Determination of diffusion coefficient of oxygen into polymers by using electron spin resonance spectroscopy. I. Poly(methyl methacrylate)

摘要

AbstractA simple technique has been proposed for the measurement of the diffusion coefficient of oxygen into polymeric spheres. The technique is based on the scavenging of radicals produced by high energy radiation by oxygen. The diffusion coefficient of oxygen determined for poly(methyl methacrylate) has shown an inverse dependency on the dose received. Diffusion coefficient determined for low doses (D= 3.4 × 10−8cm2/s) as well as that determined after extrapolation to zero dose (D0= 3.7 × 10−8cm2/s) are in excellent agreement with the values reported in the liter