Journal
POLYMER INTERNATIONAL
Volume 51, Issue 10, Pages 852-858Publisher
WILEY
DOI: 10.1002/pi.858
Keywords
poly(epsilon-caprolactone); lamellar single crystal; diffraction contrast image; chain-packing structure; enzymatic degradation behaviour
Categories
Ask authors/readers for more resources
Solution-grown lamellar single crystals of poly(epsilon-caprolactone) (PCL) were prepared from a dilute solution of n-hexanol by the isothermal crystallization condition or the self-seeding method. Hexagonal-shaped lamellar crystals with and without spiral growth were obtained, and the crystals produced well-resolved electron diffraction diagrams. The chain-packing structure and morphological complexity in lamellar crystals were investigated by bright-field and dark-field diffraction contrast methods of transmission electron microscopy. Based on both diffraction contrast images, it was revealed that both tightly and loosely chain-packing regions exist in one lamellar crystal. Thus, it was emphasized that PCL solution-grown lamellar single crystals consist of micro-crystals with nano-order size for the crystalline core region. Lipase type XIII from Pseudomonas sp was used for the enzymatic degradation of the PCL lamellar crystals. Enzymatic degradation progressed perpendicularly from the crystal lateral sides, without decrease of the molecular weight and lamellar thickness, yielding notched-shaped morphologies to the crystals. These results further indicate that PCL lamellar crystals consist of nano-order micro-crystals, and that enzyme hydrolyzes the loosely chain-packing regions between the tightly chain-packing regions (micro-crystal regions). (C) 2002 Society of Chemical Industry.
Authors
I am an author on this paper
Click your name to claim this paper and add it to your profile.
Reviews
Recommended
No Data Available