The control of surface segregation of blend films using stereocomplex formation between enantiomeric polylactide chains

• Published in: Surface and interface analysis Vol. 43; no. 1-2; pp. 385 - 388
• Main Authors: Lee, Won-Ki, Wells, David D., Goacher, Robyn E., Gardella Jr, Joseph A.
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01.01.2011; Wiley
• Subjects: Atomic, molecular, and ion beam impact and interactions with surfaces; Blends; Complexation; Composition; defects and impurities; Concentration (composition); Condensed matter: electronic structure, electrical, magnetic, and optical properties; Condensed matter: structure, mechanical and thermal properties; Control surfaces; Electron and ion emission by liquids and solids; impact phenomena; Exact sciences and technology; Fluorine; fluorine-end-capped poly(lactide); Impact phenomena (including electron spectra and sputtering); Physics; Reagents; Segregations; Solid surfaces and solid-solid interfaces; stereocomplex; Surface structure; surface structures; Surfaces and interfaces; thin films and whiskers (structure and nonelectronic properties); TOF-SIMS; Polymer blends; Fluorine; Surface segregation; surface structures; Polymer films; Time-of-flight method; stereocomplex; Ion beams; Surface structure; fluorine-end-capped poly(lactide); SIMS; TOF-SIMS; Surface energy
• ISSN: 0142-2421; 1096-9918; 1096-9918
• DOI: 10.1002/sia.3487

This study investigated the stereocomplex‐induced surface structure of enantiomeric poly(lactide) (PLA) blend films by time‐of‐flight secondary ion mass spectrometry (TOF‐SIMS). The design of the blend systems was based on the principle of surface segregation of a modified component with a low surface energy, fluorine‐end‐capped PLLA (F‐PLLA). Analysis of F‐PLLA/PDLA and F‐PLLA/PLLA blends, yielded a difference in the ion beam‐induced behavior between fluorine and lactide groups. In addition, a completely phase‐separated sample of PLLA with the fluorine end‐capping agent cast onto the surface was used for a real analysis of peak intensities from the two components, simulating bulk compositions. The two blend systems, uncomplexed (F‐PLLA/PLLA) and complexed (F‐PLLA/PDLA) blends, showed quite different surface structures: namely, a higher fluorine concentration was observed in the uncomplexed blends while the complexed blends showed a wider range of fluorine concentrations, depending on the degree of complexation. This indicates that the complexed blends offer a greater level of control over the surface fluorine concentration because this concentration changes more significantly with the blend composition (or the degree of complexation). Copyright © 2010 John Wiley & Sons, Ltd.