Nanomedicine and Advanced Technologies Research Center, Gazi University, 06830 Ankara, Turkey.
J Colloid Interface Sci. 2010 Apr 15;344(2):528-32. doi: 10.1016/j.jcis.2010.01.041. Epub 2010 Jan 18.
Surfactant-free emulsion polymerization (SFEP) is a well-known technique for the production of polymeric nanoparticles that does not require post-synthetic cleaning steps. Obtaining hydrophobic particles at sub-100 nm scale, however, is quite challenging with this polymerization method. Here, we demonstrate a single step synthetic approach that yields poly(methylmethacrylate) (PMMA) nanoparticles with controlled sub-100 nm size and relatively high resultant solid content. Dynamic light scattering (DLS) was used for the particle characterization. Spherical and uniformly sized nanoparticles were confirmed by atomic force microscopy (AFM) and scanning electron microscopy (SEM). Acetone was used as a cosolvent in order to obtain monodisperse sub-100 nm diameter particles. Stable PMMA nanoparticle dispersions were obtained for all formulations where the persulfate initiator causes the negative charges on the particle surface. The effects of acetone, monomer and initiator concentration were studied to optimize average particle hydrodynamic diameter and polydispersity index of the final particles. Non-crosslinked monodisperse PMMA nanoparticles (polydispersity index less than 0.05) with diameters from 32 nm to 72 nm were synthesized by using this method.
无表面活性剂乳液聚合（SFEP）是一种众所周知的生产聚合物纳米粒子的技术，不需要合成后的清洗步骤。然而，用这种聚合方法在亚 100nm 尺度下获得疏水性颗粒是相当具有挑战性的。在这里，我们展示了一种一步合成方法，该方法可以得到具有可控亚 100nm 尺寸和相对较高的最终固体含量的聚甲基丙烯酸甲酯（PMMA）纳米粒子。通过动态光散射（DLS）对粒子进行了表征。原子力显微镜（AFM）和扫描电子显微镜（SEM）证实了球形和均匀尺寸的纳米粒子。为了获得单分散的亚 100nm 直径的粒子，使用了丙酮作为共溶剂。所有配方中均使用过硫酸盐引发剂在粒子表面产生负电荷，从而得到稳定的 PMMA 纳米粒子分散体。研究了丙酮、单体和引发剂浓度的影响，以优化最终粒子的平均粒子水动力直径和多分散指数。使用该方法合成了非交联的单分散 PMMA 纳米粒子（多分散指数小于 0.05），粒径从 32nm 到 72nm 不等。
