P123对聚醚砜纳米纤维膜结构和性能的影响

通过静电纺丝法制备了聚醚砜(PES)/聚环氧乙烷-聚环氧丙烷-聚环氧乙烷三嵌段共聚物(P123,PEO₂₀PPO₇₀PEO₂₀,M_a=5800)纳米纤维膜,考察了P123含量对纺丝液的黏度和表面张力的影响,以及对所制备的纳米纤维膜的结构和性能的影响。实验结果表明:P123含量从3%(质量)增至9%时,其纺丝液的黏度由300 mPa·s增至1000 mPa·s,表面张力在36.5～37.8 mN·m^-1范围内;P123改性的PES纳米纤维直径约为360 nm,分布均匀,其表面也比较光滑,取向趋于一致;此外,该纳米纤维膜具有良好的机械性能和耐溶胀性能,较大的比表面积(>39 m²·g^-1),孔隙率,可用作催化剂载体。     

基于偏氯乙烯嵌段共聚物的多级多孔炭的制备

采用可逆加成-断裂链转移（RAFT）活性自由基聚合制备了聚苯乙烯-b-聚偏氯乙烯-b-聚苯乙烯嵌段共聚物（PS-b-PVDC-b-PS）,以此嵌段共聚物为碳前驱体,直接碳化制备微孔-中孔复合多级多孔炭。采用凝胶渗透色谱仪和核磁共振仪表征了嵌段共聚物结构,表明通过RAFT聚合可制得分子量较高（M_n^GPC >6000 g·mol^-1）和分子量分布较窄（PDI<1.5）的PS-b-PVDC-b-PS。采用热重分析表征嵌段共聚物热解特性,采用扫描电镜、N₂吸脱附表征多孔炭形貌和孔隙结构。结果表明嵌段共聚物同时具有PVDC和PS链段的热失重峰,PS链段可完全热解而具有形成中孔的模板作用,PVDC链段热降解形成含微孔的炭骨架,最终形成兼有微孔和中孔的多级多孔炭;随着PS嵌段含量的增加,嵌段共聚物的成炭率逐渐降低,孔隙尺寸逐渐增大;当PS/PVDC聚合度比为4.3时,多孔炭的比表面积、中孔率和平均孔径达到最大,分别为839 m²·g^-1、54%和2.02 nm。     

有序介孔碳材料的模板化构筑及水处理应用研究

介孔碳材料是指孔径介于2 nm-50 nm的一类多孔碳材料。有序介孔碳材料，具有比表面积高、孔道结构规则有序、孔径分布狭窄、孔径大小可调控、表面易于修饰等结构特点和高机械强度、强吸附能力、化学惰性等性能特点，在诸多领域得到了广泛应用，特别是其作为新型吸附剂在水处理领域具有广阔的发展前景。有序介孔炭材料的制备方法主要有硬模板法和软模板法。模板和碳源的选择是控制有序介孔碳材料结构和性能的关键因素。本文从有序介孔硅、天然矿物、MOFs材料、嵌段共聚物等不同模板的角度对有序介孔碳、多级有序微/介孔碳、多级有序大/介孔碳的制备方法进行综述，并对有序介孔碳材料在水处理领域的应用进行简单介绍。     

有序介孔聚合物的研究进展

综述了以自组装法、硬模板法和软模板法合成有序介孔聚合物及介孔碳的研究进展。对上述3种制备方法及原理进行了比较,指出目前以嵌段共聚物进行自组装以及采用软模板法制备介孔聚合物的途径更有利于制备有序的介孔聚合物及介孔碳。讨论了采用自组装法及软模板法时,嵌段共聚物的种类、模板剂的类型、聚合物前躯体的结构等对所制备的介孔聚合物以及介孔碳的形貌、介孔结构、骨架结构以及介孔材料的物理化学性能的影响。指出目前在介孔聚合物以及介孔碳的研究中,主要问题是如何提高介孔聚合物的有序性以及其介孔结构的稳定性。最后对有序介孔聚合物及介孔碳的发展方向及应用领域进行了展望。     

不同模板剂对介孔SiO2-TiO2复合材料光催化性能的影响

介孔材料被用于光催化领域。利用不同类型的模板剂调节孔径和比表面积是提高光催化效率的方法之一,在介孔材料中引入第二金属或金属氧化物也是提高其降解效率的有效途径。因而,选用阳离子表面活性剂N-十六烷基乙二胺(HEDA)、非离子表面活性剂三嵌段共聚物EO_(20)PO_(70)EO_(20)(P123)与EO_(106)PO_(70)EO_(106)(F127),分别合成相应的介孔材料;通过静电作用将TiO_2负载到介孔材料表面及内部,制备介孔SiO_2-TiO_2复合材料。研究不同离子型模板剂对介孔材料的比表面积及光催化降解效率的影响。     

软模板法合成有序介孔炭的模板剂研究进展

本文较为详尽地介绍了软模板法合成有序介孔炭材料过程中常用到的几种模板剂,包括两性表面活性剂、嵌段共聚物等,其中嵌段共聚物又可进一步划分为二嵌段共聚物和三嵌段共聚物.并简要介绍了合成介孔炭时采用的反应路线以及产物的结构特征.比较了不同模板剂在合成过程中的优缺点,并展望了其未来发展前景.     

添加乙醇水热法制备介孔氧化铝及其吸附性能的研究

引用嵌段共聚物作软模板剂和乙醇作结构调节剂来制备介孔氧化铝,结合XRD、SEM、N2吸附对的产物形貌、比表面积、孔容、孔径进行分析。通过UV紫外分光光度计检测样品对有机污染物(如刚果红)的分离能力。     

高比表面积硼掺杂有序介孔炭的制备

以低分子量硼掺杂酚醛树脂(BPF)为炭前驱体、正硅酸四乙酯(TEOS)为无机前驱体、嵌段共聚物F127(PEO_(106)PPO_(70)PEO_(106))为软模板,采用溶剂挥发诱导自组装法(EISA)合成具有高比表面积、高硼含量的硼掺杂有序介孔炭(BOMC)。利用傅里叶变换红外光谱仪、X射线光电子能谱仪、X射线衍射仪、氮气吸-脱附仪、透射电子显微镜对硼掺杂有序介孔炭的组成、结构及形貌等进行表征。结果表明,制得的硼掺杂有序介孔炭材料具有高度有序的二维六方介观结构,其比表面积和硼含量分别高达891.17 m2/g和1.36%,孔径为5.5 nm。     

软模板法用壳聚糖制备富氮多孔碳材料

以壳聚糖溶液为原料、三嵌段两亲共聚物F127为软模板,采用一步法合成多孔碳氮材料,考察了复配溶液pH值及碳化温度等条件对材料孔结构、比表面积和吸附CO2的影响. 结果表明,材料以介孔为主,比表面积最高达457 cm2/g,氮含量最高达7.60%,表面氮元素含量最高达8.45%,以吡啶类活泼价态形式存在,材料对CO2的吸附量最高达80.8 mg/g,吸附效率达0.274 mg/cm3.     

原位合成有序介孔氧化铝负载Cu-Ce催化剂及其维埃斯吸附消毒性能

以三嵌段共聚物F127(EO₁₀₆PO₇₀EO₁₀₆)为模板剂,Al[OCH(CH₃)₂]₃为铝源,活性组分前体Cu(NO₃)₂·2.5H₂O和Ce(NO₃)₂·6H₂O,采取原位合成法制备有序介孔氧化铝负载的Cu-Ce催化剂,研究合成的有序介孔氧化铝及催化剂对维埃斯(VS)的消毒效果。结果表明,VS在Al-0.05Cu-0.05Ce双金属催化剂表面的消毒降解效果最佳,产物中氧化物相对较多,主要发生S—C键和P—S键的断裂,断裂的碎片进一步氧化,反应4天,VS消毒降解率98.01%。这可能是由于CeO₂中的铈元素能受环境影响在Ce³⁺→Ce⁴⁺间发生可逆转变,催化VS发生氧化消毒反应。     

Fabrication of three-dimensional ordered macroporous/mesoporous magnesium oxide for efficient cadmium removal

Cadmium (Cd) is a hazardous heavy metal, that poses a serious threat to human health. Magnesium oxide has shown excellent adsorption performance for the removal of Cd(II) from contaminated wastewater. Herein, three-dimensional ordered macroporous/mesoporous MgO (3DOM/m MgO) was synthesized by a double template method using amphiphilic triblock copolymer Pluronic F127 as the soft template and polystyrene colloidal crystal as the hard template. Compared with three-dimensional ordered macroporous MgO (3DOM MgO), 3DOM/m MgO exhibited a macro/mesoporous structure with a larger specific surface area (96.94 m²/g). The maximum adsorption capacity of 3DOM/m MgO reached 2933 mg/g for the removal of Cd(II) removal from an aqueous solution. BET and XPS analyses results revealed that the enhanced Cd(II) adsorption capacity of 3DOM/m MgO was attributed to its large specific surface area and the complexing ability of its hydroxy groups. The adsorption performance of 3DOM/m MgO was investigated by batch adsorption experiments, including adsorption isotherms and adsorption kinetics. 3DOM/m MgO completely removed 100 mg/L Cd(II), with a removal efficiency ≥99.9%. The adsorption behavior followed the pseudo-second-order kinetic model and Langmuir isotherm model, which revealed that the adsorption of Cd(II) on 3DOM/m MgO proceeded via homogeneous chemisorption. Due to its advantages of controllability and excellent adsorption performance, 3DOM/m MgO is a promising adsorbent for the removal of Cd(II) from polluted water.     

Ni_xMg_（1-x）O固溶体的合成及其催化乙醇转化制氢的研究

以CMK-3为硬模板,通过浇铸方法制备介孔固溶体NixMg1-xO。考察了前驱体溶液的浓度、溶剂、灌制方法、灌制次数和模板脱除温度等因素,对合成产物物理性质的影响。结果表明,以浓度为0.8mol.L-1的硝酸盐乙醇溶液作为前驱体,超声波处理下灌制3次,以及在脱除模板的过程中,事先在650℃下Ar气环境中预处理待脱模板样品,之后于650℃高温焙烧,可得到具有介孔特性的NixMg1-xO固溶体。还原介孔固溶体NixMg1-xO所得的Ni/NixMg1-xO催化剂,与浸渍法、共沉淀法制备的Ni/MgO,Ni/NiO-MgO,Ni/MgO（介孔MgO载体）催化剂相比,在催化乙醇转化制氢中,具有最高的催化活性。     

Synthesizing nanocrystal-assembled mesoporous magnesium oxide using cotton fibres as exotemplate

A novel biomorphic nanocrystal-assembled mesoporous (NAM) magnesium oxides have been synthesized via an exotemplating pathway using cotton fibres as template and magnesium acetate as MgO precursor. These mesoporous MgO materials replicate the microtubular or zonal structure of the cotton morphology, and their frameworks are constructed by plenty of uniform MgO nanocrystals, which are different from those of the cotton template and reference MgO prepared by directly thermal-decomposition of MgO precursor. The mesoporous structure with narrow slit-like pores can be formed, if suitably chosen amounts of precursor magnesium acetate are used. These biomorphic NAM MgO materials have high surface areas, exhibit high selectivity in the catalytic decomposition of isopropanol, and display their potential for an effective basic catalyst or support.     

一种回收PVC门窗软硬共挤废料制备热塑性弹性体的方法

研究一种直接回收PVC软硬共挤门窗废料制备热塑性弹性体的方法。实验结果表明,添加一定的CPE(氯化聚乙烯)、DOP(邻苯二甲酸二辛酯)、碳酸钙等助剂,经加工改性后,由PVC门窗软硬共挤废料制成的热塑性弹性体力学性能可达到塑料门窗、客车门窗密封条的国家标准。     

介孔碳微球的合成及其应用研究进展

目前,介孔碳微球的合成主要有硬模板和软模板两种方法。硬模板是将碳前驱体通过溶剂挥发填充到已合成的球形介孔材料(硬模板)中,然后热处理掉硬模板得到介孔碳微球;软模板则是以三嵌段共聚物F127做为模板剂,酚醛树脂作为碳源在水热条件下制备出介孔碳微球。介孔碳微球在超级电容、锂离子电池、气体储存、生物医药等领域获得广泛应用,然而在摩擦润滑领域的研究却未见报道。结合本课题组的前期研究提出了其在摩擦领域的研究思路并展望了其应用前景。     

Study on the synthesis of poly(ether‐block‐amide) copolymer based on nylon6 and poly(ethylene oxide) with various block lengths

Various segmented block copolyetheramides based on nylon6 (N6) and poly(ethylene oxide) (PEO) with different compositions and block length of the hard and soft segments were synthesized. The effect of composition of the hard and soft segments was studied via FTIR spectroscopy based on the characteristic peak of ester group at wave number of 1730 cm^?1. The average block length of the hard and soft segments in block copolymers was determined from H‐NMR analysis. Differential thermal analysis thermograms confirmed a microphase separated morphology over a broad range of temperature, leading to two separated crystalline domains. An increase in the interconnectivity of the polyamide segments controlled by chain extension, greatly improved the formation of polyamide lamellae crystals determined by X‐ray diffractometry. Atomic force microscopy images indicated different morphologies of dispersed phase in the dominant phase, which plays an important role in their performance for membrane processes. © 2010 Wiley Periodicals, Inc. J Appl Polym Sci, 2010     

三维有序介孔和大孔过渡金属氧化物的硬模板制备及催化应用

总结了课题组以硬模板法制备三维有序介孔Cr2O3(3DOMeso-Cr2O3)、Co3O4(3DOMeso-Co3O4)、MnO2(3DOMeso-MnO2)、Fe2O3(3DOMeso-Fe2O3)和三维有序大孔Fe2O3(3DOMacro-Fe2O3)及其催化氧化挥发性有机物的研究进展。以三维有序介孔二氧化硅KIT-6为硬模板,可制备出3DOMeso-Cr2O3-1、3DOMeso-Cr2O3-2、3DOMeso-Co3O4-1和3DOMeso-Fe2O3,比表面积分别为106、124、121、113 m2/g;以三维有序介孔二氧化硅SBA-16为硬模板,可制备出3DOMeso-Co3O4-2、3DOMeso-Co3O4-3和3DOMeso-MnO2,比表面积分别为118、313、266 m2/g;以规整排列的聚甲基丙烯酸甲酯微球为硬模板,可获得3DOMacro-Fe2O3,比表面积为42 m2/g。这些三维有序介孔或大孔结构的过渡金属氧化物对典型挥发性有机物(甲苯、甲醛、甲醇、丙酮和乙酸乙酯)氧化反应显示出优异的催化性能。     

A novel synthesis method of hierarchical mesoporous MgO nanoflakes employing carbon nanoparticles as the hard templates for photocatalytic degradation

We describe a novel synthesis method for the preparation of bimodal mesoporous MgO nanoflakes and their application in photocatalytic activity for the degradation of methylene blue dye under UV light irradiation. For this purpose, Mg(OH)₂/carbon nanocomposite was obtained through the precipitation of magnesium hydroxide in the presence of carbon nanoparticles. X-ray diffraction pattern (XRD), scanning electron microscopy (SEM), and transition electron microscopy (TEM) micrographs have shown that this strategy could be successfully used to prepare bimodal mesoporous MgO nanoflakes with two different pore size distributions centered at 3 and 25 nm and a high specific surface area of 216.9 m²/g. Furthermore, the product was used as an adsorbent to remove methylene blue dye from aqueous media. The results confirmed that the photocatalytic activity of the synthesized mesoporous MgO was significantly improved due to the presence of such different pore sizes and high specific surface area resulting in higher adsorption, storage, and degradation of dye molecules.     

Synthesis and characterization of poly (ethylene oxide) containing copolyimides for hydrogen purification

Reverse selective membranes comprising poly(ethylene oxide) (PEO) containing copolyimides (PEO-PI) with variations of acid dianhydrides and diamines have been synthesized for hydrogen purification. The reverse selectivity of the membranes decimate the energy required for hydrogen recompression process. Factors including PEO content, PEO molecular weight, and fractional free volume (FFV) that would affect the gas transport performance have been investigated and elucidated in terms of degree of crystallinity, phase separation in the PEO domain as well as inter-penetration between the hard and soft segments. In mixed gas tests of CO₂ and H₂ mixtures, a highly condensable CO₂ out compete H₂ for the sorption sites in hard segment and diminishes H₂ permeability. Thus the CO₂/H₂ selectivity in the mixed gas tests is much higher than that in pure gas tests. Mixed gas permeation tests at 35 °C and 2atm show that the best reverse selective membranes have a CO₂ permeability of 179.3 Barrers and a CO₂/H₂ permselectivity of 22.7. The physical properties of PEO-PIs have also been characterized by FTIR, DSC, GPC, WAXS, AFM and tensile strain tests.