Lamellar crystals of poly(ethylene oxide) grown in toluene solutions were investigated by atomic force microscopy (AFM). Typical lamellae had a square habit with a thickness of 12.5 nm and an edge length in the range of0.01-0.2 mm depending on the crystallization time. On some lamellae large screw dislocations were observed which showed a growth face at the diagonal. When the crystals were exposed to air, the lamellae gradually disintegrated. AFM images of disintegrated regions showed that polymer chains were contracted in bundles which formed tree-like patterns. Diagonal features observed on both dislocation terraces and disintegrated lamellae support the existence of fold domains separated by the diagonals and the chain folding mechanism proposed by Kovacs.
Посилання на статтю:
Atomic force microscopy of polymer crystals: 1. Chain fold domains in poly(ethylene oxide) lamellae / D. Sn6tivy and G. J. Vancso* // Polymer. – 1992. – Vol 33. – P. 432-433.