ASTM D6979-03
(Test Method)Standard Test Method for Polyurethane Raw Materials: Determination of Basicity in Polyols, Expressed as Percent Nitrogen
Standard Test Method for Polyurethane Raw Materials: Determination of Basicity in Polyols, Expressed as Percent Nitrogen
SIGNIFICANCE AND USE
This test method is suitable for quality control, as a specification test, and for research. The results are measures of batch-to-batch uniformity and may be useful in estimating reactivity.
5.1.1 The percent nitrogen can be used to characterize a polyol or indicate amounts of certain components in a polyol blend.
5.1.2 It is permissible to also express the results in equivalents of base per gram of sample, if desired.
SCOPE
1.1 This test method measures the basic constituents in polyols that are soluble in glacial acetic acid and reactive with perchloric acid. Samples containing 0.3 - 10 % nitrogen have been evaluated by this method. This test method is applicable to polyether polyols and polyether polyol blends that are used in urethane reactions. (See Note 1.)
1.2 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 health practices and determine the applicability of regulatory limitations prior to use.
Note 1—There is no equivalent ISO standard.
General Information
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Standards Content (Sample)
NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation:D6979–03
Standard Test Method for
Polyurethane Raw Materials: Determination of Basicity in
Polyols, Expressed as Percent Nitrogen
This standard is issued under the fixed designation D 6979; 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 (e) indicates an editorial change since the last revision or reapproval.
1. Scope to a potentiometric end point with a standardized solution of
perchloric acid in acetic acid. Results are reported as percent
1.1 This test method measures the basic constituents in
nitrogen.
polyols that are soluble in glacial acetic acid and reactive with
perchloric acid. Samples containing 0.3 – 10 % nitrogen have
5. Significance and Use
been evaluated by this method. This test method is applicable
5.1 This test method is suitable for quality control, as a
to polyether polyols and polyether polyol blends that are used
specification test, and for research. The results are measures of
in urethane reactions. (See Note 1.)
batch-to-batch uniformity and may be useful in estimating
1.2 This standard does not purport to address all of the
reactivity.
safety concerns, if any, associated with its use. It is the
5.1.1 The percent nitrogen can be used to characterize a
responsibility of the user of this standard to establish appro-
polyol or indicate amounts of certain components in a polyol
priate safety and health practices and determine the applica-
blend.
bility of regulatory limitations prior to use.
5.1.2 It is permissible to also express the results in equiva-
NOTE 1—There is no equivalent ISO standard.
lents of base per gram of sample, if desired.
2. Referenced Documents
6. Apparatus
2.1 ASTM Standards:
6.1 Potentiometric Automatic Titrator
D 883 Terminology Relating to Plastics
6.2 Autotitrator Buret with Dosing Device, 20-mL
E 180 Practice for Determining the Precision of ASTM
6.3 pH Glass Electrode and Reference Electrode or a
Methods for Analysis and Testing of Industrial Chemicals
Combination Glass Electrode
E 691 Practice for Conducting an Interlaboratory Study to
6.4 Analytical Balances, capable of weighing to the nearest
Determine the Precision of a Test Method
0.01g and 0.0001 g
6.5 Magnetic Stirrer/Hotplate
3. Terminology
3.1 Definitions—For definitions of terms used in this test
7. Reagents and Materials
method see Terminology D 883.
7.1 Purity of Reagents—Use reagent-grade chemicals in all
3.2 Definitions of Terms Specific to This Standard:
tests. Unless otherwise indicated, it is intended that all reagents
3.2.1 percent nitrogen—the quantity of perchloric acid-
conform to the specifications of the Committee on Analytical
titratable base, expressed as a weight percentage of nitrogen in
Reagents of the American Chemical Society where such
a sample. 3
specifications are available. It is permissible to use other
grades provided it is first ascertained that the reagent is of
4. Summary of Test Method
sufficiently high purity to permit its use without lessening the
4.1 The sample is dissolved in glacial acetic acid. The
accuracy of the determination.
resulting single-phase solution is titrated at room temperature
7.2 Acetic Acid, Glacial
7.3 Acetic Anhydride
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. Reagent Chemicals, American Chemical Society Specifications, American
Current edition approved November 1, 2003. Published January 2004. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
For referenced ASTM standards, visit the ASTM website, www.astm.org, or listed by the American Chemical Society, see Analar Standards for Laboratory
contactASTM Customer Service at service@astm.org. ForAnnual Book ofASTM Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Standards volume information, refer to the standard’s Document Summary page on and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
the ASTM website. MD.
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D6979–03
TABLE 1 Round-Robin Percent Nitrogen Data in Accordance
7.4 Perchloric Acid, (70 % nominal)
A
with Practice E 180
7.5 Perchloric acid inAceticAcid (0.10 N)—Prepare0.10N
B C D E F
Material Average S S r R df
perchloric acid in acetic acid. For example, in a 1000-mL r R
A 0.317 0.0007 0.0018 0.0020 0.0050 5
volumetric flask dissolve 8.7 mL of perchloric acid in 500 mL
B 2.51 0.0046 0.0053 0.0129 0.0148 5
of glacial acetic acid; add 25 mLof acetic anhydride and dilute
C 5.86 0.0079 0.0139 0.0221 0.0392 5
to volume with glacial acetic acid.
D 9.45 0.0220 0.0217 0.0616 0.0618 5
A
Values in units of percent nitrogen.
NOTE 2—Perchloric Acid—is extremely irritating to the skin, eyes and
B
S = within-laboratory standard deviation of the replicates.
r
mucous membrane; highly toxic via oral and inhalation routes; and can
C
S = between-laboratories standard deviation of the average.
R
form explosive mixtures when mixed with carbonaceous material or
D
r = within-laboratory repeatability limit = 2.8·S.
r
allowed to dry. Concentrated material shall only be used in a hood E
R = between-laboratories reproducibility limit = 2.8·S .
R
F
approvedforperchloricaciduse.Skincontact—washwithsoapandwater.
df = degrees of freedom in the data
...
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