氯代纤维素的制备及其性质的研究

本文用氯化锂／二甲基乙酰胺（LiCl/DMAc）作溶剂在均相条件下制备了氯代纤维素，研究了影响氯代反应速率的若干因素，讨论了产品的若干性质。研究发现，在氯代反应过程中存在两种取代反应，一个是氯原子取代，另一个是乙酰基取代。取代基的位置主要集中在葡萄糖基的第六位碳原子（C_6）上。纯的氯代纤维素仅溶解在DMAc中，而带有少量乙酰基的氯代纤维素则可以溶解在甲醇、乙醇、丙酮以及DMAc等溶剂中。在氯代纤维素的DSC曲线上有两个峰，一个是吸热峰，而另一个是放热峰。     

高岭石/丙烯酰胺插层复合物的微波制备及其表征

高岭石及其有机插层复合物在高性能陶瓷领域有着良好的应用前景。本文利用微波技术,以DMSO作为前驱体,制备高岭石/丙烯酰胺插层复合物,发现微波对丙稀酰胺的插层反应具有相当明显的促进作用,反应时间从通常的几天缩短到几个小时。采用X-射线衍射、FT-IR光谱、TG等技术对其进行表征。结果表明:反应2小时后,该插层复合物的层间距即可扩大为1.139nm,其键合方式发生了改变,形成新的氢键。这为工业生产高岭石有机插层物以及制造纳米级高岭土提供了高效的新途径,并为进一步生产高性能陶瓷方面打下了基础。     

Fe-膨胀石墨插层复合物EGIC的制备与表征

用熔盐法合成了FeCl3膨胀石墨层间化合物（FeCl3-EGICs）,并对I阶结构的FeCl3-EGICs进行了混合气氛下的还原反应,得到了含有单质铁的膨胀石墨插层复合物Fe-EGIC,其特征层间距为0.587-0.588nm。对还原前后的插层复合物进行了阶结构、热性能、电性能的表征与分析。发现FeCl3-EGIC在空气中具有良好的结构稳定性,及在受热环境中具有较高的热稳定性,并通过电导率测试发现,所制备的插层复合物的电导率较原始石墨有所提高。     

β-环糊精/聚乙二醇复合物的制备及表征

将β-环糊精与数均分子量1000的聚乙二醇(PEG)在65℃水中进行共混形成复合物。利用1 H NMR、XRD、纳米粒度分析、DSC、SEM等方法对形成的复合物进行表征,1 H NMR分析表明复合物中β-环糊精与PEG的摩尔比为7.5∶1;XRD分析表明复合物中PEG的存在改变了β-环糊精的晶形;纳米粒度分析表明复合物中PEG的存在会减小β-环糊精聚集体的粒径;DSC测试表明复合物中PEG分子呈无定形状态。     

石墨嵌入复合物的制备及其应用

本文对有关石墨嵌入复合物（GIC）的基本概念、合成方法以及石墨嵌入复合物的性能及应用情况进行了综述。     

氧化铁／氧化镁复合物及用此复合物分解氯代烃的方法

介绍了一些精细的复合物,它们是由一种金属氧化物组成,且至少部分涂敷有一薄层另一种金属氧化物。该复合物表面积大,用于分解吸附气态或液态物液中的不良流体时非常有效,如氯代烃和氯氟烃。在使用过程中,将含有不良流体的物流与本发明中的复合物接触,例如使用装有该复合物的过滤器,使复合物作为过滤介质的一部分。     

高岭石/苯甲酰胺插层复合物的制备与表征

以高岭石／二甲亚砜作为前驱物,用熔融插层法成功制备了高岭石／苯甲酰胺插层复合物,产物用X射线粉晶衍射和Fourier变换红外光谱进行了表征。实验结果表明：高岭石／苯甲酰胺插层复合物中,高岭石的层间距扩张到1.428nm,插层率达到了82．5％;苯甲酰胺分子的氨基与高岭石的内表面羟基形成了氢键,苯甲酰胺分子可能以单分子层垂直排列于高岭石层间。高岭石／苯甲酰胺插层复合物在140～180℃的温度范围内,会发生苯甲酰胺的脱嵌过程。     

羟基磷灰石-明胶复合物的制备及表征

对均相沉淀法制备HAP-GEL粉体及溶胶进行了研究,结果表明:采用均相沉淀法可以制得小尺寸且分布均匀的颗粒;HAP-GEL溶胶可以稳定三个月以上;热分析图谱及TEM照片表明,在HAP-GEL结构中HAP微晶和GEL高分子产生了键连作用,且HAP沿着GEL纤维上呈现自组装结构。初步探索了Ca∶P、pH值、温度、搅拌强度、滴加速度、超声时间对产物性能、尺寸及稳定性的影响。采用琼脂糖凝胶电泳和钙红染色法对制备的HAP-GEL作了表面电位定性测试。     

原位乳液聚合聚苯胺/聚甲基丙烯酸甲酯复合物及其表征

以DBSA为乳化剂和掺杂剂,在水介质中采用原位乳液聚合法制备出了聚苯胺/聚甲基丙烯酸甲酯(PANI/PMMA)复合物。采用扫描电镜、红外光谱分析、紫外光谱分析、热失重分析、X射线光电子能谱分析对PANI/PMMA复合物进行了表征。结果表明:复合物产物粒径在80～120nm;电导率可达到10-2S/cm,接近于乳液聚合得到的DBSA掺杂态PANI;乳化剂DBSA以掺杂剂和稳定剂两种状态存在于复合物中。     

丙烯酸乳液/TiO_2纳米复合物的制备与表征

采用四种方法制备了聚丙烯酸 /TiO2 纳米复合乳液。通过TEM研究了纳米TiO2 在聚丙烯酸涂膜中的分散状况 ,以及考察了纳米TiO2 /聚丙烯酸膜的力学性能和光学性能。     

超疏水金红石型纳米钛硅复合氧化物的制备与表征

以正硅酸乙酯为硅源、钛酸异丙酯为钛源,采用改进的溶胶-凝胶法制备了不同钛硅摩尔比的复合气凝胶,在不同温度下进行煅烧,得到金红石型钛硅（TiO₂-SiO₂）复合氧化物纳米颗粒,然后通过三甲基氯硅烷（TMCS）改性,制得超疏水金红石型TiO₂-SiO₂纳米材料。探讨了钛硅摩尔比和煅烧温度对钛硅复合氧化物纳米颗粒晶型的影响,并通过XRD、XPS、BET、SEM和FTIR等手段对产物进行了表征,采用水接触角测试（WCA）对纳米材料改性后的疏水性能进行了表征。结果表明：当钛硅摩尔比为5：1时制得的气凝胶在1100℃煅烧及TMCS改性后,所制备的超疏水金红石型纳米钛硅复合氧化物的比表面积大,疏水性能优异,其比表面积达348 m²·g^-1,水接触角达到154.7°,在构建具有纳微分层结构的外墙装饰材料的面漆方面具有潜在的应用前景。     

Preparation and characterization of alginate–carrageenan complex films

Alginate–carrageenan (Al–Ca) complex films were synthesized and characterized. The Al–Ca ratio and the crosslinking agent type were important factors in determining the pore size of the complex film. The pore size decreased with an increasing carrageenan content and was reduced further by a crosslinking reaction with CaCl₂. The most uniform and flexibile film was formed at an Al–Ca ratio of 6:4. The degree of swelling of crosslinked films increased with an increasing carrageenan content. With a combination of CaCl₂ and ZnSO₄, the water content of the film due to swelling was smallest, which was more suitable than with CaCl₂ alone. The permeabilities of glucose and dextrans for Al–Ca complex films increased as the alginate content increased, because complex films with a high alginate content had large pores. The partition coefficients of glucose and dextrans for films were in a range of 0.2 to 1.0 depending on the contents of alginate and carrageenan. A 6:4 Al–Ca complex film was most stable in a phosphate buffer solution, indicating that the 6:4 content ratio was suitable to maintain the mechanical strength of alginate–carrageenan chains. © 2006 Wiley Periodicals, Inc. J Appl Polym Sci 99: 3483–3490, 2006     

羧化淀粉/PVA复合水凝胶的制备与性质研究

由顺丁烯二酸酐羧化的淀粉与聚乙烯醇按比例进行溶液混合,经冷冻-解冻形成物理交联复合水凝胶。采用WAXD和DSC分析了复合凝胶的结晶性和热性能,探讨了羧化淀粉的含量及其取代度对凝胶结构和溶胀性质的影响。结果表明,羧化改性增强了淀粉与PVA的相互作用,复合水凝胶的稳定性和溶胀性取决于羧化淀粉的质量分数及其取代度。     

低温条件下纳米腐殖酸-尿素配合物的制备及表征

为确定纳米腐殖酸-尿素配合物形成工艺参数和物化性质,以纳米腐殖酸和尿素为原料,通过络合反应制备了70~90 nm腐殖酸-尿素配合物,用响应面法优化制备纳米腐殖酸-尿素配合物最佳工艺参数为:反应温度47.6℃,反应时间1.81 h,活化剂十二烷基硫酸钠浓度50.0%(质量),固液体摩尔比9:1,络合剂浓度0.14 mol·L^-1,尿素用量200 mg,产率预测值91.2%, 此条件下进行3组独立实验,产物产率为90.6%±0.9%,与模型的预测值吻合。拟合出响应值和影响因子间的二次关联方程模型。并用X射线衍射仪(XRD)、红外光谱仪(FTIR)、热重分析仪(TG)、扫描电镜(SEM)与吸附-脱附比表面仪(BET)等物理手段对产物晶型、组分、形貌大小及比表面积等进行表征。结果表明:配合物晶型完整纯度高,粒度大小均匀且分散性良好,粒径为70~90 nm,比表面积189.85 m²·g^-1,平均孔径10.2 nm,孔容0.86 cm³·g^-1,具有较高热稳定性。     

双金属氰化物络合物催化剂的制备、表征与催化性能研究

分别以PEG-1000、β-环糊精和吐温-60等为助络合剂,采用不同工艺方法制备了具有不同结构的双金属氰化物络合物(DMC)催化剂,研究了不同助络合剂和不同制备方法对DMC催化剂的形貌、粒径、晶型结构和催化活性的影响.结果表明以PEG-1000、β-环糊精和吐温-60等为助络合剂,利用传统制备方法可以获得晶态与非晶态组分混合物的DMC催化剂.而将助络合剂提前加入到钾盐和锌盐溶液中,可制备出高度分散的非晶态的DMC.这种非晶态的DMC催化剂活性高,反应速度快,其催化性能明显优于利用传统制备方法制备的DMC.     

Preparation and characterization of complex gel of type I collagen and aluminosilicate containing imogolite nanofibers

Complex gel materials of Type I collagen and aluminosilicate containing imogolite nanofibers were prepared as opaque gel by mixing an acidic fine dispersion of aluminosilicate with an acidic solution of collagen. The product was stained blue by Coomassie Brilliant Blue (CBB), indicating that the gel contained collagen. A white sponge was obtained after lyophilization of the complex gel. Elemental analysis revealed that the complex contains C, H, N, Al, and Si atoms; and the compositional ratio of aluminosilicate/collagen (w/w) was calculated as 0.75 for the complex gel when aluminosilicate was mixed with an equal quantity of collagen. Transmission electron microscope (TEM) observation showed that aluminosilicate nanofibers were homogeneously distributed in the collagen matrix. The thermogravimetric analysis (TGA) curve of the complex was not a simple summation of each components, and especially, the weight loss step corresponding to detachment of the adsorbed water observed in aluminosilicate became difficult to distinguish, suggesting that the adsorbed water was removed in the complexation. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

Preparation, characterization and bifunctional electrocatalysis of an inorganic-organic complex with a vanadium-substituted polyoxometalate

An inorganic-organic complex with a vanadium-substituted polyoxometalate 1, formulated as [Cu(phen)₂]₂PVW₁₁O₄₀ was hydrothermally synthesized. Complex 1 crystallizes in the monoclinic P2(1)/c space group with a = 25.9932(12) Å, b = 11.9889(6) Å, c = 23.2672(11) Å, β = 113.6750(10)°, V = 6640.5(6) Å³, R = 0.0312, and Z = 4. Complex 1 is constructed from a Keggin-type anion PVW₁₁O₄₀⁴⁻ coordinated to two [Cu(phen)₂]²⁺ units. One [Cu(phen)₂]²⁺ unit is coordinated to a terminal oxygen and the other [Cu(phen)₂]²⁺ unit is coordinated to a bridging oxygen of the polyoxoanion. Redox activities for both the tungsten and vanadium centers have been observed using cyclic voltammetry performed on 1-bulk modified carbon paste electrode (CPE). It was found that 1 presents good electrocatalytic activities not only for the reduction of IO₃⁻, NO₂⁻, and H₂O₂ but also the oxidation of l-cysteine. Complex 1 also shows intense luminescent properties arising from ligand-to-copper charge transfer and oxygen-to-vanadium charge transfer at room temperature in the solid state.     

Stoichiometric and nonstoichiometric polyelectrolyte complex of chitosan and polyethyleneglycol‐monosuccinate: Preparation and characterization

Stoichiometric and nonstoichiometric polyelectrolyte complex (PEC) was prepared with polyethylene glycol‐monosuccinate (PEGMS), and chitosan (CS). A series of PEGMS were synthesized by a 1 : 1 mol ratio between PEG and succinic anhydride. Then, the novel PEC was prepared by a various mole reaction of the above synthesized PEGMS and CS. The physicochemical properties of the synthesized PEC was characterized by using elemental analysis, FTIR, ¹H, and ¹³C nuclear magnetic resonance, dissolution behavior, and phase transition phenomenon. Furthermore, some properties of the PEC obtained were analyzed by UV‐Visible spectrometry, wide‐angle X‐ray diffraction, differential scanning calorimeter, scanning electron microscope, and estimated solubility, and cell viability assay, respectively. It was found that the observed FTIR, ¹H, and ¹³C‐NMR data was in good agreement with the chemical structure of the prepared PEGMS and PEC. The dissolution behaviors of nonstoichiometric PEC were found to depend on the pH of the solution as well as on the PEGMS/CS composition. The study of MTT assay suggested that the viability of HepG2 human hepatoblastoma cell on PEC were increased significantly in accordance with mole ratio of CS. As the results, the obtained several product is a useful intermediate, which permits further chemical modification for the amino group of CS and may have potential applications in biocompatible or cosmetic systems. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 2007     

Microwave Promoted Alkylation of Halonitrobenzene with Malonates in Solvent-free Medium

Abstract The alkylations on different substituted halonitro benzenes have been demonstrated with various malonates under the influence of microwaves irradiation. The reactions were catalyzed by potassium carbonate and benzyltriethylammoniumchloride. The salient features of this methodology are mild reaction conditions, high regio-selectivity, rapid conversions, solvent-free medium and easy isolation of products Graphical abstract Microwave Promoted Alkylation of Halonitrobenzene with Malonates in Solvent-free Medium Venkat Narsaiah Akkirala      

羟基磷酸铁铵的制备与表征

采用硫酸亚铁和磷酸为原料,在尿素存在的条件下,水热合成得到高纯度的羟基磷酸铁铵。研究发现,反应温度不同得到的羟基磷酸铁铵的结晶度会有所不同,形貌差异较大。利用XRD、SEM、TG-DTA和红外分析等手段对制备的样品组成、结构、晶型和形貌做分析表征,分析了羟基磷酸铁铵在加热过程中的相变过程。结果表明,在静态羟基磷酸铁铵中,磷酸和铁具有固定的化学计量比,经高温煅烧后得到高纯度磷酸铁,可应用其制备锂离子电池正极材料磷酸铁锂的前驱体,且此法合成工艺简单,具有良好的工业应用潜质。