Polyethylene crystal habits

To help the reader unfamiliar with polyethylene single crystal habits, Fig. 10 summarizes the most typical types [32] (a) the rhombic lozenge, normally observed in PE solution crystallized at lower temperatures (b) the... 

Fig. 10 Four common types of crystal habit in polyethylene and long alkanes (a) rhombic lozenge bounded by 110 facets (b) lozenge truncated by curved 100 faces (Toda s type B) (c) leaf-shaped crystal bounded solely by curved 100 faces (step propagation rate v equals h = Gno/sin(

Olley RH, Mitchell GR, Moghaddam Y (2014) On row-structures in sheared polypropylene and a propylene-ethylene copolymer. Eur Polym J 53 37 9 Organ SJ, Keller A (1985) Solution Crystallisation of Polyethylene at high temperature Part 1 lateral crystal habits. J Mater. Sci. 20(5) 1571-1585 Perret R, Skoulios A (1972a) Study of crystallization of block copolymers having sequence poly (epsilon-caprolactone)-poly(oxyethylene). 1. Copolymers with sequences of very different lengths. Makromolekulare Chemie 162 147... 

Keith HD, Padden FJ, Lotz B, Wittmann JC. Asymmetries of habit in polyethylene crystals grown from the melt. Macromolecules 1989 22 2230-2238. 

All the lamellae so far described share the common feature of exhibiting well-defined crystal habits, even those in which growth faces are curved. In systems such as linear polyethylene, which... 

Figure 7 Polyethylene orthorhombic crystal habit, (a) Orthogonal view (b) view along the c axis.

Abstract The morphology of polyethylene has been an important theme in polymer science for more than 50 years. This review provides an historical background and presents the important findings on five specialised topics the crystal thickness, the nature of the fold surface, the lateral habit of the crystals, how the spherulite develops from the crystal lamellae, and multi-component crystallisation and segregation of low molar mass and branched species. 

Fig. 15 Lateral habit of solution- and melt-grown polyethylene single crystals. The drawing are based on electron micrographs of Organ and Keller [64]—grown from solution—and of Toda [107]—grown from the melt...

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