AbstractIn this article we further investigate our recently devised method for folding polymer chains into nanoparticles using intramolecular, supramolecular interactions. Specifically, we show a direct relationship between molecular weight of the parent chain and size of the folded nanoparticle. This is investigated both analytically via the separation and subsequent characterization of a polydisperse nanoparticle sample into high and low molecular weight fractions, and by examining a family of poly(norbornenes) deliberately prepared with varying molecular weights. With these polymer nanoparticles in hand their assembly on surfaces is studied where larger structures are formed as a result of the interplay between the movement of the nanoparticles on the surface and the evaporation of solvent. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2010