title: Morphology-driven surface segregation in a blend of poly(epsilon-caprolactone) and poly(vinyl chloride).
abstract: A blend of poly(epsilon-caprolactone) (PCL) and poly(vinyl chloride) (PVC) with 90 wt % PCL was prepared. Two films of this blend, which were grown at 35 and 45 degrees C, showed the absence and presence of banded spherulites, respectively. A detailed examination conducted with time-of-flight secondary ion mass spectrometry (ToF-SIMS) found that the surface composition of the film grown at 45 degrees C was related to its structure, which was shown to contain ridges and valleys. Phase images obtained using atomic force microscopy (AFM) indicated that the ridges and valleys consisted of edge-on and flat-on lamellae, respectively. ToF-SIMS imaging revealed that PVC and PCL were located mainly on the surface of the valleys and ridges, respectively. This morphology-driven surface segregation was caused by the difference in the surface energy between the flat-on and edge-on lamellae.
authors.affiliation: Department of Chemical Engineering and Materials and Characteristic Preparation Facility, Hong Kong University of Science and Technology, Clear Water Bay, Hong Kong, China.
authors.forename: Zhuo-Lin
authors.initials: ZL
authors.lastname: Cheung
authors.forename: Lu-Tao
authors.initials: LT
authors.lastname: Weng
authors.forename: Chi-Ming
authors.initials: CM
authors.lastname: Chan
authors.forename: Wei Min
authors.initials: WM
authors.lastname: Hou
authors.forename: Lin
authors.initials: L
authors.lastname: Li
mesh_terms: D018625:Microscopy, Atomic Force; D010316:Particle Size; D011091:Polyesters / Q000737:chemistry*; D011143:Polyvinyl Chloride / Q000737:chemistry*; D013499:Surface Properties
chemical_list: D011091:Polyesters; C016240:polycaprolactone; D011143:Polyvinyl Chloride