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...
Varying systematically the structure of glassy poly(amide imide), poly(ester imide), and polyimide, ...
During the last decades positron annihilation has become a very powerful tool for the investigation ...
Positron annihilation lifetime spectroscopy was used to measure the free-volume size and distributio...
The CO2 transport process was studied in a series of amine-modified epoxy resins having different cr...
The mechanism of gas diffusivity in amine modified epoxy membranes is studied in the frame of free v...
Positron lifetime measurements have been carried out in an amine-cured epoxy polymer TGDDM/DDS/BFE a...
Free volume is a topic of great discussion in the field of polymers and whilst there are a number of...
The free volume of a polymer, which corresponds to the unoccupied regions accessible to segmental mo...
The free volume changes of poly[1-(trimethyl-silyl)-1-propyne] (PTMSP) treated in supercritical CO2 ...
This article reports a study of four poly(ether imide)s with varying ethylene oxide (EO) segments le...
The glass transition phenomenon and free volume behavior below and above the glass transition temper...
The free volume in epoxy systems fully cured with aminic hardeners having different chemical structu...
The temperature dependence of mean ortho-positronium lifetime ([MATH]) and intensity (I3) was measur...
Positron annihilation spectroscopy was used to measure free-volume characteristics of selected epoxi...
The possibility of positronium induced free volume cavity expansion in some polymers above the glass...
Varying systematically the structure of glassy poly(amide imide), poly(ester imide), and polyimide, ...
During the last decades positron annihilation has become a very powerful tool for the investigation ...
Positron annihilation lifetime spectroscopy was used to measure the free-volume size and distributio...
The CO2 transport process was studied in a series of amine-modified epoxy resins having different cr...
The mechanism of gas diffusivity in amine modified epoxy membranes is studied in the frame of free v...
Positron lifetime measurements have been carried out in an amine-cured epoxy polymer TGDDM/DDS/BFE a...
Free volume is a topic of great discussion in the field of polymers and whilst there are a number of...
The free volume of a polymer, which corresponds to the unoccupied regions accessible to segmental mo...
The free volume changes of poly[1-(trimethyl-silyl)-1-propyne] (PTMSP) treated in supercritical CO2 ...
This article reports a study of four poly(ether imide)s with varying ethylene oxide (EO) segments le...
The glass transition phenomenon and free volume behavior below and above the glass transition temper...
The free volume in epoxy systems fully cured with aminic hardeners having different chemical structu...
The temperature dependence of mean ortho-positronium lifetime ([MATH]) and intensity (I3) was measur...
Positron annihilation spectroscopy was used to measure free-volume characteristics of selected epoxi...
The possibility of positronium induced free volume cavity expansion in some polymers above the glass...
Varying systematically the structure of glassy poly(amide imide), poly(ester imide), and polyimide, ...
During the last decades positron annihilation has become a very powerful tool for the investigation ...
Positron annihilation lifetime spectroscopy was used to measure the free-volume size and distributio...