ASTM D6605-00

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Designation:D6605–00
Standard Practice for
Determining the Color Stability of Hydrocarbon Resins After
Heating
This standard is issued under the fixed designation D 6605; 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. Significance and Use
1.1 This practice covers the determination of the color 4.1 This practice is useful for both quality control and
stability of a hydrocarbon resin by exposure to a specific research.
temperature for a defined time period in a forced draft oven.
5. Apparatus and Materials
1.2 Color stability is measured by the change in color of the
test resin, measured via the yellowness index color scale, in 5.1 Forced Draft Oven, with the ventilation set at maximum
capacity.
accordance with Practice E 313, or the procedure for Gardner
Color, Test Method D 6166. 5.2 Aluminum Block, equipped with a control thermocouple
(see Fig. 1).
1.3 The values stated in SI units are to be regarded as
standard. The values given in parentheses are for information 5.3 Temperature Indicator.
5.4 Glass Jars, 250 mL (8 oz), with suitably lined screw
only.
1.4 This standard does not purport to address all of the cap.
safety concerns, if any, associated with its use. It is the
NOTE 1—Tetrafluoroethylene (TFE) lined caps work well.
responsibility of the user of this standard to establish appro-
5.5 Balance, readable to at least 0.1g.
priate safety and health practices and determine the applica-
5.6 Shaker: used to facilitate the dissolution of the heat-
bility of regulatory limitations prior to use.
aged resin.
2. Referenced Documents 5.7 Spectrophotometer or Tristimulus Colorimeter.
2.1 ASTM Standards:
6. Reagents
D 6166 Test Method for Color of Naval Stores and Related
2 6.1 Reagent Grade Toluene, or other solvent, for dissolving
Products, (Instrumental Determination of Gardner Color)
resins.
E 313 Practice for Calculating Yellowness and Whiteness
Indices from Instrumentally Measured Color Coordinates.
7. Sample Preparation
3. Summary of Practice 7.1 Weigh 10.0 6 0.1 g of resin into the sample jar.
7.2 Tap each jar gently to flatten the resin layer.
3.1 Samples of the hydrocarbon resin to be tested are placed
in 250-mL (8-oz) glass jars and placed in a heating block that
NOTE 2—Avoid having resin stick to the wall of the jar, since this tends
is in a ventilated oven set at 175°C.The samples are kept in the to bias the results high.
oven for a given period of 5 h. At the end of this time, the
8. Procedure
samples are removed and allowed to cool. After cooling, the
8.1 Install the aluminum block (see Fig. 1) in the center of
samples are dissolved in toluene. The color of each aged
an electronically regulated oven with the ventilation set at
sample solution is measured and compared to an initial sample
maximum.
solution. This color change is a measure of the stability of the
8.2 Set the oven controls so that the control thermocouple
resin.
reads 175.0°C 6 0.5°C.
8.3 Warning—An increase or decrease in the oven tem-
This practice is under
...