Title:
Crystallization and Physical Ageing of Poly (2-vinyl pyridine)-b
-poly(ethylene oxide) Diblock Copolymers
Languages of Item:
English
Abstract:
Summary: A set of melt miscible Poly(2-vinyl pyridine)-b-Poly(ethylene oxide) (P2VPb-PEO) block copolymers of different compositions were studied. Transmission electron microscopy shows phase separation in the materials during the crystallization process of the PEO block as crystalline lamellae are observed for all compositions evaluated. The isothermal crystallization kinetics of PEO is progressively retarded as the P2VP content in the copolymer increases, since P2VP hinders molecular mobility in the miscible amorphous phase. Polarized light optical microscopy demonstrated that the glassy P2VP block has a negative effect on the secondary nucleation of the PEO. Finally, physical ageing experiments performed in the glassy state of the amorphous mixed phase, at different ageing times, demonstrated that a nucleating effect can be induced in the glassy state as a consequence of the reorganization of the amorphous regions. This nucleating effect significantly alters the cold crystallization rate upon subsequent heating above the glass transition temperature. Copyright © 2010 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Authors:
Miguel Córdova
Arnaldo T. Lorenzo
Alejandro J. Müller
Panagiota Fragouli
Hermis Iatrou
Nikos Hadjichristidis
Journal:
Macromolecular Symposia
Keywords:
Amorphous phase; Amorphous regions; Cold crystallization; Crystalline lamella; Crystallization morphology; Crystallization process; Diblock copolymer; Glass transition temperature; Glassy state; Isothermal crystallization kinetics; Mixed phase; Molecular mobility; Nucleating effect; Physical ageing; Polarized light optical microscopies; Poly(2-vinyl pyridine); Poly(2-vinylpyridine) (P2VP); Secondary nucleation, Block copolymers; Copolymerization; Crystallization kinetics; Ethylene; Glass transition; Insecticides; Morphology; Optical microscopy; Organic polymers; Plastic products; Polyethylene oxides; Transmission electron microscopy, Phase separation
Main subject category:
Science
Official URL (Publisher):
DOI:
10.1002/masy.201050114
