1、Designation: D3848 03 (Reapproved 2009)Standard Test Methods forRubberEvaluation of NBR (Acrylonitrile-ButadieneCopolymers) Mixed With Carbon Black1This standard is issued under the fixed designation D3848; the number immediately following the designation indicates the year oforiginal adoption or, i
2、n the case of revision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon () indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods specify the standard materials, testformula, mixing procedures,
3、 and test methods for the evalua-tion of acrylonitrile-butadiene rubber (NBR) mixed with car-bon black.1.2 The values stated in SI units are to be regarded as thestandard. The values given in parentheses are for informationonly.1.3 This standard does not purport to address all of thesafety concerns,
4、 if any, associated with its use. It is theresponsibility 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.2. Referenced Documents2.1 ASTM Standards:2D412 Test Methods for Vulcanized Rubber and
5、Thermo-plastic ElastomersTensionD1646 Test Methods for RubberViscosity, Stress Relax-ation, and Pre-Vulcanization Characteristics (Mooney Vis-cometer)D2084 Test Method for Rubber PropertyVulcanizationUsing Oscillating Disk Cure MeterD3182 Practice for RubberMaterials, Equipment, andProcedures for Mi
6、xing Standard Compounds and Prepar-ing Standard Vulcanized SheetsD3896 Practice for Rubber From Synthetic SourcesSamplingD4483 Practice for Evaluating Precision for Test MethodStandards in the Rubber and Carbon Black ManufacturingIndustriesD5289 Test Method for Rubber PropertyVulcanizationUsing Roto
7、rless Cure MetersD6204 Test Method for RubberMeasurement of Unvul-canized Rheological Properties Using Rotorless ShearRheometers3. Significance and Use3.1 These test methods are mainly intended for refereepurposes but may be used for quality control of rubberproduction. They may also be used in rese
8、arch and develop-ment work and for comparison of different samples in astandard test formula.3.2 These test methods may also be used to obtain values forcustomer acceptance of rubber.4. Standard Test Formula4.1 Standard Formula:IRM/SRMSRM Quantity, PartsMaterial No. By MassMasterbatch . 100.00 + XAZ
9、inc oxideB3.00Sulfur, coatedC. 1.50Stearic acidB1.00TBBSDB0.70 + XTotal mass 106.20 + XBatch factorsMillEMiniature internal mixerFAX = parts carbon black per 100 parts base polymer.BUse current IRM/SRM.CThe use of 2 % MgCO3coated sulfur is recommended. Standard 2 % MgCO3coated sulfur Lot No. M266573
10、-P is available from C. P. Hall Co., 4460 HudsonDrive, Stow, OH 44224.DN-tert-butyl-2-benzothiazolesulfenamide.EFor mill mixing, a batch factor should be selected to the nearest 0.5 to give aslarge as total mass as possible that will not exceed 525.0 g. Calculate all parts tothe nearest 0.01 part. W
11、eigh the masterbatch to the nearest 1 g, the sulfur and theaccelerator to the nearest 0.02 g, and all the other compounding materials to thenearest 0.1 g.FFor MIM mix, select a batch factor to give a batch that will fill the mixingchamber volume to 75 % capacity. Calculate all parts to the nearest 0
12、.1 g, thecompounding material blend to the nearest 0.01 g, and the individual compoundingmaterials, if used, to the nearest 0.001 g.For the MIM procedure, it is recommended that a blend of compoundingmaterials be prepared to improve accuracy in the weighing of the materials. The1These test methods a
13、re under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.23 on SyntheticRubbers.Current edition approved Sept. 1, 2009. Published December 2009. Originallyapproved in 1980. Last previous edition approved in 2003 as D3848 03. DOI:10.1520/D3848-03R
14、09.2For referenced ASTM standards, visit the ASTM website, www.astm.org, orcontact ASTM Customer Service at serviceastm.org. For Annual Book of ASTMStandards volume information, refer to the standards Document Summary page onthe ASTM website.1Copyright ASTM International, 100 Barr Harbor Drive, PO B
15、ox C700, West Conshohocken, PA 19428-2959, United Spound material blend is prepared by blending a proportional mass of eachmaterial in a biconical or a vee blender. A mortar and pestle may be used forblending small quantities.5. Sample Preparation5.1 Obtain and prepare the test samples in accordance
16、 withPractice D3896.6. Mixing Procedures6.1 Three mixing procedures are provided as follows:6.1.1 Method AMill Mix (6.2) and6.1.2 Method BMiniature Internal Mixer Mix (6.3).6.1.3 Method CInternal MixerNOTE 1It is not implied that comparable results will be obtained bythese test methods.6.2 Method AM
17、ill Mix Procedure:6.2.1 For general mixing procedures, refer to PracticeD3182.6.2.2 Mixing CycleInitial Mix:Accu-Dura- mula-tion, tive,min min6.2.2.1With the mill roll temperature set at 50 6 5C(122 6 9F) and the mill opening set at 1.40mm (0.055 in.), band the masterbatch on theslow roll without cu
18、tting.226.2.2.2Add sulfur slowly and evenly across the millat a uniform rate.246.2.2.3Add stearic acid. Make one34 cut from eachside after the stearic acid has been incorpo-rated.266.2.2.4Add the zinc oxide and the accelerator. 3 96.2.2.5Make three34 cuts from each side and cutthe batch from the mil
19、l.2116.2.2.6Set the rolls at 0.8 mm (0.032 in.). Pass therolled batch endwise through the mill six times.2136.2.2.7Open the mill to give a minimum batch thick-ness of 6 mm (0.25 in.) and pass the stockthrough the mill four times, folding it back onitself each time.1146.2.2.8Check the batch mass and
20、record. If it differsfrom the theoretical value by more than 0.5 %,discard the batch.6.2.2.9From this batch cut a sample for testing ofcompound viscosity in accordance with TestMethods D1646 or rheological properties in ac-cordance with Test Method D6204, vulcanizingcharacteristics in accordance wit
21、h Test MethodD2084, or Test Method D5289, or both, if theseare desired. Condition the sample for 1 to 24 hat 23 6 2C (73.4 6 3.6F) before testing.6.2.2.10If tensile stress is required, sheet off thecompound from the mill at a setting to give afinished gage of approximately 2.2 mm (0.085in.) by passi
22、ng the folded stock between therolls set at 506 5C (122 6 9F) four timesalways in the same direction to obtain the ef-fect of milling. Cool on a flat, dry metal surface.6.2.2.11For routine laboratory testing, condition thesheeted compound for 1 to 24 h at 23 6 2C(73.4 6 3.6F) and a relative humidity
23、 notgreater than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of moisture from the air orin an area controlled at 35 6 5 % relative hu-midity.6.3 Method BMiniature Internal Mixer (MIM) Procedure:6.3.1For general mixing procedures, refer to Prac-tice
24、D3182. Mix with the MIM mixing chambermaintained at 60 6 3C (140 6 5F) and withan unloaded rotor speed of 6.3 to 6.6 rad/s (60to 63 rpm).6.3.2Prepare the masterbatch by passing itthrough a mill one time with the temperatureset at 50 6 5C (122 6 9F) and an opening of0.5 mm (0.02 in.). Cut the sheet i
25、nto strips thatare approximately 25 mm (1 in.) wide, if de-sired.6.3.3 Mixing Cycle:6.3.3.1Feed the rubber strips into the mixing cham-ber and, when all are in, start the timer. Breakdown the rubber.0.5 0.56.3.3.2Add all the zinc oxide, sulfur, stearic acid,and TBBS which have previously been blende
26、dtogether, taking care to avoid any loss. Stopthe mixer briefly and sweep loose pigments intothe chamber with a brush.0.5 1.06.3.3.3Allow the compound to mix.6.3.3.4Turn off the motor, raise the ram, remove themixing chamber, and discharge the batch.Record the maximum batch temperature, if de-sired.
27、8.0 9.06.3.3.5D3848 03 (2009)2Pass the batch between the rolls of a millmaintained at 50 6 5C (122 6 9F) and 0.5mm (0.020 in.) opening once, then twice at 3.0mm (0.122 in.) opening.6.3.3.6Check the batch mass and record. If it differsfrom the theoretical value by more than 0.5 %,discard the batch.6.
28、3.3.7Cut a sample for testing of compound viscos-ity in accordance with Test Methods D1646 orrheological properties in accordance with TestMethod D6204, or vulcanizing characteristics inaccordance with Test Method D2084, or TestMethod D5289, if these are desired. Conditionthe sample 1 to 24 h at 23
29、6 2C (73.4 63.6F) before testing.6.3.3.8If stress strain testing is required, pass therolled stock end-wise through the mill six timeswith the mill temperature at 50 6 5C (12269F) and a roll separation of 0.8 mm (0.032in.).6.3.3.9If tensile stress is required, sheet off thecompound from the mill at
30、a setting to give afinished gage of approximately 2.2 mm (0.085in.) by passing the folded stock between themill rolls set at 50 6 5C (122 6 9F) fourtimes always in the same direction to obtain theeffect of milling. Cool on a flat, dry metal sur-face.6.3.3.10For routine laboratory testing, condition
31、thesheeted compound for 1 to 24 h at 23 6 2C(73.4 6 3.6F) and a relative humidity notgreater than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of moisture from the air orin an area controlled at 35 6 5 % relative hu-midity.6.4 Internal Mixer Procedur
32、e:6.4.1 For general mixing procedure refer to Practice D3182.6.4.2 Mixing Cycle-Initial Mix:Accu-Dura- mula-tion, tive,min min6.4.2.1Adjust the internal mixer temperature toachieve the discharge conditions outlined in6.2.2. Close the discharge gate, start the rotorat 8.1 rad/s (77 rpm) and raise the
33、 ram.006.4.2.2Charge one half the rubber, all of the zincoxide, carbon black, stearic acid, and then theother one half of the rubber. Lower the ram.53.0.53.56.4.2.3Allow the batch to mix. .5 4.06.4.2.4Raise the ram and clean the mixer throat andthe top of the ram. Lower the ram.2.0 6.06.4.2.5Allow t
34、he batch to mix until a temperature of170C (338F) or a total mixing time of 6 min isreached, whichever occurs first. Discharge thebatch.2.0 6.06.4.2.6Determine and record the batch mass; if themass differs by more than 0.5 % of the theo-retical mass, discard the batch.6.4.2.7Pass the batch immediate
35、ly through the stan-dard laboratory mill three times, set at 6.0 mm(0.25 in.) and 406 5C (104 6 9F).6.4.2.8Allow the batch to rest for 1 to 24 h.6.4.3 Final Mix:6.4.3.1 Adjust the internal mixer temperature to 40 6 5C(104 6 9F), turn off steam and turn on full cooling water tothe rotors, at 8.1 rad/
36、s (77 rpm), and raise the ram.Accu-Dura- mula-tion, tive,min min6.4.3.2Charge12 the batch, with all the sulfur andaccelerator rolled into this portion of the batchbefore feeding to the mixer. Add the remainingportion of the batch. Lower the ram.556.4.3.3Allow the batch to mix until a temperature of1
37、10 6 5C (230 6 9F) or a total mixing time of3 min is reached, whichever occurs first. Dis-charge the batch.2.5 3.06.4.3.4Determine the record the batch mass; if themass differs by more than 0.5 % of the theo-retical mass, discard it.6.4.3.5With the rolls of a standard laboratory millmaintained at 40
38、 6 5C (104 6 9F) and set at0.8 mm (0.0032 in.) opening, pass the rolledbatch endwise through the rolls six times.2.0 5.06.4.3.6Open the rolls to give a minimum thicknessof 6 mm (0.25 in.) and pass the compoundthrough four times, folding it back itself eachtime.1.0 6.06.4.3.7Cut enough samples for te
39、sting of compoundviscosity in accordance with Test MethodsD1646, or rheological properties in accordancewith Test Method D6204, or vulcanizing charac-teristics in accordance with Test MethodD2084, or Test Method D5289, if these are de-sired. Condition the sample for 1 to 24 h at 236 3C (73.4 6 5.4F)
40、 before testing.6.4.3.8If tensile stress is required, sheet off thecompound from the mill at a setting to give afinished of approximately 2.2 mm (0.085 in.) bypassing the folded stock between the rolls setat 506 5C (122 6 9F) four times always inthe same direction to obtain the effects of milldirect
41、ion. Cool on a flat, dry metal surface.D3848 03 (2009)36.4.3.9Four routine laboratory testing, condition thesheeted compound for 1 to 24 h at 23 6 3C(73.46 5.4F) and a relative humidity notgreater than 55 %. For maximum precision,condition for 1 to 24 h in a closed container toprevent absorption of
42、moisture from the air orin an area controlled at 35 6 5 % relative hu-midity.7. Test for Cure Characteristics Using the Cure Meter7.1 Measure vulcanization characteristics with an Oscillat-ing Disk cure meter in accordance with Test Method D2084 ora Rotorless Cure Meter in accordance with Test Metho
43、dD5289.7.2 The recommended standard Oscillating Disk test condi-tions are: 1.7 Hz oscillation frequency; 61 amplitude ofoscillation, 160C die temperature, 30-min test time, and nopreheating. The recommended test conditions for the RotorlessCure Meter are: 1.7 Hz oscillation frequency, 60.5 of arc fo
44、rtorsional shear cure meters and 60.05mm for linear shear curemeters, 160 C die temperature, 30 min test time, and nopreheating. Tolerances for the listed conditions are included inthe specified test methods.7.3 The recommended standard test parameters are: ML,MH, tsl,t850 and t890.8. Preparation an
45、d Testing of Vulcanizates8.1 An alternative to measuring vulcanization parameters isthe measurement of stress-strain properties of vulcanizates inaccordance with Test Methods D412. Prepare test sheets andvulcanize them in accordance with Practice D3182.8.1.1 The recommended standard vulcanization ti
46、mes forthe mill mixed compound are 20, 40, and 60 min at 150C(302F). The recommended standard vulcanization time for theminiature internal mixer compounds is 40 min at 150C.NOTE 2Vulcanization times of 25, 50, and 75 min at 145C (293F)for the mill-mixed compounds and 50 min at 145C for the MIM-mixed
47、compounds may also be used, but will not necessarily give the sameresults as the recommended standard vulcanization conditions.8.1.2 Condition all vulcanizates for 16 to 96 h at a tempera-ture of 23 6 2C (73.4 6 3.6F) prior to making stress-straintests.NOTE 3Quality control of rubber production may
48、require testingwithin 1 to6htoprovide close surveillance of plant operations; however,slightly different results may be obtained.8.1.3 Prepare test specimens and obtain tensile stress, ten-sile strength, and elongation in accordance with Test MethodsD412.9. Precision and Bias39.1 This precision and
49、bias section has been prepared inaccordance with Practice D4483. Please refer to this practicefor terminology and other statistical calculation details.9.2 The precision results in this precision and bias sectiongive an estimate of the precision of this test method with thematerials (rubbers, etc.) used in the particular interlaboratoryprogram as described below. The precision parameters shouldnot be used for acceptance or rejection testing of any group ofmaterials without documentation that the param