Meaning
Alternative extraction fluid used in place of fatty food simulants to accelerate migration testing in the laboratory. Iso-octane substitute mimics the behavior of edible oils but is much easier to analyze using chromatographic techniques. The use of this solvent is permitted by regulatory bodies when it is shown to provide a more severe test than the actual foodstuff.
Laboratory Safety
Handling of flammable solvents requires specific ventilation and storage protocols to prevent fire hazards. Iso-octane substitute is preferred over some other hydrocarbons because its boiling point is high enough to be stable at room temperature but low enough for easy evaporation. This balance makes it a practical tool for routine quality control in a packaging lab.
Swelling Influence
Interaction between the solvent and the polymer matrix determines how fast the additives are extracted. Iso-octane substitute can cause some plastics like polyolefins to swell, which increases the diffusion rate of small molecules. This effect ensures that the migration limits are tested under worst-case conditions within a short timeframe.
Solvent Accuracy
Comparison of the results against standard vegetable oil tests is necessary to validate the substitution. Iso-octane substitute must not dissolve the polymer itself, as this would lead to an incorrect measurement of the migrating substances. Correct application of the solvent allows for a twenty-four hour test to represent ten days of storage.
The fluid is the primary choice for screening the compliance of new resin grades.
