A method for the dynamic measurement of diffusivities of gases in polymers

摘要: A method is presented for determining the diffusivity of a gas in polymer from response to step concentration change continuous-flow permeation chamber. The outlined procedure has several advantages over techniques currently use: it requires simple numerical integration rather than curve fitting; utilizes complete response, portion which falls within region validity short-time asympotic solution diffusion equation; and applicable both flat membranes cylindrical tubes. An illustration provided by measurement sulfur dioxide PTFE tube at temperatures.