Low-rate dynamic contact angles on poly( n -butyl methacrylate) and the determination of solid surface tensions

Autor: R. Wu, C. N. C. Lam, D. Y. Kwok, A. Leung, A. W. Neumann, A. Li
Rok vydání: 1998
Předmět:
Zdroj: Colloid & Polymer Science. 276:459-469
ISSN: 1435-1536
0303-402X
DOI: 10.1007/s003960050267
Popis: Low-rate dynamic contact angles of 22 liquids on a poly(n-butyl methacrylate) (PnBMA) polymer are measured by an automated axisymmetric drop shape analysis-profile (ADSA-P). It is found that 16 liquids yielded non-constant contact angles, and/or dissolved the polymer on contact. From the experimental contact angles of the remaining 6 liquids, it is found that the liquid–vapor surface tension times cosine of the contact angle changes smoothly with the liquid–vapor surface tension, i.e. γlv cos θ depends only on γlv for a given solid surface (or solid surface tension). This contact angle pattern is in harmony with those from other inert and non-inert (polar and non-polar) surfaces [34–37, 45–47]. The solid–vapor surface tension calculated from the equation-of-state approach for solid-liquid interfacial tensions [14] is found to be 28.8 mJ/m2, with a 95% confidence limit of ±0.5 mJ/m2, from the experimental contact angles of the 6 liquids.
Databáze: OpenAIRE