ASTM D4662-20

Standard Test Methods for Polyurethane Raw Materials: Determination of Acid and Alkalinity Numbers of Polyols

SIGNIFICANCE AND USE
5.1 These test methods are suitable for quality control, as specification tests, and for research. The acid and alkalinity numbers indicate the extent of a reaction with acids. The results are measures of batch-to-batch uniformity and are typically used as correction factors in calculating hydroxyl number.
SCOPE
1.1 These test methods measure the acidic and basic constituents in polyols and other materials of high acidity or alkalinity that are soluble in mixtures of toluene and ethyl alcohol. These test methods do not apply to polyethers. (See Note 1.)  
1.2 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: There is no known ISO equivalent to this standard.  
1.3 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: 30-Jun-2020
• ICS: 83.040.30 - Auxiliary materials and additives for plastics
• ICS: 83.080.20 - Thermoplastic materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.22 - Cellular Materials - Plastics and Elastomers

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: D4662 − 20
Standard Test Methods for
Polyurethane Raw Materials: Determination of Acid and
1
Alkalinity Numbers of Polyols
This standard is issued under the fixed designation D4662; 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* issues,thetermsusedinthisstandardaredefinedinaccordance
with Terminology E456.
1.1 These test methods measure the acidic and basic con-
stituents in polyols and other materials of high acidity or 3.2 Definitions of Terms Specific to This Standard:
alkalinity that are soluble in mixtures of toluene and ethyl 3.2.1 acid number, n—the quantity of base, expressed in
alcohol. These test methods do not apply to polyethers. (See milligrams of potassium hydroxide, that is required to titrate
Note 1.) acidic constituents present in1gof sample.
1.2 This standard does not purport to address all of the 3.2.2 alkalinity number, n—the quantity of base, expressed
safety concerns, if any, associated with its use. It is the asmilligramsofpotassiumhydroxide,presentin1gofsample.
responsibility of the user of this standard to establish appro-
4. Summary of Test Method
priate safety, health, and environmental practices and deter-
mine the applicability of regulatory limitations prior to use.
4.1 The sample is dissolved in a mixture of toluene and
ethyl alcohol. The resulting single-phase solution is titrated at
NOTE 1—There is no known ISO equivalent to this standard.
room temperature with alcoholic potassium hydroxide
1.3 This international standard was developed in accor-
solution, to the end point indicated by the color change of
dance with internationally recognized principles on standard-
added phenolphthalein. Alkalinity numbers are determined by
ization established in the Decision on Principles for the
back-titration after adding excess hydrochloric acid. The end-
Development of International Standards, Guides and Recom-
point of these titrations also can be determined potentiometri-
mendations issued by the World Trade Organization Technical
cally.
Barriers to Trade (TBT) Committee.
5. Significance and Use
2. Referenced Documents
5.1 These test methods are suitable for quality control, as
2
2.1 ASTM Standards:
specification tests, and for research. The acid and alkalinity
D883 Terminology Relating to Plastics
numbersindicatetheextentofareactionwithacids.Theresults
D1193 Specification for Reagent Water
are measures of batch-to-batch uniformity and are typically
E456 Terminology Relating to Quality and Statistics
used as correction factors in calculating hydroxyl number.
E2935 Practice for Conducting Equivalence Testing in
Laboratory Applications
6. Reagents and Materials
6.1 Purity of Reagents—Use reagent-grade chemicals in all
3. Terminology
tests. Unless otherwise indicated, it is intended that all reagents
3.1 Definitions—Terms used in this standard are defined in
conform to the specifications of the Committee on Analytical
accordance with Terminology D883, unless otherwise speci-
Reagents of the American Chemical Society where such
fied. For terms relating to precision and bias and associated 3
specifications are available. Other grades are allowed, pro-
vided it is first ascertained that the reagent is of sufficiently
high purity to permit its use without lessening the accuracy of
1
These test methods are under the jurisdiction of ASTM Committee D20 on
the determination.
Plastics and are the direct responsibility of Subcommittee D20.22 on Cellular
Materials - Plastics and Elastomers.
Current edition approved July 1, 2020. Published July 2020. Originally approved
3
in 1987. Last previous edition approved in 2015 as D4662 - 15. DOI: 10.1520/ Reagent Chemicals, American Chemical Society Specifications, American
D4662-20. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or listed by the American Chemical Society, see Analar Standards for Laboratory
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Standards volume information, refer to the standard’s Document Summary page on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
the ASTM website. MD.
*A Summary of Changes section appears at the end of this standard
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohock
...

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: D4662 − 15 D4662 − 20
Standard Test Methods for
Polyurethane Raw Materials: Determination of Acid and
1
Alkalinity Numbers of Polyols
This standard is issued under the fixed designation D4662; 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 These test methods measure the acidic and basic constituents in polyols and other materials of high acidity or alkalinity that
are soluble in mixtures of toluene and ethyl alcohol. These test methods do not apply to polyethers. (See Note 1.)
1.2 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 safety, health, and healthenvironmental practices and determine the
applicability of regulatory limitations prior to use.
NOTE 1—There is no known ISO equivalent to this standard.
NOTE 1—There is no known ISO equivalent to this standard.
1.3 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:
D883 Terminology Relating to Plastics
D1193 Specification for Reagent Water
E456 Terminology Relating to Quality and Statistics
E2935 Practice for Conducting Equivalence Testing in Laboratory Applications
3. Terminology
3.1 Definitions—For definitions of terms used in these test methods see 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 acid number—number, n—the quantity of base, expressed in milligrams of potassium hydroxide, that is required to titrate
acidic constituents present in 1 g of sample.
3.2.2 alkalinity number—number, n—the quantity of base, expressed as milligrams of potassium hydroxide, present in 1 g of
sample.
4. Summary of Test Method
4.1 The sample is dissolved in a mixture of toluene and ethyl alcohol. The resulting single-phase solution is titrated at room
temperature with alcoholic potassium hydroxide solution, to the end point indicated by the color change of added phenolphthalein.
Alkalinity numbers are determined by back-titration after adding excess hydrochloric acid. The endpoint of these titrations also
can be determined potentiometrically.
1
These test methods are under the jurisdiction of ASTM Committee D20 on Plastics and are the direct responsibility of Subcommittee D20.22 on Cellular Materials -
Plastics and Elastomers.
Current edition approved Sept. 1, 2015July 1, 2020. Published September 2015July 2020. Originally approved in 1987. Last previous edition approved in 20112015 as
ε1
D4662 - 08D4662 - 15.(2011) . DOI: 10.1520/D4662-15.10.1520/D4662-20.
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.
*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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D4662 − 20
5. Significance and Use
5.1 These test methods are suitable for quality control, as specification tests, and for research. The acid and alkalinity numbers
indicate the extent of a reaction with acids. The results are measures of batch-to-batch uniformity and are typically used as
correction factors in calculating hydroxyl number.
6. Reagents and Materials
6.1 Purity of Reagents—Use reagent-grade chemicals in all tests. Unless otherwise indicated, it is intended that all reagents
conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society where such
3
specifications are available. Other grades are allowed, provided it is first ascertained that the reagent is of sufficiently high purity
...