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

Abstract

ABSTRACT:The influence of iodine on the free volume of acrylonitrile-butadiene-styrene (ABS) was investigated by positron annihilation lifetime spectroscopy (PALS). The results indicate the filling of free-volume holes, formation of a positronium-iodine compound (PsI 2 /PsI), and possible charge-transfer complexes (CTCs) in the initial stages and the swelling of iodine in the final stages of sorption. The present study also revealed that iodine acts as a chemical quencher of o-Ps. The average size of the free volume suggests that I 0 3 is the predominant species that fills up the free-volume holes during iodination. The diffusion process in the present case shows non-Fickian behavior and deviates from Fujita's free-volume concept as far as the fractional free volume and diffusion coefficient are concerned.

Molecular iodine/polymer complexes

“…Ramani et al [322] and Ramani and Ranganathaiah [323] investigated the iodine sorption by ABS resin, employing positron annihilation lifetime spectroscopy (PALS). Iodine sorption was performed by soaking the sample in an aqueous I 2 /KI solution for different time inter vals at room temperature.…”

Degradation of acrylonitrile-butadiene-styrene and polycarbonate by UV irradiation

“…This shows that the free radicals produced by UV irradiation inhibit Ps formation leading to the observed decrease in I 3 . If Ps formation is inhibited, it is normally seen as a decrease in o-Ps intensity as observed in earlier studies [26,36]. However, this seems to have little eect on the free volume content as evident from the slight decrease in F V during the early stages of UV exposure [ Fig.…”

“…Due to pick-o process, the o-Ps lifetime gets reduced to a few ns. The Ps localizes mainly in the free volume holes of the polymer and as such, the o-Ps lifetime is related to the mean size of the free volume holes [25,26].…”

Effect of styrene–acrylonitrile content on 0.5 M NaI/0.05 M I2 liquid electrolyte encapsulation for dye-sensitized solar cells

“…Styrene-based polymers can be developed further into QSSCs with low packing density due to the existence of rigid spacers that keep the polymer chains apart [2]. Consequently, a space is created by phenyl distortion for electrolyte containment.…”

“…GPEs are able to encapsulate liquid electrolytes thus, prevent problems such as leakage, evaporation of solvents, high temperature instability, flammability, and possible desorption [1]. Ramani et al [2] claimed that copolymers of styrene have leverage in hydrolytic stability, and the introduction of a dopant can modify charge storage. This improves charge carrier mobility.…”