Premium
Irradiation effects in poly(ethylene oxide)/silica nanocomposite films and gels
Author(s) -
Jurkin Tanja,
Pucić Irina
Publication year - 2013
Publication title -
polymer engineering and science
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.503
H-Index - 111
eISSN - 1548-2634
pISSN - 0032-3888
DOI - 10.1002/pen.23611
Subject(s) - crystallinity , nanocomposite , materials science , crystallization , irradiation , fourier transform infrared spectroscopy , chemical engineering , nucleation , amorphous solid , nanoparticle , ethylene oxide , oxide , composite material , polymer , polymer chemistry , nanotechnology , organic chemistry , chemistry , copolymer , physics , nuclear physics , engineering , metallurgy
Poly(ethylene oxide)/silica (PEO/SiO 2 ) nanocomposite films were modified, and nanocomposite gels were prepared by γ ‐irradiation up to 100 kGy. Thermal analysis, optical microscopy, X‐ray diffraction, and Fourier transform infrared spectroscopy revealed that the outcome mostly depended on the state of the PEO matrix on irradiation and that the state of the sample had a bearing on the effect of nanosilica addition. In unirradiated films, nanosilica induced heterogenous nucleation and increased crystallization temperatures proportional to its content. On irradiation of nanocomposite films, degradation prevailed, resulting in an increased crystallinity of samples irradiated to 50 kGy and a significant deterioration of mechanical properties at higher doses. In films irradiated in air, nanosilica did not provide radiation resistance. It enhanced oxidative degradation by increasing the content of a more radiation sensitive amorphous phase and probably facilitated the crystallization of broken chains resulting in an additional crystallinity increase. In the same dose range, the irradiation of PEO/nano‐SiO 2 aqueous solutions produced cross‐linked nanocomposite gels of much lower crystallinity and phase transformation temperatures and better mechanical properties. Interactions and radiation‐induced effects in nanosilica likely contributed to a further crystallinity reduction in nanocomposite gels. Pronounced changes on the addition of 20 wt% of nano‐SiO 2 to both nanocomposite films and gels indicate a possible synergism of γ‐irradiation and nanoparticle addition. POLYM. ENG. SCI., 53:2318–2327, 2013. © 2013 Society of Plastics Engineers