亲/疏水不对称空心聚合物微球制备及磁性粒子装载研究

首先将(马来酸酐-醋酸乙烯酯共聚物)核/(马来酸酐-二乙烯基苯共聚物)壳微球的壳层外表面酐基烷基溴化,然后将核溶蚀、壳层内表面酐基水解,制得内表面含亲水羧基、外表面含烷基溴、具有微孔(Barrett-Joyner-Halenda平均孔径14.9nm)的空心聚合物微球.以此空心微球为微反应器,使Fe2+和Fe3+通过球壁...

PREPARATION OF HOLLOW POLYMER MICROSPHERES WITH HYDROPHILIC/HYDROPHOBIC ASYMMETRIC SURFACE AND LOADING OF MAGNETIC NANO-PARTICLES

As a microreactor,hollow microspheres could be used to load magnetic nanoparticles.Asymmetric hollow polymeric microspheres with micropores of 14.9 nm,alkyl bromine groups on exterior wall and carboxyl groups on interior wall were produced through three steps:(a) synthesis of the core-shell microparticles with copolymer of maleic anhydride(MAn) and divinyl benzene(DVB) as the shell,and copolymer of maleic anhydride(MAn) and vinylacetate(VAc) as the core;(b) surface bromizing of the core-shell microparticles by reaction with dibromoethane;(c) etching of the cores with acetone,and followed by the hydrolyzing of the anhydride groups on interior wall.Fe3O4 magnetic nanoparticles were loaded into the cavity of prepared hollow polymeric microspheres by two steps: first,Fe2+ and Fe3+ were infiltrated into the hollow microspheres and selective adsorbed on the interior wall under the effect of carboxyl groups;secondly,in appropriate condition,coprecipitation were carried out to obtain Fe3O4 magnetic nanoparticles.In addition,influences of parameters relating to the above mentioned reaction,such as the mole ratio of Fe2+ and Fe3+,reaction temperature and reaction time,on the saturation magnetization of the magnetic microspheres were investigated.The results show that,the optimum reaction conditions to the balance of loading selectivity and value of saturation magnetization were as follow: molar ratio of Fe2+ and Fe3+ was 2/3,reaction temperature was 80℃ and reaction time was 1.5 h,for obtained the best value of saturation magnetization 12.34 emu/g.