Macro and meso porous polymeric materials from miscible polysulfone/polyimide blends by chemical decomposition of polyimides

Novel macro and meso porous polysulfone materials were prepared from miscible blends of polysulfones with a phenylindane containing polyimide by selective chemical decomposition of the polyimide phase using a dilute hydrazine or tetraammonium hydroxide solution in methanol. It was found that the pore size of the material is affected by the backbone structure of the polysulfone selected. The compatibility between the polysulfones and the polyimide is influenced by the polysulfone structure. This in turn affects the pore size and the pore size distribution of the final porous material. Polyether sulfone was found to form most compatible blends that in turn leads to a porous material with the smallest pore size, a meso porous material. The meso porous polyether sulfones are transparent films, with uniform pore sizes in the range of 30 nm, while bisphenol A polysulfone based porous materials are opaque with pore sizes in the range of 200 nm.     

废润滑油脱色技术研究及应用进展

根据国内外废润滑油脱色技术的研究和应用情况,分析了废润滑油劣化成色机理,对以吸附法、加氢法、絮凝脱色法为主的废润滑油脱色技术进行了分析总结。从各类废润滑油脱色技术的脱色原理出发,结合具体的废润滑油脱色应用,评述了相关的废润滑油脱色技术的脱色效率、应用进展和存在的问题,并指出了废润滑油脱色技术需要进一步研究的问题和发展的方向。     

Development of reaction–diffusion DFT and its application to catalytic oxidation of NO in porous materials

The reaction–diffusion (RD) process is an important and complex subject that involves nonequilibrium modeling and multiscale calculations and may be applied to multiple fields. State-of-art theories are computationally too expensive for real-world applications. We propose a novel classical density functional theory (CDFT) for RD modeling by combining ordinary time-dependent density functional theory (TDDFT) and reaction kinetic models to examine the multiscale RD process. The theory is applied to NO oxidation in porous materials. The uptake, flux, and density profiles are examined, to reveal that the shape of the pore could influence the selectivity of adsorption between the reactant and product, which further leads to variations in the catalytic efficiency. It is noted that open pores are more favorable for catalytic reactions. The importance of adsorption is examined in the presence as well as the absence of pore–gas attraction. Without attraction, the catalytic efficiency is decreased by three orders of magnitude.     

多孔炭材料的制备及在废水处理中的应用研究进展

以微孔炭、介孔炭及大孔炭为代表的多孔炭材料,因其三维多孔结构和良好的热稳定性而具有优异的吸附性能,其主要制备方法有活化法、软硬模板法等。在介绍了三种多孔炭材料制备方法与特点的基础上,综述了多孔炭材料作为吸附剂在重金属离子废水、染料废水和其他废水处理中的应用研究进展。     

分级多孔碳的制备及其在超级电容器中的应用

超级电容器因其高功率密度、超高速充放电、高稳定性等突出特点在电化学储能装置中引起人们极大关注.在当前开发的电极材料中,碳材料因其良好的导电性、孔隙率及形貌可调等特点备受青睐.传统的单一微孔碳材料具有较大的比表面积,但存在利用率低、孔道堵塞、电阻较大等问题.针对上述问题,研究人员对分级结构多孔碳材料开展了广泛的研究.本工...     

Synthesis and characterization of new polysiloxane bearing vinylic function and its application for the preparation of poly (silicone-co-acrylate)/montmorillonite nanocomposite emulsion

A new silicone containing acrylic monomer, methacryloxyethyl polymethylhydrosiloxane ether (MEPMHSE), based on polymethylhydrosiloxane (PMHS) and 2-hydroxyethyl methacrylate (HEMA) has been synthesized for formulation of nanocomposite emulsion. Then Poly (silicone-co-acrylate)/montmorillonite (PSAM)/nanocomposite emulsion were prepared by in situ intercalative emulsion polymerization of methyl methacrylate (MMA), butyl acrylate (BA), methacrylic acid (MAA) and MEPMHSE, in the presence of organic modified montmorillonite (OMMT) with different OMMT contents (0, 0.5, 1.0, 1.5 and 2 wt%) and auxiliary agents in the presence of potassium persulphate (KPS) as initiator. Alkylphenol ethersulphate and Arkupal N-300 were used as anionic and non-ionic emulsifiers, respectively. The resulting monomer was characterized by Fourier transformer infrared spectroscopy (FTIR), proton (¹H NMR), and carbon (¹³C NMR) nuclear magnetic resonance spectroscopes. The OMMT was characterized by FTIR and X-ray diffraction (XRD). The nanocomposite emulsions were characterized by using Fourier transform infrared spectroscopy (FTIR), laser light scattering and surface tension. Thermal properties of the copolymers were studied by using thermogravimetric analysis (TGA) and dynamic mechanical thermal analysis (DMTA) and then the effects of OMMT percent on the water absorption ratio and drying speed were examined. Results showed that OMMT could improve the properties of emulsion, in other words, the properties of nanocomposite emulsion were better when compared with those of the silicone–acrylate emulsion. The property of nanocomposite emulsion containing 1 wt% OMMT was the best one, and the following advantages were obtained: smaller particle size, faster drying speed, smaller surface tension, and improved resistant water by the incorporation of OMMT.     

中低品位膨润土的有机化及在泥浆中的应用

以新疆乌兰陵格产中低品位钠基膨润土为原料,用十六烷基三甲基铵盐(氯化物D1631和溴化物CTAB)作插层剂,制备有机膨润土。通过实验确定了制备有机膨润土的季铵盐加入量是85～90mmol/100g土。用红外(FTIR)、X-衍射(XRD)和扫描电镜(SEM)表征了有机土结构。FTIR谱显示有机插层剂已进入膨润土的层间,XRD特征峰位移表明膨润土的层间距由1.23nm增加到3.26nm。SEM观察到有机土形貌显著改变,颗粒松散。结果表明膨润土的层间距增大,粒层厚度约为72nm左右。测试了有机膨润土的钻井油基泥浆性能,结果表明,其塑性粘度为7.0mPa·s,表观粘度为8.5mPa·s,动切力为1.5Pa,滤失量40.0mL,均已达到钻井液用有机土的质量指标要求。     

高效脱色絮凝剂脱色絮凝机理浅探及其应用

对高效脱色絮凝应用于染料,印染工业废水脱色絮凝处理的机理进行了探讨,;从物质的结构和基团反应分析类比了脱色剂的化学,物理作用并以实验为佐证。详细介绍了高效脱色絮凝剂在试验室和工业生产中的应用试验结果。高效脱色絮凝剂对公认难以处理的高浓度,高色度染料,染色等工业废水具有脱色和降低ＣＯＤ作用,ＣＯＤ去除率为５０％－９０％,色度去除率为８０％－９９．９％。     

多级孔金属有机骨架材料的合成及其在生物医药中的应用研究进展

金属有机骨架（metal-organic frameworks,MOFs）是多孔材料领域的研究热点之一。MOFs具有高比表面积和孔道均一等特点,但微孔MOFs在大分子应用领域受到限制。本文介绍了延长配体法、模板剂法和聚合物法等多种制备多级孔MOFs的方法,合成后的多级孔MOFs兼具微孔、介孔和大孔,能够参与大分子反应,同时具有水热稳定性和化学稳定性,在催化、气体吸附分离、储能材料等诸多领域表现出优异性能。本文重点介绍了多级孔MOFs在生物医药领域的研究进展,结果表明多级孔MOFs是一种孔道可调节、可在特定条件下分解的生物相容性材料,用于固定化酶和负载医药分子均表现出良好性能。最后讨论了多级孔MOFs材料制备和应用目前存在的问题与挑战,展望了多级孔MOFs材料作为一类新型功能化多孔材料的应用前景。     

Development of dual-model classical density functional theory and its application to gas adsorption in porous materials

Classical density functional theory (CDFT) is a useful theory in many fields. The basis of CDFT is spherical model and extending it to nonspherical molecules is a challenging issue due to the orientation/configuration of the molecules, which implies more complicated molecular models, and higher computational costs. In this work, we propose a dual-model classical density functional theory (DM-CDFT) to address this issue. The theory uses a more precise model (all-atom model) and a simpler model (coarsening model) to construct the external and excess free energy functionals, respectively. By using this methodology, CDFT could handle orientation/configuration effects with low computational costs. The theory is examined by applying it to gas adsorption (such as C₂H₂/C₂H₄/C₂H₆ and toxic gases) in porous materials, and the predicted adsorption isotherms verify the accuracy of the theory. Additionally, the predicted density profile indicates that rotation entropy plays an important role in the adsorption of nonspherical molecules.     

热膨胀系数简易测量装置研制及若干材料测量

以液氮为冷源,研制了一套基于千分测微器的材料热膨胀系数简易测量装置,能够测量80~353 K温区各类固体材料的热膨胀系数,可重复性高于99.3%,不确定度小于3.34%。通过将T1紫铜、6060铝、304不锈钢、尼龙、G10环氧树脂等典型材料热膨胀系数测量数据与文献数据比较,发现两者最大相对偏差小于6.0%,80~353 K温区的平均偏差约为3.1%。在此基础上,测量并获得了高低温热环境工程等应用场合常用到的其他一些材料如殷钢、6262铝、316不锈钢、45钢、聚四氟乙烯、ABS塑料等的热膨胀系数数据。     

桐油及其衍生物的改性在高分子材料中的应用进展

综述了4种桐油改性方法并且介绍了桐油及其改性衍生物在高分子材料应用中的主要进展.讨论了桐油的Diels-Alder反应、Friedel-Crafts反应、氧化聚合和烯烃自由基聚合改性反应及聚合机理,在此基础上,对桐油的改性方法及其在高分子材料中的应用前景进行了展望.     

Water-retention properties of porous ceramics prepared from mixtures of allophane and vermiculite for materials to counteract heat island effects

Porous ceramics for anti-heat island effect were prepared from mixtures of allophane and vermiculite (VA samples). Allophane and vermiculite which had been ground for 0.5–2 h was mixed in various mass ratios, formed into pellets by uniaxial pressing at 40 MPa, and heated at 600–800 °C to form porous ceramics. The large thermal expansion of the vermiculite upon explosive dehydration of interlayer water causes cracking of the pellets with higher vermiculite contents. However, this can be controlled by grinding the vermiculite prior to heating. Grinding the vermiculite for ≥2 h suppresses its expansion, enabling pellet samples with high vermiculite contents to be prepared without cracking. The bulk densities of samples prepared at 800 °C from vermiculite ground for 2 h decrease from 1.72 to 0.94 with increasing allophane content. The pore size distribution in these samples shows a distinct peak at about 1 μm irrespective of the mixing ratio. The number of smaller pores (<50 nm) increases with increasing allophane content while the number of larger pores (20–40 μm) increases with increasing vermiculite content. The compressive strengths of the samples range from 1 to 3 MPa except for samples containing a high proportion of vermiculite ground for 1 h. The water absorption (W_a) of the samples increases from 37 to 63% with increasing allophane content. This absorption rate is fast enough to absorb >90% of the W_a within 1 min for samples of 10 mm Ø × 5 mm³ size. By contrast, the release of the absorbed water is very slow, with 50% of the W_a retained for ≥30 h in the VA samples at a relative humidity of 55% at 20 °C; this is slower than in pure allophane and much slower than in a reference sample of foamed glass (about 4 h). All these properties make the VA samples useful as water-retaining materials to combat “heat island” effects.     

The origin of the pozzolanic activity of calcined clay minerals: A comparison between kaolinite, illite and montmorillonite

This paper investigates the decomposition of three clayey structures (kaolinite, illite and montmorillonite) when thermally treated at 600 °C and 800 °C and the effect of this treatment on their pozzolanic activity in cementitious materials. Raw and calcined clay minerals were characterized by the XRF, XRD, ²⁷Al NMR, DTG and BET techniques. Cement pastes and mortars were produced with a 30% substitution by calcined clay minerals. The pozzolanic activity and the degree of hydration of the clinker component were monitored on pastes using DTG and BSE-IA, respectively. Compressive strength and sorptivity properties were assessed on standard mortars. It was shown that kaolinite, due to the amount and location of OH groups in its structure, has a different decomposition process than illite or montmorillonite, which results in an important loss of crystallinity. This explains its enhanced pozzolanic activity compared to other calcined clay–cement blends.     

多孔材料在催化CO2与环氧化物环加成反应中的研究进展

以CO2为原料与环氧化物合成环状碳酸酯是实现CO2资源利用最为有效的途径之一，也是缓解温室效应的有效方式之一。在该反应中催化剂的选择至关重要，多孔材料由于具有相对密度低、强度高、比表面积大、稳定性好、合成方法多样等优点而被广泛应用于催化CO2环加成。重点综述了近年来无机多孔材料、多孔有机聚合物材料、金属有机骨架材料在催化CO2与环氧化物合成环状碳酸酯中的研究进展，介绍了各催化剂的优缺点并对未来多孔材料的发展进行了展望。     

Surface modification of montmorillonite and application to the preparation of polybutadiene/montmorillonite nanocomposites

Hydrophobic organic montmorillonite (OMMT) which exists as stable dispersions in cyclohexane has been prepared by the combined modification of quaternary ammonium salts and coupling agents, and polybutadiene (PB)/OMMT nanocomposites (NCs) were successfully synthesized by in situ living anionic polymerization. The results showed that the interlayer spacing of OMMT increased dramatically on increasing the length of the long alkyl chain of C12, C16, C18 and C22 in n‐alkyltrimethylammonium ions and the number of long alkyl chains of 1C16, 2C16 and 3C16 in hexadecylmethylammonium ions. The interlayer spacings reached 4.9 and 5.07 nm, respectively, when C22 and 3C16 were used. The dispersion of MMT intercalated by quaternary ammonium salts was improved significantly after surface modification by different coupling agents, and the OMMTs could be disperses stably in cyclohexane for at least 72 h. In addition, the coupling agents did not change the inherent intercalation structure of OMMT. The results from a kinetic study and ¹H NMR analysis indicated that the incorporation of OMMT had little influence on the living polymerization and PB microstructure (proportions of 1,2‐ and 1,4‐units) when the OMMT content was below 3 wt%. However, the OMMT modified by different coupling agents had some influence on the molecular weight distribution. The results from transmission electron microscopy and X‐ray diffraction revealed that exfoliated structures of clay were obtained for all NCs. Furthermore, the results of differential scanning calorimetry and thermogravimetric analysis indicated that T_g and T_dc of NCs were increased compared to those of PB. Copyright © 2006 Society of Chemical Industry     

Synthesis of nanoporous carbons from mixtures of coal tar pitch and furfural and their application as electrode materials

Synthetic nanoporous carbons are prepared by polymerization of mixtures containing coal tar pitch and furfural in different proportions, followed by carbonization of obtained solid product and steam activation of the carbonizate. The chemical composition of the initial mixture significantly affects the physicochemical properties (surface area, pore structure, electro resistance and amount of oxygen-containing groups on the surface) of the obtained materials. The incorporation of oxygen in the precursor mixture by means of furfural, has a strong influence in the synthetic step; increasing the furfural content facilitates the formation of a solid product characterized by a large oxygen content. Moreover, the solid product is more reactive towards activation as the furfural content increases, giving rise to nanoporous carbons with large surface areas and unique chemical features (high density of oxygen functionalities of basic nature). These nanoporous carbons have been investigated as electrodes in electrochemical applications.     

Fabrication and application of porous materials made from coal gangue: A review

Coal gangue (CG), which is mainly generated during coal excavation, mining, and coal washing, is an industrial solid waste that is recognized as an environmental pollutant. The ever-increasing amount of CG produced is a serious threat to the ecological environment and property safety, especially in China, which is the largest coal producer and consumer in the world. Considerable studies have investigated means for utilizing CG worldwide. This review summarizes and discusses various porous inorganic materials made from CG, including cement-based porous materials, porous bricks, porous ceramics (cordierite and mullite) and glasses, porous geopolymers, zeolites, aerogels, and porous carbon materials. Different preparation processes and performances of each type of porous inorganic materials were reviewed. Porous CG-based materials can be used as promising adsorbents for the removal of various pollutants and have good potential for use in construction industry as well as catalyst material applications. Besides, porous materials obtained from CG have also been tested as slow-release fertilizers after the absorption of phosphate, as electrode materials, and as oil-in-water separation agents. The systematic summary of porous materials based on CG aims at promoting high-value-added applications for this waste. Future research directions for the use of CG as a raw material are also presented.     

铁基柱撑蒙脱石的制备及其应用于芘吸附的研究

以钙基蒙脱石（Ca-MMT）、硫酸亚铁作原料，通过柱撑、煅烧方式制备铁基柱撑纳米蒙脱石(Fe-MMT)，利用SEM、TEM、XRD、TGA等手段对样品结构进行表征，考察了Fe-MMT、Ca-MMT吸附性能的变化，探究了其对吸附多环芳烃的机理。结果表明：相对于Ca-MMT，Fe-MMT结晶度降低，但热稳定性增强。表面形貌发生变化，铁元素取代部分钙元素，铁元素含量达到5.597%，铁元素吸附率达到99.95%。 Ca-MMT总比表面积为29.86 m2/g，而Fe-MMT比表面积上升至51.29 m2/g。相应地，Ca-MMT吸附芘的容量约为15.00 mg/g，而Fe-MMT吸附芘分子的容量升高至95.43 mg/g，吸附芘的容量明显增加。5次循环利用后其Fe-MMT吸附容量仍然能达到0.709 mg/g， 维持在初始吸附量的88%以上，具有可循环利用性。由此推断出：应用此方法制备的Fe-MMT具有应用于疏水性有机污染物去除的潜力。