ASTM D2115-22

Standard Practice for Oven Heat Stability of Poly(Vinyl Chloride) Compositions

SIGNIFICANCE AND USE
4.1 Poly(vinyl chloride) compositions degrade by discoloration on prolonged exposure to heat. The degree of discoloration is related to the condition of exposure, such as length of period and temperature. When the conditions of exposure are fixed and controlled, then the relative resistance to discoloration due to heat of two or more compositions is able to be determined. The precision of heat stability testing is also dependent on the thickness of the specimens and the history of heat exposure prior to testing. This practice allows for control or the reporting of these variables.  
4.2 This practice is particularly applicable for determining gross differences in the heat stabilities of poly(vinyl chloride) compositions that are detectable as a color change. It is not intended to measure absolute thermal stability. This test method applies when observed changes are evidence of degradation, molecular degradation phenomena such as chain-scission or cross-linking are not identifiable.  
4.3 While discoloration caused by exposure to elevated temperature is commonly regarded as evidence of degradation in poly (vinyl chloride) compositions, some vinyl compositions undergo substantial change in color without appreciable loss of mechanical strength, chemical resistance, etc., whereas others resist change in color yet undergo substantial change in other properties. Do not take resistance to discoloration as sole evidence of thermal stability. It is recommended that this test be supplemented by others such as tensile strength and elongation, impact strength, and deflection temperature under load (for rigid compositions), durometer hardness (for nonrigid compositions), and dilute solution viscosity. The test results before and after oven exposure are compared to determine the degree of degradation that has been produced in each of the properties measured.  
4.4 This practice is able to predict the relative discoloration in processing, provided that the compositions in quest...
SCOPE
1.1 This practice lists procedures for determining the relative thermal stability of sheet or molded poly(vinyl chloride) compounds as indicated by discoloration due to exposure to an elevated temperature at controlled oven conditions.  
1.2 A specimen preparation technique using a two-roll mill is provided for compositions that are not in molded or sheeted form.  
1.3 This practice is not intended for use in purchasing specifications because the conditions of processing plastic compounds vary widely, and the degree of correlation of data obtained by this practice to process exposure has not been determined. However, despite this limitation, this practice does yield data of value in judging the comparative service quality of poly(vinyl chloride) compositions.  
1.4 The values stated in SI units are to be regarded as the standard. The values in parentheses are given for information only.  
1.5 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.
Note 1: This standard is similar in content, but not technically equivalent to ISO 305–1990.  
1.6 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: 14-Jul-2022
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.15 - Thermoplastic Materials

Relations

• Refers: ASTM D883-24 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2024
• Refers: ASTM D883-23 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2023
• Refers: ASTM D883-20 - Standard Terminology Relating to Plastics
• Effective Date: 01-Jan-2020
• Refers: ASTM D883-19c - Standard Terminology Relating to Plastics
• Effective Date: 01-Aug-2019
• Refers: ASTM D883-19a - Standard Terminology Relating to Plastics
• Effective Date: 15-Apr-2019
• Refers: ASTM D883-19 - Standard Terminology Relating to Plastics
• Effective Date: 01-Feb-2019
• Refers: ASTM D883-18a - Standard Terminology Relating to Plastics
• Effective Date: 01-Dec-2018
• Refers: ASTM D883-18 - Standard Terminology Relating to Plastics
• Effective Date: 01-Nov-2018
• Refers: ASTM D1600-18 - Standard Terminology for Abbreviated Terms Relating to Plastics (Withdrawn 2024)
• Effective Date: 01-Jan-2018
• Refers: ASTM D883-17 - Standard Terminology Relating to Plastics
• Effective Date: 15-Aug-2017
• Refers: ASTM D1600-14 - Standard Terminology for Abbreviated Terms Relating to Plastics
• Effective Date: 01-Feb-2014
• Refers: ASTM D1600-13 - Standard Terminology for Abbreviated Terms Relating to Plastics
• Effective Date: 15-Apr-2013
• Refers: ASTM D883-12e1 - Standard Terminology Relating to Plastics
• Effective Date: 15-Nov-2012
• Refers: ASTM D883-11 - Standard Terminology Relating to Plastics
• Effective Date: 15-May-2011
• Refers: ASTM D883-08 - Standard Terminology Relating to Plastics
• Effective Date: 01-Mar-2008

Overview

ASTM D2115-22 is the Standard Practice for Oven Heat Stability of Poly(Vinyl Chloride) Compositions, published by ASTM International. This standard outlines reliable procedures for determining the relative thermal stability of sheet or molded poly(vinyl chloride) (PVC) compounds based on discoloration after controlled oven exposure. Heat stability is a critical property for PVC materials, as they can degrade and discolor with prolonged or excessive heat exposure, influencing both processing and end-use performance.

ASTM D2115-22 provides practical, reproducible methods to compare the resistance of different PVC compositions to heat-induced discoloration under fixed conditions. This practice is especially valuable for detecting gross differences in heat stability between formulations. While it does not measure absolute thermal stability, results help assess comparative service quality and suitability for various applications.

Key Topics

- Purpose:

• To determine the relative heat stability of poly(vinyl chloride) compounds through controlled oven aging and observation of discoloration.
• Test Specimens:
  • Covers both molded/sheeted materials and those prepared using a laboratory two-roll mill.
• Variables Controlled:
  • Oven temperature, exposure duration, specimen thickness, and pre-exposure history.
• Limits:
  • Not designed for purchasing specifications due to processing variability.
  • Not a direct measurement of molecular degradation (such as chain scission or cross-linking).
• Supplementary Testing Recommendation:
  • For a comprehensive assessment, discoloration results should be accompanied by mechanical (e.g., tensile strength), physical, and chemical property tests.

Applications

ASTM D2115-22 is widely used in the plastics and polymer industries, particularly for quality control and R&D settings. Key applications include:

• Evaluating Formulation Changes:
  Developers compare new or modified PVC recipes for heat stability, especially when changing additives like stabilizers or plasticizers.
• Quality Consistency:
  Manufacturers monitor batch-to-batch uniformity in heat resistance as part of routine quality assurance for PVC sheets, pipes, or profiles.
• Process Optimization:
  Data from this practice predict how PVC compounds may react to thermal stresses during typical processing (e.g., extrusion, molding).
• Material Selection:
  End-users and specifiers select the most suitable PVC compounds for products exposed to elevated temperatures during service, ensuring desired performance and longevity.

This standard is not intended as a sole basis for material acceptance but is essential for comparative testing and improvement of poly(vinyl chloride) compounds.

Related Standards

• ASTM D883: Terminology Relating to Plastics - provides definitions used within ASTM D2115-22.
• ASTM D1600: Terminology for Abbreviated Terms Relating to Plastics.
• ISO 305: Plastics-Determination of Thermal Stability of Poly(Vinyl Chloride), Related Chlorine-Containing Polymers and Copolymers and Their Compounds-Discoloration Method (similar in scope but not technically equivalent).

Following ASTM D2115-22 enhances data consistency and comparability within the PVC industry, supporting international trade, development, and regulatory compliance. Adhering to standardized methods for heat stability testing helps ensure that poly(vinyl chloride) compositions meet quality standards and perform as expected in real-world applications.

Keywords:
ASTM D2115-22, oven heat stability, poly(vinyl chloride) compositions, PVC heat stability test, thermal degradation, discoloration, plastics testing standards, PVC quality control

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: D2115 − 22
Standard Practice for
Oven Heat Stability of Poly(Vinyl Chloride) Compositions
This standard is issued under the fixed designation D2115; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope* 2. Referenced Documents
1.1 This practice lists procedures for determining the rela- 2.1 ASTM Standards:
tive thermal stability of sheet or molded poly(vinyl chloride) D883 Terminology Relating to Plastics
compounds as indicated by discoloration due to exposure to an D1600 Terminology forAbbreviatedTerms Relating to Plas-
elevated temperature at controlled oven conditions. tics
2.2 ISO Standard:
1.2 A specimen preparation technique using a two-roll mill
ISO305–1990 Plastics—Determination ofThermal Stability
is provided for compositions that are not in molded or sheeted
of Poly(Vinyl Chloride), Related Chlorine-Containing
form.
Polymers and Copolymers and Their Compounds—
1.3 This practice is not intended for use in purchasing
Discoloration Method
specifications because the conditions of processing plastic
compounds vary widely, and the degree of correlation of data 3. Terminology
obtained by this practice to process exposure has not been
3.1 General—Definitions are in accordance with Terminol-
determined. However, despite this limitation, this practice does
ogy D883 and abbreviations with Terminology D1600, unless
yield data of value in judging the comparative service quality
otherwise indicated.
of poly(vinyl chloride) compositions.
4. Significance and Use
1.4 The values stated in SI units are to be regarded as the
standard. The values in parentheses are given for information 4.1 Poly(vinyl chloride) compositions degrade by discolor-
only.
ation on prolonged exposure to heat. The degree of discolor-
ation is related to the condition of exposure, such as length of
1.5 This standard does not purport to address all of the
period and temperature. When the conditions of exposure are
safety concerns, if any, associated with its use. It is the
fixed and controlled, then the relative resistance to discolor-
responsibility of the user of this standard to establish appro-
ation due to heat of two or more compositions is able to be
priate safety, health, and environmental practices and deter-
determined. The precision of heat stability testing is also
mine the applicability of regulatory limitations prior to use.
dependent on the thickness of the specimens and the history of
NOTE 1—This standard is similar in content, but not technically
heat exposure prior to testing. This practice allows for control
equivalent to ISO 305–1990.
or the reporting of these variables.
1.6 This international standard was developed in accor-
4.2 This practice is particularly applicable for determining
dance with internationally recognized principles on standard-
gross differences in the heat stabilities of poly(vinyl chloride)
ization established in the Decision on Principles for the
compositions that are detectable as a color change. It is not
Development of International Standards, Guides and Recom-
intended to measure absolute thermal stability. This test
mendations issued by the World Trade Organization Technical
method applies when observed changes are evidence of
Barriers to Trade (TBT) Committee.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
This practice is under the jurisdiction ofASTM Committee D20 on Plastics and contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials. Standards volume information, refer to the standard’s Document Summary page on
Current edition approved July 15, 2022. Published July 2022. Originally the ASTM website.
approved in 1962. Last previous edition approved in 2017 as D2115 - 17. DOI: Available from American National Standards Institute (ANSI), 25 W. 43rd St.,
10.1520/D2115-22. 4th Floor, New York, NY 10036.
*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
D2115 − 22
degradation, molecular degradation phenomena such as chain- 5.3 Specimen Supports—The specimens shall be supported
scission or cross-linking are not identifiable. by new, clean aluminum foil placed on removable oven racks.
If an oven equipped with a rotating specimen holding device is
4.3 While discoloration caused by exposure to elevated
employed, the specimen must be supported so that there is no
temperature is commonly regarded as evidence of degradation
appreciable elongating or necking down during the test period
inpoly(vinylchloride)compositions,somevinylcompositions
that alters specimen dimensions, especially the thickness. The
undergo substantial change in color without appreciable loss of
uniformity of oven temperature shall be checked in a manner
mechanical strength, chemical resistance, etc., whereas others
similar to 5.2.5 using the specimen mounting facility provided
resist change in color yet undergo substantial change in other
by the oven rotating device.
properties. Do not take resistance to discoloration as sole
evidence of thermal stability. It is recommended that this test
6. Test Specimens
be supplemented by others such as tensile strength and
elongation, impact strength, and deflection temperature under 6.1 Test specimens shall be prepared by compounding on a
load (for rigid compositions), durometer hardness (for nonrigid
laboratory two-roll mill as follows:
compositions), and dilute solution viscosity. The test results
6.1.1 Ifthesamplehasbeenprecompounded,omit6.1.3and
before and after oven exposure are compared to determine the
6.1.4.
degree of degradation that has been produced in each of the
6.1.2 The batch size shall be such that a rolling bank 6.4 to
1 1
properties measured.
12.7 mm ( ⁄4 to ⁄2 in.) in diameter is obtained across the face
of the mill with the rolls set to give a sheet 1.02 6 0.10 mm
4.4 This practice is able to predict the relative discoloration
(0.040 6 0.004 in.) thick. If other sample thicknesses are
in processing, provided that the compositions in question are
evaluated, all comparative tests shall be made on specimens of
tested at the relative maximum temperatures developed in
the same nominal thickness.
processing.
6.1.3 Weigh all components to an accuracy of 6 1% of
4.5 This practice is not applicable to mat
...

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: D2115 − 17 D2115 − 22
Standard Practice for
Oven Heat Stability of Poly(Vinyl Chloride) Compositions
This standard is issued under the fixed designation D2115; 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.
This standard has been approved for use by agencies of the U.S. Department of Defense.
1. Scope*
1.1 This practice lists procedures for determining the relative thermal stability of sheet or molded poly(vinyl chloride) compounds
as indicated by discoloration due to exposure to an elevated temperature at controlled oven conditions.
1.2 A specimen preparation technique using a two-roll mill is provided for compositions that are not in molded or sheeted form.
1.3 This practice is not intended for use in purchasing specifications because the conditions of processing plastic compounds vary
widely, and the degree of correlation of data obtained by this practice to process exposure has not been determined. However,
despite this limitation, this practice does yield data of value in judging the comparative service quality of poly(vinyl chloride)
compositions.
1.4 The values stated in SI units are to be regarded as the standard. The values in parentheses are given for information only.
1.5 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.
NOTE 1—This standard is similar in content, but not technically equivalent to ISO 305–1990.
1.6 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
2.1 ASTM Standards:
D883 Terminology Relating to Plastics
D1600 Terminology for Abbreviated Terms Relating to Plastics
2.2 ISO Standard:
ISO305–1990 Plastics—Determination of Thermal Stability of Poly(Vinyl Chloride), Related Chlorine-Containing Polymers
and Copolymers and Their Compounds—Discoloration Method
This practice is under the jurisdiction of ASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.15 on Thermoplastic Materials.
Current edition approved Sept. 1, 2017July 15, 2022. Published September 2017July 2022. Originally approved in 1962. Last previous edition approved in 20102017 as
D2115 - 10.D2115 - 17. DOI: 10.1520/D2115-17.10.1520/D2115-22.
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.
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036.
*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
D2115 − 22
3. Terminology
3.1 General—Definitions are in accordance with Terminology D883 and abbreviations with Terminology D1600, unless otherwise
indicated.
4. Significance and Use
4.1 Poly(vinyl chloride) compositions degrade by discoloration on prolonged exposure to heat. The degree of discoloration is
related to the condition of exposure, such as length of period and temperature. When the conditions of exposure are fixed and
controlled, then the relative resistance to discoloration due to heat of two or more compositions is able to be determined. The
precision of heat stability testing is also dependent on the thickness of the specimens and the history of heat exposure prior to
testing. This practice allows for control or the reporting of these variables.
4.2 This practice is particularly applicable for determining gross differences in the heat stabilities of poly(vinyl chloride)
compositions that are detectable as a color change. It is not intended to measure absolute thermal stability. This test method applies
when observed changes are evidence of degradation, molecular degradation phenomena such as chain-scission or cross-linking are
not identifiable.
4.3 This practice is particularly applicable for determining gross differences in the heat stabilities of poly(vinyl chloride)
compositions that are detectable as a color change. It is not intended to measure absolute thermal stability. Although the observed
color changes may be evidence of degradation, molecular degradation phenomena such as chain-scission or cross-linking may not
be identifiable. While discoloration caused by exposure to elevated temperature is commonly regarded as evidence of degradation
in poly (vinyl chloride) compositions, some vinyl compositions undergo substantial change in color without appreciable loss of
mechanical strength, chemical resistance, etc., whereas others resist change in color yet undergo substantial change in other
properties. Do not take resistance to discoloration as sole evidence of thermal stability. It is recommended that this test be
supplemented by others such as tensile strength and elongation, impact strength, and deflection temperature under load (for rigid
compositions), durometer hardness (for nonrigid compositions), and dilute solution viscosity. The test results before and after oven
exposure are compared to determine the degree of degradation that has been produced in each of the properties measured.
NOTE 2—While discoloration caused by exposure to elevated temperature is commonly regarded as evidence of degradation in poly (vinyl chloride)
compositions, it must be borne in mind that some vinyl compositions may undergo substantial change in color without appreciable loss of mechanical
strength, chemical resistance, etc., whereas others may resist change in color yet undergo substantial change in other properties. Therefore, resistance to
discoloration should not be taken as sole evidence of thermal stability. It is recommended that this test be supplemented by others such as tensile strength
and elongation, impact strength, and deflection temperature under load (for rigid compositions), durometer hardness (for nonrigid compositions), and
dilute solution viscosity. The test results before and after oven exposure are compared to determine the degree of degradation that has been produced in
each of the properties measured.
4.4 This practice is able to predict the relative discoloration in processing, provided that the compositions in question are tested
at the relative maximum temperatures developed in processing.
4.5 This practice is not applicable to materials that will cross-contaminate during oven exposure.
5. Apparatus
5.1 Mill—A two-roll laboratory mill used for preparing plastic or rubber specimens from the basic ingredients or from molding
or other compounds. Provision shall be made for heating the rolls to the desired temperature and for maintaining this temperature
constant over the surfaces of both rolls within 63°C.
5.2 Oven—The oven shall be of the forced-air type and shall have the following additional requirements:
5.2.1 The oven temperature shall be controlled by an accurate, reliable thermoregulator maintaining the set point within 60.5°C
or better.
5.2.2 The oven shall be equipped with a calibrated ASTM thermometer, and the proper stem correction shall be applied to the
temperat
...