铝包膜TiO2的膜层结构对颜料性能的影响

以偏铝酸钠为包膜剂，采用液相沉淀法在TiO2粒子表面包覆Al2O3膜。采用TEM、SEM、XRF等手段表征无机膜层，通过测试包膜TiO2样品的耐候性、光泽度、亮度等评价其颜料性能。研究以HRTEM结合晶格计算分析膜层氧化铝晶型，并对包膜pH和温度对包膜TiO2的膜层结构和颜料性能的影响进行了实验研究。结果表明，酸性条件下包膜TiO2的膜层氧化铝为无定形，样品耐候性较优；pH=10时膜层氧化铝为勃姆石型和拜耳石型混合晶型，以勃姆石型为主，产品颜料性能优异；pH>11时膜层氧化铝为拜耳石型，产品颜料性能较差。温度升高会增加膜层氧化铝的结晶度，提高包膜TiO2产品的颜料性能。     

提高包膜钛白颜料性能的试验研究

分析了不同包膜因素、包膜剂加入量及包膜工艺对包膜二氧化钛颜料性能的影响。结果表明,在TiO2粒子表面包覆二氧化硅的量最好为2％～3％,得到的包膜钛白粉的耐候性和消色力迭到最佳,而采用复合单包铝的工艺也可以迭到既能提高二氧化钛的耐候性,又不降低二氧化钛的消色力等颜料性能指标的目的,有利于提高二氧化钛制品的应用性能和延长其使用寿命。     

氯化法钛白粉表面处理影响因素研究

结合氯化法钛白粉性能要求,介绍了钛白粉无机表面处理的机理及工艺,分析了二氧化钛浆料的分散性、pH值、包膜处理剂的加入量及加入顺序、反应温度、反应速度和时间对钛白粉包膜的影响,提出了一种硅-铝二元包膜方法技术。结果表明此技术包膜均匀,得到的产品白度大于93.7%,消色力110~113之间,耐候性良好。     

钛白粉的 Zeta电位对丙烯酸乳胶漆应用性能的影响

采用 Nano Zs-90型 Zeta电位仪对不同硅铝包膜金红石型钛白粉的 Zeta电位进行研究，通过测试不同等电点 pH的钛白粉颜料制备的丙烯酸乳胶漆的分散、遮盖、耐候性、光泽等主要性能指标，来指导丙烯酸乳胶漆用钛白粉的生产。结果表明钛白粉的硅铝包膜量、 pH以及电阻率对钛白粉的 Zeta电位有非常大的影响，较高 SiO2包膜的钛白粉可降低等电点 pH，提高丙烯酸乳胶漆的分散性、遮盖力和耐候性。     

超细氧化钛无机改性研究

通过对超细TiO2进行无机包硅改性实验,研究了氧化钛分散性、加酸方式、包覆pH值、改性温度及陈化时间等对包覆效果的影响,分析了致密二氧化硅包覆膜的形成机理,并利用透射电子显微镜TEM和红外分析仪IR对产物进行分析表征,得出无机包硅氧化钛的最佳条件:采用撞击流 旋转填料床反应器(IS RPB),包膜pH=9～10,温度为80～90℃,陈化1h。     

致密硅包膜TiO_2颜料

一、前言 TiO_2颜料用硅包膜时,通常是将TiO_2与可溶性硅酸盐混合,然后用酸(通常为无机酸)中和,析出分子量较大的硅凝胶松驰地粘附在TiO_2表面上,形成多孔状、不连续的硅包膜。五十年代末美国杜邦公司首先以专利形式发表了形成致密“皮肤”状SiO_2包膜的方法。以后该法为钛白制造者所引用,陆续出现了用致密SiO_2、致密硅酸铝包膜TiO_2的报道。例如杜邦的TiO_2产品R-960,是属于有最高耐候性的品种,可     

提高银白珠光颜料质量的工艺研究

以生产钛白粉的中间产物硫酸氧钛为原料,用尿素作中和剂,制备银白珠光颜料。研究了钛液中铁的含量、终点pH值、尿素加入量、升温速率和反应时间,以及加入不同掩蔽剂对云母钛珠光颜料产品白度和亮度的影响。试验结果表明,利用冷冻除铁后的钛液,调节终点pH值为1.5,尿素与TiO2质量比为(5～7)∶1,缓慢升温反应4～5h,并加入硅酸盐等掩蔽剂后,所得银白珠光颜料与纯硫酸氧钛所制的产品白度相当,且亮度很好。     

双覆层包膜法制备彩色云母珠光颜料

通过双覆层包膜法在自制云母钛表面包覆一层其它金属氧化物,而制备出彩色云母珠光颜料.钴着黑色珠光颜料的最适宜工艺条件为:水解温度100℃,pH值7～8,对应于10 g云母钛的硝酸钴加入量为25～30 mL,水解反应时间为2.0 h,煅烧条件是在600℃下保温1.5 h.镍着灰绿色珠光颜料的最适宜工艺条件为:水解温度90 ...     

水性油墨用TiO_2表面致密磷硅铝包膜处理的研究

采用不同配比的硅酸钠和偏铝酸钠作为二氧化钛包膜剂,聚合磷酸盐作为硅酸钠包膜二氧化钛的分散剂,在80~95℃的温度下,进行复合包膜;再经过洗涤,干燥,气流微粉碎,获得致密磷硅铝包膜二氧化钛颗粒。测试分析了包膜处理后Ti O2颗粒的形貌、粒度、表面组成、白度、光泽度和黏度等,结果发现硅酸钠添加量为2.50%,偏铝酸钠的添加量为1.50%~2.00%时,可以得到均匀致密的复合包覆层。     

交联型氟树脂与涂料性能关系的研究

3.4.2色漆的耐候性采用2种不同的TiO2(A)和TiO2(B),前者经表面化学处理(SiO2、Al2O3处理),分别与TFE型FEVE和CTFE型FEVE配制涂料,用砂磨分散至细度不大于10μm,经SW M试验后光泽保持情况见图2。用TiO2(A)(超耐候)作为颜料,每种FEVE(无论是CTFE还是TFE)的涂层表面经4000h曝晒后,光泽保持率高,相反用TiO2(B)(一般)作为颜料,涂层表面经3000h曝晒后光泽降低,用TiO2(B)的TFE型FEVE(4F-B)比CTFE型TEVE失光更多。其差别不是由于TFE型FEVE比CTFE型TEVE对光催化反应性差,而是因为TFE型FEVE对TiO2颜料的分散能力…     

Insect antifeedant properties of anthranoids from the genusVismia

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.     

Direct observation of freeze-thaw instability of latex coatings via high pressure freezing and cryogenic SEM

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.     

Ethanol and (−)-α-Pinene: Attractant Kairomones for Bark and Ambrosia Beetles in the Southeastern US

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.     

Methyl 2,4,6-decatrienoates Attract Stink Bugs and Tachinid Parasitoids

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.     

2007～2008年世界塑料工业进展

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.     

2005～2006年国外塑料工业进展

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。