Eur. Phys. J. E (2003) 12: 121-125
https://doi.org/10.1140/epjed/e2003-01-028-x

Segmental order and dynamics of polymer chains confined in block copolymer lamellar mesophases: NMR and dielectric relaxation studies

¹ Laboratoire de Physique des Solides (CNRS-UMR 8502), Université Paris-Sud, 91405 Orsay, France
² Departamento de Física de Materiales (UPV/EHU) y Unidad de Física de Materiales Centro Mixto (CSIC-UPV/EHU), Facultad de Química, Apartado 1072, 20080 San Sebastián, Spain
³ Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
⁴ Physico-Chimie Curie (CNRS-UMR 168), Institut Curie, 11 rue Pierre et Marie Curie, 75005 Paris, France
⁵ Institut Charles Sadron (CNRS-UPR 22), 6 rue Boussingault, 67083 Strasbourg, France

Received: 20 December 2002
Published online: 5 November 2003

Abstract

The PDMS lamellar sublayers of a poly(styrene)-poly(dimethylsiloxane) diblock (PS-PDMS) and PS-PDMS-PS triblocks are investigated by NMR and dielectric spectroscopy. Some segments of the confined PDMS chains display anisotropic orientational fluctuations along the interfaces with the PS glassy blocks, whereas the others display fluctuations rather parallel to the lamellae normal. This coexistence results from a competitive ordering effect induced by the glassy interfaces and the chain-end anchoring junctions. The distribution of PDMS relaxation times within the sublayers is also examined: in particular, a slowing down of the segmental motions, together with a broadening of this distribution, are detected.