Preparation and colloidal stability of monodisperse magnetic polymer particles
Preparation and colloidal stability of monodisperse magnetic polymer particles
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DOI：
10.1016/j.jcis.2005.03.073
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发表时间：
2005-09-15
影响因子：
9.9
通讯作者：
Konno, M
中科院分区：
文献类型：
--
作者：
Gu, SC;Onishi, JY;Konno, M
研究了先前提出的用于生产单分散、亚微米尺寸的磁性聚合物颗粒的方法。该方法采用无皂乳液聚合，在此过程中，Fe3O4 磁性纳米颗粒异质凝结到沉淀的聚合物核上。为了将磁性颗粒化学固定到聚合物核上，在与甲基丙烯酰氧基丙基三甲氧基硅烷的初步表面改性反应中，在 Fe3O4 颗粒上引入乙烯基，并将甲基丙烯酰氧基丙基二甲氧基硅烷（MPDMS）添加到无皂乳液聚合的反应体系中。通过在聚合过程中添加离子单体对苯乙烯磺酸钠（NaSS），提高了磁性聚合物颗粒的胶体分散稳定性。聚合反应采用苯乙烯单体和过硫酸钾引发剂，NaSS 浓度（0-2.4 x 10(-3) M）、NaSS 添加时间（60-80 分钟）和单体浓度（0.3-0.6 M）范围内，固定浓度为 1.6 x 10(-2) M 引发剂和 1.3 x 10(-2) M MPDMS，pH 4.5，用缓冲系统调节。 [CH3COOH]/[NaOH]。聚合过程中添加NaSS可以保持聚合过程中磁性聚合物颗粒的分散稳定性。反应条件的选择使得能够制备胶体稳定的亚微米尺寸的磁性聚合物颗粒，其分布变异系数小于单分散性的标准标准10%。 (c) 2005 Elsevier Inc. 保留所有权利。
A previously proposed method was examined for producing monodisperse, submicrometer-sized magnetic polymer particles. The method applies soap-free emulsion polymerization during which Fe3O4 magnetic nanoparticles are heterocoagulated onto precipitated polymer nuclei. To chemically fix the magnetic particles to the polymer nuclei, vinyl groups were introduced on the Fe3O4 particles in a preliminary surface modification reaction with methacryloxypropyltrimethoxysilane, and methacryloxypropyldimethoxysilane (MPDMS) was added to reaction systems of the soap-free emulsion polymerization. The colloidal dispersion stability of magnetic polymer particles was improved by the addition of an ionic monomer, sodium p-styrenesulfonate (NaSS), during the polymerization. The polymerizations were carried out with styrene monomer and potassium persulfate initiator in ranges of NaSS concentrations (0-2.4 x 10(-3) M), NaSS addition times (60-80 min), and monomer concentrations (0.3-0.6 M) at fixed concentrations of 1.6 x 10(-2) M initiator and 1.3 x 10(-2) M MPDMS for pH 4.5 adjusted with a buffer system of [CH3COOH]/[NaOH]. The addition of NaSS during the polymerization could maintain the dispersion stability of magnetic polymer particles during the polymerization. Selection of the reaction conditions enabled the preparation of colloidally stable, submicrometer-sized magnetic polymer particles that had coefficients of variation of distribution smaller than the standard criterion for monodispersity, 10%. (c) 2005 Elsevier Inc. All rights reserved.