Simultaneous measurement of vapor diffusion and solubility coefficients in polymers by frequency response techniques

✍ Scribed by Evnochides, S. K. ;Henley, E. J.

• Publisher: Wiley (John Wiley & Sons)
• Year: 1970
• Tongue: English
• Weight: 373 KB
• Volume: 8
• Category: Article
• ISSN: 0449-2978
• DOI: 10.1002/pol.1970.160081112

✦ Synopsis

Abstract

An experimental technique for the simultaneous measurement of solubility and diffusion coefficients in polymers by frequency response techniques has been developed. A sample of polymer suspended from an electrobalance is exposed to a permeating gas whose pressure is being varied sinusoidally at ultra‐low frequencies. The phase angle and amplitude of the weight changes are measured as a function of the frequency of the pressure wave. It is shown that in the linear range the diffusivity coefficient for polyethylene–ethane calculated from the phase angle lag and the Henry's law solubility and the diffusivity obtained from the amplitude ratios are in excellent internal agreement and also agree with values obtained from transient measurements.