A novel diblock copolymer based on poly(N-vinylcarbazole) PVK and poly(p-phenylenevinylene) (PPV) precursor was synthesized by oxidative cross-linking. The grafting of PPV with PVK moieties was elucidated by infrared absorption analysis. A structural study by X-ray diffraction and a morphological study of the copolymer by scanning and transmission electron microscopy reveal a multiscale one-dimensional self-organization both at the molecular and at the sub-micrometric level. The resulting copolymer exhibits original optical properties compared to those of PVK and PPV ones and presents an improved thermal behavior. (c) 2013 Wiley Periodicals, Inc.