ASTM D6099-08

This document is not anASTM standard and is intended only to provide the user of anASTM 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:D6099–03 Designation:D6099–08
Standard Test Method for
Polyurethane Raw Materials: Determination of Acidity in
1
Moderate to High Acidity Aromatic Isocyanates
This standard is issued under the fixed designation D 6099; 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 determines the acidity, expressed as parts per million (ppm) of HCl, in aromatic isocyanate samples of
greater than 100–ppm acidity. The test method is applicable to products derived from toluene diisocyanate and methylene-bis-
(4–phenylisocyanate) (see Note 1).
NOTE 1—This test method is equivalent to ISO 14898, Test Method A.
2. Referenced Documents
2
2.1 ASTM Standards:
D 883 Terminology Relating to Plastics
E 180 Practice for Determining the Precision ofASTM Methods forAnalysis andTesting of Industrial and Specialty Chemicals
E 691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 ISO Standards:
3
ISO 14898 Plastics—Aromatic isocyanates for use in the production of polyurethane—Determination of acidity
3. Terminology
3.1 Definitions— Terms used in this test method are in accordance with Terminology D 883.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 acidity, n—the acid strength of a sample expressed in ppm hydrochloric acid.
4. Summary of Test Method
4.1 The isocyanate is mixed with an excess of methanol and a cosolvent. Additional acid is released into the solvent system
during urethane formation. The acid then is titrated potentiometrically with methanolic KOH, and the acidity present in the
isocyanate sample is calculated from the titer.
5. Significance and Use
5.1 This test method can be used for research or for quality control to characterize aromatic isocyanates and prepolymers of
moderate to high acidity. Acidity correlates with performance in some polyurethane systems.
6. Apparatus
6.1 250-mL Beakers.
6.2 50-mL Pipet or Repipet, Class A volumetric.
6.3 100-mL Pipet or Repipet, Class A volumetric.
6.4 Automatic Titration Equipment , such as: , capable of inflection detection and stirring the sample while, titrating, such as:
6.4.1 Titroprocessor, and Commerically-available Automatic Titration Apparatus,
6
6.4.2 Dosimat , with magnetic stirrer.
6.4.3Reference Electrode, with saturated LiCl/ethanol solution in both chambers.
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.22 on Cellular Materials— - Plastics
and Elastomers.
Current edition approved March 10, 2003.Nov. 15, 2008. PublishedApril 2003.November 2008. Originally approved in 1997. Last previous edition approved in 19972003
as D6099-97.D 6099 - 03.
2
Annual Book of ASTM Standards, Vol. 08.01.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Annual Book of ASTM Standards, Vol. 15.05.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
*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 ----------------------
D6099–08
6.4.4
6.4.3 pH Glass Electrode, (see Note 2).
NOTE 2—A combination pH electrode with internal reference also may be used.
6.5 Magnetic Stirrer.
6.6 Stir Bars.
6.7 Watch Glasses.
6.8 Analytical Balance, capable of weighing to the nearest 1 mg.
7. Reagents and Materials
7.1 0.02 N KOH in Methanol—1.32 g KOH pellets (85 % KOH)/1000 mL methanol, standardized with potassium hydrogen
phthalate (KHP).
7.2 Toluene or 1,2,4–Trichlorobenzene (TCB), dried for 24 h over molecular sieves.
7.3 Anhydrous Methanol.
8. Sampling
8.1Since organic isocyanates react with atmospheric moisture, take special precautions in sampling. (Warning —Organic
isocyanates are toxic when they are absorbed through the skin or when the vapors are breathed.) (Warning—Provide adequate
ventilation and wear protective gloves and eyeglasses.) Usual sampling methods, for example, sampling with an open drum thief,
e
...

This document is not anASTM standard and is intended only to provide the user of anASTM 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:D6099–03 Designation:D6099–08
Standard Test Method for
Polyurethane Raw Materials: Determination of Acidity in
1
Moderate to High Acidity Aromatic Isocyanates
This standard is issued under the fixed designation D 6099; 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 determines the acidity, expressed as parts per million (ppm) of HCl, in aromatic isocyanate samples of
greater than 100–ppm acidity. The test method is applicable to products derived from toluene diisocyanate and methylene-bis-
(4–phenylisocyanate) (see Note 1).
NOTE 1—This test method is equivalent to ISO 14898, Test Method A.
2. Referenced Documents
2
2.1 ASTM Standards:
D 883 Terminology Relating to Plastics
E 180 Practice for Determining the Precision ofASTM Methods forAnalysis andTesting of Industrial and Specialty Chemicals
E 691 Practice for Conducting an Interlaboratory Study to Determine the Precision of a Test Method
2.2 ISO Standards:
3
ISO 14898 Plastics—Aromatic isocyanates for use in the production of polyurethane—Determination of acidity
3. Terminology
3.1 Definitions—Terms used in this test method are in accordance with Terminology D 883.
3.2 Definitions of Terms Specific to This Standard:
3.2.1 acidity, n—the acid strength of a sample expressed in ppm hydrochloric acid.
4. Summary of Test Method
4.1 The isocyanate is mixed with an excess of methanol and a cosolvent. Additional acid is released into the solvent system
during urethane formation. The acid then is titrated potentiometrically with methanolic KOH, and the acidity present in the
isocyanate sample is calculated from the titer.
5. Significance and Use
5.1 This test method can be used for research or for quality control to characterize aromatic isocyanates and prepolymers of
moderate to high acidity. Acidity correlates with performance in some polyurethane systems.
6. Apparatus
6.1 250-mL Beakers.
6.2 50-mL Pipet or Repipet, Class A volumetric.
6.3 100-mL Pipet or Repipet, Class A volumetric.
6.4 Automatic Titration Equipment, such as: , capable of inflection detection and stirring the sample while, titrating, such as:
6.4.1 Titroprocessor, and Commerically-available Automatic Titration Apparatus,
6
6.4.2 Dosimat , with magnetic stirrer.
6.4.3Reference Electrode, with saturated LiCl/ethanol solution in both chambers.
1
This test method is under the jurisdiction ofASTM Committee D20 on Plastics and is the direct responsibility of Subcommittee D20.22 on Cellular Materials— - Plastics
and Elastomers.
Current edition approved March 10, 2003.Nov. 15, 2008. PublishedApril 2003.November 2008. Originally approved in 1997. Last previous edition approved in 19972003
as D6099-97.D 6099 - 03.
2
Annual Book of ASTM Standards, Vol. 08.01.
2
For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at service@astm.org. For Annual Book of ASTM Standards
volume information, refer to the standard’s Document Summary page on the ASTM website.
3
Annual Book of ASTM Standards, Vol. 15.05.
3
Available from American National Standards Institute (ANSI), 25 W. 43rd St., 4th Floor, New York, NY 10036, http://www.ansi.org.
*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 ----------------------
D6099–08
6.4.4
6.4.3 pH Glass Electrode, (see Note 2).
NOTE 2—A combination pH electrode with internal reference also may be used.
6.5 Magnetic Stirrer.
6.6 Stir Bars.
6.7 Watch Glasses.
6.8 Analytical Balance, capable of weighing to the nearest 1 mg.
7. Reagents and Materials
7.1 0.02 N KOH in Methanol—1.32 g KOH pellets (85 % KOH)/1000 mL methanol, standardized with potassium hydrogen
phthalate (KHP).
7.2 Toluene or 1,2,4–Trichlorobenzene (TCB), dried for 24 h over molecular sieves.
7.3 Anhydrous Methanol.
8. Sampling
8.1Since organic isocyanates react with atmospheric moisture, take special precautions in sampling. (Warning —Organic
isocyanates are toxic when they are absorbed through the skin or when the vapors are breathed.) (Warning—Provide adequate
ventilation and wear protective gloves and eyeglasses.) Usual sampling methods, for example, sampling with an open drum thief,
eve
...