ASTM D8496-23

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: D8496 − 23
Standard Test Method for
Determination of Hydroquinone (HQ) Content in Vinyl
Acetate Monomer (VAM) Using Ultraviolet-Visible (UV-Vis)
1,2
Spectrophotometer
This standard is issued under the fixed designation D8496; 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 D1152 Specification for Methanol (Methyl Alcohol) (With-
drawn 2021)
1.1 This test method covers the determination of hydroqui-
E29 Practice for Using Significant Digits in Test Data to
none (HQ) in colorless vinyl acetate monomer (VAM). This
Determine Conformance with Specifications
test method is applicable to the determination of HQ in the
concentration range from 1 to 25 ppm.
3. Summary of Test Method
1.2 For purposes of determining conformance of an ob-
3.1 This test method is quick, and it is easier to measure the
served or a calculated value using this test method to relevant
amount/quantity of hydroquinone (HQ) in vinyl acetate mono-
specifications, test result(s) shall be rounded off “to the nearest
mer (VAM) quantitatively by using an ultraviolet-visible (UV-
unit” in the last right-hand digit used in expressing the
Vis) spectrophotometer following the Beer-Lambert Law
specification limit in accordance with Practice E29.
principle at absorbance of 293 nm and methanol as a blank.
1.3 For ensuring safety, hazard information and guidance,
3.2 In this process, neither color development/reaction nor
follow the manufacturer’s material safety data sheet.
special reagent/processing is required, and the VAM sample
can be analyzed directly without further processing.
1.4 The values stated in SI units are to be regarded as
standard. No other units of measurement are included in this
4. Significance and Use
standard.
4.1 VAM is an organic vinyl ester compound. This colorless
1.5 This standard does not purport to address all of the
liquid is the precursor to polyvinyl acetate, an important
safety concerns, if any, associated with its use. It is the
industrial polymer. VAM may be subject to rapid spontaneous
responsibility of the user of this standard to establish appro-
polymerization if the inhibitor is not present or becomes
priate safety, health, and environmental practices and deter-
depleted during prolonged storage.
mine the applicability of regulatory limitations prior to use.
4.2 VAM is typically shipped with a HQ inhibitor as free
1.6 This international standard was developed in accor-
radical scavenger. VAM should be evaluated to ensure that
dance with internationally recognized principles on standard-
appropriate systems (for example, temperature and inhibitor
ization established in the Decision on Principles for the
quantity) are assured during storage, transportation, and getting
Development of International Standards, Guides and Recom-
prolonged shelf life.
mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
4.3 Most VAM shipped from the manufacturer will contain
an inhibitor, typically 3 to 5 ppm HQ for regional shipments
2. Referenced Documents
and up to 25 ppm HQ for long-range shipments.
2.1 ASTM Standards:
5. Interferences
5.1 Methanol and VAM have no interference at 293 nm in a
This test method is under the jurisdiction of ASTM Committee D01 on Paint UV-Vis spectrophotometer.
and Related Coatings, Materials, and Applications and is the direct responsibility of
6. Apparatus
Subcommittee D01.35 on Solvents, Plasticizers, and Chemical Intermediates.
Current edition approved Feb. 1, 2023. Published February 2023. DOI: 10.1520/
6.1 UV-Vis Spectrophotometer, absorbance at 293 nm.
D8496-23.
Provided by the Berger Paints Bangladesh Limited, Berger House, Rd No 2,
6.2 Volumetric Flask, 50 mL and 100 mL capacity.
Uttara, Dhaka 1230, Bangladesh.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM The last approved version of this historical standard is referenced on www.ast-
Standards volume information, refer to the standard’s Document Summary page on m.org.
the ASTM website. Clark, Jim. “The Beer-Lambert: Law Chemistry,” LibreTexts.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D8496 − 23
6.3 Pipets or Auto-Pipets, 1 mL or 2 mL capacity. 10.3 Determine the absorbance of each of these standards at
293 nm using methanol as the blank with the UV-Vis spectro-
6.4 Quartz Cuvette, material: Q, path Length: 10 mm, and
photometer.
Match Code: 6.
10.4 Construct a calibration curve on rectangular coordinate
6.5 Beakers, 50 mL and 250 mL capacity.
graph paper or software of UV-Vis spectrophotometer by
plotting the absorbance of the calibration standards at 293 nm.
7. Reagents and Materials
7.1 Purity of Reagents—Reagent-grade chemicals shall be
11. Procedure
used in all tests. Unless otherwise indic
...