纳米复合丙烯酸水性外墙涂料的研制

探索纳米SiO2在水性丙烯酸外墙涂料中的应用方式、应用效果及其相关因素的影响。采用丙烯酸乳液原位聚合的方式对纳米SiO2粉体进行表面改性,形成纳米SiO2丙烯酸复合乳液。以此纳米复合乳液与相应的颜、填料和助剂复配得到纳米复合外墙水性涂料。     

硅基-纳米SiO2改性丙烯酸/环氧乳液的制备及其涂层性能研究

用丙烯酸类单体接枝改性环氧树脂E-20,通过红外光谱仪、热重分析仪等证实得到了丙烯酸类单体改性的水性环氧树脂乳液,用有机硅氧烷对纳米SiO_2进行表面修饰制备分散液加入丙烯酸接枝改性的水性环氧乳液中,利用改性后乳液制备出具有环境友好型、耐水时间长、高效防腐的水性涂料,其中VOC含量为125 g/L,耐水性和耐中性盐雾实验分别为720 h和800 h。     

丙烯酸高级酯共聚物组成与其无皂乳液稳定性研究

制备了不同分子结构的丙烯酸高级酯共聚物无皂乳液,测定了丙烯酸和甲基丙烯酸十六酯的竟聚率,考察了共聚物的组成对无皂乳液电解质稳定性、机械稳定性和pH值稳定性的影响。结果显示,丙烯酸竟聚率为2.32,甲基丙烯酸十六酯竟聚率为0.59,随共聚物中丙烯酸组分含量增加,乳液粒子表面羧基含量增大,乳液机械稳定性和pH值稳定性提高,乳液适合在偏碱性条件下使用。     

纳米TiO_2改性丙烯酸乳液制备防滑膜的研究

水性丙烯酸乳液因其环保性而越来越多地被应用到涂布中,但若用于塑料薄膜涂布,则须先对丙烯酸乳液进行改性,以增加其耐水性和防滑性。采用硅烷偶联剂KH-570改变纳米TiO_2的表面性能,制备了KH-570/纳米TiO_2;再将其用于改性丙烯酸酯乳液以提高摩擦系数;将改性后的丙烯酸乳液涂覆在PE膜上,制备了防滑膜。结果表明:硅烷偶联剂的质量分数为20%时,KH-570/纳米TiO_2的表面性能最佳,亲油性和分散性明显改善;KH-570/纳米TiO_2与丙烯酸酯乳液的相容性较好,当纳米TiO_2在丙烯酸酯乳液中的添加量(w)为0.1%时,乳液的稳定性和耐水性最佳。对涂覆涂料前后的PE膜进行了附着力、静态接触角、静摩擦系数和剥离力测试,结果表明:改性纳米TiO_2质量分数为0.1%时的乳液,固化后涂层的静摩擦系数最高,粘连程度最低。     

甲基硅油改性丙烯酸树脂乳液的合成与性能研究

本论文以D4、KOH、DMSO、MM、KH-570为原料,通过聚合反应生成含有双键的有机硅低聚物;再以十二烷基苯磺酸钠为乳化剂,过硫酸氢钠为引发剂制备有有机硅改性丙烯酸树脂乳液。然后分别采用傅利叶红外光谱仪、粒径分析仪、热重分析仪等对不同硅含量的丙烯酸树脂乳液进行性能分析和结构表征。结果表明有机硅改性的丙烯酸树脂在1680~1550cm~(-1)区间有很强的吸收峰,说明C=C已经被成功引入;共聚法制出的丙烯酸树脂在一定温度范围内它的失重率小于物理共混法制得的,进而说明其热稳定性更好;对其进行性能分析结果显示出:在有机硅含量为2%时,乳液的耐酸性最好;在有机硅含量为8%时,样品耐碱性最优;在有机硅含量为6%时,乳液的耐热性最强。粒径分析结果显示:化学共聚法优于物理共混法,当有机硅含量为6%时,乳液的稳定性最小。     

醇酸树脂及其涂料

0106024醇酸一丙烯酸复合分散体的动电性能[刊,英]IKulikova,olga A.等泥ur. Coat.J.佗000,(7一8)一32一35 通过将热塑性聚合物分散体与醇酸低聚物乳液复合制成基料,可实现干燥快、对多种底材保护性和附着性好的目的。防止分散体粒子稳定性的退化对于确保这种体系的应用成功是必要的,复合分散相中的不同分散组分都有可能影响分散稳定性。然而,在所有影响因素中,分散体的动电性能是决定性因素。本项研究揭示了用不同类型表面活性剂稳定的丙烯酸分散体一醇酸乳液复合体系,其分散相粒子和分散介质的pH值对动电电位的影响。0106025改进水溶性…     

原位聚合法制备纳米TiO2/硅丙复合乳液

采用硅烷偶联剂对纳米TiO2进行表面处理，使其亲水性表面改为亲油性，并在其表面接枝上可反应的有机官能团，然后通过原位聚合法与有机硅改性丙烯酸聚合物复合，制得性能稳定的纳米TiO2／硅丙复台乳液。采用透射电子显微镜表征了乳液的结构及其形态。     

丙烯酸纳米微乳液、水性热反射隔热涂料及其制造方法

本发明涉及一种丙烯酸纳米微乳液和采用丙烯酸纳米微乳液制造的水性热反射隔热涂料，以及丙烯酸纳米微乳液和水性热反射隔热涂料的制造方法，名称为丙烯酸纳米微乳液、水性热反射隔热涂料及其制造方法。为解决现有的涂料因含有大量有机溶剂会造成环境污染，并且热反射和隔热性能差的技术问题，本发明水性热反射隔热涂料，其原料含有：丙烯酸纳米微乳液、常规丙烯酸乳液、颜料、填料、红外线反射剂、助剂、pH调节剂、增稠剂、软化水，     

原位聚合法制备纳米TiO2／硅丙复合乳液

北京化工大学材料科学与工程学院的徐瑞芬等采用硅丙偶联剂对纳米TiO2进行表面处理，使其亲水性表面改为亲油性，并在其表面接枝上可反应的有机官能团，然后通过原位聚合法与有机硅改性丙烯酸聚合物复合，制得性能稳定的纳米TiO2／硅丙复合乳液。采用透射电子显微镜表征了乳液的结构及其形态。     

DCP对原位聚合改性交联PE-LLD性能的影响

研究了在线形低密度聚乙烯（PE—LLD）中原位聚合丙烯酸钠（NaAA）后，过氧化二异丙苯（DCP）用量对体系力学性能、电气性能、吸水性能的影响。在改性的PE—LLD中，DCP不仅起到交联剂的作用，还作为单体丙烯酸钠的引发剂。实验结果表明：断裂伸长率随DCP增加明显下降；DCP含量对体系电性能有较大影响；介电常数随DCP的增加明显下降，击穿场强有大幅度下降；体系的吸水性能随DCP含量的上升而下降；当DCP含量为1质量份，N如～含量为2质量份。水温为90℃时，体系吸水率达14％。     

Sapindaceae,cyanolipids, and bugs

Scentless plant bugs (Heteroptera: Rhopalidae) are so named because adults of the Serinethinae have vestigial metathoracic scent glands. Serinethines are seed predators of Sapindales, especially Sapindaceae that produce toxic cyanolipids. In two serinethine species whose ranges extend into the southern United States,Jadera haematoloma andJ. sanguinolenta, sequestration of host cyanolipids as glucosides renders these gregarious, aposematic insects unpalatable to a variety of predators. The blood glucoside profile and cyanogenesis ofJadera varies depending on the cyanolipid chemistry of hosts, and adults and larvae fed golden rain tree seeds (Koelreuteria paniculata) excrete the volatile lactone, 4-methyl-2(5H)-furanone, to which they are attracted.Jadera fed balloon vine seeds (Cardiospermum spp.) do not excrete the attractive lactone. Loss of the usual heteropteran defensive glands in serinethines may have coevolved with host specificity on toxic plants, and the orientation ofJadera to a volatile excretory product could be an adaptive response to save time.Mention of a commercial product does not consititute an endorsement by the USDA.     

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.     

2008～2009年世界塑料工业进展

收集了2008年7月～2009年6月世界塑料工业的相关资料,介绍了2008～2009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、环氧树脂、不饱和聚酯树脂)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。     

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.     

Many Drugs of Abuse May Be Acutely Transformed to Dopamine,Norepinephrine and Epinephrine In Vivo

It is well established that a wide range of drugs of abuse acutely boost the signaling of the sympathetic nervous system and the hypothalamic–pituitary–adrenal (HPA) axis, where norepinephrine and epinephrine are major output molecules. This stimulatory effect is accompanied by such symptoms as elevated heart rate and blood pressure, more rapid breathing, increased body temperature and sweating, and pupillary dilation, as well as the intoxicating or euphoric subjective properties of the drug. While many drugs of abuse are thought to achieve their intoxicating effects by modulating the monoaminergic neurotransmitter systems (i.e., serotonin, norepinephrine, dopamine) by binding to these receptors or otherwise affecting their synaptic signaling, this paper puts forth the hypothesis that many of these drugs are actually acutely converted to catecholamines (dopamine, norepinephrine, epinephrine) in vivo, in addition to transformation to their known metabolites. In this manner, a range of stimulants, opioids, and psychedelics (as well as alcohol) may partially achieve their intoxicating properties, as well as side effects, due to this putative transformation to catecholamines. If this hypothesis is correct, it would alter our understanding of the basic biosynthetic pathways for generating these important signaling molecules, while also modifying our view of the neural substrates underlying substance abuse and dependence, including psychological stress-induced relapse. Importantly, there is a direct way to test the overarching hypothesis: administer (either centrally or peripherally) stable isotope versions of these drugs to model organisms such as rodents (or even to humans) and then use liquid chromatography-mass spectrometry to determine if the labeled drug is converted to labeled catecholamines in brain, blood plasma, or urine samples.