ASTM D8301-21

Standard Test Method for Determination of the Content of Nitroxide Radical (4-Hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) in Butadiene, Styrene and Isoprene by Cyclic Voltammetry Method

SIGNIFICANCE AND USE
4.1 Nitroxide radicals (H-Tempo, O-Tempo (4-oxo-2,2,6,6-tetramethylpiperidine-1-oxyl), etc.) are widely used as inhibitors of thermopolymerization in the processes of transportation, storage, and separation of monomers (isoprene, butadiene, styrene, etc.). This test method provides a procedure for assaying nitroxide radicals in monomers.  
4.2 This procedure can be used for determination of the content of nitroxide radicals (H-Tempo, O-Tempo, etc.) in other solvents (dimethyl formamide, DMSO etc.).
SCOPE
1.1 This test method is designed to determine the content of nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo) in butadiene, isoprene, and styrene.  
1.2 This test method is applicable to samples with nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo) with concentrations to 100 mg⁄kg. The limit of detection (LOD) is 0.47 mg/kg for nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo) and the limit of quantitation (LOQ) is 1.6 mg/kg nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo).  
1.3 The following applies for the purposes of determining the conformance of the test results using this test method to applicable specifications, results shall be rounded of in accordance with the rounding-off method of Practice E29.  
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, health, and environmental practices and determine the applicability of regulatory limitations prior to use.  
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: 31-May-2021
• ICS: 83.140.01 - Rubber and plastics products in general
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.07 - Styrene, Ethylbenzene and C9 and C10 Aromatic Hydrocarbons

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: D8301 − 21
Standard Test Method for
Determination of the Content of Nitroxide Radical (4-
Hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl) in Butadiene,
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Styrene and Isoprene by Cyclic Voltammetry Method
This standard is issued under the fixed designation D8301; 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 2. Referenced Documents
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2.1 ASTM Standards:
1.1 This test method is designed to determine the content of
D1193 Specification for Reagent Water
nitroxide radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-
E29 Practice for Using Significant Digits in Test Data to
oxyl (H-Tempo) in butadiene, isoprene, and styrene.
Determine Conformance with Specifications
1.2 This test method is applicable to samples with nitroxide
2.2 Other Documents:
radical 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-
OSHARegulations, 29 CFR, paragraph 1910.1000 Air Con-
Tempo) with concentrations to 100 mg⁄kg. The limit of
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taminants
detection(LOD)is0.47mg/kgfornitroxideradical4-hydroxy-
OSHA Regulations, 29 CFR, paragraph 1910.1200 Hazard
2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo) and the limit
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Communication
of quantitation (LOQ) is 1.6 mg/kg nitroxide radical
4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl (H-Tempo).
3. Summary of Test Method
1.3 The following applies for the purposes of determining
3.1 A sample of butadiene is dissolved in acetonitrile.
the conformance of the test results using this test method to
Butadiene is separated by evaporation. The intensity of the
applicable specifications, results shall be rounded of in accor-
cathode current signal is compared in the cyclic voltammetry
dance with the rounding-off method of Practice E29.
(CV) with that produced by the known concentration of the
1.4 The values stated in SI units are to be regarded as
H-Tempo.
standard. No other units of measurement are included in this
3.2 A sample of isoprene and styrene is dissolved in
standard.
acetonitrile. The intensity of the cathode current signal is
1.5 This standard does not purport to address all of the compared in the cyclic voltammetry (CV) with that produced
by the known concentration of the H-Tempo.
safety concerns, if any, associated with its use. It is the
responsibility of the user of this standard to establish appro-
priate safety, health, and environmental practices and deter- 4. Significance and Use
mine the applicability of regulatory limitations prior to use.
4.1 Nitroxide radicals (H-Tempo, O-Tempo (4-oxo-2,2,6,6-
1.6 This international standard was developed in accor-
tetramethylpiperidine-1-oxyl), etc.) are widely used as inhibi-
dance with internationally recognized principles on standard-
tors of thermopolymerization in the processes of
ization established in the Decision on Principles for the
transportation, storage, and separation of monomers (isoprene,
Development of International Standards, Guides and Recom-
butadiene,styrene,etc.).Thistestmethodprovidesaprocedure
mendations issued by the World Trade Organization Technical
for assaying nitroxide radicals in monomers.
Barriers to Trade (TBT) Committee.
2
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
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This test method is under the jurisdiction of ASTM Committee D16 on contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
Aromatic, Industrial, Specialty and Related Chemicals and is the direct responsi- Standards volume information, refer to the standard’s Document Summary page on
bility of Subcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10Aromatic the ASTM website.
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Hydrocarbons. Available from U.S. Government Printing Office, Superintendent of
Current edition approved June 1, 2021. Published June 2021. DOI: 10.1520/ Documents, 732 N. Capitol St., NW, Washington, DC 20401-0001, http://
D8301-21. www.access.gpo.gov.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
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D8301 − 21
NOTE 1—Commercially available solutions of the same concentration
4.2 This procedure can be used for determination of the
can be used instead.
content of nitroxide radicals (H-Tempo, O-Tempo, etc.) in
other solvents (dimethyl formamide, DMSO etc.). 9.2 Preparation of Sodium Perchlorate Solution in Acetoni-
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trile (с=0.1 mol/dm NaClO ):
4
5. Interferences
9.2.1 Weigh 3.06 6 0.01 g of sodium perchlorate (NaClO )
4
5.1 T
...