ASTM D1938-19 PDF

Full title and description

ASTM D1938-19 — Standard Test Method for Tear-Propagation Resistance (Trouser Tear) of Plastic Film and Thin Sheeting by a Single‑Tear Method. This method describes a constant‑rate, single‑tear (trouser tear) test for ranking the tear‑propagation resistance of plastic films and thin sheeting (≤ 1 mm thick) using grip‑separation and controlled crosshead speed.

Abstract

ASTM D1938-19 defines specimen preparation, conditioning, test‑machine setup, and data interpretation for a trouser‑tear (single‑tear) test that measures the force required to propagate a tear in plastic film and thin sheeting. The method differentiates behavior for highly extensible versus slightly/non‑extensible films and provides guidance on when the technique is appropriate for specification and ranking purposes.

General information

• Status: Active
• Publication date: May 9, 2019
• Publisher: ASTM International
• ICS / categories: 83.140.10 - Films and sheets
• Edition / version: D1938‑19
• Number of pages: 5

Core bibliographic and status details from the ASTM document record.

Scope

This test method covers determination of the force necessary to propagate a tear in plastic film and thin sheeting (thickness 1 mm (0.04 in.) or less) by a single‑tear (trouser) method. The method employs a constant rate of grip separation, may use grip separation to measure specimen extension, and is not applicable to materials that fail in a brittle manner. It is intended for ranking tear‑propagation resistance of films of comparable thickness, not for direct service‑performance prediction. The method is noted to be similar to, but not technically equivalent with, ISO 6383‑1 (different specimen sizes and speeds).

Key topics and requirements

• Test type: single‑tear (trouser tear) with constant‑rate-of‑grip separation.
• Material limit: intended for plastic film and thin sheeting ≤ 1 mm (0.04 in); film commonly defined ≤ 0.25 mm (0.010 in).
• Specimen preparation and conditioning: follow specified specimen geometry, number of replicates and environmental conditioning for reproducible results.
• Data interpretation: distinguishes between highly extensible films (use initial/peak and steady‑state force behavior) and slightly/non‑extensible films (use average tear force); provides charts for load‑time/load‑displacement interpretation.
• Limitations: not applicable for brittle failures; comparisons should be made only between specimens of similar thickness and construction.
• Committee and provenance: developed by ASTM Committee D20 (Subcommittee D20.19) and published as D1938‑19 (DOI 10.1520/D1938‑19).

These key points derive from the standard text and its Significance & Use and Scope sections.

Typical use and users

Used by materials and quality laboratories, film and packaging manufacturers, converters, R&D groups, and suppliers of thin polymeric sheeting to rank tear‑propagation resistance for quality control, material comparison, and specification checks. Instrumentation suppliers and testing labs also reference the method when configuring universal testers and grips for thin film testing.

Related standards

Standards commonly referenced alongside ASTM D1938 include ISO 6383‑1 (similar trouser‑tear method but different specimen size and speeds), ASTM D1004 (Graves tear, for tear initiation at low loading rates), and other ASTM plastics/film test methods (for example tear and peel tests such as ASTM D1876 for peel of adhesives). Choice of method depends on whether the goal is tear initiation, tear propagation, or adhesive peel characterization.

Keywords

tear propagation; trouser tear; single‑tear method; plastic film; thin sheeting; tear resistance; grip separation; ASTM D1938; D20 plastics testing; film testing; specimen conditioning.

FAQ

Q: What is this standard?

A: ASTM D1938‑19 is a test method that specifies a single‑tear (trouser) test procedure for measuring tear‑propagation resistance of plastic film and thin sheeting (≤ 1 mm thick) using a constant rate of grip separation.

Q: What does it cover?

A: It covers specimen geometry and preparation, conditioning, test machine setup (constant‑rate grip separation), test execution, data collection and interpretation (including distinctions between highly extensible and non‑extensible films), and limitations where the method is inappropriate (brittle materials, dissimilar thickness comparisons).

Q: Who typically uses it?

A: Film and packaging manufacturers, converters, independent testing laboratories, R&D groups, and quality assurance teams who need to rank tear‑propagation resistance or verify material consistency.

Q: Is it current or superseded?

A: D1938‑19 is the current published edition (published May 9, 2019). It replaced earlier editions (for example D1938‑14). A routine review/revision work item for the standard was initiated in 2025, so users should confirm the ASTM record for any amendments or a newer issuance after 2019 before final acceptance for contract or specification use.

Q: Is it part of a series?

A: It is part of ASTM’s plastics testing portfolio developed under Committee D20 (Subcommittee D20.19) and appears in Book of Standards Volume 08.01 alongside other film and sheeting test methods.

Q: What are the key keywords?

A: Tear propagation, trouser tear, single‑tear, plastic film, thin sheeting, tear resistance, ASTM D1938, grip separation.