Predicting water diffusivity in elastomers

By the use of water absorption data (rate and equilibrium), the diffusivity of distilled and salt water through Neoprene, styrene‐butadiene, and ethylene‐propylene‐diene elastomers was predicted. Activation parameters were calculated from the Arrhenius plots and were used to calculate heats of solution (all negative). Solubility coefficients ( S ) were calculated from permeability ( P ) and diffusion ( D ) coefficients. For all materials salt water showed a lower D than distilled water but a higher S and P .