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1.
何丽红  周超  李力  卢章天 《精细化工》2014,(9):1061-1064
针对无机二氧化钛(TiO2)粒子在有机体系中的分散性问题,采用硅烷偶联剂KH-570对无机填料钛白粉(二氧化钛,TiO2)的表面进行有机化改性;并通过红外光谱(FTIR)、接触角测试、沉降实验、扫描电子显微镜(SEM)等手段表征表面改性TiO2粒子的结构,测试其超疏水性能,分析超疏水表面形成的机理。结果表明,经KH-570表面改性的TiO2粒子的疏水性和分散性得到明显改善,当KH-570质量分数达到15%时,表面改性的TiO2涂层与水的静态接触角达152.5°,表现出良好的超疏水性能。  相似文献   

2.
针对无机二氧化钛(TiO2)粒子在有机体系中的分散性问题,采用硅烷偶联剂KH-570对无机填料钛白粉(二氧化钛,TiO2)的表面进行有机化改性;并通过红外光谱(FT-IR)、接触角测试、沉降实验、扫描电子显微镜(SEM)等手段表征表面改性TiO2粒子的结构,测试其超疏水性能,分析超疏水表面形成的机理。结果表明,经KH-570表面改性的TiO2粒子的疏水性和分散性得到明显改善,当KH-570质量分数达到15%时,表面改性的TiO2涂层与水的静态接触角达152.5˚,表现出良好的超疏水性能。  相似文献   

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以甲基丙烯酸甲酯、丙烯酸丁酯和丙烯酸为主要原料,1,3,5-三(甲基三氟丙基)环三硅氧烷(D3F)和硅烷偶联剂γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)分别为含氟及含硅改性单体,采用酮肼交联体系,通过溶液聚合合成了改性水性聚丙烯酸酯乳液。考察了改性单体用量对乳液稳定性、粒径及浇铸膜吸水率的影响,并对乳液浇铸膜进行了表面水接触角的测定,热重分析及红外表征。结果表明,D_3F与KH-570接入丙烯酸酯链段中,改性单体的加入使丙烯酸酯膜的吸水率降低,表面性能提升,热稳定性提高。当D_3F∶KH-570质量比约为4∶1时,胶膜吸水率低,表面接触角超过90°,热稳定性高,综合性能更好。  相似文献   

4.
硅烷偶联剂对纳米氧化锌的表面改性研究   总被引:3,自引:0,他引:3  
采用硅烷偶联剂KH-570对纳米ZnO进行表面改性,研究了硅烷偶联剂用量、pH值、时间及反应温度等因素对纳米ZnO表面改性的影响,利用亲油化度实验、红外光谱(IR)、热重(TG)、透射电镜(TEM)等手段表征了纳米ZnO的改性效果和结构。红外光谱和热重研究表明,KH-570以化学键合的方式结合在纳米ZnO的表面,并形成了有机包覆层。经测量,纳米ZnO表面的KH-570的质量分数为4.6%;讨论了产生KH-570理论包覆量与实际包覆量差异的原因。TEM图表明经KH-570改性过的纳米ZnO的分散性大大提高;亲油化度实验表明,当硅烷偶联剂用量为6%,pH值为6.5,反应温度为85℃,反应2 h时,纳米ZnO改性效果最好。  相似文献   

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采用硅烷偶联剂KH-570与钛酸酯偶联剂JN-114对硅灰石进行干法表面改性,研究了改性剂种类及用量、改性温度和改性时间对改性效果以及聚丙烯复合材料性能的影响。结果表明,采用KH-570改性的最佳工艺:KH-570用量3.0%(w),常温,时间30 min,此条件下得到的改性硅灰石活化指数95.45%,水接触角91.25°;采用JN-114改性的最佳工艺:JN-114用量1.0%(w),温度70℃,时间30 min,此条件下得到的改性硅灰石活化指数98.16%,水接触角83.57°;KH-570与JN-114均以化学吸附作用于硅灰石表面。采用硅灰石填充聚丙烯,KH-570改性的硅灰石提高了聚丙烯复合材料的拉伸强度、弯曲强度与模量,而JN-114改性的硅灰石能有效提高聚丙烯复合材料的冲击强度与熔体流动性。  相似文献   

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含氟硅丙烯酸酯核壳乳液及涂膜表面性能   总被引:3,自引:0,他引:3       下载免费PDF全文
徐蕊  肖新颜 《化工学报》2009,60(12):3142-3147
在可聚合阴离子乳化剂体系下,以甲基丙烯酸甲酯(MMA)、丙烯酸丁酯(BA)为主要单体,甲基丙烯酸十二氟庚酯(DFMA)、γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)为功能单体,采用半连续种子乳液聚合法合成了含氟硅丙烯酸酯核壳乳液。考察了DFMA和KH-570用量对乳液聚合过程和乳胶膜表面疏水性能的影响,并对乳胶膜的表面自由能进行了估算。采用傅里叶红外光谱(FT-IR)、差示扫描量热仪(DSC)、热重(TG)、接触角(CA)及X射线光电子能谱(XPS)对氟硅丙乳液及乳胶膜进行了表征。研究结果表明,氟硅单体有效地参与了聚合,乳胶膜中氟硅元素呈梯度分布,当氟硅丙乳液中DFMA和KH-570用量分别为16%和5%(质量分数)时,涂膜-空气界面与去离子水的接触角为110.6°,涂膜的表面能低至15.4 mN·m-1,其疏水性和耐热性有较大幅度提高。  相似文献   

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利用硅烷偶联剂KH-570对表面无机包覆SiO2前、后的六钛酸钾晶须(PTW)进行有机表面改性,比较了硅烷偶联剂改性无机包覆SiO2处理前、后的PTW对卷材涂料隔热性能的影响.采用红外光谱(IR)、热重分析(TG)方法对改性前后的PTW进行了表征.结果表明,SiO2以化学键键合在PTW表面,KH-570在PTW表面形成了有机包覆层.涂膜隔热性能测试结果表明,以9%SiO2包覆处理后再用偶联剂KH-570改性的PTW能明显改善隔热卷材涂料的隔热性能,其热反射率达到75.4%,比不含PTW的漆膜提高了34.4个百分点,比含直接用偶联剂KH-570改性的PTW的漆膜提高了12.8个百分点.  相似文献   

8.
溶胶-凝胶法制备KH-570改性纳米二氧化钛及其表征   总被引:1,自引:0,他引:1  
以钛酸丁酯(TBOT)为前驱物,盐酸为催化剂,γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)为改性剂,采用溶胶-凝胶法原位制备了KH-570改性的纳米二氧化钛,研究了KH-570用量对纳米二氧化钛表面改性效果的影响,并采用红外光谱(FT-IR)、X射线衍射(XRD)、粒径分析等手段对纳米二氧化钛进行了表征。结果表明:KH-570接枝到纳米二氧化钛表面,纳米二氧化钛为锐钛矿型;随着KH-570用量的增大,接枝率先上升然后稍有下降,当KH-570用量为TBOT质量的14.57%时,接枝率达到25.6%;与未加KH-570制备的二氧化钛相比,KH-570改性纳米TiO2的平均粒径减小且分布变窄,亲油性得到明显提高。  相似文献   

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偶联剂复合改性绢云母的研究   总被引:2,自引:0,他引:2  
用硅烷偶联剂(silane coupling agent,SCA)、γ-缩水甘油醚氧基丙基三甲氧基硅烷(KH-550)、γ-氨基丙基三乙氧基硅烷(KH-560)、γ-(甲基丙烯酰氧基)丙基三甲氧基硅烷(KH-570)对片状绢云母进行表面改性。红外光谱分析结果表明:SCA通过与绢云母表面的羟基发生化学键合而实现对超细绢云母表面的修饰改性。扫描电镜(SEM)和接触角测试表明:KH-550和KH-570对绢云母改性效果较佳,KH-560改性效果相对较差。在此基础上,进一步研究了KH-550和KH-570对绢云母的复合改性,结果表明:复合改性后绢云母的疏水亲油性得到更大的提高,对绢云母的表面改性效果最佳。  相似文献   

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采用γ-甲基丙烯酰氧基丙基三甲氧基硅烷(KH-570)对硅溶胶改性,将改性的硅溶胶与聚氨酯丙烯酸酯(PUA)低聚物共混,制备出聚碳酸酯(PC)用紫外光(UV)固化耐磨涂层。用红外光谱仪、热重分析仪、激光粒度仪、接触角测量仪对改性前后的纳米二氧化硅(SiO_2)进行了分析表征,并对制备的UV固化涂层的透光率、雾度、表面硬度和附着力进行了测试。结果表明:纳米SiO_2表面接枝上了KH-570,且亲水性降低。当KH-570用量为60%、改性纳米SiO_2用量为4%时,涂覆UV固化涂层的PC的耐磨性得到最佳改善,耐磨试验后,涂覆添加4%改性纳米SiO_2的UV固化涂层的PC较涂覆未添加纳米SiO_2的UV固化涂层的PC,透光率降低值从4.5%降至1.1%,雾度增加值从21.29%降至3.41%,PC表面涂层的铅笔硬度达到2H。  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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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   

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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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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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