| abstract |
In forming containers by distending preforms of nitrile thermoplastic material at molding temperature, the improvement comprising exposing such preforms to low dosage radiation to reduce residual nitrile monomer in the thermoplastic material and then distending the irradiated preforms to cause HCN generated during irradiation to flash off in forming the container. The containers formed have unusually low concentrations of residual nitrile monomer as well as extractable HCN making them especially suitable for packaging foods, beverages, pharmaceuticals and the like. The irradiated preforms from which such containers are made have similarly low residual nitrile monomer levels. |