ASTM D2396-94(2004)
(Test Method)Standard Test Methods for Powder-Mix Time of Poly(Vinyl Chloride) (PVC) Resins Using a Torque Rheometer
Standard Test Methods for Powder-Mix Time of Poly(Vinyl Chloride) (PVC) Resins Using a Torque Rheometer
SCOPE
1.1 These test methods cover the determination of the powder-mix time of a general-purpose poly(vinyl chloride) (PVC) resin.
1.2 The values stated in SI units are to be regarded as standard.
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.
There is no ISO standard covering the primary subject of these ASTM test methods.
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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NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.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:D2396–94 (Reapproved 2004)
Standard Test Methods for
Powder-Mix Time of Poly(Vinyl Chloride) (PVC) Resins
Using a Torque Rheometer
This standard is issued under the fixed designation D2396; 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.
TABLE 1 Powder-Mix Time of ASTM No. 1 Resin
1. Scope
DIDP Viscosity, Bowl Mean
1.1 These test methods cover the determination of the
Standard Number of
cP Temperature, Powder-Mix
Deviation Samples
powder-mix time of a general-purpose poly(vinyl chloride) A B
(millipascals-s) °C Time, s
(PVC) resin.
111 85 435 . 2
1.2 The values stated in SI units are to be regarded as
128 85 461 6.9 5
147 85 479 . 2
standard.
A
Viscosity was measured using a Brookfield RVF Viscometer, No. 1 spindle, 20
1.3 This standard does not purport to address all of the
r/min, at 23°C.
safety concerns, if any, associated with its use. It is the
B
The bowl temperature was measured at the thermocouple well.
responsibility of the user of this standard to establish appro-
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
into the resin and the resin granules become dry and free-
NOTE 1—There is no ISO standard covering the primary subject of flowing. When the mix reaches the dry and free-flowing state,
these ASTM test methods.
its resistance to stirring decreases and the motor torque needed
to maintain the same rotor speed decreases. By recording the
2. Referenced Documents
changes in motor torque with time, it is possible to measure the
2.1 ASTM Standards:
time required for a resin to absorb a plasticizer.
D883 Terminology Relating to Plastics
4.2 These test methods describe the use of two different
D1600 Terminology for Abbreviated Terms Relating to
mixing heads that can be mounted on a torque rheometer to
Plastics
perform this test.Test results obtained with these mixing heads
are compared in Section 14.
3. Terminology
4.2.1 A sigma mixing head is used in Test Method A.
3.1 General:
4.2.2 A planetary mixing head is used in Test Method B.
3.1.1 Definitions are in accordance with Terminology D883
and abbreviations are in accordance with Terminology D1600 5. Significance and Use
unless otherwise indicated.
5.1 The ability of PVC granules to accept a plasticizer and
become a dry free-flowing powder is related to the internal
4. Summary of Test Methods
pore structure of the resin, resin temperature, plasticizer
4.1 A sample of resin is heated and mixed in a bowl to the
temperature, and the plasticizer used. By choosing an appli-
test temperature.Ameasured amount of plasticizer is added to
cable plasticizer and maintaining a uniform temperature for the
the resin through a dispersing funnel. When the plasticizer is
resin and plasticizer, it is possible to classify resins by how
added to the resin, the mix becomes wet and an increase in
rapidly they absorb plasticizer. Resin suitability for a specific
motortorqueisneededtomaintainthesamerotorspeed.Asthe
intensive mixing operation can be ascertained using these test
mixingcontinuesintheheatedbowl,theplasticizerisabsorbed
methods.
6. Interferences
These test methods are under the jurisdiction of ASTM Committee D20 on
6.1 Resin—Each resin has a specific response in accepting a
Plastics and are the direct responsibility of Subcommittee D20.15 on Thermoplastic
plasticizer. Differences in powder-mix time between resins can
Materials.
be observed in the graph in the annex.
Current edition approved March 1, 2004. Published June 2004. Originally
´1
6.2 Plasticizer—Plasticizer viscosity directly affects
approved in 1969. Last previous edition approved in 1999 as D2396 - 94 (1999) .
DOI: 10.1520/D2396-94R04.
powder-mix time. Table 1 shows that an increase in diisodecyl
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
phthalate viscosity results in an increase in powder-mix time.
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
The data in Table 1 was generated in a single laboratory using
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. Test Method A.
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.
D2396–94 (2004)
TABLE 2 Interlaboratory Testing of ASTM No. 1 Resin
8.3 Clay.
A
Laboratory Powder-Mix Time, s Bowl Temperature, °C
9. Safety Precautions
1 454 82.0
2 454 85.0 9.1 Take care not to exceed the manufacturer’s recom-
3 450 85.5
mended damping limit on the sigma mixer because of the
A
The bowl temperature was measured at the thermocouple well.
danger of bending the blades.
9.2 Stop the mixer before cleaning the bowl and blades.
6.3 Temperature—The temperature at which the test is
10. Preparation of Torque Rheometer
performed will affect the powder-mix time. A lower test
temperature will have a longer powder-mix time.
10.1 Electronic Plasti-Corder Torque Rheometer:
10.1.1 Adjust the torque rheometer so that the strip chart
NOTE 2—It is also important to control the temperature of the plasti-
torque range reads 200 m-g at full scale.
cizer added to the resin. The powder-mix time can vary by as much as 3
10.1.2 Set chart speed to 10 mm/min.
s for each degree Fahrenheit difference in plasticizer temperature, as seen
in the graph in the annex.
10.1.3 Place pen on chart.
10.1.4 Connect the stock temperature measuring thermo-
6.4 Equipment—Differences between equipment can result
couple to the recorder and start the recorder.
in differences in powder-mix times. To equate equipment, it is
10.2 PL-2000 Computerized Torque Rheometer—Program
suggested that a specific powder-mix time be chosen and that
the PL-2000 Plasti-Corder for the test conditions of:
thebowltemperaturebeadjustedtoobtainthesametimeforall
Order: (Run information)
equipment. Table 2 shows the results from three laboratories
Operator: (Name)
using this technique to equate to a powder-mix time forASTM
Date: (Current date)
No. 1 resin usingTest MethodAto the value set by Laboratory
PL-Type: 2000
Mixer Type: Planetary
1.
Sample: PVC (source)
6.5 Rotor Speed—Observed with the planetary mixing head
Plasticizer: DIDP (source)
(see Test Method B) was a decrease in dry time when the rotor
Mixer Temperature: 88°C
Speed: 100 r/min
speed had been increased: 60 r/min @ 82°C using DIDP = dry
Meas. Range: 500 mg
time of 868 s; and 100 r/min @ 82°C using DIDP = dry time
Zero Suppr: 0 %
of 628 s. Damping: 1 s
Test Time: 20 min
Sample Weight: 400.00 g
7. Apparatus
Plasticizer Weight: 200.00 g
7.1 Torque Rheometer.
4 NOTE 3—When using equipment other than C. W. Brabender, refer to
7.2 Sigma Mixer 650-mL, or equivalent, and the disper-
the manufacturer’s suggested settings for their equipment.
sion trough shown in Fig. 1 for plasticizer distribution. (For
Test Method A.)
11. Procedures
7.3 Planetary Mixer, and the dispersion funnel shown in
11.1 Test Method A (Sigma Mixer):
Fig. 2 for plasticizer distribution. (For Test Method B.)
11.1.1 Attach the 650-mL oil (or electric) Sigma Mixer to
7.4 Balance, 0.1-g sensitivity.
the torque rheometer.
7.5 Container, 0.95 L size.
11.1.2 Adjust the mixer-jacket temperature to 88 6 1°C as
7.6 Beaker, 400-mL.
measured at the thermocouple well.
7.7 Funnel, for use with planetary mixer (see Test Method
11.1.3 Set the mixer speed to 60 6 1 r/min.
B).
11.1.4 Weightheresinandclayofthefollowingformulation
7.8 Ruler, with metric scale.
into the quart container and mix thoroughly with a spatula:
7.9 Paint Brush, 25.4 mm width.
Resin 225 6 0.1 g
7.10 Thermometer, range of 40 to 100°C with 0.2°C divi-
Clay 40 6 0.1 g
sions.
DIDP Plasticizer 124 6 0.1 g
7.11 Spatula.
11.1.5 Wet the dispersion trough and the 400-mL beaker
7.12 Viscometer, Brookfield RVF, or equivalent.
with plasticizer and drain both for 1 min. Tare the prewetted
beaker and weigh 124 g of DIDP.
8. Mat
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