Polypropylene isotactic solution-grown

Masada, I. Okihara, T. Murakami, S. Ohara, M. Kawaguchi, A. Katayama, K. (1993), A bimodal structure of solution-grown isotactic polypropylene with orthogonally crossed lamellae.. Journal of Polymer Science, Part B Polymer Physics 31, 843-52. 

Well defined lath-shaped lamellar crystals of isotactic polypropylene were grown from solution [163]. The thickness of these lamellae, as determined by small-angle X-ray diffraction of crystal aggregates, is 125 A. The crystals were mainly monolayer with the shorter and larger dimensions, respectively, of about 0.2 and 1 pm. Similar lamellar crystals were observed by Sauer et al. [164], Morrow et al. [165], Kojima [166], and Lotz and Wittmann [167]. Fibrils parallel to the longitudinal direction of the lamella were often observed. According to Kojima [166] these fibrils connect the planes of fracture and cleavage that are parallel to the a axis. This is an indication that the 010 planes are the most probable fold planes. Lotz and... 

Figure 3.10 Lath-like crystals of isotactic polypropylene grown at 110°C from a 0.01% solution in cc-chloronaphthalene. The crystal structure is monoclinic, with b (parallel to the short dimension of the lath) being the unique axis. The crystals have been decorated with polyethylene rods that indicate sectoriza-tion. Scale bar is 1 pm. From Wittmann and Lotz [9] with permission from John Wiley Sons, Inc.

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