Seal properties of medical packaging materials at elevated temperature

This paper proposes a novel measurement method for investigating the high-temperature peel properties of medical packaging materials. Samples were attached to a temperature-controlled aluminium block fitted to a tensile testing machine allowing the temperature dependence of peel strength to be investigated. The mechanical performance of the seals at elevated temperatures is critical. Medical packaging materials are subjected to a range of elevated temperature conditions during the materials lifetime. High-temperature peel strength is an important parameter during pouch manufacture, sterilisation and also in shipping/storage. The proposed method allows the temperature dependence of seal behaviour to be investigated by adapting standard tensile testing equipment. The technique was used to determine the peel strengths of two grades of wax/polymer-type adhesive coated (Tyvek (R)) at elevated temperatures. The peel strength was found to decline with a 50% reduction in peel strength observed between ambient and 43 degrees C. This demonstrates the importance of quantifying the effect of temperature on mechanical behaviour.