Copolymer Synthesis Synthesis and Self-Assembly of Rod–Rod Hybrid Poly(g-benzyl l-glutamate)-block-Polyisocyanide Copolymers** Alexander Kros,* Wim Jesse, Gerald A. Metselaar, and Jeroen J. L. M. Cornelissen* Dedicated to Professor Roeland J. M. Nolte on the occasion of his 60th birthday The synthesis and self-assembly of rod–rod block copolymers is still a pristine area in the field of polymer chemistry. [1,2] Nevertheless, it promises applications, for example, as bio- sensors, scaffolds for tissue engineering, and materials with new properties. [3] To our knowledge only two publications on rod–rod block copolymers have been published till now. Deming and co-workers synthesized polyleucine– poly(hydroxylated glutamate), which formed large vesicular systems in water. [4] This block copolymer was prepared by an elegant method developed by this group for the living polymerization of N-carboxy anhydrides of amino acids (NCAs) using a 2,2’-bipyridylnickel(0)(1,5-cyclooctadiene) [Ni(bpy)(cod)] complex as the catalyst. [5] This synthetic method enabled not only the preparation of the above system but also of a host of block polypeptides. [6] The synthesis and self-assembly of hybrid block copolymers containing a p-conjugated polymer and peptide segment was described by Jenekhe and Kong. [7] Upon changing the secondary conformation (that is, helix versus coil) of the peptide segment in a polyfluorene–poly(g-benzyl glutamate), different types of nanosized assemblies were observed. Cornelissen and co-workers studied the polymerization and self-assembly of isocyanopeptide polymers [8] and rod–coil block copolymers containing this peptidomimetic segment. [9] These peptide-derived polyisocyanides have unique proper- ties that result from the intramolecular b-sheetlike hydrogen- [*] Dr. A. Kros, W. Jesse Department of Soft Matter Chemistry Leiden Institute of Chemistry Leiden University PO Box 9502, 2300RA Leiden (The Netherlands) Fax: (+ 31)71-527-4397 E-mail: a.kros@chem.leidenuniv.nl G. A. Metselaar, Dr. J. J. L. M. Cornelissen Department of Organic Chemistry Institute for Molecules and Materials Radboud University Nijmegen Toernooiveld 1, 6525ED Nijmegen (The Netherlands) Fax: (+ 31)24-365-2929 E-mail: j.cornelissen@science.ru.nl [**] The Council for the Chemical Sciences of the Netherlands Organization for Scientific Research is acknowledged for Veni Innovative Research Grants to A.K. and J.J.L.M.C. We are grateful to Prof. Hans Fraaije and Dr. P. Budzelaar for stimulating discussions. Supporting information for this article is available on the WWW under http://www.angewandte.org or from the author. Angewandte Chemie 4349 Angew. Chem. Int. Ed. 2005, 44, 4349 –4352 DOI: 10.1002/anie.200500877 # 2005 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim