一步聚合法合成多孔磁性高分子微球及其机理研究

在羰基铁粉存在下,将苯乙烯与甲基丙烯酸甲酯通过悬浮聚合方法制备了表面多孔的磁性高分子微球。采用SEM、FTIR及XRD等对样品进行了表征。研究表明,聚合形成的磁性高分子微球表面粘附着40 nm左右的聚合物粒子,这些粒子之间形成孔隙。具有两亲性和可接枝聚合的明胶分子促成了单体在羰基铁粉表面引发并聚合。     

BaFe12O19/聚氨酯磁性复合微球的制备和表征

通过BaFe12O19硅烷偶联剂改性,聚乙二醇1000、甲苯二异氰酸酯在二甲苯溶液中预聚合,预聚物溶液在分散剂聚乙烯吡咯烷酮K30的水溶液中悬浮聚合,三步合成了BaFe12O19/聚氨酯复合微球.用扫描电镜、红外光谱仪、热重-差示扫描同步热分析仪和振动样品磁强计对微球的形貌、结构、玻璃化温度(Tg)和磁性能进行了表征.结果表明:合成的微球以BaFe12O19颗粒为核聚氨酯为壳.表面分布有微孔,微球粒径在400μm左右,粒径大小可通过控制反应条件调节.微球中磁性物质BaFe12O19的含量为11.11%(质量分数),Tg在290 ℃左右,耐热性能好,微球的饱和磁化强度为3.36×103 A/m,矫顽力为3.06×104 A/m.该复合微球是一种有潜在应用价值的新型血管内栓塞材料.     

磁性琼脂糖复合微球的制备和性质

采用乳化复合技术制备出粒径为２０～３００ｎｍ、分散系数为０．０９０～０．６０１、Ｆｅ３Ｏ４含量（ｗ）为７．５％～６１．３％的具有磁核的琼脂糖复合微球。该微球呈珠形,在４～９０℃的水介质中形成均匀稳定的分散液,在０．０５Ｗｂ／ｍ２的弱磁场中具强磁响应性。制备微球的最佳条件是：琼脂糖用量１２．５～８７．５ｍｇ／ｍｌ,氯化亚铁用量１５～１２０ｍｇ／ｍｌ,ｐＨ＞１０。     

分散聚合法制备环氧基磁性复合微球

采用化学共沉淀法制备了油酸包覆的Fe3O4磁性纳米粒子,以此为核·采用分散聚合法制备了表面带有环氧基团的Fe3O4／聚甲基丙烯酸缩水甘油酯（PGMA）磁性复合微球,探讨了聚合工艺、聚合条件对甲基丙烯酸缩水甘油酯（GMA）利用效率的影响规律,并用傅立叶变换红外光谱仪（FTIR）、热重分析仪（TGA）、振动样品磁强计（VSM）和扫描电镜（SEM）等对磁性复合微球的结构、磁性能和包覆量进行了表征．采用盐酸一丙酮法测定了磁性复合微球表面环氧基的含量。结果表明,在优化的条件下。GMA利用效率高达61．26％。磁性复合微球具有良好的单分散性·粒径为1～2μm．具有超顺磁性．比饱和磁强度为17．12emu·g^-1。环氧基含量达3．5mmol·g^-1。     

带环氧基的超顺磁性高分子微球的制备及其性能表征

Micron-size superparamagnetic poly(styrene-divinylbenzene-glycidyl methacrylate) (PSt-DVB-GMA)spheres were prepared via a modified suspension copolymerization method. Oleic acid coated magnetite (Fe3O4) nanoparticles made by co-precipitation were first mixed with monomers of St, DVB, GMA, and benzoyl peroxide (BPO) to form oil in water suspension with the presence of poly(vinyl pyrrolidone) (PVP-K30) as a stabilizer.Then the temperature of mixture was increased at a controlled rate to obtain small and relatively uniform droplets.Finally, the copolymerization reaction was initiated by the decomposition of BPO. The morphology and properties of magnetic PSt-DVB-GMA microspheres were examined by SEM, TEM, VSM, XRD and FT-IR. The magnetic microspheres obtained have very small size (about 4-7 μm) in diameter with narrow size distribution and superparamagnetic characteristics. Powder X-ray diffraction measurements show the inverse cubic spinel structure for the magnetite dispersed in polymer microspheres. FT-IR spectroscopy indicates extensive oxirane groups existed on the surface of magnetic PSt-DVB-GMA microspheres.     

磁性多孔聚苯乙烯微球的制备

在磁流体存在的情况下,采用改进了的乳液聚合法合成了具有磁核的微米级高分子聚苯乙烯微球。以该微球为种子,采用分散聚合法,以乙二醇／水为分散介质、聚乙二醇为分散剂、甲苯为制孔剂,进行苯乙烯-丙烯酸-二乙烯苯的三元共聚物的合成,最终合成出粒径分布均匀、磁响应性强的磁性多孔聚苯乙烯微球。     

羧基磁性高分子微球的制备和表征

用改进的悬浮聚合法制备了表面含有羧基功能团的聚苯乙烯磁性微球。考察了磁微球的形态与结构 ,测定了磁微球的粒径与磁响应性 ,主要研究了单体 /水、丙烯酸 /单体、反应温度和反应时间对磁性微球形成的影响 ,并对磁性微球的生物吸附活性进行了表征。优化得到了制备具有良好生物吸附活性的羧基磁性微球的最佳实验条件     

细乳液聚合制备磁性复合微球研究进展

介绍了细乳液聚合的特点、细乳液聚合制备磁性复合微球的一般步骤;从制备影响因素角度,对近年来国内外细乳液聚合制备磁性复合微球的研究进行了综述。磁性复合微球主要采用正相细乳液聚合,影响微球制备的主要因素有乳化剂类型和用量、磁性纳米粒子表面修饰、超声分散、助稳定剂类型、交联剂引发剂和磁流体用量等。今后,细乳液聚合制备磁性复合微球的研究仍将关注提高复合微球性能(高磁响应性能、粒子大小可控且均匀、具有表面功能基团)及产率(磁性粒子包覆率)等方面。     

多孔Fe_3O_4/C磁性复合微球的制备及其对RhB的吸附性能

以油酸同步修饰共沉淀法制备的Fe3O4为铁磁性原料,通过悬浮聚合的方法制备Fe3O4/PDVB磁性复合微球,氮气氛围下烧结最终得到了具有多孔结构的Fe3O4/C磁性复合微球。采用SEM、TGA、VSM及压汞仪等手段对复合微球的形貌、磁性能和孔性能等进行了表征。结果表明,微球平均粒径约为120μm,磁含量和最大比饱和磁化强度分别为49.29%和39.31 emu/g,平均孔径和累积比表面积分别为382.5 nm和21.41 m2/g。将制得的多孔Fe3O4/C磁性复合微球用于罗丹明B(RhB)的吸附研究,微球表现出了良好的吸附效果和重复使用性。     

磁性淀粉微球药物载体的合成及表征

先合成表面接羟基的磁流体,再在表面包覆上一层可溶性淀粉,采用悬浮聚合法和分散聚合法交联聚合成球,制得表面带羟基的磁性复合微球。经红外光谱、扫描电镜及粒度分析。结果表明,悬浮聚合法合成效果好,磁性淀粉复合微球分散性好,粒径在16~120μm占77%,Fe3O4在微球中平均含量为2.55 mg/g,微球结构坚韧,抗水溶性好。     

分散聚合法合成含有环氧基的无孔超顺磁性微球及其表征

Non-porous superparamagnetic polymer microspheres with epoxy groups were prepared by dispersion polymerization of glycidyl methacrylate (GMA) in the presence of magnetic iron oxide (Fe3O4) nanoparticles coated with oleic acid. The polymerization was carried out in the ethanol/water medium using polyvinylpyrrolidone (PVP) and 2,2'-azobisisobutyronitrile (AIBN) as stabilizer and initiator, respectively. The magnetic microspheres obtained were characterized with scanning electron microscopy (SEM), vibrating sample magnetometry (VSM) and Fourier transform infrared spectroscopy (FTIR). The results showed that the magnetic microspheres had an average size of 1μm with superparamagnetic characteristics. The saturation magnetization was found to be 4.5emu·g-1. There was abundance of epoxy groups with density of 0.028 mmol·g-1 in microspheres. The magnetic PGMA microspheres have extensive potential uses in magnetic bioseparation and biotechnology.     

聚苯乙烯多孔吸附微球的制备

通过悬浮聚合和超交联两步法合成了具有介孔结构的改性聚苯乙烯微球用作血液净化材料。首先采用悬浮聚合法制备了亲水改性的苯乙烯马来酸酐共聚微球（MPPS）,然后将MPPS微球以二氯甲烷为溶剂、无水氯化铝为催化剂进行后交联处理,制备了含有介孔结构的、具有较高比表面积的聚苯乙烯(HCLPS)多孔微球。采用比表面积测试、扫描电子显微镜、傅里叶红外光谱、X射线光电子能谱等仪器分析表征了微球的结构和形貌,并测试了HCLPS微球的吸水性和戊巴比妥钠吸附性能。结果表明,超交联反应可以显著提高微球的比表面积,并且随着马来酸酐(MAH)含量增加,微球的吸水性和戊巴比妥钠吸附性能提高;当MAH含量为20 %（质量分数,下同）时HCLPS微球的戊巴比妥钠吸附率为91.90 %。     

表面含羧基的磁性高分子微球的制备和表征

以共沉淀法制备的Fe3O4为磁性来源,选用丙烯酰胺、N,N′-亚甲基双(丙烯酰胺)和丙烯酸分别作为聚合单体、交联剂和功能基单体,通过反相乳液聚合,包裹制备携带羧基的磁性高分子微球。考察了Fe3O4投入量、功能基单体量、交联剂量、聚合时间和介质的变化对磁性高分子微球的形态、磁性质及表面羧基含量的影响。采用SEMI、R、721E分光光度计和化学滴定法进行表征,制备出粒径在500 nm~10μm,表面羧基携带量为1.0 mmol/g的磁性高分子微球。     

Preparation of Magnetic Porous Microspheres and Their Ability to Remove Oils

Magnetic, porous poly (tripropylene glycol diacrylate) (PTPGDA) microspheres are successfully prepared using a combination of microfluidic emulsification and free‐radical polymerization. The porous structure can be precisely controlled by controlling the amount of the oil‐phase emulsifier polyglycerol polyricinoleate (PGPR). The effects of PGPR content and pH on the contact angle of the microspheres is investigated. The contact angle of the microspheres increases with the raise of PGPR content, and the hydrophobicity of the microspheres remains stable at different pHs. The microstructure, magnetic properties, and oil adsorption abilities of the microspheres are also studied. The as‐prepared microspheres perform adsorption well, the higher the PGPR content, the more pore structures and larger contact angle occurres on the microspheres, which improves the adsorption capacity. In addition, the adsorption capacity of the microspheres for diesel can reach 3.38 g·g^?1 when the mass fraction of PGPR in oil phase is 50% w/v. After adsorbing oil, the microspheres can be separated, recovered, and reused by applying an external magnetic field. The magnetic microspheres have good oil adsorption abilities and recyclability, which shows their potential for use in oil removal.     

Regeneration Research of Porous Magnetic Microspheres during Treatment of Wastewater Containing Cationic Dyes

The application feasibility of porous magnetic microspheres in the removal of cationic dyes from wastewater was investigated. Various desorption solutions were employed for the recovery of cationic dyes from absorbents and regeneration of porous magnetic microspheres. The results showed that 1 M NaCl or 1 M KCl in water/methanol co-solvent had excellent desorption ability for methyl violet. This fact was further demonstrated in the removal cationic gold yellow from its aqueous solution. Overall, this provided a simple methodology for the treatment of wastewater containing cationic dyes and the regeneration of porous magnetic microspheres.     

P(St-GMA-DVB)/Fe3O4高分子磁性微球的合成与表征

以FeCl3×6H2O和FeCl2×4H2O为原料,采用化学共沉淀法制备了Fe3O4油基磁流体,设计的合成工艺克服了合成磁流体过程中Fe3O4磁性粒子易团聚的缺点,合成了具有很好分散性和稳定性的磁流体,比饱和磁化强度达72.60 emu/g. 采用悬浮聚合方法合成了聚苯乙烯-甲基丙烯酸缩水甘油酯-二乙烯基苯[P(St-GMA-DVB)]高分子磁性微球,搅拌转速对磁性微球粒径影响大,磁性微球粒径在55~300 mm范围内,外形为具有单分散性的球形,表面环氧基团含量达17 mmol/g.     

磁性多孔Fe(OH)3微球制备及其在含磷废水处理中的应用

利用诱导成球法制备磁性Fe3O4粒子为核的Fe(OH)3多孔微球,以X射线衍射(XRD)和扫描电镜(SEM)等对其进行结构表征,采用静态吸附法对磁性多孔微球去除水中H2PO4-的性能进行了实验研究,考察了吸附剂用量、H2PO4-初始浓度、溶液pH值等因素对吸附的影响,分析了其吸附等温线及对H2PO4-的吸附动力学. 结果表明,Langmuir方程能较好地描述吸附平衡,其吸附动力学符合Lagergren二级方程. 磁性多孔微球对H2PO4-有很强的去除能力,在吸附剂用量0.8 g/L,pH 2.5~9,吸附时间150 min的条件下,磁性多孔微球对H2PO4-的去除率可达98%以上.