Nano- and Micromechanics of Crystalline Polymers
Chapitre d'ouvrage scientifique
Date
2009Résumé
It is currently thought that crystalline polymers consists of lamellar crystals which are separated from each other by a layer of amorphous polymer and are held together by tie molecules through the amorphous phase [e.g. 1]. The lamellae are formed from mostly folded chains. The thickness of lamellae is determined by the parameters such as interfacial energies, glass transition temperature and melting temperature, undercooling, segmental diffusivity, etc. The thickness reported lies usually in a narrow range between 3 and 20 nm as obtained from observations in various types of microscopes or calculated from the degree of crystallinity and long period. It has been recognized that chain folding is not so regular as it was thought and molecular packing in lamellae is subject to considerable and irregularly distributed disorder depending on undercooling- regimes of crystallization. It has been demonstrated in various ways that the planar growth front will always break up into fibrous or cellular growth. Also crystallization of polymers leads to interface instability. More sophisticated treatment of the instabilities involve perturbation analyses of planar interfaces, correlating diffusion, temperature gradients along the interface, and interfacial energy with the size of the growing crystals.
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- PIMM_NMPBC_2009_GALESKI.pdf
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- Chapitres d'ouvrages scientifiques
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Documents liés
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Article dans une revue avec comité de lectureGALESKI, Stanislaw; PIÓRKOWSKA, Ewa; ROZANSKI, Artur; GALESKI, Andrzej; JURCZUK, Kinga;
REGNIER, Gilles (Elsevier, 2016)
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Shear-strain step response in linear regime of dilute suspensions of naturally bent carbon nanotubes Article dans une revue avec comité de lectureImpressive enhancements of the storage modulus have been documented when low volume fractions of single wall carbon nanotubes (SWNTs) are added to a Newtonian solvent for obtaining dilute suspensions. The intrinsic bending ...
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Article dans une revue avec comité de lectureWALCZAK, M; CIESIELSKI, W; GALESKI, A; POTRZEBOWSKI, M.J.; HILTNER, A; BAER, Eric;
REGNIER, Gilles (Wiley, 2012)
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