Crystallization and Dissolution of Flow-Induced Precursors
نویسندگان
چکیده
منابع مشابه
Crystallization and dissolution of flow-induced precursors.
We make use of a specially synthesized linear high density polyethylene with a bimodal molecular weight distribution (MWD) to demonstrate that it is possible to produce a suspension of extended-chain (shish) crystals only. Such a suspension can be generated at high temperatures, above but close to the equilibrium melting temperature of the unconstrained extended-chain crystals (T(m)(0)=141.2 de...
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Flow-induced crystallization is investigated through short-term shear flow experiments on poly(1butene) in the RheoDSC device. We demonstrate that the DSC signal shows contributions from spherulitic morphology in the center of the sample and oriented structures at the edge of the sample, the latter being induced by edge effects at the free surface. It is shown that, although small in terms of v...
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An experimental configuration that combines the powerful capabilities of a short-term shearing apparatus with simultaneous optical and X-ray scattering techniques is demonstrated, connecting the earliest events that occur during shear-induced crystallization of a polymer melt with the subsequent kinetics and morphology development. Oriented precursors are at the heart of the great effects that ...
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ژورنال
عنوان ژورنال: Physical Review Letters
سال: 2008
ISSN: 0031-9007,1079-7114
DOI: 10.1103/physrevlett.100.048302