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一种新型复合材料对氟离子吸附性能的影响 总被引:3,自引:0,他引:3
将钛酸丁酯加到多孔球状吸附树脂中,用一水溶液将该醇盐水解,制得由钛的水合氧化物和多孔树脂组成的复合材料,本文研究了这种复合材料对氟离子的吸附性能。 相似文献
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吸附树脂的制备及吸附蛋白质的研究 总被引:1,自引:0,他引:1
本文用醇钠活化球状聚乙烯醇颗粒,Williamson醚化法制得了大孔径的吸附树脂。以牛血清白蛋白(BSA)为模型蛋白,研究了蛋白质在多孔吸附树脂表面的吸附行为。通过测定蛋白质的吸附等温线,并用线性最小二乘法对曲线进行拟合,发现蛋白质在疏水吸附树脂的吸附等温线可用Langmuir方程描述。 相似文献
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一、基本原理分离提纯用的树脂有吸附树脂和离子交换树脂。吸附树脂一般是按照制备大孔型离子交换树脂骨架的方法制得的。这些树脂是未经功能基反应,不带离子交换功能基的多孔树脂骨架,也叫多孔小白球。有些是由带极性基团的单体制成的,也就是离子交换树脂,两者很难严格区分。带离子交换功能基的交联聚合物小球粒就是离 相似文献
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<正> 钪(Sc)是一种稀土元素,近年来在电子工业中的用量越来越大。稀土元素的分离提浓目前大多采用溶剂萃取法,效率很难提高。日本东北工业技术试验所开发成功了采用浸渍酸性膦酸酯的多孔树脂从强酸性溶液中分离提浓钪的方法,提浓效率高,树脂对钪的吸附量为10g/kg树脂。该多孔树脂选择性地与钪形成配位化合物,被吸附在树脂 相似文献
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王金泉 《精细与专用化学品》1988,(12)
D312吸附树脂是由华北制药厂提供技术、山东张店化工厂与华北制药厂共同开发的产品。大孔吸附树脂为多孔的无交换功能基团的树脂骨架结构,它是六十年代发展起来的新型吸附剂,其在医药卫生、石油化学 相似文献
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根据多孔树脂结构的设计,利用二次致孔法制备了CMC-g-PAM/PAAS多孔树脂。通过TG、SEM、FTIR、XRD和氮气吸附法等手段表征了该树脂的形貌和结构特征,测试了多孔树脂分别在高湿和低湿条件下的调湿平衡和最大湿含量,分别讨论了绝对湿度变化条件和温度变化条件下多孔树脂的调湿性能。结果表明,AlCl3的质量分数为丙烯酰胺单体的2.5%时,多孔树脂的调湿平衡范围为57.5%~62.5%,最大湿含量为自身质量的122%。在绝对湿度变化条件下,多孔树脂仍能维持相对湿度在57.5%~62.5%范围之内;在温度变化条件下,多孔树脂在40℃时的调湿平衡时间不超过1h,在10℃时的调湿平衡时间不超过3h。 相似文献
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单宁与多聚甲醛交联合成单宁酚醛聚合物,再以环氧氯丙烷为交联剂,将单宁酚醛聚合物与纤维素通过反相悬浮交联制备球形聚合单宁-纤维素树脂。通过傅里叶变换红外光谱(FTIR)、扫描电子显微镜(SEM)对球形聚合单宁-纤维素树脂的结构进行了表征,并考察了球形聚合单宁-纤维素树脂对盐酸小檗碱的吸附性能。结果表明,球形聚合单宁-纤维素树脂具有多孔的结构,树脂网络中含有大量的酚羟基;球形聚合单宁-纤维素树脂对盐酸小檗碱具有较好的吸附性能,当盐酸小檗碱浓度为600 mg·L-1、吸附温度为298 K时,最大饱和吸附量可达245.92mg·g-1;球形聚合单宁-纤维素树脂对盐酸小檗碱的吸附过程符合Langmuir吸附等温模型和准二级吸附动力学方程,热力学研究数据表明球形单宁-纤维素树脂对盐酸小檗碱的吸附是一个自发放热的物理吸附过程。该树脂在分离提纯生物碱方面具有潜在的应用前景。 相似文献
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直接空气捕碳(DAC)技术属于一种负碳技术,作为碳捕集、存储和利用(CCUS)技术的有效补充,是助力实现“双碳”目标的重要技术之一。由于吸附能力强、再生能耗低、应用场景灵活以及结构可调性强,固体多孔材料在降低DAC经济成本和运行能耗方面具有不可替代的优势。本文从固体多孔材料的DAC原理出发,重点综述了包括沸石吸附剂、硅基吸附剂、炭基吸附剂、纳米氧化铝吸附剂、金属有机框架(MOF)材料吸附剂和多孔树脂材料吸附剂等DAC的研究现状,系统介绍和比较了固体多孔吸附材料的吸附容量、吸附选择性、水热稳定性、再生能耗以及循环稳定性方面的优缺点。本文着重分析了胺功能化改性和载体孔隙结构等因素对吸附CO2性能的影响规律,对各类固体多孔材料在DAC应用中面临的挑战提出了具体的优化方向,并指出未来固体多孔吸附材料的设计开发应兼顾经济性和高效性,加快开展中试规模的DAC试验研究。 相似文献
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Porous polyethylene with nanofiber structure in the form of discrete, freeflowing, micron-sized spheres was formed in high activity by ethylene polymerization with porous polymer supported Ziegler-Natta catalyst. Such versatile porous support catalyst played as a template in two levels. One level is the whole support beads, which resulted in the porous polyethylene spheres. Another level is the porous structure in the support beads, which played as a nanoreactor and resulted in the nanofiber structure in the polyethylene spheres. 相似文献
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A novel approach to monodispersed porous polymer beads allowing accurate control over a broad range of pore size distribution has been developed. It involves the use of monodispersed template particles which are used as polymeric porogens in the suspension polymerization of monomers such as styrene and divinylbenzene. The size uniformity of the template particles is retained by the final porous beads. The porous properties of the final beads are determined in large part by the characteristics of the porogenic mixture such as its composition, the molecular weight of the polymeric porogen, as well as the relative amount of monomers, polymeric and low molecular weight porogens used. 相似文献
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以浓乳液作为悬浮聚合的油相,采用水(W)/油(O)/W浓乳液/悬浮聚合方法制备出了内部具有通孔结构、粒径均一的聚甲基丙烯酸叔丁酯多孔微球。结果表明,通过研究乳化剂含量、搅拌速度等参数对多孔微球的内部微孔形貌与微球粒径的影响,发现当乳化剂含量为4 %时,得到的聚合物微球内的微孔结构分布均匀;而聚合物微球的平均粒径会随着搅拌速度的增大而减小。将不同粒径的多孔微球进行酸化水解后得到了表面羧基官能化的聚合物多孔微球,利用其丰富的通孔结构实现了对铜离子(Cu2+)的有效吸附,当微球平均粒径介于200~300 μm时,铜离子的去除率最高,可达99.3 %。 相似文献
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Compounds having acid anhydride moiety have been used for starting materials for many useful derivatives. Spherical crosslinked polymer beads of porous maleic anhydride–styrene–divinylbenzene copolymer are obtained by suspension polymerization. Glycerol is found to be a preferable dispersant to make spherical beads. The beads contained 93% of the anhydride and 7% of the free carboxyls. As one of applications, the beads were hydrolyzed or reacted with anhydrous hydrazine, and the metal sorption behavior of them was examined. The hydrolyzed beads show a similar sorption manner as a conventional cation exchange resin having carboxylic acid groups, but the hydrazide beads sorbed mercury (II) selectively over a wide pH range. This investigation suggests a simple preparative method for the insoluble spherical porous beads of the maleic anhydride copolymer. 相似文献
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ABSTRACT: We successfully synthesized two different structures, silica nanospheres and porous polymer membranes, via nanophase separation between silica sol and polymer. Silica sol, which was in-situ polymerized from tetraorthosilicate, was used as a precursor. Subsequently, it was mixed with a polymer that was used as a matrix component. It was observed that nanophase separation occurred after the mixing of polymer with silica sol and subsequent evaporation of solvents, resulting in organizing various structures, from random network silica structures to silica spheres. In particular, silica nanospheres were produced by manipulating the mixing ratio of polymer to silica sol. The size of silica beads was gradually changed from micro- to nanoscale, depending on the polymer content. At the same time, porous polymer membranes were generated by removing the silica component with hydrofluoric acid. Furthermore, porous carbon membranes were produced by using carbon source polymer through the carbonization process. 相似文献
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Macroporous chitosan beads used for the immobilization of an anti-inflammatory drug were prepared by the wet phase-inversion method. There are two stages of phase-inversion observed from the cast of chitosan droplet in tripolyphosphate (TPP) aqueous solution. The first stage of phase-inversion is dominated by liquid-liquid demixing and the morphology of the freeze-dried chitosan bead shows a bundle-like porous structure. The following stage of phase-inversion is attributed to the solid-liquid demixing and the morphology of the freeze-dried chitosan bead changes to an interconnected porous structure comprising particulates around the pores. The pore size and porosity of the bead can be varied by altering synthesis conditions, such as initial polymer concentration, and the pH value and concentration of the casting agent (TPP aqueous solution). Quaternary ammonium, and aliphatic and aromatic acyl groups were introduced into the porous chitosan beads to interact with an anti-inflammatory drug, indomethacin, through the electrostatic interaction and hydrophobic interaction. The results indicated that chemical modification of the porous chitosan beads have obvious effect on the adsorption of indomethacin. 相似文献
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Summary Anionic exchange resins with a gradient in polymer composition were prepared in two stages. After P(S-co-DVB) suspension beads
were obtained, N,N-diethylaminoethyl methacrylate monomer was let to diffuse into the beads at 25 °C, and immediately photopolymerized
to fix the gradient polymer composition with high surface concentration of ion exchanger. Chemical composition through the
radial position was estimated by means of a mathematical algorithm and using UV spectroscopy. Resin characterization included
particle size distribution, “settled” density and total anion exchange capacity, following ASTM D-2187. Values were compared
with a porous commercial resin (Amberlite IRA900RF Cl). Since non porous structure with high ion exchange capacity resins
were obtained, useful resins for ion exchange with long term stability can be prepared with this methodology. 相似文献
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The aim of this work was preparation of the macroporous titania coatings with the use of the sol–gel process and poly(methylmetacrylate) beads as a template. The effectiveness of the Langmuir–Blodgett (LB) and dip-coating (DC) methods in deposition of polymer beads on the silicon wafers was compared. Resulted polymer layers and final porous titania coatings were analyzed with the use of the atomic force microscope. It was found, that application of the LB is possible only when arachidic acid is present in the subphase. It should be highlighted, that the application of the LB method is the novelty between the methods of the polymer beads arrangement having the diameter of 200–300 nm. Main factors which influence the structure and the arrangement of polymer templates were the concentration of the polymer suspension and the rate of the substrate immersion/withdrawal from the suspension. We established, that the optimal concentrations for preparation of polymer templates, exhibiting good arrangement of individual beads, were 0.5 and 6 % for LB and DC methods, respectively. The size of pores of the obtained macroporous titania (200–330 nm) corresponds well with the size of the polymer beads used as the template (200–235 nm). 相似文献
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Takashi Iizawa Hatsumi Taketa Makoto Maruta Takashi Ishido Takehiko Gotoh Shuji Sakohara 《应用聚合物科学杂志》2007,104(2):842-850
Sedimentation polymerization of aqueous solutions of N‐isopropylacrylamide (NIPA) was carried out to prepare porous poly(N‐isopropylacrylamide) (PNIPA) beads. When small amounts of DMF and a radical accelerator were added to the monomer solution, the polymerization proceeded smoothly to give polymer beads with a very narrow size distribution. The rate of swelling of the resulting bead increased with increasing crosslinker content and was also affected by the type of crosslinker used. When amounts higher than 1 mol % N,N′‐methylenebisacrylamide or 3 mol % diethylene glycol diacrylate (DEGDA) were used as a crosslinker, the resulting beads underwent rapid swelling in water at 20°C, reaching the equilibrium within 5 min. A cross‐sectional photograph of a typical dried bead showed that it had a very complex morphology consisting of a large and irregular void, highly porous region, and nonporous region. The swelling rate was directly dependent on the morphology of the beads. PNIPA beads with well‐developed porous areas show a high swelling rate. Although PNIPA beads produced from DEGDA had well‐developed porous structures, they were able to effectively concentrate blue dextran from the dilute aqueous solution. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci 104: 842–850, 2007 相似文献
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The morphology of the beads of polymer produced by polymerization of ethylene with an aluminasupported zirconium tetrabenzyl catalyst has been studied as a function of conversion. Before polymerization starts the alumina is in the form of spherical particles of diameter 20–70 μm made up of porous aggregates of subparticles of diameter 0.1–0.6 μm. Polymerization causes these particles to expand to form hollow, spherical beads of polymer whose inner walls contain clusters of alumina subparticles whose occurrence decreases with conversion. As the conversion increases there is considerable fissuring of the beads and at high conversions the walls are made up of ‘worms’ of polymer connecting clusters of catalyst subparticles; these worms have diameters of around 0.6 μm and are very similar to those observed from a wide variety of related catalyst systems. Differential scanning calorimetry analysis and optical microscopy of the polymer beads show a high melting temperature, a rapid increase in melting temperature with heating rate, delayed loss of birefringence in the melt and a rapid reversion to normal behaviour on nitric acid treatment, suggesting that the polymer is formed in a highly drawn state. It is proposed that the observed morphology arises from the interaction of monomer diffusion rate and polymerization rate. Using estimates for the diffusion rate of ethylene under various conditions it is shown that the observed morphology is consistent with a process which becomes diffusion controlled quite early in the reaction so that hollow beads are formed. With increasing conversion, expansion of the outer layers of the bead causes drawing and the production of worms. At the same time fissuring of the surface allows the ingress of monomer into the interior of the beads whose walls grow relatively uniformly at higher conversions. 相似文献