Structural effects on metal ion migration across polymer inclusion membranes: Dependence of membrane properties and transport profiles on the weight and volume fractions of the components

► The membrane system CTA/TBEP/D2EHPA for In(III) transport is characterized through the examination of functional and structural properties. ► Quantitative expressions denoting the relationships between most of these properties and the weight or volume fractions of the components are obtained. ► A progressive transition in the extractant percolation threshold value dependent on membrane composition is observed. ► A correlation between transport and membrane structure is established. ► Different types of transport mechanisms previously identified in PIMs are satisfactorily integrated in a single transport scheme.