ASTM D1386-15(2022)

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: D1386 − 15 (Reapproved 2022)
Standard Test Method for
Acid Number (Empirical) of Synthetic and Natural Waxes
This standard is issued under the fixed designation D1386; 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 3.1.1 acid number or acid value—the number of milligrams
of potassium hydroxide necessary to neutralize1gofthe
1.1 This test method covers the determination of the acid
sample.
number of synthetic waxes and natural waxes. The number is
obtained by direct titration of the material and indicates the
4. Significance and Use
amount of free acid present.
4.1 This test method is used to determine the property of
1.2 This test method, using an ethanol-xylene mixture, is
acid functionality. Acid functionality determines the utility of
applicable to all natural waxes, including carnauba. The test
the wax as well as being a significant Quality Control test.
method is also applicable to oxidized microcrystalline waxes,
oxidized Fischer-Tropsch, oxidized polyethylene, and montan
5. Apparatus
esters.
5.1 Analytical Balance.
1.3 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
5.2 Buret, 50 mL, with 0.1 mL graduations.
standard.
5.3 Flasks, acid value, 250 mL.
1.4 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
6. Reagents and Materials
responsibility of the user of this standard to establish appro-
6.1 Purity of Reagents—Reagent-grade chemicals or
priate safety, health, and environmental practices and deter-
equivalent, as specified in Practice E200, shall be used in all
mine the applicability of regulatory limitations prior to use.
tests.
1.5 This international standard was developed in accor-
dance with internationally recognized principles on standard-
6.2 Ethanolic Potassium Hydroxide, Standard Solution—
ization established in the Decision on Principles for the
Dissolve approximately 5.6 g of potassium hydroxide in 5.6 g
Development of International Standards, Guides and Recom-
of distilled water. Dilute with USSD3A denatured ethanol or
mendations issued by the World Trade Organization Technical
95 % ethanol to 1000 mL. Standardize with 0.1 N hydrochloric
Barriers to Trade (TBT) Committee.
acid.
6.3 Phenolphthalein Indicator Solution (10 g/litre)—
2. Referenced Document
Dissolve1gof phenolphthalein in 100 mL of USSD3A,
2.1 ASTM Standards:
denatured ethanol or 95 % ethanol.
E200 Practice for Preparation, Standardization, and Storage
6.4 Xylene.
of Standard and Reagent Solutions for ChemicalAnalysis
7. Procedure
3. Terminology
7.1 Transfer 1 g to2gofthe sample, weighed to the nearest
3.1 Definitions:
0.001 g, to a 250 mL acid-value flask. Add 40 mL of xylene.
Heat on a hot plate or water bath to put the sample into
solution. Occasional swirling may be necessary.
ThistestmethodisunderthejurisdictionofASTMCommitteeD21onPolishes
and is the direct responsibility
...