总被引:1,自引:0,他引:1  
介绍了水性聚氨酯(WPU)改性的几种方法,其中包括丙烯酸酯改性、有机硅改性、环氧树脂(EP)改性、有机氟改性、纳米材料改性和蒙脱土改性等,概述了WPU油墨的研究现状,并对WPU油墨的前景作了展望。  相似文献   

11.
12.
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   

13.
14.
Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.  相似文献   

15.
16.
2008~2009年世界塑料工业进展   总被引:4,自引:1,他引:3  
收集了2008年7月~2009年6月世界塑料工业的相关资料,介绍了2008~2009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、环氧树脂、不饱和聚酯树脂)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   

17.
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   

18.
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   

19.
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   

20.
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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