Modification induced by alpha particle irradiationin Makrofol polycarbonate

Abstract

Makrofol DE 1-1 CC polycarbonate samples were exposed to alpha particles of initial energies at levels between 5.1 and 34 MeV. The modifications induced in polycarbonate samples due to the alpha particle irradiation have been studied through different characterization techniques such as X-ray diffraction (XRD), infrared spectroscopy, intrinsic viscosity, and color difference studies. The infrared spectroscopy indicated that the intensities of the characteristic absorption bands decrease with increasing the deposited alpha energy in the range 5.1-8.4 MeV, indicating that the degradation is the dominant mechanism at this range. At the same time, an increase in the À ÀOH groups was observed at the same energy range 5.1-8.4 MeV due to the degradation of carbonate group and the À ÀH abstraction from the polymer backbone to form hydroxyl groups. The degradation reported by IR spectroscopy enhanced the degree of ordering in the degraded samples as revealed by XRD technique. Additionally, this degradation decreases the intrinsic viscosity from 0.56 to 0.43 at 358C, indicating a decrease in the average molecular mass. The non irradiated Polycarbonate polymer is nearly colorless. It showed significant darkness sensitivity towards alpha particle irradiation, indicated by an increase in the color intercept L* from 33.6 to 36.7.

Dielectric relaxation and alternating current conductivity of polyvinylidene fluoride doped with lanthanum chloride

“…It was previously reported that the crosslinking formation within the polymeric materials reduces the degree of crystallinity for some polymers. [20][21][22][23] Similar results were observed for PVDF and iodine filled samples due to the interactions between the polymer and the iodine. 24 B. Dielectric relaxation As seen, e 0 of all samples decreases with increasing the field frequency due to decreasing number of dipoles which contribute to polarization.…”

Synthesis of boron and rare earth stabilized graphene doped polyvinylidene fluoride (PVDF) nanocomposite piezoelectric materials

“…However, the ions of rare earth metals formed compound of crosslink with fluorine groups when rare earth metal was doped to PVDF polymer. This case points out that the crystal structure degraded and transformed to amorphous structure . According to our samples, cerium doping was more amorphous than erbium doping.…”

“…, the crystallinity of the samples decreases with addition of REEs such as Ce and Er. The REEs tend to form complexes with fluorocarbon groups of PVDF by way of weak secondary bonding interaction and this lead to a transition from crystalline phase to amorphous in PVDF structure . However, the ions of rare earth metals formed compound of crosslink with fluorine groups when rare earth metal was doped to PVDF polymer.…”

X-ray irradiation-induced changes in Bayfol DPF 5023 polycarbonate

“…The intrinsic viscosity shows a decrease until a minimum value around the 200 Gy irradiated sample, followed by an increase on increasing the X-ray dose up to 2300 Gy. The dose range in which the intrinsic viscosity decreases can be explained by the formation of shorter molecules as a result of degradation, which causes both a random breaking of bonds and the formation of stable molecules with a lower molecular weight (25). However, the increase in intrinsic viscosity in the dose range 200-2300 Gy indicates an increase in the molecular mass of the polymer due to the crosslinking.…”