Yan Jiajun, Pan Xiangcheng, Schmitt Michael, Wang Zongyu, Bockstaller Michael R, Matyjaszewski Krzysztof
Department of Chemistry and ‡Department of Material Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States.
Department of Chemistry and Department of Material Science and Engineering, Carnegie Mellon University, 5000 Forbes Avenue, Pittsburgh, Pennsylvania 15213, United States.
ACS Macro Lett. 2016 Jun 21;5(6):661-665. doi: 10.1021/acsmacrolett.6b00295. Epub 2016 May 17.
Well-defined polymer-inorganic hybrid materials were prepared via metal-free surface-initiated atom transfer radical polymerization (SI-ATRP) with 10-phenylphenothiazine (PhPTZ) as the photocatalyst and 2-bromo-2-phenylacetate initiator tethered to silica surfaces. Initiation efficiency and, hence, graft density were significantly enhanced by this very reactive initiator. The polymerization kinetics, effect of initiator structures, particle sizes, and catalyst concentrations were investigated. Well-defined hybrid particles were prepared at a low catalyst concentration (0.02 mol % or 0.1 mol % to monomer). Poly(methyl methacrylate) (PMMA) with number-average molecular weight of 3.65 × 10, dispersity of 1.43, and graft density of 0.60 chain/nm was grafted from the surface of silica nanoparticles. The hybrid materials were characterized with size exclusion chromatography (SEC), thermogravimetric analysis (TGA), dynamic light scattering (DLS), and transmission electron microscopy (TEM).
通过无金属表面引发原子转移自由基聚合（SI-ATRP）制备了结构明确的聚合物-无机杂化材料，其中以10-苯基吩噻嗪（PhPTZ）作为光催化剂，2-溴-2-苯基乙酸酯引发剂连接在二氧化硅表面。这种活性很高的引发剂显著提高了引发效率，进而提高了接枝密度。研究了聚合动力学、引发剂结构、粒径和催化剂浓度的影响。在低催化剂浓度（相对于单体为0.02 mol%或0.1 mol%）下制备了结构明确的杂化颗粒。从二氧化硅纳米颗粒表面接枝了数均分子量为3.65×10、分散度为1.43且接枝密度为0.60链/纳米的聚甲基丙烯酸甲酯（PMMA）。通过尺寸排阻色谱（SEC）、热重分析（TGA）、动态光散射（DLS）和透射电子显微镜（TEM）对杂化材料进行了表征。
