Free volume microstructure of tetramethylpolycarbonate at low temperatures studied by positron annihilation lifetime spectroscopy: a comparison with polycarbonate

The temperature dependence of the local free volume in polyethylene and polytetrafluoroethylene: A positron lifetime study

“…83 As CH 3 mobility increases there is more expansion and which is in the order of 20% (e.g., PC at room temperature). 70 In this place we point electron scattering at the end groups which decreases the electron mobility and, in accordance out that the physical relevance of the number of holes, N, estimated previously is not very clear.…”

Positron annihilation study of iodine sorption in acrylonitrile-butadiene-styrene

“…14,15 duced to a few nanoseconds. The lifetime of o-Ps depends on the overlap of the Ps wave function The success of Fujita's theory prompted us to use this to understand the transport phenomenon of with the electron wave function of the free-volume cavity.…”

Effect of thermodynamic history on secondary relaxation in glassy phenolphthalein-dimethyl-ether

“…To understand the behavior of PDE, it is noteworthy that a connection between the free volume, the thermal expansion coefficient, and the flip-flop motion of the phenyl ring has been previously reported for polycarbonate. 23 Consequently, a density dependence of the secondary process reflecting the flip-flop motion of the phenyl ring in PDE could be expected. Finally, it is worth noting that similarly to the results reported herein, the influence of thermodynamic history on the structural dynamics of glass forming systems is well documented and the faster the rate of cooling used to achieve the glassy state the faster is the structural relaxation time.…”