1、Designation: D 3848 03Standard Test Methods forRubberEvaluation of NBR (Acrylonitrile-ButadieneCopolymers) Mixed With Carbon Black1This standard is issued under the fixed designation D 3848; the number immediately following the designation indicates the year oforiginal adoption or, in the case of re
2、vision, the year of last revision. A number in parentheses indicates the year of last reapproval. Asuperscript epsilon (e) indicates an editorial change since the last revision or reapproval.1. Scope1.1 These test methods specify the standard materials, testformula, mixing procedures, and test metho
3、ds 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, if any, associ
4、ated 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:2D 412 Test Methods for Vulcanized Rubber and Thermo-plastic
5、 ElastomersTensionD 1646 Test Methods for RubberViscosity, Stress Relax-ation, and Pre-Vulcanization Characteristics (Mooney Vis-cometer)D 2084 Test Method for Rubber PropertyVulcanizationUsing Oscillating Disk Cure MeterD 3182 Practice for RubberMaterials, Equipment, andProcedures for Mixing Standa
6、rd Compounds and Prepar-ing Standard Vulcanized SheetsD 3896 Practice for Rubber from Synthetic SourcesSamplingD 4483 Practice for Determining Precision for Test MethodStandards in the Rubber and Carbon Black IndustriesD 5289 Test Method for Rubber PropertyVulcanizationUsing Rotorless Cure MetersD 6
7、204 Test Method for RubberMeasurement of Unvulca-nized Rheological Properties Using Rotorless Shear Rhe-ometers3. 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 research and develop-
8、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 + XAZinc oxideB3.00Sul
9、fur, 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-P is available f
10、rom 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. Weigh the masterba
11、tch 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 0.1 g, thecompound
12、ing 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. Thecompound material blend is prepared by
13、 blending a proportional mass of each1These test methods are under the jurisdiction of ASTM Committee D11 onRubber and are the direct responsibility of Subcommittee D11.23 on SyntheticRubbers.Current edition approved Nov. 1, 2003. Published December 2003. Originallyapproved in 1980. Last previous ed
14、ition approved in 2002 as D 3848 98 (2002).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 In
15、ternational, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959, United States.material 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 withPractice D 3896.6. Mi
16、xing 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 AMill Mix Procedure:6.2.1 F
17、or general mixing procedures, refer to PracticeD 3182.6.2.2 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 cutting.226.2.2.2Add sulfu
18、r 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 mill.2116.2.2.6Set the roll
19、s 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 record. If it differsfro
20、m 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 TestMethod D 1646 or rheological properties in ac-cordance with Test Method D 6204, vulcanizingcharacteristics in accordance with Test MethodD 2084, or
21、 Test Method D 5289, or both, ifthese are desired. Condition the sample for 1to24hat236 2C (73.4 6 3.6F) before test-ing.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 passing the folded stock betwe
22、en 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 notgreater than 55 %. Fo
23、r 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 D 3182. Mix with the MIM
24、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 into strips thatare appro
25、ximately 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 blendedtogether, taking care t
26、o 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.8.0 9.06.3.3.5D3848032Pa
27、ss 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.6.3.3.7Cut a sample for testing of
28、 compound viscos-ity in accordance with Test Method D 1646 orrheological properties in accordance with TestMethod D 6204, or vulcanizing characteristicsin accordance with Test Method D 2084, or TestMethod D 5289, if these are desired. Conditionthe sample 1 to 24 h at 23 6 2C (73.4 63.6F) before test
29、ing.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 a setting to give afinished g
30、age 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 thesheeted compound for 1 to
31、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 Procedure:6.4.1 For general mixing pr
32、ocedure refer to PracticeD 3182.6.4.2 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 ram.006.4.2.2Charge one half
33、 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 the batch to mix until a tempe
34、rature 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 immediately through the stan-dard labo
35、ratory 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/s (77 rpm), and raise the ram
36、.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 of110 6 5C (230 6 9F) or a total
37、 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 6 5C (104 6 9F) and set at0.
38、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 testing of compoundviscosity in
39、 accordance with Test MethodD 1646, or rheological properties in accordancewith Test Method D 6204, or vulcanizing char-acteristics in accordance with Test MethodD 2084, or Test Method D 5289, if these aredesired. Condition the sample for 1 to 24 h at23 6 3C (73.4 6 5.4F) before testing.D38480336.4.
40、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 milldirection. Cool on a flat,
41、 dry metal surface.6.4.3.9Four 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 moisture from the air orin an area c
42、ontrolled 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 D 2084 ora Rotorless Cure Meter in accordance with Test MethodD 5289.7.2 The recommended standar
43、d 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 fortorsional shear cure meters and 6
44、0.05mm 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 and Testing of Vulcanizates8.1 An al
45、ternative to measuring vulcanization parameters isthe measurement of stress-strain properties of vulcanizates inaccordance with Test Methods D 412. Prepare test sheets andvulcanize them in accordance with Practice D 3182.8.1.1 The recommended standard vulcanization times forthe mill mixed compound a
46、re 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-mixedcompounds may also be used, but
47、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 require testingwithin 1 to6htopr
48、ovide 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 MethodsD 412.9. Precision and Bias39.1 This precision and bias section has been prepared
49、inaccordance with Practice D 4483. 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 parameters are appli-cable to the particular gr
