ASTM D3192-09(2014)

NOTICE: This standard has either been superseded and replaced by a new version or withdrawn.
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Designation: D3192 − 09 (Reapproved 2014)
Standard Test Methods for
Carbon Black Evaluation in NR (Natural Rubber)
This standard is issued under the fixed designation D3192; 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 expectancy, and utility of rubber products. These test methods
provide a natural rubber formulation and directions for evalu-
1.1 These test methods cover the standard materials, test
ating carbon black intended for use in rubber products.
formulation, mixing procedure, and test methods for the
evaluation and production control of carbon blacks in natural 3.2 These test methods may be used to characterize carbon
rubber (NR). black in terms of specific properties of the standard compound.
These test methods are useful for the quality assurance of
1.2 The values stated in SI units are to be regarded as the
carbon black production. They may also be used for the
standard. The values in parentheses are for information only.
preparation of reference compounds, to confirm the day-to-day
1.3 This standard does not purport to address all of the
reliability of testing operations used in the rubber industry, for
safety concerns, if any, associated with its use. It is the
the evaluation of experimental compounds, and quality control
responsibility of the user of this standard to establish appro-
of production compounds.
priate safety and health practices and determine the applica-
bility of regulatory limitations prior to use.
4. Standard Test Formula
4.1 Standard Formula:
2. Referenced Documents
A
Material IRM No. Quantity, parts
2.1 ASTM Standards:
by mass
D412 Test Methods forVulcanized Rubber andThermoplas-
B
Natural rubber . 100.00
tic Elastomers—Tension
Stearic acid 21 3.00
D1799 Practice for Carbon Black—Sampling Packaged
Zinc oxide 91 5.00
Benzothiazyl disulfide 2 0.60
Shipments
Sulfur 31 2.50
D1900 Practice for Carbon Black—Sampling Bulk Ship-
C
Carbon black . 50.00
ments
Total 161.10
D
Batch factor:
D2084 Test Method for Rubber Property—Vulcanization
Test Method A—Mill 4.00
Using Oscillating Disk Cure Meter
Test Method B—Internal Mixer 6.00
D3182 PracticeforRubber—Materials,Equipment,andPro-
Test Method C—Miniature Internal 0.40
Mixer
cedures for Mixing Standard Compounds and Preparing
_____________
Standard Vulcanized Sheets
D4483 Practice for Evaluating Precision for Test Method
A
IRM 91 is available from R. E. Carroll, Inc., 1570 North OldenAve., Trenton, NJ
Standards in the Rubber and Carbon Black Manufacturing
08638; (800) 257–9365. IRM 2, IRM 21, and IRM 31 are available from Akron
Rubber Development Lab, 2887 Gilchrist Road, Akron, OH 44305; (330)
Industries
794–6600.
B
SMR L and STR L have been found to give satisfactory performance. Other
3. Significance and Use
sources of rubber may give satisfactory results but have not been investigated by
Subcommittee D24.71. Other sources of rubber should be checked to ensure that
3.1 The major portion of carbon black consumed by the
results equivalent to SMR L are attained before using in this test method.
C
rubber industry is used to improve the physical properties, life
Use 75.00 parts by mass of carbon blacks in the N-800 and N-900 series.
D
Weigh rubber and carbon black to the nearest 1 g, sulfur and accelerator to the
nearest 0.02 g, and all other compounding materials to the nearest 0.1 g.
These test methods are under the jurisdiction of ASTM Committee D24 on
5. Sampling and Sample Preparation
Carbon Black and are the direct responsibility of Subcommittee D24.71 on Carbon
Black Testing in Rubber.
5.1 Samples shall be taken in accordance with Practice
Current edition approved Sept. 1, 2014. Published November 2014. Originally
D1799 or Practice D1900.
approved in 1973. Last previous edition approved in 2009 as D3192 – 09. DOI:
10.1520/D3192-09R14.
5.2 The carbon black shall be conditioned before weighing
For referenced ASTM standards, visit the ASTM website, www.astm.org, or
and mixing by heating for1hinan oven set at 125 6 1°C.The
contact ASTM Customer Service at service@astm.org. For Annual Book of ASTM
black shall be placed in an open vessel of suitable dimensions
Standards volume information, refer to the standard’s Document Summary page on
the ASTM website. so that the depth of black is no more than 10 mm during
Copyright © ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States
D3192 − 09 (2014)
conditioning.The black conditioned as above shall be stored in
Add the stearic acid. 1.0 2.0
a closed moisture-proof container until ready for mixing.
Add the zinc oxide and one-half the carbon black. 1.5 3.5
6. Mixing Procedures
Add the remainder of the carbon black. 1.5 5.0
6.1 For general mixing procedure refer to Practice D3182.
The following mixing procedures are acceptable in testing
Add the sulfur. Clean the mixer throat and the top of
carbon black: (1) Test Method A—Mill Mix, (2) Test Method
the ram. 1.0 6.0
B—Internal Mixer, and (3)Test Method C—Miniature Internal
Dump at 7 min. 1.0 7.0
Mixer.
Subtotal 7.0
6.1.1 Test Method A—Mill Mix:
Set the mill opening at 0.80 mm (0.032 in.) and
maintain the roll temperature at 70 ± 5°C.
Duration, Accumulative,
Pass the rolled batch endwise through the mill six
min min
times. 2.0 9.0
Set the mill opening at 1.4 mm (0.055 in.) and
adjust and maintain roll temperature at 70 ± 5°C. 0 0
Open the mill to give a minimum stock thickness of
6 mm (0.25 in.) and pass the stock through the rolls
Add rubber and band on the front roll.
four times, folding it back on itself each time. 1.0 10.0
Make two ⁄4 cuts from each side. 2.0 2.0
Total Time 10.0
Set mill opening at 1.65 mm (0.065 in.).
6.1.2.1 Check the batch mass and record. If outside of the
Add stearic acid.
range from 961.8 to 971.4 g, reject the batch. From this stock,
Make one ⁄4 cut from each side. 2.5 4.5
cut enough sample to allow testing of curing characteristics in
Add sulfur, accelerator, and zinc oxide.
accordance with Test Method D2084, if desired.
Make two ⁄4 cuts from each side. 2.0 6.5
6.1.2.2 Open the mill and sheet off to produce a stock
Add all the black.
thickness of 2.2 mm (0.085 in.).
When that portion of the carbon black that was
6.1.2.3 Unless otherwise specified, condition the sheeted
added has dropped through to the mill pan and the
bank is dry, make two ⁄4 cuts from each side. compoundfor1to24hat23 63°C(73.4 65.4°F)atarelative
Open the mill to 1.9 mm (0.075 in.) and add the
humidity not greater than 55 %. For maximum precision,
carbon black from the mill pan until all is
condition for 1 to 24 h in a closed container to prevent
incorporated.
Make three ⁄4 cuts from each side. 7.5 14.0 absorption of moisture from the air, or in an area controlled at
35 6 5 % relative humidity in accordance with Practice
Note—Do not cut any stock while free carbon black
D3182. Vulcanize and test in accordance with Section 7.
is evident in the bank or on the milling surface. Be
certain to return any pigments that drop through the
6.1.3 Test Method C—Miniature Internal Mixer:
mill to the milling stock.
6.1.3.1 Pigment Masterbatch Preparation—Mill Mix:
Set the mill opening at 0.80 mm (0.032 in.) and
Duration, Accumulative,
pass the rolled batch endwise through the mill six
min min
times. 2.0 16.0
(Batch Factor 4.00) Set the mill opening at 1.4 mm
(0.055 in.) and adjust and maintain roll temperature
Open the mill to give a minimum stock thickness of
at 70 ± 5°C. 0.0 0.0
6 mm (0.25 in.) and pass the stock through the rolls
four times, folding it back on itself each time. 1.0 17.0
Add rubber and band on the front roll.
Total Time 17.0
Make two ⁄4 cuts from each side. 2.0 2.0
6.1.1.1 Check the batch mass and record. If outside of the
Set mill opening at 1.65 mm (0.065 in.).
range from 641.2 to 647.6 g, reject the batch. From this stock,
Add stearic acid.
Make one ⁄4 cut from each side. 2.5 4.5
cut enough sample to allow testing of or curing characteristics
in accordance with Test Method D2084, if desired.
Add sulfur, accelerator, and zinc oxide.
6.1.1.2 Open the mill and sheet off to produce a thickness of 3
Make two ⁄4 cuts from each side. 2.0 6.5
2.2 mm (0.085 in.).
Set the mill opening at 0.80 mm (0.032 in.), and
6.1.1.3 Cool on a flat, dry metal surface, at a temperature of
pass the rolled batch endwise through the mill six
23 6 3°C for 1 to 24 h. Unless the relative humidity of the
times. 2.0 8.5
laboratory is controlled at 50 6 5 %, the sheeted stock should
Check the batch mass and if outside of the range
be cooled and stored in a closed container to prevent moisture
from 442.2 to 446.6 g, reject the batch. 0.5 9.0
absorption.
Set the mill opening to 1.5 mm (0.060 in.), band the
6.1.2 Test Method B—Internal Mixer:
stock. Sheet off. 1.0 10.0
Duration, Accumulative,
Total Time 10.0
min min
Adjust the internal mixer temperature to create a (1) Cool on a flat, dry metal surface, at a temperature of 23
dump temperature between 110 and 125°C.
6 3°C. Unless the relative humidity of the laboratory is
Close the discharge gate, start the rotor, raise the
controlled at 50 6 5 %, this masterbatch should be cooled and
ram, and charge the materials as described.
Lower the ram after each operation. 0 0
stored in a closed container to prevent moisture absorption.
NOTE 1—This pigment masterbatch should be used within 6 weeks or
Add the rubber. 0.5 0.5
discarded and a new batch prepared.
Add the benzothiazyl disulfide. 0.5 1.0
6.1.3.2 Carbon Black—Miniature Internal Mixer:
D3192 − 09 (2014)
(1) Mix with the head temperature of the miniature internal 7.2 For measuring vulcanization parameters by the cureme-
mixer maintained at 60 6 3°C and the unloaded slow rotor ter in accordance with Test Method D2084, use the 6-mm
speed at 6.3 to 6.6 rad/s (60 to 63 r/min). (0.25-in.) thickness samples that were previously prepared.
(2) Cut the pigment masterbatch prepared in 6.4.1 into 7.2.1 The recommended standard test conditions are 1.7 Hz
strips approximately 20-mm (0.75-in.) wide and weigh out (100 cpm) oscillation frequency, 1 6 0.03° amplitude of
44.44 g. oscillation, and 160 6 0.3°C die temperature using the micro
(3) Weigh out 20.00 g of carbon black sample. die system.
7.2.2 The recommended standard test parameters are M ,
Duration, Accumulative, L
min min
M , t , t' (50) and t' (90).
H s1 c c
Charge the mixing chamber with the masterbatch
strips, and start the timer. 0.0 0.0
8. Precision and Bias
Masticate the masterbatch. 0.5 0.5
8.1 This precision and bias statement has been prepared in
accordance with Practice D4483. Refer to Practice D4483 for
Add carbon black, use ram to work all of sample
terminology and other statistical details.
into chamber, sweep down orifice, and lower ram. 1.0 1.5
8.2 Precision—The precision results in this precision and
Allow the batch to mix. 1.5 3.0
Total Time 3.0 bias section give an estimate of the precision of this test
method with the materials (rubbers, carbon blacks, and so
(4) Turn off the motor, raise the ram, remove the mixing
forth) used in the particular interlaboratory program described
chamber and unload the batch. Record the batch temperature if
in 8.3 through 8.5.2.3. The precision parameters should not be
desired.
used for acceptance or rejection testing of any group of
(5) With the mill at room temperature, pass the batch
materials without documentation that they are applicable to
through the mill set at 0.80 mm (0.032 in.). Fold it on itself and
those particular materials and the specific testing protocols of
feed it back through the mill five more times, always keeping
the test method.
the grain in the same direction and folding it on itself each
time. 8.3 Mill Mix—Test Method A—A Type 2 interlaboratory
(6) Checkthebatchmassandrecord.Ifoutsideoftherange precision program was conducted in 1990. Both repeatability
from 64.12 to 64.76 g, reject the batch. and reproducibility represent short-term testing conditions.
(7) For testing of stress-strain, pass the batch through the Nine laboratories tested four carbon blacks (SRBs A-4, B-4,
mill to produce a stock thickness of 2.2 mm (0.085 in.). D-4, and F-4) once on each of two different days. Test results
(8) For testing of curing characteristics in accordance with were obtained in accordance with Test Methods D412 and are
Test Method D2084, pass the batch through the mill to produce
expressed as differences from IRB 6. A test result is the value
a minimum stock thickness of 6 mm (0.25 in.). obtained from a single determination. Acceptable difference
(9) Cool on a flat, dry metal surface, at a temperature of 23
values were not measured (see Table 1).
6 3°C for 1 to 24 h. Unless the relative humidity of the 8.3.1 Repeatability:
laboratory is controlled at 50 6 5 %, the sheeted stock should 8.3.1.1 Tensile Stress at 300% Elongation—The pooled
be cooled and stored in a closed container to prevent moisture repeatability of Test Methods D3192 Method A (using Test
absorption. Methods D412 Method A) tensile stress at 300 % elongation
has been established as 1.01 MPa (146 psi). Two single test
results (or determinations) that differ by more than 1.01 MPa
7. Preparation and Testing of Vulcanizates
(146 psi) must be considered suspect, that is, to have come
7.1 For stress-strain testing, prepare test slabs and vulcanize
fromdifferentsamplepopulations.Suchadecisiondictatesthat
them in accordance with Practice D3182.
some appropriate action be taken.
7.1.1 The recommended standard cures are 30 min at 145°C
8.3.1.2 Tensile Strength—The pooled repeatability of Test
for ASTM N-type carbon black, and 30 and 50 min at 145°C
Methods D3192 MethodA(using Test Methods D412 Method
for ASTM S-type carbon black.
A) tensile strength has been established as 1.70 MPa (246 psi).
7.1.2 Condition vulcanizates of compounds at a temperature
Two single test results (or determinations) that differ by more
of 23 6 2°C (73 6 3.6°F) for at least 16 h and for not more
than 1.70 MPa (246 psi) must be considered suspect, that is, to
than 96 h before preparing and testing, unless otherwise
have come from different sample populations. Such a decision
specified.
dictates that some appropriate action be taken.
8.3.1.3 Ultimate Elongation—The pooled repeatability of
NOTE 2—Quality control of rubber production may require testing
within 1 to6hto provide close surveillance of the plant operation;
Test Methods D3192 Method A (using Test Methods D412
however, slightly different results may be obtained.
MethodA) ultimate elongation
...