ASTM D4877-98

Standard Test Method for Polyurethane Raw Materials Determination of APHA Color in Isocyanates

SCOPE
1.1 This test method measures the color of clear liquids. It is applicable only to materials whose color-producing bodies have light-absorption characteristics similar to those of the standards used.  (See Test Method D1209 and Note 1.)
1.2 The values stated in SI units are to be regarded as the standard.
1.3 This standard does not purport to address all of the safety problems, 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. For specific hazards statements see 7.1 and Note 2. Note 1-There is no equivalent ISO standard.

General Information

• Status: Historical
• Publication Date: 09-Jul-1998
• ICS: 71.080.30 - Organic nitrogen compounds
• ICS: 83.040.30 - Auxiliary materials and additives for plastics
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.22 - Cellular Materials - Plastics and Elastomers

Relations

• Replaced By: ASTM D4877-04 - Standard Test Method for Polyurethane Raw Materials: Determination of APHA Color in Isocyanates
• Effective Date: 01-Mar-2004
• Referred By: ASTM D1786-21 - Standard Specification for Toluene Diisocyanate
• Effective Date: 10-Jul-1998

Standards Content (Sample)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
Contact ASTM International (www.astm.org) for the latest information
Designation: D 4877 – 98
Standard Test Method for
Polyurethane Raw Materials: Determination of APHA Color
in Isocyanates
This standard is issued under the fixed designation D 4877; 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 4. Summary of Test Method
1.1 This test method measures the color of clear liquids. It 4.1 The color of the material to be tested is compared to a
is applicable only to materials whose color-producing bodies series of platinum cobalt color standards, designated by mg of
have light-absorption characteristics similar to those of the Pt/mL of standard solution. The results are reported as the color
standards used. (See Test Method D 1209 and Note 1.) standard, which best matches the sample (Note 2).
1.2 The values stated in SI units are to be regarded as the
NOTE 2—Color of liquids also can be measured by visible spectroscopy
standard.
and the results converted to any of several color scales. These results can
1.3 This standard does not purport to address all of the
be converted to the APHA scale by appropriate manipulations, as for
safety concerns, if any, associated with its use. It is the example in Test Method D 5386.
responsibility of the user of this standard to establish appro-
5. Significance and Use
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use. For specific 5.1 This test method can be used for research or for quality
control to characterize isocyanates used in polyurethane prod-
hazards statements see 7.1 and Note 2.
ucts.
NOTE 1—Although this test method and ISO 6271-1981 differ in some
5.2 For toluene diisocyanate, results from this test method
details, data obtained using either are technically equivalent.
may relate to reactivity or performance in polyurethane sys-
2. Referenced Documents tems.
2.1 ASTM Standards:
6. Apparatus
D 883 Terminology Relating to Plastics
4 6.1 Nessler Tubes, matched, 100-mL tall-form.
D 1193 Specification for Reagent Water
D 1209 Test Method for Color of Clear Liquids (Platinum-
7. Reagents and Materials
Cobalt Scale)
7.1 Purity of Reagents—Reagent grade chemicals shall be
D 5386 Test Method for Color of Liquids Using Tristimulus
5 used in all tests. Unless otherwise indicated, it is intended that
Colorimetry
all reagents conform to the specifications of the Committee on
2.2 ISO Standards:
Analytical Reagents of the American Chemical Society where
ISO 6271-1981 Clear Liquids—Estimation of Color by the
6 such specifications are available. Other grades may be used,
Platinum Cobalt Scale
provided it is first ascertained that the reagent is of sufficiently
3. Terminology high purity to permit its use without lessening the accuracy of
the determination.
3.1 For definitions of terms used in this test method see
7.2 Purity of Water—Unless otherwise indicated, references
Terminology D 883.
to water shall be understood to mean reagent water as defined
by Type IV or better of Specification D 1193.
This test method is under the jurisdiction of ASTM Committee D-20 on Plastics
7.3 Cobaltous Chloride Hexahydrate (CoCl ·6H O).
2 2
and is the direct responsibility of Subcommittee D20.22 on Cellular Plastics.
7.4 Concentrated Hydrochloric Acid (sp. gr. 1.19).
Current edition approved July 10, 1998. Published January 1999. Originally
published as D 4877 – 88. Last previous edition D 4877 – 93.
See Standard Methods for the Examination of Water, Sewage, and Industrial
Wastes, AM. Public Health Assn., 1015 15th St. NW Washington, DC 20005. Reagent Chemicals, American Chemical Society Specifications, American
Annual Book of ASTM Standards, Vol 08.01. Chemical Society, Washington, DC. For suggestions on the testing of reagents not
Annual Book of ASTM Standards, Vol 11.01. listed by the American Chemical Society, see Analar Standards for Laboratory
Annual Book of ASTM Standards, Vol 06.04. Chemicals, BDH Ltd., Poole, Dorset, U.K., and the United States Pharmacopeia
Available from American National Standards Institute, 11 W. 42nd St., 13th and National Formulary, U.S. Pharmacopeial Convention, Inc. (USPC), Rockville,
Floor, New York, NY 10036. MD.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D 4877
TABLE 1 Color Standards
7.5 Potassium Chloroplatinate (K PtCl ).
2 6
Number 500 Standard,
Color Standard Number Water, mL
8. Sampling
mL
8.1 Since organic isocyanates react with atmospheric mois-
1 0.2 99.8
3 0.6 99.4
ture, special precautions must be taken in sampling (Caution:
5 1.0 99.0
Note 3). Usual sampling methods (for example, sampling an
10 2.0 98.0
open drum with a thief), even when carried out rapidly, can
15 3.0 97.0
18 3.6 96.4
cause contamination of the sample with insoluble urea. There-
20 4.0 96
...