Sample size effect on the effective diffusion coefficients for the gas contained in closed-cell polyethylene-based foam subjected to compressive creep tests

In this article, the effect of sample size on the degassing behavior of closed‐cell low density polyethylene (LDPE) foam under long‐term compressive static loading is presented. The creep response was modeled by assuming isothermal compression of the gas. The change in gas pressure with time was obtained and the effective diffusion coefficients were calculated from pressure decrease using an analytical solution of the diffusion equation, and were found to increase when the sample size was reduced. © 2005 Wiley Periodicals, Inc. J Appl Polym Sci, 2006