ABSTRACT:The solubility and diffusivity of ethylene in semicrystalline polyethylene were experimentally measured using a magnetic suspension microbalance. The sorption measurements were carried out at temperatures up to 80°C and pressures up to 66 atm. The experimentally measured solubilities were found to decrease with increasing temperature and increased with ethylene pressure in good agreement with the predictions of the Sanchez-Lacombe latticefluid model. The diffusivity of ethylene in semicrystalline polyethylene films was estimated from the reduced sorption curves using the half-time method. The experimentally determined diffusivities were compared with theoretical values predicted by a new molecular hybrid model, which combines the characteristic features of the Pace-Datyner diffusion model with those of the Kulkarni-Stern free-volume model. The ethylene diffusion coefficient was found to increase with temperature and/or the ethylene-sorbed concentration.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.