The present invention is broadly concerned with novel directed self-assembly compositions, processes utilizing those compositions, and the resulting structures that are formed. The composition comprises a block copolymer of polystyrene and a polymethylmethacrylate block with polylactic acid side chains (“PS-b-P(MMA-LA)”). The block copolymer is capable of crosslinking and micro-phase separating into lines and spaces measuring about 10-nm or smaller with sub-20 nm L0 capability. Additionally, PS-b-P(MMA-LA) can be thermally annealed without a top-coat for simpler processing than the prior art. The polylactic acid side chains also increase the etch rate of the poly(methylmethacrylate) block when exposed to oxygen plasma, as well as lower the Tg.