右旋布洛芬/尿素改性蒙脱土复合物的制备及体外释药性能

以蒙脱土为药物载体,利用尿素固相研磨法将蒙脱土层间距撑大,以提高其载药量;采用溶液插层法实现右旋布洛芬的有效负载,制备右旋布洛芬/尿素改性蒙脱土[S(+)-IBU/urea-MMT]复合物;借助X射线衍射(XRD)和傅里叶红外变换光谱(FT-IR)对复合物进行结构表征;采用透析法研究复合物中药物的体外释药性能;运用3种数学模型对其体外释放行为进行拟合分析,探索释药机理。结果表明,在尿素的作用下,蒙脱土的层间距由1.20nm增大到1.79 nm,右旋布洛芬的负载量最高可达227.9 mg·g~(-1),较改性前提高了30%;S(+)-IBU/urea-MMT复合物具有良好的缓释效果,在人工模拟胃液(pH 1.2)和人工模拟肠液(pH 6.8)中的累计释放量分别为19.2%和88.4%;复合物的释药行为基本符合零级释放动力学模型。     

右旋布洛芬/盐酸改性蒙脱土的制备及体外释放性能

为了提高右旋布洛芬的载药量,并探索载药复合物在不同释放介质中的释放规律,本文以盐酸改性蒙脱土为药物载体,用溶液插层法将右旋布洛芬负载于酸化后的蒙脱土上,制得右旋布洛芬/酸改性蒙脱土复合物[S(+)-IBU/acid-MMT],利用XRD、BET、SEM对蒙脱土及S(+)-IBU/acid-MMT进行了结构表征,筛选出最佳酸处理质量分数;采用透析法对S(+)-IBU/acid-MMT进行了体外释放实验。结果表明:经酸改性后蒙脱土的结构发生了改变,当盐酸质量分数为15%时,蒙脱土的比表面积达到最大值246 m2/g,比改性前提高了10.7倍。上载右旋布洛芬后,蒙脱土的载药量最大可达352.4 mg/g,比改性前提高了1.1倍,体外释放实验表明,S(+)-IBU/acid-MMT的累积释药量受p H影响:在12 h内,当p H为1.2和6.8时,其累积释药量分别为18.6%和89.3%。     

右旋布洛芬/尿素改性蒙脱土复合物的制备及体外释药性能

以蒙脱土为药物载体,利用尿素固相研磨法将蒙脱土层间距撑大,以提高其载药量;采用溶液插层法实现右旋布洛芬的有效负载,制备右旋布洛芬/尿素改性蒙脱土[S（+）-IBU/urea-MMT]复合物;借助X射线衍射（XRD）和傅里叶红外变换光谱（FT-IR）对复合物进行结构表征;采用透析法研究复合物中药物的体外释药性能;运用3种数学模型对其体外释放行为进行拟合分析,探索释药机理。结果表明,在尿素的作用下,蒙脱土的层间距由1.20 nm增大到1.79 nm,右旋布洛芬的负载量最高可达227.9 mg·g^-1,较改性前提高了30%;S（+）-IBU/urea-MMT复合物具有良好的缓释效果,在人工模拟胃液（pH 1.2）和人工模拟肠液（pH 6.8）中的累计释放量分别为19.2%和88.4%;复合物的释药行为基本符合零级释放动力学模型。     

右旋布洛芬/盐酸改性蒙脱土的制备及体外释放研究

目的：以酸改性蒙脱土为药物载体,制备右旋布洛芬/酸改性蒙脱土复合物,提高右旋布洛芬的载药量,并探索载药复合物在不同释放介质中的释放规律。方法：首先用浓度为5%~20%的盐酸对蒙脱土进行预处理,利用X-射线衍射（XRD）、比表面积测定（BET）、扫面电子显微镜（SEM）等表征方法对蒙脱土进行结构表征,筛选最佳酸处理浓度;然后用溶液插层法将右旋布洛芬负载于酸化后的蒙脱土上,制得右旋布洛芬/酸改性蒙脱土复合物;采用透析法对右旋布洛芬/酸改性蒙脱土复合体系进行体外释放实验。结果：经酸改性后蒙脱土的结构发生改变,当酸浓度为15%时,蒙脱土的比表面积达到最大值246 m2/g。上载右旋布洛芬后,载药量最大可达352.4 mg/g。体外释放实验表明,右旋布洛芬/酸改性蒙脱土的累积释药百分量受pH的影响,当pH为1.2时,其累积释药百分量为18.6%,当pH为6.8时,则为89.3%。结论：盐酸改性蒙脱土有助于提高药物的负载量,右旋布洛芬/酸改性蒙脱土复合物具有良好的缓释作用并有一定的pH响应性,有望制成肠道缓释口服药物制剂。     

星点设计-效应面法优化制备右旋布洛芬/酸改性蒙脱土

以右旋布洛芬为原料,酸化蒙脱土为药物载体,制得右旋布洛芬/酸改性蒙脱土S(+)-IBU/acid-MMT干混悬剂。通过星点设计-效应面法优化右旋布洛芬/酸改性蒙脱土干混悬剂的制备工艺。以蒙脱土的载药量为考察指标,采用三因素五水平星点设计考察了盐酸浓度、酸化时间、酸化温度对干混悬剂制备工艺的影响,并对结果进行了二元多项式线性回归方程拟合,经效应面法预测最佳处方;借助XRD和SEM技术对干混悬剂进行了结构表征。结果表明,右旋布洛芬/酸改性蒙脱土干混悬剂最佳制备条件为:盐酸浓度3.3 mol/L,酸化时间5.2 h,酸化温度54℃,在该条件下,干混悬剂载药量可达443.7 mg/g,较优化前(352.4 mg/g)提高了25.9%。星点设计-效应面法适用于右旋布洛芬/酸改性蒙脱土干混悬剂制备工艺优化,以该方法建立的数学模型具有良好的预测性,所得干混悬剂具有更高的载药量。     

星点设计-效应面法优化右旋布洛芬/酸改性蒙脱土干混悬剂的制备工艺

通过星点设计-效应面法优化右旋布洛芬/酸改性蒙脱土（S( )-IBU/acid-MMT）干混悬剂的制备工艺。以蒙脱土的比表面积和孔容为考察指标,采用3因素5水平星点设计考察盐酸浓度、反应时间、反应温度对干混悬剂制备工艺的影响,并对结果进行二元多项式线性回归方程拟合,经效应面法预测最佳处方;借助现代分析技术对干混悬剂进行结构表征。右旋布洛芬/酸改性蒙脱土干混悬剂最佳条件为：盐酸浓度3.3 mol/L,反应时间5.5 h,温度55 ℃,酸改性的MMT比表面积达318.8 m2/g,孔容0.51 cm3/g,载药量最高可达460.8 mg/g。星点设计-效应面法适用于右旋布洛芬/酸改性蒙脱土干混悬剂制备工艺优化,以此方法建立的数学模型具有良好的预测性,所得干混悬剂具有更高的载药量。     

有机插层剂对聚酰胺6／MMT纳米复合材料制备的影响研究

以烷基胺、季铵盐和氨基酸作为有机插层剂与蒙脱土片层进行阳离子交换，制备出层间距不同的有机蒙脱土。采用熔融插层法和原位聚合法分别制备聚酰胺（R％）／蒙脱土（MMT）纳米复合材料，并利用XRD、FT-IR、TEM对有机蒙脱土及纳米复合材料进行结构表征。研究结果表明：用烷基胺、季铵盐和氨基酸有机插层剂改性的蒙脱土层间距由原来的1．25nm分别增大到3．21nm、3．99nm和1．82m；季铵盐有机插层剂更适用于熔融插层法制备PA6／MMT纳米复合材料，而氨基酸有机插层剂更适用于原位聚合法制备PA6／MMT纳米复合材料。     

SEBS／蒙脱土复合材料结构与阻燃性能的研究

根据蒙脱土（MMT）特殊的片层结构,采用熔融插层法制备热塑性弹性体SEBS／蒙脱土插层复合材料。通过X射线衍射仪、透射电镜等表征手段研究复合材料的微观结构。使用锥形量热仪评价复合材料的燃烧性能。结果表明,有机蒙脱土（OMMT）片层的间距为1．948nm,SEBS／5％OMMT体系的片层间距为4．307nm,说明聚合物SEBS插入有机蒙脱土片层之间。SEBS／OMMT复合材料具有较低的热释放速率和质量损失速率,且随着OMMT添加量的增加,其热释放速率峰值降低愈明显。通过对复合材料的阻燃性能和微观结构的分析,探讨了其阻燃机理。     

聚乳酸/有机蒙脱土纳米复合材料的制备及降解性能研究

以聚乳酸和有机蒙脱土为原料,通过溶液插层法制备了聚乳酸/有机蒙脱土复合材料,分别用傅立叶变换红外光谱、X.射线衍射、热重分析等对聚乳酸/有机蒙脱土纳米复合材料的结构及热稳定性进行了表征,研究了材料的降解性能.结果表明,在聚乳酸/有机蒙脱土纳米复合材料中蒙脱土层间距为2.21 nm.层间距明显增大,表明聚乳酸分子插入到蒙脱土片层间,形成了插层型纳米复合材料.复合材料的热分解温度提高,热稳定性比纯PLA有明显的提高.在NaOH介质中降解结果表明,材料在碱性介质中降解性能和吸水性能良好.     

聚苯乙烯-丙烯酸酯/蒙脱土纳米复合材料的制备和热性能研究

采用原位乳液聚合法和乳液共混法分别制备聚苯乙烯-丙烯酸酯/蒙脱土(PSB/MMT)复合材料,研究不同类型的蒙脱土对插层结构类型的影响,用X射线衍射(XRD)对其插层结构进行表征,不同方法制备出的复合胶膜具有不同的插层结构,利用TG-DSC分析法分析其热降解性能。结果表明,添加了蒙脱土的PSB/MMT的复合体系热稳定性提高,其中插层型的要优于剥离型。     

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.     

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。     

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.