Surface properties of the poly(vinyl alcohol) (PVA) blend films composed of conventional PVA and PVA having an n-alkylthio end group of 4-18 carbon atoms (Rn-PVA; n=4-18) were studied by contact angle measurements and XPS analysis. In the blend films, Rn-PVA distributed preferentially on the air side surface (but not on the opposite side) depending on the chain length of n-alkylthio end groups. The critical surface tensions, 7c, and surface-free energies, 7s, of the R12-PVA/PVA-HCA blend were the lowest of all Rn-PVA/PVA-HCA blends. The polar component of the surface free energy, ),~, of the blends with Rn-PVA of n=8-16 was substantially zero, from which these film surfaces were deduced to be predominantly covered with n-alkyl chains. The C/O ratio, the ratio of the carbon atoms to the oxygen atoms in the surface layer estimated by XPS analysis, had some correlation with 7c and Vs. However, it was suggested that the surface properties were affected not only by the composition of the surface but also by the arrangement of the n-alkyl chains on the surface.
Посилання на статтю:
Surface properties of films containing poly(vinyl alcohol) having an n-alkylthio group at one end / Toshiaki Sato*, Toshinori Tsugaru, Junnosuke Yamauchi and Takuji Okaya // Polymer. – 1993. – Vol 34. – P. 2659-2664.