A novel method of dual patterning and sequential functionalization of block copolymers is proposed using a photocrosslinkable random copolymer film, poly(styrene-r-(tert-butyl acrylate)-r-(cinnamoyloxyethyl acrylate)). The tert-butyl esters of the block copolymer, polystyrene-block-poly(tert-butyl acrylate), coated on the patterned random copolymer film were sequentially deprotected to give carboxylic acids using an acid catalyst and heat treatment. The sequentially produced carboxylic acid patterns were used for the sequential patterning of gold nanoparticles as an example of potential applications.