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1.
丙烯酸酯共聚改性水性聚氨酯的研究进展   总被引:1,自引:0,他引:1  
综述了丙烯酸酯共聚改性水性聚氨酯的3种方法嵌段共聚改性、表面接枝共聚改性以及核-壳种子共聚改性;讨论了丙烯酸酯改性水性聚氨酯的发展趋势.  相似文献   

2.
丙烯酸酯改性水性聚氨酯的研究进展   总被引:5,自引:0,他引:5  
赵灵霞  钱公望 《中国胶粘剂》2006,15(5):34-36,41
详细介绍了丙烯酸酯改性水性聚氨酯的三种方法:共混改性,复合乳液共聚改性,接枝共聚改性, 综述了国内外丙烯酸酯改性水性聚氨酯的研究进展。  相似文献   

3.
水性聚氨酯的改性研究进展   总被引:4,自引:0,他引:4  
介绍了水性聚氨酯复合改性的几种方法和特点,其中包括用具有不同活性基团的有机硅改性、环氧树脂直接或间接改性、丙烯酸酯对水性聚氨酯的共聚改性、核壳结构乳液聚合改性、互穿网络法改性及其它改性。并指出了水性聚氨酯复合改性技术进一步发展的方向。  相似文献   

4.
介绍了丙烯酸酯改性水性聚氨酯乳液(PUA)的制备方法,其中包括乳液型丙烯酸酯改性水性聚氨酯、单体丙烯酸酯改性水性聚氨酯、溶剂型丙烯酸酯低聚物改性水性聚氨酯,指出了各改性方法的优缺点;概述了国内外的研究现状,对丙烯酸酯改性水性聚氨酯前景进行了展望。  相似文献   

5.
丙烯酸酯对水性聚氨酯胶粘剂的改性研究   总被引:11,自引:2,他引:9  
项尚林  陈瑞珠  乔海霞 《粘接》2006,27(3):12-14
用自乳化的方法制备水性聚氨酯(PU)乳液,然后用丙烯酸酯进行改性,制备出水性聚氨酯和丙烯酸酯共聚乳液(PUA),并把聚丙烯酸酯(PA)乳液与PU乳液不同比例共混。考查了共聚型和共混型PUA乳液胶膜的吸水性、热行为、黏度、T型剥离强度。结果表明,在复合薄膜应用方面,共聚型PUA乳液的性能优于共混型PUA乳液。  相似文献   

6.
水性聚氨酯的改性研究   总被引:12,自引:3,他引:9  
分别采用丙烯酸酯、环氧树脂合成2种不同的改性水性聚氨酯,比较了改性前后及2种不同的改性水性聚氨酯在乳液、涂膜性能及粘接性能方面的差异。结果表明,改性后的水性聚氨酯综合性能明显提高,其中环氧树脂改性水性聚氨酯(EPU)在固化交联后涂膜的耐水、耐溶剂及力学性能又明显好于丙烯酸酯改性水性聚氨酯(PUA),其粘接强度与溶剂型聚氨酯相当;而采用丙烯酸酯改性的水性聚氨酯PUA乳液稳定性好于EPU乳液。  相似文献   

7.
共聚改性水性聚氨酯 WPU 可以有效的提高其耐热性、耐水性和力学性能,并且能够很好的将共聚材料与WPU的优点结合起来。本文重点介绍了环氧树脂、丙烯酸酯、有机硅和有机氟共聚改性WPU的研究进展,并对共聚改性WPU的发展现状进行了分析和展望。()  相似文献   

8.
介绍了有机硅改性水性聚氨酯(WPU)的特点,综述了近年来有机硅封端、嵌段共聚及其与丙烯酸酯复合改性制备有机硅改性WPU的研究进展;最后对有机硅改性WPU的研究方向进行了展望。  相似文献   

9.
第三代水性聚氨酯研制成功以马来酸酐为原料制备聚氨酯一丙烯酸酯共聚乳液新工艺由江苏石油化工学院研制成功。聚氨酯-丙烯酸酯共聚乳液被称作第三代水性聚氨酯,新工艺毒性小、价格便宜,并可常规进行有皂或无皂液共聚,产品的耐水性提高,产品同时兼具聚氨酯和丙烯酸酯...  相似文献   

10.
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   

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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   

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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   

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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