Effect of ambient‐temperature and high‐temperature electron‐beam radiation on the structural, thermal, mechanical, and dynamic mechanical properties of injection‐molded polyamide‐6,6

Abstract

Electron-beam irradiation of injection-molded specimens of polyiminohexamethyleneiminoadipoyl (better known as polyamide-6,6) was carried out in air at ambient temperature (303 K) and a high temperature (393 K). Most of the irradiated specimens were tensile dumbbells, although a few were cylinders for compressive stress relaxation testing. A few representative samples were dipped in triallyl cyanurate (TAC) solution before ambient-temperature irradiation. The gel content of the specimens increased with radiation dose and the temperature of irradiation. Moreover, the TAC-treated specimens showed an increase in gel content over the neat specimens irradiated at the same dose levels. Wide-angle X-ray scattering and differential scanning calorimetry studies revealed that the crystallinity decreased with increasing radiation dose. Irradiation at the high temperature and treatment with TAC further decreased the crystallinity compared to irradiation at ambient temperature. As determined from compressive stress relaxation and mechanical and dynamic mechanical properties, the optimized radiation dose for ambient-temperature radiation was 200 kGy. The gels had a stiffening effect, and the rate of relaxation decreased significantly. The water-uptake characteristics of the tensile specimens were investigated; this revealed a decrease in the water absorption tendency with increasing gel content.

Radiation processing of Nylon 6 by e-beam for improved properties and performance

“…Gel content was determined by the method of solvent extraction as followed by Sengupta et al (2006) where Nylon 6 were extracted from a weighed sample by dipping into 85% formic acid at room temperature for 3 days. Gels were collected by filtering through a fritted glass crucible and weighed followed by determining their percentages in the respective samples.…”

Effect of Beta Low Irradiation Doses on the Micromechanical Properties of Surface Layer of LDPE

“…The indentation hardness H IT was calculated as maximum load to the projected area of the hardness impression according to [3][4][5][6][7]:…”

“…Where h 1 is the indentation depth at time t 1 of reaching the test force (which is kept constant), h 2 is the indentation depth at time t 2 of holding the constant test force [5][6].…”

Electron Beam Irradiation of Nylon 66: Characterization by IR Spectroscopy and Viscosity Studies

“…Radiation crosslinking of nylon has been reported by various researchers, where in most of the cases extruded films, yarns or fibers have been used [4][5][6][7]. In our earlier studies we have carried out detailed investigation on high energy radiation processing on injection moulded nylon 6 and nylon 66 specimens [8][9].…”