Synthesis of novel magnetic polymer microspheres with amphiphilic structure

Novel magnetic polymer microspheres with amphiphilic structure ranging in diameter from 5 to 80 μm were prepared by dispersion copolymerization of styrene and poly(ethylene oxide) acrylamide macromonomer (MPEO) in the presence of Fe₃O₄ magnetic fluid. The effects of various polymerization parameters on the average particle size were systematically investigated. The average particle size was found to increase with increasing initiator concentration. It also increased with decreasing stabilizer concentration and MPEO concentration. The content of the amino groups localized in the microspheres ranged from 0.01 to 0.25 mmol/g. © 2003 Wiley Periodicals, Inc. J Appl Polym Sci 90: 1879–1884, 2003     

Synthesis of amphiphilic magnetic microspheres by dispersion copolymerization of styrene and poly(ethylene oxide) macromonomer

Amphiphilic magnetic microspheres ranging in diameter from 5 to 100 µm were prepared by dispersion copolymerization of styrene and poly(ethylene oxide) vinylbenzyl (PEO‐VB) macromonomer (MPEO) in the presence of Fe₃O₄ magnetic fluid. The effects of various polymerization parameters on the average particle size were systematically investigated. The average particle size was found to increase with increasing styrene concentration and initiator concentration. It also increased with decreasing stabilizer concentration and molecular weight of MPEO. The content of the hydroxyl groups localized in the microspheres ranged from 0.01 to 0.2 mmol g^?1. © 2003 Society of Chemical Industry     

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。     

Preparation and characterization of fluorescent polymer magnetic particles

Magnetic iron oxide (maghemite, Fe₃O₄) particles were encapsulated with fluorescent polymer phase. The resulting fluorescent magnetic polymer particles were characterized by Fourier transform infrared spectroscopy (FTIR), thermal gravimeter analysis (TGA), reflection optical microscopy, differential scanning calorimeter (DSC), Fritsch particle sizer, scanning electron microscopy (SEM), powder X‐ray diffractometer (XRD), and vibrating sample magnetometer (VSM) measurements. FTIR and XRD confirmed the presence of iron oxide in polymer phase. The TGA and DSC measurements indicated that the magnetic polymer particles have more than 50% iron oxide content and high thermal stability. SEM and reflection optical microscopy under UV light revealed that all maghemite particles were embedded in the polymer spheres and have fluorescent characteristics. The size‐distribution analysis of prepared magnetic particles was shown that the means diameter of the particles slightly increased. According to our magnetometry data, shape of the loops evidences the ferromagnetic character of the material and no evidence of superparamagnetism was seen. © 2008 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

生物提取用磁性微球的制备及其性能

磁性微球因其自身兼具高分子微球和磁性粒子的众多特性,广泛应用在细胞分离、固定化酶、靶向药物、分析检测、免疫测定等领域。本文通过化学共沉淀法制备了Fe3O4纳米粒子,并采用分散聚合法对其包覆,得到Fe3O4/SiO2磁性微球。研究结果表明,通过上述方法制备的磁性微球可以快速、有效的提取生物中的RNA,而且最佳的聚合反应温度为80℃。     

亲水性高分子磁性微球的合成和应用研究

对近年来国内外有关亲水性高分子磁性微球的研究成果和发展现状进行了综述,具体讨论了包埋法、单体聚合法及原位法等常用的合成制备方法及其优缺点,指出反相(微)乳液聚合是制备亲水性聚合物微球的有效方法。分析了亲水性高分子磁性微球在酶固定化和实现靶向给药等方面的应用及存在的问题,对磁性微球的发展前景进行了展望。     

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。     

Preparation and characterization of chitosan-poly(acrylic acid) polymer magnetic microspheres

A modified method to prepare chitosan-poly(acrylic acid)(CS-PAA) polymer magnetic microspheres was reported in this paper. First, via self-assembly of positively charged CS and negatively charged Fe₃O₄ nanoparticles, magnetic CS cores with a large amount of Fe₃O₄ nanoparticles were successfully prepared. Subsequently, the AA monomers were polymerized on the magetic CS cores based on the reaction system of water-soluble polymer-monomer pairs. These polymer magnetic microspheres had a high Fe₃O₄ loading content, and showed unique pH-dependent behaviors on the size and zeta potential. From the magnetometer measurements data, the CS-PAA polymer magnetic microspheres also had superparamagnetic property as well as fast magnetic response. A continuous release of the entrapped ammonium glycyrrhizinate in such polymer magnetic microspheres occurred, which confirmed the potential applications of these microspheres for the targeted delivery of drugs.     

磁性微球的制备及其在水处理中的应用

概述了磁性微球的制备方法,同时对水处理用磁性微球的特点及其近年来在水处理中有机物检测、吸附剂和絮凝剂、固定化酶及微生物固定化载体方面的应用现状进行了详细介绍,提出了该领域磁性微球今后的研究方向。     

一种新型两亲性聚合物的合成研究

合成了一种新型的两亲性共聚物(丙烯酰胺/醋酸乙烯酯/丙烯酸丁酯,AM/VAc/BA),探讨了在该共聚物合成过程中AM用量和VAc与BA的配比对其表面张力、离心稳定性、乳化性及发泡力的影响,并对该三元共聚物P(AM/VAc/BA)的结构进行表征。结果表明,傅立叶红外光谱(FT-IR)分析在1 680 cm-1~1 620 cm-1处无C=C伸缩振动吸收峰出现,说明体系反应较彻底;差示扫描量热(DSC)分析得共聚物的玻璃化转变温度为37.6℃。     

铅离子印迹聚合物微球的制备及其吸附性能研究

以Pb2+为模板,甲基丙烯酸(MAA)为功能单体,乙二醇二甲基丙烯酸酯(EDMA)为交联剂,十二烷基苯磺酸钠(SDBS)为分散剂,采用乳液悬浮聚合法制备了铅离子印迹聚合物微球。通过静态平衡吸附实验和Scatchard分析法研究了聚合物微球的吸附性能和选择性。结果表明,铅离子印迹聚合微球能有效去除溶液中的铅离子,最大吸附容量为15.29 mg/g。在竞争离子Cd2+存在的溶液中,铅离子印迹聚合物微球呈现出对铅离子的高选择性。Pb2+/Cd2+的识别因子为19.01,结合位点的离解常数Kd=35.61 mg/L,最大表观结合量Qmax=25.19 mg/g。     

高分子微球的合成及其在密封剂中的应用

以亲水性4-乙烯基吡啶(4-Vp)为微球的壳层单体、苯乙烯(St)为微球的核层单体,采用一步无皂乳液聚合法制备了PS-P4V P[聚苯乙烯-聚(4-乙烯基吡啶)]微球;然后在该高分子微球表面覆盖了一层有机硅,合成了有机-无机杂化PS-P4VP-Si[有机硅包覆的聚苯乙烯-聚(4-乙烯基吡比啶)]微球;最后分别将两种微球与聚硫橡胶共混,制备相应的聚硫密封剂。研究结果表明:PS-P4VP、PS-P4VP-Si微球大小均一,两者粒径分别为290 nm和350 nm;两种微球分别作为聚硫密封剂的填料,既能提升密封剂的性能,又能降低密封剂本身的密度(比常规密封剂降低了15%～20%);同时,这两种微球填充的聚硫密封剂具有艮好的耐热性能和耐介质性能,特别是PS-P4VP-Si微球的综合性能更优异。     

磁性高分子微球的制备及其应用

介绍了有机高分子与磁性氧化铁复合的制备方法,总结了磁性高分子微球在废水处理、生物工程方面的应用,并对其发展趋势做了展望。     

硅烷化胺基磁性微球的合成与表征

采用溶液聚合法制备具有良好悬浮性和磁响应性的硅烷化胺基磁珠,对胺基磁性微球的形貌、结构、悬浮稳定性和磁响应性进行表征.研究结果显示,硅烷化胺基磁性微球的平均粒径为15nm,粒径分布比较均匀,近似为球形的壳核结构,核为磁性基质,壳为3-胺基丙基三乙氧基硅烷;将硅烷化胺基磁珠用于悬浮稳定性研究表明,磁微球具有较好的悬浮稳定...     

两亲性超支化聚酯-酰胺的制备及其性能

引言 在同一分子中,既含有亲水性链段,又含有疏水性链段的聚合物称为两亲性聚合物,这种聚合物的凝聚态常具有多相结构,并对不同极性的化合物都具有一定的亲和力,这种独特的性质就使其既不同于低分子表面活性剂也异于一般的离子聚合物.带有亲水性支链的两亲性聚合物具有很大的应用潜能.可以用作乳液和分散体的稳定剂,颜料及塑料的表面改性剂,高分子材料的助剂及改性剂等[1-2].     

改性磁性壳聚糖微球的制备、表征及性能研究

以(NH4)2Fe(SO4)2.6H2O、NH4Fe(SO4)2.12H2O和壳聚糖为原料,经羟丙基化、胺基化,采用一步包埋法制备了一种新型的多胺基化磁性壳聚糖微球。通过正交实验法确定了磁性微球的最佳制备条件,即搅拌速度1200r/min,壳聚糖用量3.0g,环氧氯丙烷用量2.5mL,乙二胺用量2.5mL。并用IR、TG、XRD和SEM对其结构及形貌进行了表征。结果表明,Fe3O4磁性粒子已包埋了一层胺基化壳聚糖。磁性微球胺基含量为2.302mmol/g;呈较规则的球形,平均粒径为209nm,且具有顺磁性和良好的耐酸性。     

Preparation and characterization of amphiphilic starch nanocrystals

In this article, amphiphilic starch nanocrystals were synthesized by graft copolymerization of starch nanocrystals with styrene in aqueous emulsion system. The starch nanocrystals of size around 50 nm were used, which were prepared by acid hydrolysis of corn starch. The structure of starch‐g‐polystyrene nanocrystals was characterized by Fourier transform infrared and ¹H nuclear magnetic resonance (¹H NMR). The crystalline structure as well as its particle morphology was studied by X‐ray diffraction and scanning electron microscopy, respectively. The results indicated that the amphiphilic starch nanocrystals obtained exhibit the size around 80–100 nm. Its crystalline structure is basically not changed after grafting polystyrene suggested that the polystyrene was essentially grafted on the surface of starch nanocrystals. Wettability experiments indicated that the prepared starch‐g‐polystyrene nanocrystals can be uniformly dispersed both in water phase and oil phase revealing excellent amphiphilicity. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

Preparation of polymer microspheres with a rosin moiety from rosin ester,styrene and divinylbenzene

Rosin was reacted with hydroxyethyl methacrylate to produce a macromonomer. This macromonomer was used to partly replace styrene for the novel preparation of polymer microspheres with divinylbenzene via suspension polymerization. Orthogonal experiments were conducted to analyze the factors influencing the particle size, particle size distribution, swelling ratio and degree of crosslinking of the polymer microspheres. Fourier transform IR spectroscopy, thermogravimetry and scanning electron microscopy were used to examine the structures, thermal properties and morphologies, respectively, of the polymer microspheres. The results showed that the amount of dispersant had the greatest influence on particle size and distribution. On the other hand, the monomer ratio greatly influenced the swelling ratio and degree of crosslinking of the polymer microspheres. The decomposition temperature of the polymer microspheres increased upon introduction of the rosin moiety into the product. Open pores were abundant on the surface of the polymer microspheres due to the existence of the porogen, which provided a base for adsorption and separation. The present study opens a novel route for using naturally occurring rosin. Copyright © 2012 Society of Chemical Industry     

Preparation of polymer/silica/polymer tri-layer hybrid materials and the corresponding hollow polymer microspheres with movable cores

Tri-layer poly(methacrylic acid-co-ethyleneglycol dimethacrylate)/silica/poly(ethyleneglycol dimethacrylate) (P(MAA-co-EGDMA)/SiO₂/PEGDMA) and P(MAA-co-EGDMA)/SiO₂/polydivinylbenzene hybrid microspheres were prepared by distillation precipitation polymerization of ethyleneglycol dimethacrylate (EGDMA) and divinylbenzene (DVB) in the presence of 3-(methacryloxy)propyl trimethoxysilane (MPS)-modified P(MAA-co-EGDMA)/SiO₂ microspheres as the seeds. The polymerization of EGDMA and DVB was performed in neat acetonitrile with 2,2′-azobisisobutyronitrile (AIBN) as initiator to coat the MPS-modified P(MAA-co-EGDMA)/SiO₂ seeds through the capture of EGDMA and DVB oligomer radicals with the aid of vinyl groups on the surface of modified seeds in the absence of any stabilizer or surfactant. Monodisperse P(MAA-co-EGDMA)/SiO₂ core-shell microspheres were synthesized by coating of a layer of silica onto P(MAA-co-EGDMA) microspheres via a sol-gel process, which were further grafted by MPS incorporating the reactive vinyl groups onto the surface to be used as the seeds for the construction of hybrid microspheres with tri-layer structure. Hollow poly(ethyleneglycol dimethacrylate) (PEGDMA) and poly(divinylbenzene) (PDVB) microspheres with movable P(MAA-co-EGDMA) core were subsequently developed after the selective etching of the silica mid-layer from the tri-layer hybrid microspheres in hydrofluoric acid. The morphology and structure of the tri-layer polymer hybrids and the corresponding hollow polymer microspheres with movable P(MAA-co-EGDMA) core were characterized by transmission electron microscopy (TEM), Fourier transform infrared spectra and X-ray photoelectron spectroscopy (XPS).     

双亲性聚合物调理剂在护发素中的应用研究

研究了双亲性聚合物作为调理剂成分在无硅油护发素中的应用。以溶液自由基聚合法合成了双亲性无规聚合物聚(苯乙烯-co-丙烯酸)。利用阳离子表面活性剂山嵛基三甲基氯化铵与聚合物之间的阳离子-π电子作用,将双亲性无规共聚物聚(苯乙烯-co-丙烯酸)吸附到头发表面起到顺滑作用。通过调节聚合物中苯环与山嵛基三甲基氯化铵的摩尔比、山嵛基三甲基氯化铵的浓度以及使用量,制备具有优异梳理性能的护发素,对护发素效果进行评价,并与含硅护发素进行比较。结果表明:最优条件下,双亲性聚合物在头发上的残留量为102μg/g头发;在护发素中添加双亲聚合物后能够显著改善湿梳理性能,其湿梳性优于市售含硅护发素;经护发素处理后的头发毛鳞片规整、无翘起,且双亲聚合物在头发上无累积效应。