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Structural Studies on Syndiotactic 1,2-Poly(1,3-butadiene) by X-Ray Measurements and Molecular Mechanics Calculations

✍ Scribed by Roberto Napolitano; Beniamino Pirozzi; Simona Esposito

Publisher
John Wiley and Sons
Year
2006
Tongue
English
Weight
267 KB
Volume
207
Category
Article
ISSN
1022-1352

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✦ Synopsis

Abstract

Summary: Two samples of syndiotactic l,2‐poly(1,3‐butadiene) with different constitutional and configurational regularities were characterized by DSC analysis and X‐ray powder diffraction. Possible models of the crystal structure were obtained by molecular mechanics calculations performed with various sets of potential functions. X‐ray powder profiles calculated for these models were in good agreement with experiments. The agreement between simulated and experimental X‐ray powder profiles was improved by taking into account, in the calculated models, the presence of configurational defects. This indicates that configurational defects can be included in the crystal phase.

Projection along the b axis of a portion of the crystal structure of sPBD12 containing a [mm] triad in the energy minimum.

magnified imageProjection along the b axis of a portion of the crystal structure of sPBD12 containing a [mm] triad in the energy minimum.

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