This volume is a eoLleetion of manuseripts based on presenta­ tions at a symposium "Polymerie Separation Media" organized for the Seeond Chemieal Congress of the North Ameriean Continent held in Las Vegas, August 24-29, 1980. The symposium was organized to bring together researehers in the expanding field of separations based on polymerie media. A diverse eross-seetion of re.seareh areas were presented, whieh were linked by the aetive separation agent being a polymerie material. I would like to thank the authors for their endeavours and the audienee for their partieipation, espeeially in light of the late change of venue for this meeting. Finally I am indebted to the Division of Polymer Chemistry Ine. of the Ameriean Chemieal Soeiety for their sponsorship. Anthony R. Cooper, Ph.D., FRSC Palo Alto, California July 1981 v CONTENTS DEDICATION TO BAREND H. J. HOFSTEE . . . . . . . . . . . .. . . 1 PART I TRANSPORT IN POLYMERIC MEDIA Some Condiserations Regarding the Hyperfi1teration of Organic Liquids. 7 I. J. Bass and P. Meares Measurement of Transport Interaction in Membranes . . . . . . . . . . . . . . 19 . . . K. S. Spiegier, T. S. Brun and A. Berg Free Vo1ume Estimates in Crysta11ine and Fi11ed Polymers . . .. .............. 21 H. L. Frisch and A. I. Kreituss Diffusion Coefficients of Po1ystyrenes in Porous Gels From Mass Transfer Dispersion in Gel Permeation Chromatography . . . . . . . . . . . . . . . . . . 27 . . . .