Free volume of some polymeric materials in liquid-expanded monolayer at the air-water interface

Bidimensional mixtures of polymethylmethacrylate(PMMA), poly-1-trimethylsilyl-1-propyne(PTMSP) and poly-1-methyl-2-propylacetylene(PMPA) with palmitic acid(PA) were studied in monolayer, in order to compare between molecular areas showed on π-A isotherms and free volume of each polymer. Increasing degree of negative area deviation from ideality for each polymer/PA mixture monolayers were shown in the order of PMMA<PMPA<PTMSP. This result was consistent with the order of gas permeability of these polymer reported.1,2