热致可逆变色微胶囊乳液的制备与性能研究

本文采用结晶紫内酯,双酚A和正癸酸双酯为可逆变色乳液的芯材,聚苯乙烯为壁材,制备了一种具有热致可逆变色的微胶囊乳液。利用红外光谱,透反射显微镜,纳米粒度仪和紫外光谱仪对其基本性能进行表征。实验结果表明,当n结晶紫内酯:n双酚A=1:2时,得到的芯材颜色最深。当十二烷基硫酸钠的用量为0.02mol/L时,粒径分布在1000-2000nm,单分散性好,形貌呈球形,通过循环升降温测试,表明其具有良好的热致可逆变色能力。     

不同形貌CaO2的制备及其降解水中结晶紫的研究

为探究不同形貌过氧化钙对染料降解去除效果的差异性,采用钙盐法在不同条件下制备不同形貌的过氧化钙,并将其用于处理结晶紫模拟的染料废水。通过X射线衍射、扫描电子显微镜和傅里叶变换红外光谱对制得的过氧化钙进行了形貌表征,证明合成了四方晶状过氧化钙和球状纳米过氧化钙,并考察了两种过氧化钙在不同条件下对模拟染料废水中结晶紫的去除效果。结果表明,在模拟染料废水初始pH为6.0,结晶紫初始浓度为10 mg/L,四方晶状过氧化钙投加量为18.0 mg,球型纳米过氧化钙投加量为30.0 mg时,结晶紫的去除率分别可以达到94.14%和85.49%。准一级动力学方程可以描述两种过氧化钙对结晶紫的降解机制,球状纳米过氧化钙对结晶紫的降解过程与准一级动力学模型的吻合度更高。     

高固含量耐磨有机-无机纳米复合乳液的制备研究

借助含活泼双键的硅烷偶联剂KH-570,将纳米硅溶胶通过化学键接枝在丙烯酸酯聚合物结构上,研究制备了一种固含量49%的高耐磨有机-无机纳米复合乳液。对制备的纯丙乳液和复合乳液性能进行测试表征,确定无机材料的接枝改性,结果表明,复合乳液有更好的成膜性能,附着力较自制纯丙乳液提升57%,耐磨性较某进口纯丙乳液提高20%。     

导读

正肖龙等借助含活泼双键的硅烷偶联剂KH-570,将纳米硅溶胶通过化学键接枝在丙烯酸酯聚合物结构上,研究制备了固含量49%的高耐磨有机-无机纳米复合乳液。对制备的纯丙乳液和复合乳液性能进行测试表征,确定无机材料的接枝改性,结果表明,复合乳液有更好的成膜性能,附着力较自制纯丙乳液提升57%,耐磨性较某进口纯丙乳液提高20%。     

一种针状纳米碳酸钙的制备方法

用石灰乳液碳酸化法制备出针状纳米碳酸钙微粒,讨论了碳化温度和结晶导向剂用量等因素对纳米碳酸钙粒径和形貌的影响。结果表明:结晶导向剂用量为1%~3%(质量分数),温度为14℃,氢氧化钙浆液浓度为8%~12%(氢氧化钙占浆液的质量分数),CO2气体浓度为40%~60%(体积分数),搅拌速度为200~300 r/m in时能制备出长径比大、粒径分布均匀、分散性好的产品;并采用TEM,XRD对其结构进行了表征。     

W／O微乳液制备纳米粒子的研究

介绍了微乳液的制备方法、微观结构模型和形成理论;介绍了W／O型微乳液在制备纳米粒子方面的应用,并对微乳液法制备纳米粒子的方法、原理、影响因素以及纳米粒子的表征方法进行了重点介绍。     

液体石蜡乳液中制备纳米氢氧化铝

在液体石蜡微乳液中采用沉淀法制备了尺寸在20nm-30nm之间,粒度均匀,且分散性良好的球形纳米氢氧化铝颗粒。用TEM,XRD和DSC—TG等手段对产物进行了表征。结果表明样品主要以结晶形态存在,具有一定的疏水性,具有比较高的热效应温度,适合用作聚合物的阻燃剂。     

多重乳液法制备空腔状纳米二氧化钛

采用多重乳液法制备纳米二氧化钛,研究了运用多重乳液法制备二氧化钛的现实意义。将钛酸四正丁酯以一定比例溶于外油相中,再加入一个水包油的微乳液内相,生成O／W／O型多重乳液体系,钛盐在水相中水解形成空腔状的纳米二氧化钛颗粒,用X光衍射仪对其进行了表征,得知产物为锐钛型纳米TiO2,并进行了紫外一可见吸收分析。结果表明,材料吸收带有一定程度的蓝移,即表明纳米颗粒变小,纳米尺寸效应明显。     

PUA离聚物的纳米SiO2复合乳液制备与性能

用共混法和原位聚合法制备了PUA离聚物的纳米SiO2复合乳液,激光粒度分布仪检测表明SiO2在复合乳液中呈现纳米尺寸分布,对乳液的稳定性、粘度与涂膜的光学性能、机械性能等进行了表征。结果证明纳米SiO2的加入能显著改善涂膜的紫外光吸收性能、热学性能及机械性能。     

纳米SiO_2改性纯丙乳液的制备与表征

采用硅烷偶联剂KH570对纳米SiO2进行表面改性,有效改善了纳米SiO2的表面性能。通过预乳化种子乳液法制备了纳米SiO2改性纯丙乳液,并对改性前后的SiO2、纯丙乳液及改性纯丙乳液进行红外和X-射线衍射分析表征。     

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。