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1.
吴长俊  王保金 《辽宁化工》2009,38(9):617-619,642
以水热法自制的纳米氧化锆为原料,用油酸对其进行表面改性。考查了改性温度、油酸用量对改性粉体的分散性的影响。用TEM、SEM对改性粉体进行表征。结果表明,改性后氧化锆从亲水性明显转变为亲油性,在弱极性溶剂中分散效果良好,改性效果明显。  相似文献   

2.
CaCO_3粉体分散性的研究   总被引:4,自引:0,他引:4  
粉体随颗粒细度的增加具有自发团聚的趋势,改善粉体的分散性是实现超细分级的技术关键之一.本文分析了粉体凝聚与分散的作用机理,提出通过表面改性以提高粉体的分散性,并以使用直剪实验测出特定条件下的粉体内聚力作为分散性的表征参数,定量研究了表面改性对CaCO_3粉体分散性的影响.同时还对CaCO_3采用硬脂酸改性前后进行分级实验对比,结果表明改性后的CaCO_3分级效率有明显提高.  相似文献   

3.
超细电气石粉体的表面改性试验研究   总被引:1,自引:0,他引:1  
超细电气石粉体在使用基体中的分散性直接影响其释放负氧离子的性能.本文以提高超细电气石粉体在亲水性体系中的分散性为目的进行了表面改性研究.通过对超细电气石粉体的聚丙烯酸改性处理,并通过对改性前后的样品进行红外光谱分析分析了改性机理.结果表明,对超细电气石粉体进行表面改性时,聚丙烯酸的最优用量为电气石粉体质量的1.0%,改性处理后样品在水中的分散性大大提高.红外光谱分析表明,聚丙烯酸与电气石粉体表面的结合方式为化学吸附.  相似文献   

4.
防腐蚀涂料     
《涂料技术与文摘》2010,31(4):45-47
201004063亚麻籽油形成的聚(酰胺酯-氨基甲酸乙酯)作防腐涂料的合成及其表征:N,N-二(2-羟基乙基)亚麻籽油脂肪酰胺和乙二胺四乙酸经缩聚反应合成乙烯二胺聚酰胺酯(Ed—PEA)。再以不同质量分数2,4-甲苯二异氰酸酯(TDI)处理,获得氨基甲酸乙酯改性聚酰胺酯(Ed—UPEA)。  相似文献   

5.
KH570对二硫化钼粉体表面的改性研究   总被引:3,自引:0,他引:3  
二硫化钼(MoS2)是常用的耐磨无机填料,在加入聚合物基体之前先通常进行表面改性而提高其在聚合物中的分散性和界面相容性.选用硅烷偶联剂(KH570)为改性剂,采用湿法改性工艺对MoS2粉体进行表面改性,通过MoS2粉体悬浮液的浊度、活化指数等性能分析,表明改性后的MoS2粉体疏水亲油性提高.FT-IR及XRD的结构表征表明改性后的MoS2晶体结构未发生改变,粉体粒子表面成功地被KH570包覆.  相似文献   

6.
CTAB对二硫化钼粉体的表面改性实验研究   总被引:2,自引:0,他引:2  
二硫化钼(MoS2)具有层状结构,是聚合物基复合材料常用的无机填料.作者以十六烷基三甲基溴化铵(CTAB)对MoS2粉体进行表面改性,改性后的MoS2粉体在非极性溶剂中的分散性提高,悬浮液的浊度从215提高到345,活化指数从0.42提高到0.82,吸油量降低,透水时间明显延长,结果表明:改性后的MoS2粉体亲油性提高;同时采用FT-IR及XRD对改性前后的MoS2粉体进行了结构表征,分析表明改性后的MoS2粉体粒子表面成功地被CTAB包覆,通过改性MoS2填充型聚苯硫醚(PPS)/聚丙烯(PP)复合材料成型样条的断口SEM表征,结果表明改性MOS2粉体能够在聚合物基体中均匀分散.  相似文献   

7.
为使氢氧化铝粉体在有机介质中具有良好的分散性,采用十三氟辛基三乙氧基硅烷偶联剂在正丁醇溶剂中对其进行表面化学改性处理。并通过傅立叶变换红外光谱仪、接触角测试仪、场发射扫描电镜对改性前后的粉体进行表征分析,通过沉降实验验证改性前后的粉体亲水亲油效果。结果表明:十三氟辛基三乙氧基硅烷偶联剂成功改性氢氧化铝粉体表面,使其具有疏水亲油性,并且改性后的粉体水接触角达到154°,活化指数达到90%,分散效果得到改善。  相似文献   

8.
CaCO3粉体分解性的研究   总被引:11,自引:0,他引:11  
粉体随颗粒细度的增加具有自发团聚的趋势,改善粉体的分散性是实现超分级的技术关键之一。本文分析了粉体凝聚与分散的作用机理,提出通过改性以提高粉体的分散性,并以使用直剪实验同特定条件粉体内聚力作为分散性的表征参数,定量研究了表面改性对CaCO3粉体分散性的影响。同时还对CaCO3采用硬脂入性前后级实验对比,结果表明改性后的CaCO2分级效率有明显提高。  相似文献   

9.
采用正交试验研究了用硼酸酯改性微晶白云母的工艺,并通过粘度、改性粉体/聚氯乙烯复合材料的力学性能和红外光谱测试对改性效果进行了表征.结果表明:用硼酸酯改性的微晶白云母粉体在有机介质中的分散性有明显的提高,可以大幅度增加其在高分子聚合物中的填充量;用硼酸酯对粉体改性能改善粉体/聚氯乙烯复合材料的力学性质;硼酸酯主要以物理吸附方式包覆于微晶白云母粉体表面.  相似文献   

10.
汪海燕  章于川 《应用化工》2009,38(6):779-782,787
采用设计合成的含氟大分子表面改性剂,对纳米S i3N4粉体进行了表面包覆改性处理。应用TEM,FTIR,NMR,TGA等对含氟大分子表面改性剂和表面改性前后的纳米S i3N4粉体进行了表征和分析比较。结果表明,包覆在纳米S i3N4粉体表面的含氟大分子表面改性剂,与其发生了化学键合,有效地阻止了纳米S i3N4粉体的团聚。当含氟大分子表面改性剂用量为7%时,包覆改性后的纳米S i3N4粉体的粒径较小,为64.5 nm,分布最窄,分散性最好。  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.
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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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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