Chen Kaiqiang, Liang Dehai, Tian Jia, Shi Linqi, Zhao Hanying
Key Laboratory of Functional Polymer Materials, Ministry of Education, Department of Chemistry, Institute of Polymer Chemistry, Nankai University, Tianjin, P. R. China.
J Phys Chem B. 2008 Oct 9;112(40):12612-7. doi: 10.1021/jp803216s. Epub 2008 Sep 13.
Herein we describe a new strategy for producing micelles with mixed coronal chains. This method involves attachment of an atom transfer radical polymerization (ATRP) initiator at the interface of a micelle and preparation of poly(2-(dimethylamino)ethyl methacrylate) (PDMAEMA) brushes at the interface by a "grafting from" method. Poly(ethylene glycol)- block-polystyrene (PEG- b-PS) diblock copolymer was achieved by ATRP. After the sulfonation reaction PS blocks were partly sulfonated. In aqueous solution at low pH the sulfonated block copolymer self-assembled into micelles with PS cores and PEG coronae and sodium 4-styrenesulfonate groups were distributed at the interfaces of the micelles. An ATRP initiator consisting of a quaternary ammonium salt moiety and a 2-bromo-2-methyl propionate moiety was ion exchanged onto the interface of the micelle. ATRP of DMAEMA was initiated at the interface, and micelles with PEG/PDMAEMA mixed coronal chains were prepared by ATRP. The structures of the micelles were characterized by dynamic light scattering (DLS), transmission electron microscopy (TEM), and zeta potential measurements. The size and morphology of the micelles were controlled by pH in aqueous solution. At high pH, PDMAEMA brushes collapse, forming nanodomains on the surface of the micelles. PDMAEMA brushes in the coronae of the micelles could be used as a template for preparation of gold nanoparticles.
在此,我们描述了一种制备具有混合冠状链胶束的新策略。该方法包括在胶束界面连接原子转移自由基聚合(ATRP)引发剂,并通过“从界面生长”法在界面制备聚(甲基丙烯酸2-(二甲氨基)乙酯)(PDMAEMA)刷。通过ATRP制备了聚乙二醇-嵌段-聚苯乙烯(PEG-b-PS)二嵌段共聚物。经过磺化反应后,PS嵌段部分磺化。在低pH值的水溶液中,磺化的嵌段共聚物自组装成具有PS核和PEG冠的胶束,4-苯乙烯磺酸钠基团分布在胶束界面。由季铵盐部分和2-溴-2-甲基丙酸酯部分组成的ATRP引发剂通过离子交换到胶束界面。在界面引发DMAEMA的ATRP反应,通过ATRP制备了具有PEG/PDMAEMA混合冠状链的胶束。通过动态光散射(DLS)、透射电子显微镜(TEM)和zeta电位测量对胶束结构进行了表征。胶束的尺寸和形态在水溶液中受pH值控制。在高pH值下,PDMAEMA刷坍塌,在胶束表面形成纳米域。胶束冠中的PDMAEMA刷可作为制备金纳米颗粒的模板。