ASTM D1986-91(2002)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D1986–91(Reapproved 2002)
Standard Test Method for
Determining the Apparent Viscosity of Polyethylene Wax
This standard is issued under the fixed designation D 1986; 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 viscos- 5.1 Brookfield Thermosel System, with LVT, LVF, or LVD
ity in centipoise of polyethylene wax using the Brookfield LVT 111 viscometer and SC 4-31 spindle.
or LVF viscometer and thermosel system.
6. Calibration
1.2 This standard does not purport to address all of the
safety concerns, if any, associated with its use. It is the 6.1 The viscometer is precalibrated using Newtonian fluids
provided by the manufacturer. No zero adjustment is provided
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica- since experience has shown that the zero point will not vary
due to changes in the spring. The viscometer and spindles are
bility of regulatory limitations prior to use.
precision equipment and should be kept from undue shock and
2. Referenced Documents
mishandling. Physical damage to the instrument will often
2.1 ASTM Standards: reveal itself as erratic or no oscillation of the pointer when the
E1 Specification forASTM Liquid-in-Glass Thermometers instrument, with or without the spindle in place, is operated in
air. When operating normally, the pointer will be stable and
3. Terminology
have free oscillation about the zero point in air.
3.1 Definitions:
6.2 The instrument may be further calibrated using standard
3.1.1 polyethylene wax—polymerized ethylene with a mo- reference fluids. Suitable fluids are available in nominal
lecular weight 2,000 to 10,000 and a density of 0.9 to 1.0
viscosities up to 15 000 mPa·s at 149°C (300°F). The proce-
g/cm . These polymers can be oxidized or copolymerized but dure for instrument calibration using standard reference fluids
should have a melt point lower than 140°C.
is not encompassed by this test method. Results obtained using
3.1.2 viscosity—the ratio of shear stress to shear rate. The standard reference fluids should not deviate from the nominal
viscosity of a liquid is a measure of the internal friction of the viscosity by more than 2 %.
liquid in motion. The units of viscosity is the pascal second.
6.3 The temperature controller of the type recommended for
For a Newtonian liquid, the viscosity is constant at all shear this procedure is factory calibrated and has control capability
rates. For a non-Newtonian liquid, viscosity will vary depend-
of 60.5 % of the control point (61.0°C at 175°C). To further
ing on shear rate. check the controller and further establish controller settings,
3.1.3 apparent viscosity—the viscosity determined by this
use the following procedure. Place a sufficient quantity of
test method and expressed in millipascal seconds. Its value polyethylene wax in the sample container to permit immersion
may vary with the spindle and rotational speed selected
of the appropriateASTM thermometer to the proper depth. Do
because many waxes are non-Newtonian. not permit the thermometer bulb to rest on the bottom of the
sample container. Suitable thermometers are shown in Speci-
4. Significance and Use
ficationE1.
4.1 This test method is used to determine a physical
6.4 Insert the thermometer through the insulating cover of
property of a wax and may determine the utility of the wax, as
the sample container and hold it in place at the point required
well as being a significant quality control test.
for proper immersion depth. Adjust the thermal controller to
provide the desired test temperature. Rotate the thermometer
during temperature reading to minimize the effect of thermal
gradients in the sample. Continue temperature readings and
ThistestmethodisunderthejurisdictionofASTMCommitteeD21onPolishes
controller adjustment until minimum deviation from test tem-
and is the direct responsibility of Subcommittee D21.02 on Raw Materials.
perature is obtained. Minimum deviation may vary between
Current edition approved Sept. 10, 2002. Published April 1991.
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
Standards volume information, refer to the standard’s Document Summary page
...