【摘要】 以苯乙烯为单体,甲基丙烯酰氧乙基-N-辛基二甲基溴化铵为功能单体,偶氮二异丁基脒盐酸盐为引发剂,采用两步投料无皂乳液聚合方法,合成了单分散表面带正电荷的聚苯乙烯胶体粒子。在低离子强度的水溶液中,该胶体粒子可以通过表面电荷的静电排斥作用,自组装成胶体晶体阵列并产生Bragg衍射,随着乳液固含量的降低,Bragg衍射波长红移。更多还原

【Abstract】 Monodispersed,highly positive charged nanoparticles were prepared by a two-step emulsifier-free emulsion copolymerization with styrene and N-octyl-N,N-dimethyl-ammonioethyl methacrylate bromide.The morphology and particle size of polymeric nanoparticles were studied by scanning electron microscopy and dynamic laser light scattering,and the surface charge density of nanoparticles were examined by conductometric titration.These particles could spontaneously self-assemble into non-close-packed crystalline colloidal arrays which Bragg diffracts light.With the decrease of concentration of CCAs,there was a red shift in the Bragg diffraction wavelength.更多还原