ASTM F904-22

Standard Practice for Separation of Plies for Bond Strength of Laminated Flexible Materials

SIGNIFICANCE AND USE
5.1 Laminates are made by bonding together two or more layers of material or materials, where each layer might be a single or multi-layer material. When the bonding agent is reactive and requires time to reach full performance, the bond strength is typically measured as a green (un-cured) bond and a cured bond. For processes that intentionally create a nonlaminated edge, that edge is generally used to initiate the bond strength measurement. The techniques described in this practice can be used to initiate separation of plies when a non-laminated edge is not present.
SCOPE
1.1 This practice describes techniques for separating plies of laminates made from flexible materials such as cellulose, paper, plastic film, and foil to enable the measurement of the bond strength or ply adhesion of the laminate. This includes laminates made by various processes: adhesive laminates, extrusion coatings, extrusion laminates, and coextrusions.  
1.2 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information purposes only.  
1.3 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use. Specific precautionary statements are given in 6.1.1.  
1.4 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.

General Information

• Status: Published
• Publication Date: 31-May-2022
• ICS: 83.140.20 - Laminated sheets
• Technical Committee: F02 - Primary Barrier Packaging
• Drafting Committee: F02.20 - Physical Properties

Standards Content (Sample)

This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the
Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
Designation: F904 − 22
Standard Practice for
Separation of Plies for Bond Strength of Laminated Flexible
1
Materials
ThisstandardisissuedunderthefixeddesignationF904;thenumberimmediatelyfollowingthedesignationindicatestheyearoforiginal
adoption or, in the case of revision, the year of last revision.Anumber in parentheses indicates the year of last reapproval.Asuperscript
epsilon (´) indicates an editorial change since the last revision or reapproval.
1. Scope 3. Terminology
1.1 Thispracticedescribestechniquesforseparatingpliesof 3.1 Definitions:
laminates made from flexible materials such as cellulose, 3.1.1 bond strength—amount of force or energy required to
paper, plastic film, and foil to enable the measurement of the separatepliesofmaterialormaterialsplustheforcetobendthe
bond strength or ply adhesion of the laminate. This includes plies.
laminates made by various processes: adhesive laminates,
4. Summary of Practice
extrusion coatings, extrusion laminates, and coextrusions.
4.1 This practice describes three general techniques that can
1.2 The values stated in SI units are to be regarded as the
be used to initiate separation of any two plies to facilitate a
standard. The values given in parentheses are provided for
bondstrengthmeasurement.Threetechniquesaredescribedfor
information purposes only.
use with samples that do not have a non-laminated edge.
1.3 This standard does not purport to address all of the
TechniqueAdescribes various forms of mechanical separation.
safety concerns, if any, associated with its use. It is the
Techniques B and C involve the use of heat or solvents to
responsibility of the user of this standard to establish appro-
separate the plies.The separated plies of the test specimen may
priate safety, health, and environmental practices and deter-
be placed into the grips of a tensile testing machine to
mine the applicability of regulatory limitations prior to use.
determine the force (or energy) required to further separate the
Specific precautionary statements are given in 6.1.1.
plies, which is defined as bond strength.
1.4 This international standard was developed in accor-
5. Significance and Use
dance with internationally recognized principles on standard-
ization established in the Decision on Principles for the
5.1 Laminates are made by bonding together two or more
Development of International Standards, Guides and Recom-
layers of material or materials, where each layer might be a
mendations issued by the World Trade Organization Technical
single or multi-layer material. When the bonding agent is
Barriers to Trade (TBT) Committee.
reactive and requires time to reach full performance, the bond
strength is typically measured as a green (un-cured) bond and
2. Referenced Documents
a cured bond. For processes that intentionally create a non-
2
2.1 ASTM Standards:
laminated edge, that edge is generally used to initiate the bond
F88 Test Method for Seal Strength of Flexible Barrier
strength measurement. The techniques described in this prac-
Materials
tice can be used to initiate separation of plies when a
E171 Practice for Conditioning and Testing Flexible Barrier
non-laminated edge is not present.
Packaging
6. Reagents and Materials
6.1 Solvents—Toluene, ethyl acetate, MEK (2-Butanone)
THF (tetrahydrofuran), or water, or other suitable solvent to
weaken the bond between layers sufficiently so that ply
separation may be started.
1
This practice is under the jurisdiction of ASTM Committee F02 on Primary
6.1.1 Warning—Use of these solvents requires that appro-
Barrier Packaging and is the direct responsibility of Subcommittee F02.20 on
priate safeguards be used to avoid hazards of skin contact,
Physical Properties.
inhalation, and flammability.
CurrenteditionapprovedJune1,2022.PublishedJuly2022.Originallyapproved
in1984.Lastpreviouseditionapprovedin2016asF904 – 16.DOI:10.1520/F0904-
7. Sampling and Test Specimens
22.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
7.1 Depending on the nature of the sample being evaluated,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
thesizeofthesample,andthereasonforevaluation,separating
Standards volume information, refer to the standard’s Document Summary page on
theASTM website. the plies in more than one location may be warranted.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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F904 − 22
8. Conditioning performed. Sample size and width may vary depending on the
sample being tested and should be noted in a report.
8.1 Conditioning of samples is not normally ne
...

This document is not an ASTM standard and is intended only to provide the user of an ASTM standard an indication of what changes have been made to the previous version. Because
it may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current version
of the standard as published by ASTM is to be considered the official document.
Designation: F904 − 16 F904 − 22
Standard Test Method Practice for
ComparisonSeparation of Plies for Bond Strength or Ply
Adhesion of Similar Laminates Made from of Laminated
1
Flexible Materials
This standard is issued under the fixed designation F904; 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 (´) indicates an editorial change since the last revision or reapproval.
INTRODUCTION
It has been widely discussed in the literature that bond strength of flexible multi-ply materials is
impossible to measure with current technology. The above is recognized and accepted, since all known
methods of measurement include the force required to bend the separated layers, in addition to that
required to separate them. However, useful information can be obtained when one realizes that the
bending force is included and that direct comparisons between different materials, or even between the
same materials of different thicknesses, cannot be made. Also, conditioning that affects the softness or
moduli of the plies will be reflected in the bond strength measurement.
1. Scope
1.1 This test method covers a procedure for comparing the bond strength or ply adhesion of similar laminates made from flexible
materials such as cellulose, paper, plastic film, and foil. This includes laminates made by various processes: adhesive laminates,
extrusion coatings, extrusion laminates, and coextrusion.
1.2 Because of the impact of the bending force, direct comparisons between different materials or even between the same materials
of different thickness cannot be made.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are provided for information
purposes only.
1.4 This standard does not purport to address all of the safety problems, if any, associated with its use. It is the responsibility
of the user of this standard to establish appropriate safety and health practices and determine the applicability of regulatory
limitations prior to use. Specific precautionary statements are given in 7.1.1.
2. Referenced Documents
2
2.1 ASTM Standards:
D882 Test Method for Tensile Properties of Thin Plastic Sheeting
3
D1898 Practice for Sampling of Plastics (Withdrawn 1998)
1
This test method practice is under the jurisdiction of ASTM Committee F02 on FlexiblePrimary Barrier Packaging and is the direct responsibility of Subcommittee F02.20
on Physical Properties.
Current edition approved April 1, 2016June 1, 2022. Published June 2016July 2022. Originally approved in 1984. Last previous edition approved in 20082016 as F904 – 98
(2008).F904 – 16. DOI: 10.1520/F0904-16.10.1520/F0904-22.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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F904 − 22
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
3. Terminology
3.1 Definitions:
3.1.1 adhesive failure—failure at the interface of two adjacent layers.
3.1.2 cohesive failure—failure within one of the two adjacent layers comprising the bonded area under test.
3.1.3 bond strength—amount of force or energy required to separate plies of material or materials plus the force to bend the plies.
3.1.4 necking—localized reduction in cross section which may occur in a material under tensile stress.
3.1.5 web—refers to roll stock after it has been unwound from the roll.
4. Summary of Test Method
4.1 Ply separation is initially started mechanically by the application of heat or by using a solvent. The separated plies of the test
specimen are placed into the grips of a tensile testing machine. The grips are then separated and the force required to further
separate the plies is defined as bond strength. Alternatively, the energy may be used.
NOTE 1—The force to bend the separated plies is included.
5. Significance and Use
5.1 Laminates are made by bonding together two or more layers of material or materials. Their performance is often dependent
on the ability of the laminate to function as a single unit. If the plies have not been properly bonded together, th
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