Measuring Dynamics
Chemical & Engineering News · 1969
People whose job it is to study the physics and chemistry of membranes will get an assist from a new development slated to become a commercial reality shortly. Called a polymer permeation analyzer (PPA), the device provides a means of measuring routinely the permeation and diffusion of a gas, liquid, or vapor through a membrane dynamically. "The key word is dynamically," points out Dr. Rafael A. Pasternak of Stanford Research Institute in Menlo Park, Calif., who played a major role in developing the unit. "PPA makes possible direct measurement of permeation and diffusion coefficients through membranes under dynamic conditions. Until now," he notes, "these parameters have been studied largely by static, closed-volume methods which have many serious limitations." PPA is an outgrowth of studies that SRI carried out for the Jet Propulsion Laboratory under NASA support. Cooperating with Dr. Pasternak on the project were Jan F. Schimscheimer (who has since returned to the Netherlands) and ...