ASTM D2121-23

Standard Test Methods for Polymer Content of Styrene Monomer

SIGNIFICANCE AND USE
5.1 This test method can be used for determining polymer concentrations in styrene monomer.  
5.2 This test method will not detect dimers and trimers.  
5.3 This test method can be used for plant control and for specification analysis.
SCOPE
1.1 These test methods cover the determination of the polymer content of styrene monomer. It should be noted, however, that dimers and trimers are not measured by these test methods.  
1.2 Test Method A, which is based on the use of a spectrophotometer or photometer, is intended for the quantitative determination of the polymer content of styrene monomer in concentrations up to 15 mg/kg. Samples containing more than 15 mg/kg of polymer must be suitably diluted before measurement. The limit of detection (LOD) is 1.2 mg/kg and the limit of quantitation (LOQ) is 4.0 mg/kg. LOD and LOQ were calculated using the last sample in Table 1.  
1.3 Test Method B is a rapid visual procedure that is intended for the approximate evaluation of polymer to a maximum concentration of 1.0 mass %. Samples having a polymer content of 1.0 mass % or greater should be suitably diluted prior to measurement.  
1.4 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off in accordance with the rounding-off method of Practice E29.  
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.  
1.6 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. For specific hazard statements, see Section 9.  
1.7 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-Oct-2023
• ICS: 71.080.15 - Aromatic hydrocarbons
• Technical Committee: D16 - Aromatic, Industrial, Specialty and Related Chemicals
• Drafting Committee: D16.07 - Styrene, Ethylbenzene and C9 and C10 Aromatic Hydrocarbons

Relations

• Replaces: ASTM D2121-16 - Standard Test Methods for Polymer Content of Styrene Monomer
• Effective Date: 01-Nov-2023
• Referred By: ASTM D2827-19 - Standard Specification for Styrene Monomer
• Effective Date: 01-Nov-2023
• Referred By: ASTM D4790-23 - Standard Terminology of Aromatic Hydrocarbons and Related Chemicals
• Effective Date: 01-Nov-2023

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: D2121 − 23
Standard Test Methods for
1
Polymer Content of Styrene Monomer
This standard is issued under the fixed designation D2121; 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* mendations issued by the World Trade Organization Technical
Barriers to Trade (TBT) Committee.
1.1 These test methods cover the determination of the
polymer content of styrene monomer. It should be noted,
2. Referenced Documents
however, that dimers and trimers are not measured by these test
2
methods.
2.1 ASTM Standards:
D2827 Specification for Styrene Monomer
1.2 Test Method A, which is based on the use of a spectro-
D3437 Practice for Sampling and Handling Liquid Cyclic
photometer or photometer, is intended for the quantitative
Products
determination of the polymer content of styrene monomer in
D4790 Terminology of Aromatic Hydrocarbons and Related
concentrations up to 15 mg/kg. Samples containing more than
Chemicals
15 mg/kg of polymer must be suitably diluted before measure-
D6809 Guide for Quality Control and Quality Assurance
ment. The limit of detection (LOD) is 1.2 mg/kg and the limit
Procedures for Aromatic Hydrocarbons and Related Ma-
of quantitation (LOQ) is 4.0 mg/kg. LOD and LOQ were
terials
calculated using the last sample in Table 1.
E29 Practice for Using Significant Digits in Test Data to
1.3 Test Method B is a rapid visual procedure that is
Determine Conformance with Specifications
intended for the approximate evaluation of polymer to a
E691 Practice for Conducting an Interlaboratory Study to
maximum concentration of 1.0 mass %. Samples having a
Determine the Precision of a Test Method
polymer content of 1.0 mass % or greater should be suitably
2.2 Other Document:
diluted prior to measurement.
OSHA Regulations, 29CFR paragraphs 1910.1000 and
3
1.4 In determining the conformance of the test results using
1910.1200
this method to applicable specifications, results shall be
rounded off in accordance with the rounding-off method of
3. Terminology
Practice E29.
3.1 See Terminology D4790 for definition of terms used in
1.5 The values stated in SI units are to be regarded as
this test method.
standard. No other units of measurement are included in this
standard.
TEST METHOD A—DETERMINATION OF POLYMER
IN STYRENE MONOMER SPECTROSCOPIC
1.6 This standard does not purport to address all of the
METHOD
safety concerns, if any, associated with its use. It is the
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
4.1 This test method utilizes the fact that polymers present
use. For specific hazard statements, see Section 9.
in the monomers are insoluble in methanol. The polymer
1.7 This international standard was developed in accor-
content of styrene monomer is determined by measurement of
dance with internationally recognized principles on standard-
the degree of turbidity produced by the addition of dry
ization established in the Decision on Principles for the
methanol to the styrene sample.
Development of International Standards, Guides and Recom-
1 2
These test methods are under the jurisdiction of ASTM Committee D16 on For referenced ASTM standards, visit the ASTM website, www.astm.org, or
Aromatic, Industrial, Specialty and Related Chemicals and are the direct responsi- contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
bility of Subcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10 Aromatic Standards volume information, refer to the standard’s Document Summary page on
Hydrocarbons. the ASTM website.
3
Current edition approved Nov. 1, 2023. Published November 2023. Originally Available from U.S. Government Printing Office Superintendent of Documents,
approved in 1962. Last previous edition approved in 2016 as D2121 – 16. DOI: 732 N. Capitol St., NW, Mail Stop: SDE, Washington, DC 20401, http://
10.1520/D2121-23. www.access.gpo.gov.
*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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D2121 − 23
TABLE 1 Styrene (mg/kg)
8.4.1 Prepare polystyrene as follows: wash 50 mL of styrene
Repeatability Reproducibility monomer twice with equal volumes of 1 N NaOH solution and
A
Aver
...

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: D2121 − 16 D2121 − 23
Standard Test Methods for
1
Polymer Content of Styrene Monomer
This standard is issued under the fixed designation D2121; 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 cover the determination of the polymer content of styrene monomer. It should be noted, however, that
dimers and trimers are not measured by these test methods.
1.2 Test Method A, which is based on the use of a spectrophotometer or photometer, is intended for the quantitative determination
of the polymer content of styrene monomer in concentrations up to 15 mg/kg. Samples containing more than 15 mg/kg of polymer
must be suitably diluted before measurement. The limit of detection (LOD) is 1.2 mg/kg and the limit of quantitation (LOQ) is
4.0 mg/kg. LOD and LOQ were calculated using the last sample in Table 1.
1.3 Test Method B is a rapid visual procedure that is intended for the approximate evaluation of polymer to a maximum
concentration of 1.0 mass %. Samples having a polymer content of 1.0 mass % or greater should be suitably diluted prior to
measurement.
1.4 In determining the conformance of the test results using this method to applicable specifications, results shall be rounded off
in accordance with the rounding-off method of Practice E29.
1.5 The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.
1.6 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 healthsafety, health, and environmental practices and determine
the applicability of regulatory limitations prior to use. use. For specific hazard statements, see Section 9.
1.7 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:
D2827 Specification for Styrene Monomer
D3437 Practice for Sampling and Handling Liquid Cyclic Products
D4790 Terminology of Aromatic Hydrocarbons and Related Chemicals
D6809 Guide for Quality Control and Quality Assurance Procedures for Aromatic Hydrocarbons and Related Materials
1
These test methods are under the jurisdiction of ASTM Committee D16 on Aromatic Hydrocarbons Aromatic, Industrial, Specialty and Related Chemicals and are the
direct responsibility of Subcommittee D16.07 on Styrene, Ethylbenzene and C9 and C10 Aromatic Hydrocarbons.
Current edition approved June 1, 2016Nov. 1, 2023. Published July 2016November 2023. Originally approved in 1962. Last previous edition approved in 20152016 as
D2121 – 15.D2121 – 16. DOI: 10.1520/D2121-16.10.1520/D2121-23.
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

---------------------- Page: 1 ----------------------
D2121 − 23
TABLE 1 Styrene (mg/kg)
A
Repeatability Reproducibility
Average
Material Limit Limit
¯
r R
X
Sample 1 — 0.4 mg/kg 1.673 1.796 2.827
Sample 2 — 2 mg/kg 2.413 1.711 3.792
Sample 3 — 4 mg/kg 3.759 4.268 5.090
Sample 4 — 10 mg/kg 10.143 3.254 9.037
TABLE 1 Styrene (mg/kg)
A Repeatability Reproducibility
Average
Material Limit Limit
¯
r R
X
Sample 1 — 2 mg/kg 2.6 0.3 0.7
Sample 2 — 5 mg/kg 4.1 0.7 1.3
Sample 3 — 6 mg/kg 7.7 1.1 3.4
A
The average of the laboratories’ calculated averages.
TABLE 2 % Recovery
Average
A
Average
Material Recovery
(mg/kg)
(%)
Sample 1 — 0.4 mg/kg 1.673 418.2
Sample 2 — 2 mg/kg 2.413 120.6
Sample 3 — 4 mg/kg 3.759 94.0
Sample 4 — 10 mg/kg 10.143 101.4
A
The average of the laboratories’ calculated averages.
E29 Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications
E691 Practice for Conducting an In
...