A Novel Crystallization Scheme in Poly[styrene-block-(ferrocenyl dimethylsilane)] Diblock Copolymers

Isothermal crystallization of the poly(ferrocenyl dimethylsilane) (PFDMS) segments in a poly[styrene-block-(ferrocenyl dimethylsilane)] (PS-b-PFDMS) diblock copolymer of lamellar micro-morphology has been investigated. The PFDMS is shown to crystallize in a confined and grain-by-grain fashion. Here a 'grain' is defined as an ensemble of stacked lamellae wherein the PFDMS crystallization spreads quickly but stops at its surroundings. Such crystallization propagates not only along the PFDMS lamellae but across the amorphous PS layers as well. We suggest that conformational changes in the PS as induced by the PFDMS crystallization ('squeezing transfer') are responsible for the latter pathway of the crystallization's spread.