Wrap Cling Film Testing

Stretch wrap film is an extremely important packaging material used in applications from heavy duty pallet strapping to sealing food items in containers to keep them fresh. Peel cling and puncture resistance are important parameters since cling is critical in maintaining a tight wrap after an item is stretch wrapped to prevent the film from unwrapping during handling and transportation, while puncture strength is important with regards to preventing accidental puncture damage thereby helping to maintain product freshness.

Lloyd Instruments offers versatile testing of stretch wrap film with the introduction of two new test jigs for its LS1 1 kN (225 lbf) single column materials testing machine. The puncture fixture is used for testing puncture resistance of stretch wrap film according to ASTM D 5748-95 (Re-approved 2007), while the peel cling fixture is used for testing peel cling of stretch wrap film according to ASTM D 5458-95 (Re-approved 2001). In addition, the LS1 test machine can be used to perform a standard tensile test on stretch wrap film at very low force.

The versatile LS1 or LS5 test machine can also be used for tensile testing of stretch wrap film by equipping it with an EX800Plus non-contacting extensometer. The film samples have to be perfectly parallel or prepared dumbbells and are typically tested using tensile grips. The EX800Plus extensometer provides travel of 800 mm and can readily accommodate the very long elongation that occurs during tensile testing of this material.