ASTM D3643-15

Standard Test Method for Acid Number of Certain Alkali-Soluble Resins

SIGNIFICANCE AND USE
4.1 This test method is not appropriate for alkali-soluble resins whose acid functionality is due to incorporated anhydrides. Variations in manufacture, storage, and possible contamination of anhydride functional resins may cause partial hydrolysis, or esterification, which will invalidate data from this test method. Anhydride functional resins should be characterized by Test Method D3644.  
4.2 This test method is used to measure a property of acid functionalized resins. Acid number determines the utility of resins as well as being a significant quality control measure.
SCOPE
1.1 This test method covers the measurement of the free acidity present in certain alkali-soluble resins.  
1.2 This test method is not suitable for styrene-maleic anhydride resins.  
1.3 The resin manufacturer should specify whether or not this test method may be used for his product(s).  
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
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 and health practices and determine the applicability of regulatory limitations prior to use.

General Information

• Status: Historical
• Publication Date: 31-Oct-2015
• ICS: 83.080.10 - Thermosetting materials
• Technical Committee: D21 - Polishes
• Drafting Committee: D21.02 - Raw Materials

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D3643 − 15
Standard Test Method for
1
Acid Number of Certain Alkali-Soluble Resins
This standard is issued under the fixed designation D3643; 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 4. Significance and Use
4.1 This test method is not appropriate for alkali-soluble
1.1 This test method covers the measurement of the free
resins whose acid functionality is due to incorporated anhy-
acidity present in certain alkali-soluble resins.
drides. Variations in manufacture, storage, and possible con-
1.2 This test method is not suitable for styrene-maleic
tamination of anhydride functional resins may cause partial
anhydride resins.
hydrolysis, or esterification, which will invalidate data from
1.3 The resin manufacturer should specify whether or not this test method. Anhydride functional resins should be char-
this test method may be used for his product(s). acterized by Test Method D3644.
4.2 This test method is used to measure a property of acid
1.4 The values stated in SI units are to be regarded as
functionalized resins. Acid number determines the utility of
standard. No other units of measurement are included in this
resins as well as being a significant quality control measure.
standard.
1.5 This standard does not purport to address all of the
5. Reagents and Materials
safety concerns, if any, associated with its use. It is the
5.1 Purity of Reagents—Reagent grade chemicals shall be
responsibility of the user of this standard to establish appro-
used in all tests. Unless otherwise indicated, it is intended that
priate safety and health practices and determine the applica-
all reagents shall conform to the specifications of the Commit-
bility of regulatory limitations prior to use.
tee onAnalytical Reagents of theAmerican Chemical Society,
4
where such specifications are available. Other grades may be
2. Referenced Documents
used, provided it is first ascertained that the reagent is of
2
2.1 ASTM Standards:
sufficiently high purity to permit its use without lessening the
D362 SpecificationforIndustrialGradeToluene(Withdrawn
accuracy of the determination.
3
1989)
5.2 Purity of Water—Unless otherwise indicated, references
D1152 Specification for Methanol (Methyl Alcohol)
to water shall be understood to mean reagent water conforming
D1193 Specification for Reagent Water
to Specification D1193.
D3644 Test Method for Acid Number of Styrene-Maleic
Anhydride Resins
5.3 Neutral Solvent Mixture—Mix equal parts of denatured
alcohol and industrial toluene conforming respectively to the
3. Terminology
requirements described for SDA. 3A (200 proof) and Specifi-
cation D362. Neutralize the mixture using 0.1 N KOH solution
3.1 Definitions:
and phenolphthalein indicator solution, until the faint pink
3.1.1 acid number—the number of milligrams of potassium
color persists for 1 min.
hydroxide (KOH) required to neutralize the alkali-reactive
5.4 Phenolphthalein Indicator Solution (10 g/L)—Dissolve
groups in1gof material under the conditions of test.
1.0 g of phenolphthalein in 100 mLof denatured alcohol (SDA
3A, 200 proof).
1
5.5 Potassium Hydroxide, Methyl Alcohol Solution (1
ThistestmethodisunderthejurisdictionofASTMCommitteeD21onPolishes
and is the direct responsibility of Subcommittee D21.02 on Raw Materials.
mL = 5.6 mg KOH)—Dissolve 6.6 g of potassium hydroxide
Current edition approved Nov. 1, 2015. Published November 2015. Originally
approved in 1978. Last previous edition approved in 2010 as D3643 – 10. DOI:
10.1520/D3643-15.
2 4
For referenced ASTM standards, visit the ASTM website, www.astm.org, or Reagent Chemicals, American Chemical Society Specifications, American
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM Chemical Society, Washington, DC. For suggestions on the testing of reagents not
Standards volume information, refer to the standard’s Document Summary page on listed by the American Chemical Society, see Analar Standards for Laboratory
the ASTM website. Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
3
The last approved version of this historical standard is referenced on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
www.astm.org. MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

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D3643 − 15
(KOH) in 1 L of methyl alcohol conforming to the require-
A = millilitres of alkali solution required for titration of the
ments described in Specification D1152. Standardize against
sa
...

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: D3643 − 10 D3643 − 15
Standard Test Method for
1
Acid Number of Certain Alkali-Soluble Resins
This standard is issued under the fixed designation D3643; 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 free acidity present in certain alkali-soluble resins.
1.2 This test method is not suitable for styrene-maleic anhydride resins.
1.3 The resin manufacturer should specify whether or not this test method may be used for his product(s).
1.4 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
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 and health practices and determine the applicability of regulatory
limitations prior to use.
2. Referenced Documents
2
2.1 ASTM Standards:
3
D362 Specification for Industrial Grade Toluene (Withdrawn 1989)
D1152 Specification for Methanol (Methyl Alcohol)
D1193 Specification for Reagent Water
D3644 Test Method for Acid Number of Styrene-Maleic Anhydride Resins
3. Terminology
3.1 Definitions:
3.1.1 acid number—the number of milligrams of potassium hydroxide (KOH) required to neutralize the alkali-reactive groups
in 1 g of material under the conditions of test.
1
This test method is under the jurisdiction of ASTM Committee D21 on Polishes and is the direct responsibility of Subcommittee D21.02 on Raw Materials.
Current edition approved May 1, 2010Nov. 1, 2015. Published June 2010November 2015. Originally approved in 1978. Last previous edition approved in 20042010 as
D3643 – 98D3643 – 10.(2004). DOI: 10.1520/D3643-10.10.1520/D3643-15.
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
The last approved version of this historical standard is referenced on www.astm.org.
3.1.1.1 Discussion—
If carboxylic anhydrides are present, only one half of these groups will be titrated and indicated by this test method.
4. Significance and Use
4.1 This test method is not appropriate for alkali-soluble resins whose acid functionality is due to incorporated anhydrides.
Variations in manufacture, storage, and possible contamination of anhydride functional resins may cause partial hydrolysis, or
esterification, which will invalidate data from this test method. Anhydride functional resins should be characterized by Test Method
D3644.
4.2 This test method is used to determine themeasure a property of maleic anhydride resins functionality. Maleic acid anhydride
resins functionality acid functionalized resins. Acid number determines the utility of resinresins as well as being a significant
quality control test. measure.
5. Reagents and Materials
5.1 Purity of Reagents—Reagent grade chemicals shall be used in all tests. Unless otherwise indicated, it is intended that all
reagents shall conform to the specifications of the Committee on Analytical Reagents of the American Chemical Society, where
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
1

---------------------- Page: 1 ----------------------
D3643 − 15
4
such specifications are available. Other grades may be used, provided it is first ascertained that the reagent is of sufficiently high
purity to permit its use without lessening the accuracy of the determination.
5.2 Purity of Water—Unless otherwise indicated, references to water shall be understood to mean reagent water conforming to
Specification D1193.
5.3 Neutral Solvent Mixture—Mix equal parts of denatured alcohol and industrial toluene conforming respectively to the
requirements described for SDA. 3A (200 proof) and Specification D362. Neutralize the mixture using 0.1 N KOH solution and
phenolphthalein indicator solution, until the faint pink color persists for 1 min.
5.4 Phenolphthalein Indicator Solution (10 g/L)—Dissolve 1.0 g of phenolphthalein in 100 mL of denatured alcohol (SDA 3A,
200 proof).
5.5 Potassium Hydroxide, Methyl Alcohol Solution (1 mL = 5.6 mg KOH)—Dissolve
...