ISO 6383-2:1983

Overview

ISO 6383-2:1983 - Plastics - Film and sheeting - Determination of tear resistance - Part 2: Elmendorf method - specifies an Elmendorf pendulum test for measuring the force required to propagate a tear from a defined starter cut in flexible plastic films and sheets. The standard defines specimen types, machine requirements, conditioning, test procedure, result calculation and reporting, and includes annexes on equipment setup, maintenance and calibration.

Key topics and technical requirements

• Test principle: an Elmendorf pendulum tears a pre-cut specimen; the pendulum energy loss is converted to a tear force (reported in newtons) and expressed with specimen thickness.
• Specimens: two common shapes - constant-radius and rectangular; starter slit nominally 20 ± 0.15 mm; groups of specimens may be tested simultaneously for very weak films. Typical sample size: five specimens or five groups per direction.
• Apparatus: Elmendorf pendulum with fixed and movable jaws, accurate scale/indicator (calibrated to 1% or better), knife for consistent starter slit, optional additional weights to increase tearing force. Jaw spacing is specified (about 2.8 ± 0.3 mm).
• Dimensions and limits: tear length set (about 43 ± 0.5 mm); maximum specimen thickness depends on machine capability; very extensible films or rigid plastics may give poor reproducibility and may be unsuitable.
• Conditioning and thickness: specimens conditioned and tested in the ISO normal atmosphere (23/50) per ISO 291 unless otherwise specified; thickness measured per ISO 4591 or ISO 4593.
• Results and reporting: calculate individual and mean tear resistance (newtons), include thickness, specimen type, conditioning atmosphere, number of specimens/groups, individual results and standard deviation, and any procedural deviations. Reject results where tear path deviates beyond specified limits.

Applications and who uses it

• Quality control and production testing for plastic film manufacturers (PVC, polyolefins and similar flexible films).
• Incoming inspection and acceptance/rejection testing for converters and packaging manufacturers.
• Materials R&D when comparing tear resistance of film formulations or processing conditions.
• Independent test laboratories and standards compliance teams specifying mechanical properties in procurement documents. Note: for highly extensible films (very elastic) or rigid plastics (thick films, polyamides, polyesters) the Elmendorf method may give poor reproducibility - other methods may be preferable.

Related standards

• ISO 6383-1 - Plastics - Film and sheeting - Determination of tear resistance - Part 1: trouser test (related method)
• ISO 291 - Plastics - Standard atmospheres for conditioning and testing
• ISO 4591 / ISO 4593 - Plastics - Film and sheeting - Methods for measuring thickness

Keywords: ISO 6383-2, Elmendorf method, tear resistance test, plastics film testing, film and sheeting, tear test, Elmendorf pendulum, ISO 291, ISO 4591.