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Updated: Mar 27, 2026

A Simple and Efficient Protocol for the Catalytic Insertion Polymerization of Functional Norbornenes
Published on: February 27, 2017
Free volumes and gas transport in polymers: amine-modified epoxy resins as a case study
Pushkar N Patil1, David Roilo, Roberto S Brusa
1Department of Physics, University of Trento, via Sommarive 14, I-38123 Povo, TN, Italy. riccardo.checchetto@unitn.it.
Abstract:
The CO2 transport process was studied in a series of amine-modified epoxy resins having different cross-linking densities but the same chemical environment for the penetrant molecules. Positron Annihilation Lifetime Spectroscopy (PALS) was used to monitor the free volume structure of the samples and experimentally evaluate their fractional free volume fh(T) and its temperature evolution. The analysis of the free volume hole size distribution showed that all the holes have a size large enough to accommodate the penetrant molecules at temperatures T above the glass transition temperature Tg. The measured gas diffusion constants at T > Tg have been reproduced in the framework of the free volume theory of diffusion using a novel procedure based on the use of fh(T) as an input experimental parameter.
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