Dependence of alpha particle track diameter on the free volume holes size using positron annihilation lifetime technique

Characterization, optical, and nanoscale free volume properties of Na‐CMC/PAM/CNT nanocomposites

“…Therefore, the increase in τ 3 or V h is assigned the thermal expansion of free volume. The behavior of τ 3 or V h with temperature is in accordance with other polymers . In the low‐temperature region, T < 130°C, the increase of V h is dominated by molecular vibrations and local motions.…”

“…The behavior of τ 3 or V h with temperature is in accordance with other polymers. 33,54 In the low-temperature region, T < 130 C, the increase of V h is dominated by molecular vibrations and local motions. At the onset temperature (130.54 ± 0.82), V h changes its slope and it is assigned the glass transition temperature T g of the Na-CMC/PAM blend.…”

“…It controls most of the physiochemical properties of polymers such as mechanical, thermal, and electrical properties . The free volume depends on loading nano‐sized fillers, blending of polymers, and heating . The interaction between positrons and the polymeric materials may result in the direct annihilation of positrons with electrons (the source of τ 2 ) or forming positronium (Ps) atom .…”

“…29 The free volume depends on loading nanosized fillers, blending of polymers, and heating. 33 The interaction between positrons and the polymeric materials may result in the direct annihilation of positrons with electrons (the source of τ 2 ) or forming positronium (Ps) atom. 34 Ps exists in two states, para-positronium (p-Ps), which consists of an electron-positron state with antiparallel spins; and ortho-positronium (o-Ps), in which the spins of the two particles are parallel.…”