S. Meille, D. Ferro, S. Brueckner
Apr 1, 1994
Citations
4
Influential Citations
268
Citations
Quality indicators
Journal
Macromolecules
Abstract
The structure of β-isotactic polypropylene (β-iPP) has been investigated taking into consideration X-ray and electron-diffraction data supplemented by packing energy calculations. The structure is characterized by extensive disorder, and two structural models can be envisaged: both are based on domains of helices all of the same chirality, arranged on a pseudohexagonal lattice. The simplest satisfactory model is trigonal (P3 1 21 and the enantiomorphic P3 3 21) with a= b = 11.09 A and c= 6.49 A. Three monomers form the asymmetric unit, and six chains, each with a 0.5 occupancy factor, coexist in the unit cell