Influence of absorbed water on free-volume properties of polymers based on epoxidized vegetable oils investigated by positron annihilation

This manuscript is focused on the determination of free-volumes in vegetable oil-based photopolymer matrixes. Knowledge of the properties of microstructures of polymeric materials is important in optimizing the properties of the amperometric biosensors. Positron annihilation lifetime spectroscopy (PALS) is a spectroscopic method for microstructural analysis of polymer systems. A swelling test provides information about a crosslink density of polymer network. Combination of these methods provides information about the network properties of the polymer matrixes. The semiempirical quantum mechanical model Tao-Eldrup was used to estimate the sizes of individual free-volumes in these matrixes. The role of the free-volume and crosslink density of networks in polymer matrixes with potential use as holding matrix to improve laccase-based amperometric biosensors has been determined. (authors)