DYNAMIC PROBE OF THE INTERFACE IN LAMELLAR FORMING NONLINEAR BLOCK-COPOLYMERS OF THE (BA)(3)B AND (BA)(3)B(AB)(3) TYPE - A DIELECTRIC-SPECTROSCOPY STUDY

Dielectric spectroscopy is employed in lamellar forming non-linear blo ck copolymers of the type (BA)(3)B and (BA)(3)B(AB)(3) based on polyis oprene (A) and polystyrene (B), at temperatures well below the order-t o-disorder transition temperature and below the glass transition tempe rature of the hard phase (polystyrene). We show here that dielectric s pectroscopy can be used as a tool to probe the interface in ordered bl ock copolymers with a basic triblock unit. Our estimate of the interfa cial width is based on the mobility of the junction points at the inte rface and compares favorably with the estimated thickness from thermod ynamics. (C) 1998 Elsevier Science B.V. All rights reserved.