ASTM D1387-89(2002)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D 1387 – 89 (Reapproved 2002)
Standard Test Method for
Saponification Number (Empirical) of Synthetic and Natural
Waxes
This standard is issued under the fixed designation D 1387; 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 5. Apparatus
1.1 This test method covers the determination of the saponi- 5.1 Analytical Balance.
fication number of synthetic waxes and natural waxes. 5.2 Boiling Chips, chemically resistant glass.
1.2 This test method is applicable to Fischer Tropsche, 5.3 Burets, two 50-mL capacity with 0.1-mL graduations.
microcrystalline, polyethylene, and Montan Ester waxes. 5.4 Erlenmeyer Flasks, 250-mL, alkali-resistant.
1.3 Certain synthetic waxes, notably copolymers of ethyl- 5.5 Hot Plate.
ene, exhibit poor reproducibility when running saponification 5.6 Reflux Condenser.
values. Reproducibility can be improved if cooking time in 7.2
6. Reagents and Materials
is extended from3hto 18–20 h.
1.4 Some oxidized polyethylene and other waxes with a 6.1 Purity of Reagents—Reagent-grade chemicals or
equivalent as specified in Practice E 200 shall be used in all
melt temperature above 100°C may give poor reproducibility.
1.5 Some dark-colored (Gardner Color 14) waxes may tests.
6.2 Hydrochloric Acid Standard (0.5 N).
obscure the color change of the indicator, resulting in poor
reproducibility. 6.3 Phenolphthalein Indicator Solution (10 g/litre)—
Dissolve1gof phenolphthalein in 100 mL of USSD3A
1.6 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the denatured ethanol or 95 % ethanol.
6.4 Potassium Hydroxide,Alcoholic Solution (6.6 g/litre)—
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- Dissolve 6.6 g of potassium hydroxide (KOH) in USSD3A
denatured ethanol or 95 % ethanol. Dilute to 1 L with the
bility of regulatory limitations prior to use.
ethanol.
2. Referenced Documents
6.5 Xylene.
2.1 ASTM Standards:
7. Procedure
E 200 Practice for Preparation, Standardization, and Stor-
age of Standard and Reagent Solutions for Chemical 7.1 Transfer approximately1gofthe sample, weighed to
the nearest 0.001 g to a 250-mL Erlenmeyer flask.
Analysis
7.2 Add 40 mL of xylene and a few boiling chips to the
3. Terminology
flask. Dissolve by heating on the hot plate to the boiling point
3.1 Definition: of xylene. As soon as the wax dissolves, remove from the hot
3.1.1 saponification number—the number of milligrams of plate and add 50.0 mL of 0.1 N ethanolic KOH solution from
potassium hydroxide required to hydrolyze1gofthe sample the buret. Fit the flask with a reflux condenser and reflux for 3
and is a measure of the amount of saponifiable matter present. h using the hot plate.
7.3 Remove the condenser from the flask, add 5 drops of the
4. Significance and Use
phenolphthalein solution and titrate the sample with 0.5 N HCl
4.1 This test method is used to determine the property of
until the pink color disappears. Reheat the sample to the
ester fu
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