Electron beam irradiated polyamide-6,6 films-I: characterization by wide angle X-ray scattering and infrared spectroscopy

Electron beam irradiation of poly(iminohexamethylene-iminoadipoyl) (polyamide-6,6) (PA66) films prepared by compression molding was carried out over a range of irradiation doses (20-500 kGy) in air. The crystallinity variations were studied using infrared (IR) spectroscopy and wide angle X-ray scattering (WAXS). Gel content of the irradiated films was measured. G(S)/G(X) ratio for the irradiated films was found out from Charlesby-Pinner plot. It was seen that the reduction of crystallinity was drastic initially, which was less in the range 200-500 kGy. The 934 and 1202 cm-1 bands were used to follow the crystallinity trends in the PA66 films. The presence of both α and γ phase was seen in all the PA66 films at room temperature. The gel content was observed in the films receiving a dose of 200 and 500 kGy. No gel was found in the films below 200 kGy. The G(S)/G(X) value was found out to be ∼3.34, which suggests more of chain scission over crosslinking.