【摘要】 以可聚合单体对苯乙烯磺酸钠(Na SS)作稳定剂,采用两步阴离子稳定分散聚合法,制备了单分散聚苯乙烯-丙烯腈P(St-AN)共聚微球,研究了丙烯腈单体加入时间对聚合物微球粒径及其分布的影响。并以微球为模板通过化学沉积法得到了分布均匀、单分散草莓状的Ag/P(St-AN)复合微球。通过傅里叶红外光谱、X射线衍射、扫描电镜和紫外-可见光谱对复合微球的组成、结构、形貌及催化性能进行了表征。结果表明,反应后1~3h补加丙烯腈可以得到600~800 nm单分散模板微球。得到的Ag/P(St-AN)复合微球表面具有较均一的结构,纳米银粒子具有面心立方结构,在微球表面有较好的分散性及稳定性,同时Ag/P(St-AN)复合微球对硼氢化钠(Na BH4)还原对硝基苯酚(4-NP)具有较高的催化活性。更多还原

【Abstract】 Monodisperse polymer microspheres P( St-AN) were prepared through two-steps polymerization stabilized with polymerizable anion-charged monomer Sodium Styrene Sulfonate( Na SS).The influence of acrylonitrile dropping time on particle size and dispersity were discussed. Using the P( St-AN) particles as template,raspberry-like Ag /P( St-AN) composites were obtained by chemical deposition. Composition,structure,morphology and catalytic performance of the composite particles were characterized by fourier transform infrared spectroscopy,X-ray diffraction,scanning electron microscopy,and UV-visible spectroscopic techniques. The results revealed that the P( St-AN) template particles were uniform spherical particles when the acrylonitrile were dropped 1 ~ 3 h after the reaction beginning. The particle size was between 600 nm and 800 nm. The obtained Ag / P( St-AN) was of uniform structure and Ag nanoparticles of face centered cubic crystal structure was well coated on the surface of the particles with good dispersity and stability. The Ag / P( St-AN) composite particles were used as the catalyst in 4-nitrophenol reduction to 4-aminophenol with Na BH4 as the reducer,and the reduction was significantly enhanced.更多还原