Document VersionPublisher's PDF, also known as Version of Record (includes final page, issue and volume numbers)Please check the document version of this publication:• A submitted manuscript is the author's version of the article upon submission and before peer-review. There can be important differences between the submitted version and the official published version of record. People interested in the research are advised to contact the author for the final version of the publication, or visit the DOI to the publisher's website.• The final author version and the galley proof are versions of the publication after peer review.• The final published version features the final layout of the paper including the volume, issue and page numbers. Link to publication Citation for published version (APA):Appel, R., Fuchs, J., Tyrrell, S. M., Korevaar, P. A., Stuart, M. C. A., Voets, I. K., ... Besenius, P. (2015). Steric constraints induced frustrated growth of supramolecular nanorods in water. Chemistry -A European Journal, 21(52), 19257-19264. DOI: 10.1002/chem.201503616 General rights Copyright and moral rights for the publications made accessible in the public portal are retained by the authors and/or other copyright owners and it is a condition of accessing publications that users recognise and abide by the legal requirements associated with these rights.• Users may download and print one copy of any publication from the public portal for the purpose of private study or research.• You may not further distribute the material or use it for any profit-making activity or commercial gain • You may freely distribute the URL identifying the publication in the public portal ? Take down policyIf you believe that this document breaches copyright please contact us providing details, and we will remove access to the work immediately and investigate your claim. Ilja K. Voets, [d, f] Monika Schçnhoff, [c] and Pol Besenius* [a, b] Abstract: Au nique example of supramolecular polymerisation in waterb ased on monomers with nanomolara ffinities, which yield rod-like materials with extraordinarily high thermodynamic stability, yet of finite length, is reported. A small libraryo fc harge-neutral dendritic peptide amphiphiles was prepared,w ith ab ranched nonaphenylalanine-based core that was conjugated to hydrophilic dendrons of variable steric demand. Below ac ritical size of the dendron,the monomers assemble into nanorod-like polymers,w hereas for larger dendritic side chainsf rustratedg rowth into near isotropic particles is observed.T he supramolecular morphologies observed by electron microscopy,X -ray scattering and diffusion NMR spectroscopy studies are in agreement with the mechanistic insights obtained from fitting polymerisationp rofiles:n on-cooperative isodesmic growth leads to degrees of polymerisation that matcht he experimentally determined nanorod contour lengths of close to 70 nm. The reportedd esignsf or aqueous self-assembly into well-defined anisotropic particles has promising potentialf or biomedical applicat...