LAUSR

Abstract The release of graphene from graphene-polyethylene composite films involving 1.5 wt% graphene into various food simulants under different temperature and time conditions is studied in this paper. A simple and quick method, which only requires ultraviolet-visible spectroscopy, to quantize the total amount of released graphene is developed. Meanwhile, the morphology and size of releases into food simulants are characterized by TEM and laser particle size analysis. The results reveal that the graphene in graphene-polyethylene composite films, which are released into food simulants mostly occurs at the interface rather than “supposed” migrates from the interior of composite films. This is because graphene clusters or graphene-containing polymer flakes, which are located at the outer surface, are easily pulled off, while the size much less than the interspace between polymers is the precondition for graphene migrating from the interior. Various factors in terms of specific surface area, ethanol concentration, temperature and experiment period are investigated to show their influences on the release of graphene. Among all the case studies, the maximum amount of graphene release is found to be 1.6 mg/kg.