Small-angle neutron scattering study on irradiated kappa carrageenan

✍ Scribed by Lucille Abad; Satoshi Okabe; Satoshi Koizumi; Mitsuhiro Shibayama

• Publisher: Elsevier Science
• Year: 2006
• Tongue: English
• Weight: 837 KB
• Volume: 381
• Category: Article
• ISSN: 0921-4526
• DOI: 10.1016/j.physb.2005.12.267

✦ Synopsis

The structure of gamma-ray-irradiated k-carrageenan in aqueous solutions was investigated in terms of small-angle neutron scattering. The scattered intensity, I(q), of non-irradiated k-carrageenan solutions (5 wt%) was well described with an Ornstein-Zernike (OZ)-type function with the correlation length of 85 A ˚, indicating that the k-carrageenan solution behaves just as a polymer solution in the semidilute regime. By increasing the irradiation dose (100 kGy), I(q) changed to a power-law function with the scattering exponent of À1.84. Further increase in dose results in a recovery of OZ-type function. This indicates that a progressive cleavage of k-carrageenan chains takes place randomly, leading to a self-similar structure at 100 kGy. This is followed by further segmentation of k-carrageenan chains.