无机电解质及聚合物对Mg-Al混合金属氢氧化物—高岭土分散体系触变性的影响

类水滑石;流变学;无机电解质及聚合物对Mg-Al混合金属氢氧化物—高岭土分散体系触变性的影响     

邻甲酚在类水滑石、焙烧及改性类水滑石上的吸附

用液相非稳态共沉淀法制备了Mg-Al 类水滑石(HTlc); Mg-Al HTlc 于450 ℃下焙烧得焙烧类水滑石(CHTlc); 采用结构重建法由CHTlc 制备了十二烷基硫酸根(DS－)插层(改性)类水滑石(DS·HTlc). 研究了邻甲酚在Mg-Al HTlc,CHTlc 和DS·HTlc 上的吸附行为: 邻甲酚在Mg-Al HTlc, CHTlc 和DS·HTlc 上的吸附动力学和等温式均分别符合准二级动力学方程和Freundlich 方程, 且吸附速率和吸附量大小均依次为: DS·HTlc>>CHTlc>HTlc; 在初始pH＝5.00～13.00 范围内, 邻甲酚在HTlc 和CHTlc 上的吸附量随pH 值的增加先增加后减小, 随温度的增加而增加, 邻甲酚在DS·HTlc 的吸附量随pH 值和温度的增加而降低; 邻甲酚在HTlc, CHTlc 和DS·HTlc 上的吸附量均随电解质(NaCl)浓度的增加而增加, 探讨了吸附机理. 研究结果表明, DS·HTlc 有望成为一种新型的高效酚类有机污染物处理剂.     

阳离子淀粉/Mg-Al类水滑石悬浮体系的粘度行为

阳离子淀粉;Mg-Al类水滑石;流变性;粘度     

水滑石无机阴离子交换剂的合成与表征

采用水热法制成了镁铝碳酸盐型、镁铝硝酸盐型、镁铝盐酸盐型、镁铝羟基型等插层镁铝类水滑石,比较了层间含不同阴离子类水滑石的结构差异和高温热处理后的结构稳定性.通过离子交换方式以镁铝羟基型为基材插层组装无机阴离子基团MoO42-、WO42-、CO32-和NO3-制得不同的阴离子插层类水滑石.通过XRD、TEM、XPS和热分析方法对镁铝类水滑石和阴离子插层类水滑石进行了表征.     

Mg-Al水滑石催化甘油与碳酸二甲酯的酯交换反应简

报道了温和条件下甘油和碳酸二甲酯在一系列不同Mg/Al比（0.5-6）的Mg-Al水滑石催化下合成碳酸甘油酯（GC）的反应. 发现,Mg-Al水滑石对该反应具有很高的GC选择性,其中Mg/Al=2经400℃处理所得水滑石催化效率最高：70 ℃反应3 h甘油转化率达66.9%时,GC选择性维持在97%以上. 表征结果表明,水滑石样品的比表面积、孔径、结晶度和表面碱性对其催化活性影响很大.     

锌铝类水滑石的复原及表征(英)

本文采用焙烧复原法，在70 ℃以80%的乙醇溶液为分散介质，有机酸阴离子与煅烧后的锌铝类水滑石的物质的量之比为1∶9的条件下，实现了苯甲酸及苯二甲酸异构阴离子与锌铝类水滑石的插层反应，同时，还进行了等物质的量的两种酸与锌铝类水滑石（1∶1∶9）的插层反应。利用XRD和IR测试技术对样品结构进行表征，UV及HPLC对有机酸的反应量进行定量，并采用Gaussian-98软件包中ab initio分子轨道法（HF/6-31G）计算了各有机酸阴离子的分子结构，分析了其结构与插层行为的关系，并理论结合实验给出了各有机酸阴离子在锌铝类水滑石层间可能的空间构型。研究结果表明，苯甲酸及苯二甲酸异构阴离子在插层过程中表现出选择性，其优先进入锌铝类水滑石层间的顺序是：对苯二甲酸>邻苯二甲酸>间苯二甲酸>苯甲酸，且锌铝类水滑石对对苯二甲酸表现出较高的选择性，是环境友好的分离方法。     

类水滑石及其杂多阴离子柱撑物的合成与表面酸性研究

合成了一些类水滑石和过渡金属取代型杂多酸盐，并由此制备了相应杂多阴离子柱撑水滑石层柱材料。用ＸＲＤ，ＩＲ和元素分析等手段对合成产物进行组成和结构表征，用ＮＨ３－ＴＰＤ，Ｐｙ－ＩＲ研究了合成产物的表面酸性和酸类型，并在异丙醇反应中考察了合成物的酸碱催化行为，结果表明，水滑石和柱撑水滑石均同时存在酸碱中心，且酸碱相对强度与柱阴离子类型密切相关。杂多阴离子进入水滑石层，同时改变了水滑石和杂多酸盐的酸强度     

NiAl类水滑石/皂石层状复合材料的制备及结构表征

以NiAl类水滑石和八面体片阳离子为Zn²⁺的皂石为前体，利用两前体层板带电荷的相反性和层间域离子的可交换性，在室温、常压的温和实验条件下，将带正电荷的类水滑石层板引入到带负电荷的皂石层间，首次合成出了一种新型层状复合材料——NiAl类水滑石/皂石层状复合材料。XRD、DTA、IR和²⁷Al MAS NMR的测试结果表明，类水滑石八面体层板已顺利插层到皂石片层之间，复合材料在c轴方向是单个皂石层板与单个类水滑石层板的交叉堆叠。DTA分析结果还表明，该层状复合材料具有高热稳定性，结构破坏温度高达837 ℃。     

过氧杂多阴离子型层柱化合物的合成、表征及催化活性

通过离子交换法,将含Zr过渡金属离子1,3取代钨硅、钨磷过氧杂多酸盐嵌入Zn2Al类水滑石中,获得了层柱化合物,并用XRD,IR,UV等手段对产物的结构进行了表征.结果表明过氧杂多阴离子进入水滑石层间后,水滑石的层间距从0.92增大到1.47 nm,且过氧链没被破坏.层柱化合物在酯化反应中显示优良的催化性能.     

阳离子掺杂水滑石的制备及其性质研究

研究了掺杂阳离子水滑石的制备及阳离子对水滑石性质的影响. 分别制备了掺杂Zn2+、Ni2+、Fe3+型的水滑石, 考察了掺杂阳离子对水滑石晶相结构、层间距、层间阴离子含量、水滑石表面形态、水滑石碱性的影响, 结果表明, 由于阳离子的引入, 导致水滑石层间距减小及层间阴离子结合量降低, 且使水滑石培烧产物电负性提高, 并最终降低其碱性. 以上述水滑石培烧产物作为固体碱催化剂促进苯甲醛和丙醛缩合, 合成α-甲基肉桂醛, 关联了水滑石培烧产物碱性与反应活性的关系.     

Effect of temperature on carbon-black agglomeration in hydrocarbon liquid with adsorbed dispersant

Suspensions of carbon black in oil, stabilized with adsorbed polyisobutylene succinimide (PIBSI) dispersant, are commonly used as model systems for investigating the soot-handling characteristics of motor oils. The structure of the carbon-black agglomerates changes dramatically with temperature; this results in a concomitant change in the suspension rheology. Linear and nonlinear rheological experiments indicate a large increase of the interparticle attractions as the temperature is raised. To elucidate the origin of this behavior, we investigate the effect of temperature on the stabilizing effect of the dispersant. Measurements of adsorption isotherms of the dispersant on carbon black indicate that there is little variation of the binding energy with temperature. Intrinsic viscosity measurements of PIBSI dispersants in solution clearly exhibit an inverse dependence of the dispersant chain dimension with temperature. These results suggest that the temperature-dependent changes in the chain conformation of the PIBSI dispersant are primarily responsible for the changes in the dispersion rheology, and we propose a simple model to account for these data.     

表面活性剂对氧化锰悬浮体系流变学振荡行为的影响

对介孔氧化锰的溶胶-凝胶法合成和用表面活性剂（脂肪醇聚氧乙烯醚, AEO_9)的模板合成过程中所得的悬浮体系的流变性质进行了对比研究。结果表明： 上述体系均具有触变性,且无论是否预剪切,其表观粘度均随时间作周期性振荡; 同时上述体系的储能模量G'和损耗模量G"亦具有周期性的振荡行为。但表面活性剂 AEO_9的引入使体系的触变性大为减弱,屈服值明显降低,凝胶结构强度减弱。同 时还发现引入AEO_9的模板合成过程中,不仅体系的表观粘度及G'大幅度下降,且 G'与G"的振荡周期显著增大,振幅亦明显减小。这说明体系中两亲分子与无机物存 在较强的相互作用,作者还对这些现象进行了讨论。     

AN/St悬浮共聚体系中AN在水/油两相间分配及其对共聚物组成的影响

研究了丙烯腈/苯乙烯(AN/St)悬浮共聚体系中AN在水/油两相间的分配及其对AN/St共聚物组成的影响.结果表明,AN分配于水/油两相间,使油相AN的含量低于相同单体配料比的本体聚合,导致生成的AN/St共聚物组成偏离本体共聚.为了准确预测进而控制AN/St悬浮共聚物的组成,提出了在考虑AN相分配的基础上计算AN/St悬浮共聚物组成的模型.计算结果与实验值一致,计算中用到的油相实际竞聚率与本体聚合相同,但该悬浮聚合的表观竞聚率随水/油比的变化而发生较大改变.     

单一化学交联与物理化学复合交联高吸油树脂的比较

提出在单一化学交联吸油树脂中引入物理交联的设想，并采用悬浮聚合法了单一化学交联和物理－化学复合交联的聚丙烯酸酯系高吸油树脂，对两种不同树脂的吸油速率，低亲油性单体树脂的吸油性能，最佳单体配比以及化学交联剂含量的影响进行了比较，结果表明物理交联的引入加快了树脂的吸油速率，提高低亲油性单体树脂的吸油能力，并且还使最佳单体配比中低亲油性单体含量增加，同时表明部分物理交联吸油树脂有一最佳化学交联剂含量区。     

漂浮法制备SiO2有序大孔材料

用漂浮组装方法以亚微米尺度单分散的聚苯乙烯(PS)微球作为模板, 在悬浮液气-液界面处组装PS模板微球与纳米级胶体颗粒, 形成二元胶体颗粒共混物, 再去除模板得到有序大孔材料.     

Structural characterization of ultrasmall superparamagnetic iron oxide (USPIO) particles in aqueous suspension by energy dispersive X-ray diffraction (EDXD)

Ultrasmall superparamagnetic iron oxide (USPIO) particles were structurally characterized in situ in an aqueous dilute suspension by energy dispersive X-ray diffraction (EDXD) and ex situ as powders obtained by lyophilization of the suspension by angular dispersive X-ray diffraction (ADXD) at 20 degrees C. Structural parameters obtained by the Rietveld method on ADXD data were used as starting parameters for modeling the structure of the particles in suspension. Although each particle is a single crystal, as evidenced by conventional X-ray diffraction, our results indicate that the structural order, specific to a crystal, does not extend to the entire volume of the particle. In fact, each individual particle, averagely, has a crystalline structural extension ca. 4.0 nm smaller than the apparent dimensions obtained by both ADXD and TEM (ca. 8.0 nm).     

石蜡或聚丁二烯填充型高吸油树脂的合成及其性能比较

以过氧化二苯甲酰 (BPO)为引发剂、二甲基丙烯酸乙二酯 (EGDMA)为化学交联剂、甲基丙烯酸十二酯 (DMA)和苯乙烯 (St)为单体、石蜡 (Paraffin)或聚丁二烯 (PB)为填充剂 ,用悬浮聚合法合成了填充型高吸油树脂 .研究了单体配比、填充剂用量以及化学交联度对树脂吸油性能及凝胶分率的影响 .对石蜡和PB填充的高吸油树脂进行比较 ,发现PB填充的高吸油树脂中存在物理交联 ,而石蜡填充的树脂中不含物理交联 ;PB填充的高吸油树脂随PB用量的增加 ,吸油倍率提高 ,凝胶分率上升 ,脱油速率增大 ;而石蜡填充的树脂随石蜡用量的增加 ,吸油倍率提高 ,但凝胶分率和脱油速率变化不大     

Effects of acrylonitrile water solubility on limiting conversion and copolymer composition in suspension polymerization

The effects of acrylonitrile (AN) water solubility on the limiting conversion and copolymer composition of the AN and AN/vinylidene chloride (VDC) suspension polymerization were investigated. It was found that AN dissolved in aqueous phase does not transfer back to oil phase in AN suspension homopolymerization but partially does in AN/VDC suspension copolymerization, and thus the limiting conversion is lowered and decreases with water/oil ratio increasing in both AN and AN/VDC suspension polymerization. For the continuous transport of AN in aqueous phase to oil phase during suspension polymerization, the composition distribution of AN/VDC copolymer prepared by suspension polymerization is narrower than that by bulk polymerization. The calculated composition of AN/VDC suspension copolymer with considering AN water solubility is consistent with the experimental data.     

Oral Bioavailability of Flutamide from 1‐O‐Alkylglycerol Stabilized o/w Nanoemulsions

Size of oil globule and emulsifier film covering it are the key factors modifying oral absorption of drugs dissolved/dispersed in oil globules of o/w emulsions. Since oral bioavailability of flutamide (FTM) is poor, nanoemulsions incorporating FTM in oil phase and globules stabilized by a novel lipophilic emulsifier, 1‐O‐alkylglycerol were developed and characterized. All nanoemulsions had a size around 200 nm. They exhibited considerable release retardation in vitro. Flutamide nanoemulsions were evaluated for oral bioavailability in rabbits and in situ intestinal absorption in rats. Serum level data of flutamide obtained in the in situ experiments indicate higher FTM absorption from nanoemulsions than the aqueous FTM suspension. Among the nanoemulsions, 1‐O‐alkylglycerol stabilized systems showed higher absorption. The results of bioavailability studies in rabbits indicate increased absorption and decreased elimination of FTM from nanoemulsions, thus improving the bioavailability. Increased rate of absorption of flutamide in the in situ experiments can be attributed to the permeation enhancement effect of 1‐O‐alkylglycerols. However, size of the oil droplet seems to be the major factor in improving oral bioavailability in rabbits.     

Synthesis of reusable macroporous St/BMA copolymer resin and its absorbency to organic solvent and oil

In this paper, a reusable macroporous high oil absorption resin for oil spills was synthesized successfully by suspension copolymerization with styrene and butyl methacrylate as monomers. In the process of suspension copolymerization, a porogenic agent was introduced into the reaction system. Structure and surface morphology of the macroporous resin were characterized by Fourier transform infrared spectrometry, X‐ray photoelectron spectroscopy, and scanning electron microscopy. In addition, effects of different reaction factors on density and particle size of macroporous resins and effects of various factors on the oil absorbency of macroporous resins were discussed. Furthermore, oil absorption kinetics and repeatability of resin and the absorbency of the macroporous resin in various oils were also studied. Compared with the resin without macroporous structure, the maximum oil absorbency of the macroporous resin to the carbon tetrachloride (CCl₄) was 28.28 g/g, which increased by 61.42%. Meanwhile, the saturated oil absorption time of resin also decreased significantly from 7.5 to 2 hr. The macroporous high oil absorption resin presents predominant performance of reuse and regeneration. Moreover, the macroporous resin had certain absorbency (8.7 g/g) to crude oil, which makes it useful for marine oil spill. Copyright © 2015 John Wiley & Sons, Ltd.