ASTM D4663-98(2004)

Standard Test Method for Polyurethane Raw Materials Determination of Hydrolyzable Chlorine of Isocyanates

SCOPE
1.1 This test method determines the hydrolyzable chlorine content of toluene-2,4-diisocyanate, toluene-2,6-diisocyanate, or mixtures of the two. This test method may also be applied to other isocyanates of suitable solubility. (See Note 0.) The main sources of hydrolyzable chlorine in the isocyanates are carbamoyl chloride and dissolved phosgene. Both of these compounds react with alcohols and water, forming ureas, carbamates, carbon dioxide, and hydrochloric acid. (See Note 2.)
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
This test method may be applicable with crude polymeric isocyanates. However, the precision with crude polymeric isocyanates has not been established.Note 2
There is no equivalent ISO standard.

General Information

• Status: Historical
• Publication Date: 29-Feb-2004
• ICS: 83.080.10 - Thermosetting materials
• Technical Committee: D20 - Plastics
• Drafting Committee: D20.22 - Cellular Materials - Plastics and Elastomers

Relations

• Replaces: ASTM D4663-98 - Standard Test Method for Polyurethane Raw Materials Determination of Hydrolyzable Chlorine of Isocyanates
• Effective Date: 01-Mar-2004
• Replaced By: ASTM D4663-10 - Standard Test Method for Polyurethane Raw Materials Determination of Hydrolyzable Chlorine of Isocyanates
• Effective Date: 01-Mar-2004
• Referred By: ASTM D4661-23 - Standard Test Methods for Polyurethane Raw Materials: Determination of Total Chlorine in Isocyanates
• Effective Date: 01-Mar-2004
• Referred By: ASTM D1786-21 - Standard Specification for Toluene Diisocyanate
• Effective Date: 01-Mar-2004

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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D4663–98 (Reapproved 2004)
Standard Test Method for
Polyurethane Raw Materials: Determination of Hydrolyzable
Chlorine of Isocyanates
This standard is issued under the fixed designation D4663; 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* 3.2 Description of Term Specific to This Standard.
3.2.1 hydrolyzable chloride—the low level chlorine-
1.1 This test method determines the hydrolyzable chlorine
containing components of the isocyanate, such as carbamoyl
content of toluene-2,4-diisocyanate, toluene-2,6-diisocyanate,
chlorides, which react with water or alcohol to form HCl.
or mixtures of the two.This test method may also be applied to
other isocyanates of suitable solubility. (See Note 1.) The main
4. Summary of Test Method
sources of hydrolyzable chlorine in the isocyanates are car-
4.1 The hydrolyzable chlorine reacts with methanol, liber-
bamoyl chloride and dissolved phosgene. Both of these com-
ating hydrochloric acid. The titratable chlorides are then
pounds react with alcohols and water, forming ureas, carbam-
determined potentiometrically using a standard silver nitrate
ates, carbon dioxide, and hydrochloric acid. (See Note 2.)
solution.
1.2 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the
5. Significance and Use
responsibility of the user of this standard to establish appro-
5.1 This test method can be used for research or for quality
priate safety and health practices and determine the applica-
control to characterize toluene diisocyanates. Hydrolyzable
bility of regulatory limitations prior to use.
chlorine correlates with performance in some polyurethane
NOTE 1—This test method may be applicable with crude polymeric
systems.
isocyanates. However, the precision with crude polymeric isocyanates has
not been established.
6. Interferences
NOTE 2—There is no equivalent ISO standard.
6.1 Thiocyanate, cyanide, sulfide, bromide, iodide, or other
substances capable of reacting with silver ion, as well as
2. Referenced Document
2 substances capable of reducing silver ion in acid solution, will
2.1 ASTM Standards:
interfere with the determination.
D883 Terminology Relating to Plastics
D1193 Specification for Reagent Water
7. Apparatus
7.1 Weighing Bottle, or any device capable of weighing a
3. Terminology
liquid by difference to the nearest 0.1 g.
3.1 Definitions—For definitions of terms used in this test
7.2 Hot Plate, with magnetic stirrer.
method see Terminology D883.
7.3 Potentiometric Titrator, or pH meter.
7.4 Silver-Silver Chloride Electrode.
This test method is under the jurisdiction ofASTM Committee D20 on Plastics
7.5 Silver or Glass Electrode.
and is the direct responsibility of Subcommittee D20.22 on Cellular Materials -
7.6 Calomel Electrode.
Plastics and Elastomers.
Current edition approved March 1, 2004. Published June 2004. Originally
8. Reagents and Materials
approved in 1987. Last previous edition approved in 1998 as D4663 - 98. DOI:
10.1520/D4663-98R04.
8.1 Purity of Reagents—Use reagent grade chemicals in all
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
tests. Unless otherwise indicated, it is intended that all reagents
contact ASTM Customer Service at [e-mail]. For Annual Book of ASTM
conform to the specifications of the Committee on Analytical
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.
D4663–98 (2004)
NOTE 4—Some isocyanates will not react readily and slight warming
Reagents of the American Chemical Society where such
may be necessary to initiate reaction. Other isocyanates may react, as
specifications are available. Other grades may be used, pro-
indicated by warming of reactants, but may not form crystals.
vided it is first ascertained that the reagent is of sufficiently
NOTE 5—Add the water quickly to keep the reactants from solidifying
high purity to permit its use without lessening the accuracy of
and to minimize the loss of HCl.
the determination.
11.2 Wash the sides of the beaker with water and remove
8.2 Purity of Water—Unless otherwise indicated, references
and wash the stirring bar. Cool the beaker in an ice bath to
to water shall be understood to mean reagent water as defined
about 10°C and add 10 drops of HNO . Titrate potentiometri-
by Type I of Specification D1193.
cally with 0.01 NAgNO solution using a silver-silver chloride
8.3 Concentrated Nitric Acid (HNO sp gr 1.42).
electrode pair. If the chloride content is greater than 0.2 %, use
8.4 Methanol.
0.1 N instead of 0.01 N A
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