Self-assembled polymer nanocomposites are a promising class of advanced materials with unique structures and tunable properties. Control over the spatial arrangement and ordering of the constituent material is essential to developing composites with defined morphologies and properties. Here I report the synthesis of poly(n-butyl acrylate-b-styrene) from the surface of functionalized montmorillonite clay (MMT) via activators regenerated by electron transfer (ARGET) atom transfer radical polymerization (ATRP). The application of ARGET ATRP to MMT surface-initiated polymerizations results in a robust and reproducible method for synthesizing well-defined tethered block copolymers. The chosen block copolymer architecture of the composite materials resembles that of a thermoplastic elastomer, with glassy PS domains sandwiching the rubbery PnBA domain, which is divided by the clay platelets. The structure was characterized by several techniques that examine the self-assembly and degree of clay exfoliation. Preliminary analysis of the material properties indicates elastomeric behavior. / text