ASTM D2578-23

Standard Test Method for Wetting Tension of Polyethylene and Polypropylene Films

SIGNIFICANCE AND USE
5.1 When a drop of liquid rests on the surface of a solid, and a gas is in contact with both, the forces acting at the interfaces must balance. These forces can be represented by surface energies acting in the direction of the surfaces and it follows that:
   where:
  θ  =  angle of contact of the edge of the drop with the solid surface,   γGL  =  surface energy of the gas - liquid interface,   γGS  =  surface energy of the gas - solid interface, and   γSL  =  surface energy of the solid - liquid interface.    
5.1.1 The right side of the above equation (the difference between the surface energies of the gas - solid and solid - liquid interfaces) is defined as the wetting tension of the solid surface. It is not a fundamental property of the surface but depends on interaction between the solid and a particular environment.  
5.1.2 When the gas is air saturated with vapors of the liquid, γGL will be the surface tension of the liquid. If the angle of contact is 0° the liquid is said to just wet the surface of the solid, and in this particular case (since cos θ = 1) the wetting tension of the solid will be equal to the surface tension of the liquid.  
5.2 The ability of polyethylene and polypropylene films to retain inks, coatings, adhesives, etc., is primarily dependent upon the character of their surfaces, and can be improved by one of several surface-treating techniques. These same treating techniques have been found to increase the wetting tension of a polyethylene or a polypropylene film surface in contact with mixtures of formamide and ethyl Cellosolve in the presence of air. It is therefore possible to relate the wetting tension of a polyethylene or a polypropylene film surface to its ability to accept and retain inks, coatings, adhesives, etc. The measured wetting tension of a specific film surface can only be related to acceptable ink, coating, or adhesive retention through experience. Wetting tension in itself is not a completely acceptable measur...
SCOPE
1.1 This test method covers the measurement of the wetting tension of a polyethylene or polypropylene film surface in contact with drops of specific test solutions in the presence of air.  
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to inch-pound units that are provided for information only and are not considered standard.
Note 1: This test method and the specified reagents were specifically developed for polyethylene and polypropylene films. It is possible to utilize this test method and the specified reagents for films composed of other polymers, but this can affect the surface energies of the gas-liquid and solid-liquid interfaces, which will affect the contact angle and wetting tension. The applicability and significance for use of non-polyolefin materials must be established by the user.  
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 hazards statements are given in Section 9.
Note 2: This test method is equivalent to ISO 8296.  
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-Jan-2023
• ICS: 83.140.10 - Films and sheets
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.19 - Film, Sheeting, and Molded Products

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: D2578 − 23
Standard Test Method for
1
Wetting Tension of Polyethylene and Polypropylene Films
This standard is issued under the fixed designation D2578; 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.
1. Scope* E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to
1.1 This test method covers the measurement of the wetting
Determine the Precision of a Test Method
tension of a polyethylene or polypropylene film surface in
E2935 Practice for Evaluating Equivalence of Two Testing
contact with drops of specific test solutions in the presence of
Processes
air.
2.2 ISO Standard:
1.2 The values stated in SI units are to be regarded as
ISO 8296 Plastics—Film and Sheeting—Determination of
standard. The values given in parentheses are mathematical
3
Wetting Tension
conversions to inch-pound units that are provided for informa-
tion only and are not considered standard.
3. Terminology
NOTE 1—This test method and the specified reagents were specifically
3.1 Definitions:
developed for polyethylene and polypropylene films. It is possible to
3.1.1 Terms used in this standard are defined in accordance
utilize this test method and the specified reagents for films composed of
with Terminology D883, unless otherwise specified. For terms
other polymers, but this can affect the surface energies of the gas-liquid
and solid-liquid interfaces, which will affect the contact angle and wetting
relating to precision and bias and associated issues, the terms
tension. The applicability and significance for use of non-polyolefin
used in this standard are defined in accordance with Terminol-
materials must be established by the user.
ogy E456.
1.3 This standard does not purport to address all of the
3.2 Definitions of Terms Specific to This Standard:
safety concerns, if any, associated with its use. It is the
3.2.1 treated—surface characteristics of the film have been
responsibility of the user of this standard to establish appro-
modified by flame, corona discharge, or other means to
priate safety, health, and environmental practices and deter-
promote the adhesion of inks, etc.
mine the applicability of regulatory limitations prior to use.
Specific hazards statements are given in Section 9.
4. Summary of Test Method
NOTE 2—This test method is equivalent to ISO 8296.
4.1 In this test method drops of a series of mixtures of
1.4 This international standard was developed in accor- 4
formamide and ethyl Cellosolve of gradually increasing sur-
dance with internationally recognized principles on standard-
face tension are applied to the surface of the polyethylene or
ization established in the Decision on Principles for the
polypropylene film until a mixture is found that just wets the
Development of International Standards, Guides and Recom-
film surface. The wetting tension of the polyethylene or
mendations issued by the World Trade Organization Technical
polypropylene film surface will be approximated by the surface
Barriers to Trade (TBT) Committee.
tension of this particular mixture.
2. Referenced Documents
5. Significance and Use
2
2.1 ASTM Standards:
5.1 When a drop of liquid rests on the surface of a solid, and
D618 Practice for Conditioning Plastics for Testing
a gas is in contact with both, the forces acting at the interfaces
D883 Terminology Relating to Plastics
must balance. These forces can be represented by surface
energies acting in the direction of the surfaces and it follows
1
This test method is under the jurisdiction of ASTM Committee D20 on Plastics
that:
and is the direct responsibility of Subcommittee D20.19 on Film, Sheeting, and
Molded Products. γGLcosθ 5 γGS 2 γSL (1)
Current edition approved Feb. 1, 2023. Published February 2023. Originally
approved in 1967. Last previous edition approved in 2017 as D2578 - 17. DOI:
10.1520/D2578-23.
2 3
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM 4th Floor, New York, NY 10036, http://www.ansi.org.
4
Standards volume information, refer to the standard’s Document Summary page on Registered trademark of Union Carbide Corp. for ethylene glycol monoethyl
the ASTM website. ether.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C
...

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: D2578 − 17 D2578 − 23
Standard Test Method for
1
Wetting Tension of Polyethylene and Polypropylene Films
This standard is issued under the fixed designation D2578; 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.
1. Scope*
1.1 This test method covers the measurement of the wetting tension of a polyethylene or polypropylene film surface in contact
with drops of specific test solutions in the presence of air.
1.2 The values stated in SI units are to be regarded as standard. The values given in parentheses are mathematical conversions to
inch-pound units that are provided for information only and are not considered standard.
NOTE 1—This test method and the specified reagents were specifically developed for polyethylene and polypropylene films. It is possible to utilize this
test method and the specified reagents for films composed of other polymers, but this can affect the surface energies of the gas-liquid and solid-liquid
interfaces, which will affect the contact angle and wetting tension. The applicability and significance for use of non-polyolefin materials must be
established by the user.
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 hazards statements are given in Section 89.
NOTE 2—This test method is equivalent to ISO 8296.
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.
2. Referenced Documents
2
2.1 ASTM Standards:
D618 Practice for Conditioning Plastics for Testing
D883 Terminology Relating to Plastics
E456 Terminology Relating to Quality and Statistics
E691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
E2935 Practice for Evaluating Equivalence of Two Testing Processes
2.2 ISO Standard:
3
ISO 8296 Plastics—Film and Sheeting—Determination of Wetting Tension
1
This test method is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.19 on Film, Sheeting, and Molded
Products.
Current edition approved Dec. 15, 2017Feb. 1, 2023. Published January 2018February 2023. Originally approved in 1967. Last previous edition approved in 20092017
as D2578 - 09.D2578 - 17. DOI: 10.1520/D2578-17.10.1520/D2578-23.
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.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D2578 − 23
3. Terminology
3.1 Definitions:
3.1.1 Terms used in this standard are defined in accordance with Terminology D883, unless otherwise specified. For terms relating
to precision and bias and associated issues, the terms used in this standard are defined in accordance with Terminology E456.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 treated—surface characteristics of the film have been modified by flame, corona discharge, or other means to promote the
adhesion of inks, etc.
4. Summary of Test Method
4
4.1 In this test method drops of a series of mixtures of formamide and ethyl Cellosolve of gradually increasing surface tension
are applied to the surface of the polyethylene or polypropylene film until a mixture is found that just wets the film surface. The
wetting tension of the polyethylene or polypropylene film surface will be approximated by the surface tension of this particular
mixture.
5. Significance and Use
5.1 When a drop of liquid rests on the surface of a solid, and a
...