ASTM D3826-98

Designation: D 3826 – 98
Standard Practice for
Determining Degradation End Point in Degradable
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Polyethylene and Polypropylene Using a Tensile Test
This standard is issued under the fixed designation D 3826; the number immediately following the designation indicates the year of
original adoption or, in the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. A
superscript epsilon (e) indicates an editorial change since the last revision or reapproval.
1. Scope D 374 Test Methods for Thickness of Solid Electrical Insu-
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lation
1.1 This practice covers the determination of a degradation-
D 618 Practice for Conditioning Plastics and Electric Insu-
end point (a brittle point) for degradable polyethylene/
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lating Materials for Testing
polypropylene films and sheeting less than 1.0 mm (0.04 in.)
D 638M Test Method for Tensile Properties of Plastics
thick. This practice is not intended for determination of the rate
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[Metric]
of degree of degradation of a polyethylene/polypropylene film
D 882 Test Methods for Tensile Properties of Thin Plastic
or sheet, but rather, to assess when in the course of its
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Sheeting
degradation under some condition, a brittle point is reached. If
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D 883 Terminology Relating to Plastics
one wishes to monitor tensile elongation during the degrada-
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D 1435 Practice for Outdoor Weathering of Plastics
tion process (such as when the tensile elongation is signifi-
D 1922 Test Method for Propagation Tear Resistance of
cantly greater than 5 %), Test Method D 882 is recommended.
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Plastic Film and Thin Sheeting by Pendulum Method
This practice should not be considered the only way of
D 5208 Practice for Operating Fluorescent UV and Conden-
determining a degradation-end point.
sation Apparatus for Exposure of Photodegradable Plas-
1.2 Tensile properties of plastics 1.0 mm (0.04 in.) or
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tics
greater in thickness shall be determined in accordance with
E 691 Practice for Conducting an Interlaboratory Study to
Test Method D 638.
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Determine the Precision of a Test Method
1.3 Use a static weighing-constant rate of grip separation
test. This procedure employs a constant rate of separation of
3. Terminology
the grips holding the sample and a static load cell.
3.1 Definitions:
NOTE 1—This procedure is based on the use of grip separation as a
3.1.1 Definitions of terms and symbols relating to tension
measure of extension; however, the desirability of using extension
testing of plastics appear in the Annex to Test Method D 638.
indicators accurate to 61.0 % or better as specified in Test Method D 638
3.1.2 line grips, n—in tensile testing machines, grips having
is recognized, and a provision for the use of such instrumentation is
faces designed to concentrate the entire gripping force along a
incorporated in the procedure.
single line perpendicular to the direction of testing stress.
1.4 This procedure has been successful for determining the
3.1.3 tear failure, n—in tensile testing of films, a failure
degradation end point of ethylene-carbon-monoxide copoly-
characterized by fracture initiating at one edge of the specimen
mers and has screened successfully two other additive-type
and progressing across the specimen at a rate slow enough to
polyethylenes in a round robin test.
produce an anomalous load-deformation curve.
1.5 The values stated in SI units are to be regarded as the
3.2 Description of Terms Specific to This Standard:
standard. The values in parentheses are for information only.
3.2.1 film, n—for the purpose of this practice, a piece of
1.6 This standard does not purport to address all of the
material not exceeding 0.250 mm (0.01 in.) in thickness.
safety concerns, if any, associated with its use. It is the
3.2.2 brittle point, n—in degradable polyethylene/
responsibility of the user of this standard to establish appro-
polypropylene film, that point in the history of a material when
priate safety and health practices and determine the applica-
75 % of the specimens tested have a tensile elongation at break
bility of regulatory limitations prior to use.
of 5 % or less.
1.7 There is no equivalent ISO standard.
4. Significance and Use
2. Referenced Documents
4.1 The tensile elongation property determined by this
2.1 ASTM Standards:
practice is of value for the characterization of degradable
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This practice is under the jurisdiction of ASTM Committee D-20 on Plastics
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and is the direct responsibility of Subcommittee D20.96 on Environmentally Annual Book of ASTM Standards, Vol 10.01.
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Degradable Plastics. Annual Book of ASTM Standards, Vol 08.01.
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Current edition approved April 10, 1998. Published January 1999. Originally Annual Book of ASTM Standards, Vol 08.03.
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published as D 3826 – 91. Last previous edition D 3826 – 91. Annual Book of ASTM Standards, Vol 14.02.
Copyright © ASTM, 100 Barr Harbor Drive, West Conshohocken, PA 19428-2959, United States.
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D 3826
materials. The tensile
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