PDMS behaviour under confinement in strongly segregated mesophases of PS-PDMS diblock copolymers
1 Centro de Física de Materiales, Centro Mixto (CSIC-UPV/EHU) y Departamento de Física de Materiales, Universidad del País Vasco (UPV/EHU), Apartado 1072, 20080 San Sebastián, Spain
2 Donostia International Physics Center, Paseo Manuel de Lardizabal 4, 20018 San Sebastián, Spain
a e-mail: firstname.lastname@example.org
Revised: 14 September 2010
Published online: 12 November 2010
A dynamic and thermal investigation by means of broadband dielectric spectroscopy and temperature modulated differential scanning calorimetry on the PDMS behaviour in several highly segregated diblock copolymers with varying PDMS molecular weight and volume fraction is presented. The mesophase morphology of these diblock copolymers has been characterized by means of transmission electron microscopy and small angle X-ray scattering. It is found that whereas the lamellar morphology (1D confinement) does not affect significantly the PDMS properties, in the case of the cylindrical (2D confinement) and spherical (3D confinement) segregations of the PDMS component in the PS matrix noticeable effects are evident, such as a strong reduction of the PDMS glass-transition temperature and a strong decrease (even suppression) of PDMS crystallinity ratio.
© EDP Sciences, Springer-Verlag, 2010