Structural study on syndiotactic polystyrene: 3. Crystal structure of planar form I
1993; Elsevier BV; Volume: 34; Issue: 8 Linguagem: Inglês
10.1016/0032-3861(93)90319-6
ISSN1873-2291
AutoresYôzô Chatani, Yukio Shimane, Toshikazu Ijitsu, Toshimitsu Yukinari,
Tópico(s)biodegradable polymer synthesis and properties
ResumoThe crystal structure of a planar zigzag form of syndiotactic polystyrene (planar form I) obtained by annealing as-cast samples from solutions (molecular compounds with the solvents) was studied by X-rays. Crystal data are as follows: orthorhombic system, space group P212121 (no. 19), but finally Pbnm (no. 62), a = 8.81 Å, b = 28.82 Å, c (chain axis) = 5.06 Å, eight monomer units (four chains) per unit cell. Planar form I is different in alignment of the planar zigzag chains from planar form II obtained by melt-crystallization, which belongs to the hexagonal system. Moreover, the crystal structure of planar form I is characterized by a 'stacking fault' in the molecular packing.
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