Poly(styrene-co-methacrylic acid) P(S-co-MAA) copolymer colloidal crystals were transformed to ordered porous arrays by selective dissolution using toluene as solvent.The atomic force microscopy (AFM) and scanning electron microscopy(SEM) were used to characterize the structure change during spherepore transforming process

and the AES was used to analyze the element content variety of the colloidal spheres before and after the conversion.The polystyrene core in the P(S-co-MAA) latex nanospheres first swelled

making the colloids conglutination.Then the bursting of the methacrylic acid shell led to it gradually dissolution

resulting in a porous structure.Owing to the liquidity of the macromolecule

the pores formed are irregular rounded.The surface element analysis indicates that when the polystyrenes in core are extracted from the colloidal spheres by solvent

they diffuse into the solvent

not fill in the interspaces among the spheres.In addition

the methacrylic acid riched on the colloidal surface has the function to fix and support the porous structure

but the structure could be ruined with long time immersion.