紫外辐照法制备载银P(St-co-MMA)复合微球的研究

Preparation of Ag nanoparticles located P(St-co-MMA) composite microspheres by UV light

以聚乙烯吡咯烷酮(PVP)为分散剂,2,2-二甲氧基-2-苯基苯乙酮(BDK)为引发剂,在乙醇和水(V(乙醇)/V(水)=7/3)的混合介质中,由紫外(UV)光引发苯乙烯(St)和甲基丙烯酸甲酯(MMA)进行分散共聚,研究了影响P(St-co-MMA)收率及其微球粒径的因素;在微球分散液中加入一定浓度的AgNO3,经UV原位催化Ag+还原,制备出了负载有Ag纳米颗粒的P(St-co-MMA)复合微球。用透射电子显微镜(TEM)、激光光散射(LLS)和X射线衍射(XRD)对微球的粒径及Ag纳米颗粒的负载情况进行了表征,发现P(St-co-MMA)微球的粒径均一,可控制在500～800nm之间,Ag纳米颗粒较均匀地负载于微球的表面,平均大小为20nm。

P（St-co-MMA） microspheres were prepared by photoinitiated dispersion copolymerization of styrene（St） with methyl methacrylate（MMA） in a mixture of ethanol and water（V（ethanol）/V（water）=7/3） using 2,2-dimethoxy-2-phenylacetophenone（BDK） and polyvinylpyrrolidone（PVP） as the initiator and stabilizer,respectively.The effects of reaction time,the monomer ratio of St and MMA,amount of PVP and light intensity on the yield and diameter of P（St-co-MMA） microspheres were studied.Ag＋ ions were reduced to silver by UV light using AgNO3 as metal sources in the presence of P（St-co-MMA） microspheres.At the same time,Ag nanoparticles were located to the surfaces of P（St-co-MMA） microspheres.The resulting composite microspheres were characterized by transmission electron microscopy（TEM）,laser light scattering（LLS） and X-ray diffractometry（XRD）.It was found that the diameter of P（St-co-MMA） microspheres can be controlled in range from 500 to 800nm.The composite materials of silver nanoparticles/ P（St-co-MMA） microspheres were successfully synthesized.The mean diameter of silver nanoparticles was about 20nm.