X-ray irradiation-induced changes in cellulose triacetate

• Published in: Radiation effects and defects in solids Vol. 167; no. 4; pp. 229 - 237
• Main Authors: Nouh, S. A., Bahareth, Radiyah A.
• Format: Journal Article
• Language: English
• Published: Abingdon Taylor & Francis 01.04.2012; Taylor & Francis Ltd
• Subjects: Cellulose; Cellulose triacetate; color changes; Colors (materials); Crosslinking; Irradiation; Molecular weight; Radiation; Refractive index; Refractivity; Viscosity; X-ray irradiation; X-rays
• ISSN: 1042-0150; 1029-4953
• DOI: 10.1080/10420150.2011.638632

Samples from sheets of the polymeric material cellulose triacetate (CTA) have been exposed to X-ray radiation in the dose range 50-260 kGy. The modifications induced in the molecular and optical properties of CTA samples due to X-ray irradiation have been studied through different characterization techniques such as intrinsic viscosity, refractive index and color change studies. The results indicated that the cross-linking is the dominant mechanism at the dose range 100-260 kGy. This cross-linking led to an increase in the value of intrinsic viscosity from 1.28 for the non-irradiated sample to 1.41 for the sample irradiated with 260 kGy at 35°C, indicating an increase in the average molecular mass. This was associated with an increase in the refractive index. Additionally, the non-irradiated CTA samples showed significant color sensitivity toward X-ray irradiation. This sensitivity appeared by the change in the blue color component of the non-irradiated CTA film to yellow after exposure to X-ray up to 260 kGy. This is accompanied by a net increase in the darkness of the samples.