原子转移自由基溶液聚合制备聚合物纳米粒子

Preparation of Polymer Nanoparticles by Homogeneous Solution Atom Transfer Radical Polymerization

使用2-氯丙酰氯对第四代聚丙烯亚胺树枝状大分子(DAB-32)进行改性,成功合成了树枝状大分子引发剂DAB-32-Cl,并使用红外光谱(FT-IR)、核磁共振光谱(1H-NMR)对引发剂的结构进行了表征。以此引发剂,CuCl/Bpy为催化剂,成功实现了丙烯酸(AA)和苯乙烯(St)的原子转移自由基(ATRP)溶液聚合,制备出树枝状大分子/聚丙烯酸和树枝状大分子/聚苯乙烯纳米粒子。采用光子相关光谱(PCS)和透射电子显微镜(TEM)对聚合物纳米粒子的形貌、粒径和粒径分布进行了表征,结果表明,合成的聚合物纳米粒子大小均一,小于121 nm,分散性较好。

Polypropylenimine dendrimer （DAB-32, generation 4.0） was converted into the macroinitiator DAB- 32-（21 via reaction with 2-chloropropionyl chloride. The structure of DAB-32-Cl was characterized by Fourier transform infrared spectrometry（FT-IR） and proton nuclear magnetic resonance spectroscopy （^1H-NMR）. Atom transfer radical polymerizations of AA and St were successfully performed respectively in homogeneous solution systems using the DAB-32-Cl/CuCl/Bpy as initiating system, and the dendrimer/PAA and dendrimer/PSt nanoparticles were obtained. The morphology, size and size distribution of the polymer nanoparticles were characterized by photon correlation spectroscopy （PCS） and transmission electron microscopy （TEM）. It is found that the diameters of polymer particles are smaller than 121 nm and monodisperse.