1、Designation: D1986 14Standard Test Method forDetermining the Apparent Viscosity of Polyethylene Wax1This standard is issued under the fixed designation D1986; the number immediately following the designation indicates the year oforiginal adoption or, in the case of revision, the year of last revisio
2、n. 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 This test method describes the determination of theviscosity of polyethylene wax using small-volume, concentriccylinder, rotationa
3、l viscometer and a temperature bath at140C.1.2 The values stated in SI units are to be regarded asstandard. The units in parentheses are provided for userconvenience and are not standard.1.3 This standard does not purport to address all of thesafety concerns, if any, associated with its use. It is t
4、heresponsibility 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:2E1970 Practice for Statistical Treatment of ThermoanalyticalData3. Terminology3.1 Def
5、initions:3.1.1 polyethylene waxpolymerized ethylene with a mo-lecular weight 2,000 to 10,000 g/mol and a density of 0.9 to 1.0g/cm3. These polymers may be oxidized or copolymerized butshould have a melt point lower than 140C.3.1.2 viscositythe ratio of shear stress to shear rate. Theviscosity of a l
6、iquid is a measure of the internal friction of theliquid in motion.3.1.2.1 DiscussionThe unit of viscosity is the pascalsecond (Pas). For a Newtonian liquid, the viscosity is constantat all shear rates. For a non-Newtonian liquid, viscosity willvary depending on shear rate.3.1.3 apparent viscosityth
7、e viscosity determined by thistest method and expressed in millipascal seconds (mPas orcentipoises (cP). (1 cP=1 mPas). Its value may vary with thespindle and rotational speed selected because many waxes arenon-Newtonian.4. Significance and Use4.1 This test method is used to determine a physicalprop
8、erty of a wax and may determine the utility of the wax, aswell as being a significant quality control test.5. Apparatus5.1 Small-volume, Coaxial Rotational Viscometer3Theessential instrumentation required providing the minimal rota-tional viscometer analytical capabilities for this method in-clude:5
9、.1.1 Drive Motor, to apply an unidirectional rotationaldisplacement to the specimen at a rate of 0.05 to 6.0 rad/s (0.5to 60 r/min) constant to 61%.5.1.2 Force Sensor, to measure the torque up to 0.6 mNmdeveloped by the specimen to the rotational displacement ofthe rotational element.5.1.3 Coupling
10、Shaft, or other means to transmit the rota-tional displacement from the motor to the specimen.5.1.4 Rotational Element, Spindle or Tool, to fix the speci-men between the drive shaft and a stationary position. Acoaxial spindle with the dimensions shown in Fig. 1 is suitablefor this test method.5.1.5
11、Data Collection Device, to acquire and display mea-sured or calculated signals from the test. The minimum outputsignals required for apparent viscosity are torque, rotationalspeed, temperature and time.5.1.6 Stand, to support, level and adjust the height of thedrive motor, shaft and rotational eleme
12、nt.5.1.7 Auxiliary Instrumentation, useful in conducting thistest method includes:5.1.7.1 Data Analysis Capability, to provide viscosity, stressor other useful parameters derived from measured signals.5.1.7.2 Level, to indicate the vertical plumb of the drivemotor and shaft geometry.1This test metho
13、d is under the jurisdiction ofASTM Committee D21 on Polishesand is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edition approved Sept. 1, 2014. Published October 2014. Originallyapproved in 1991. Last previous edition approved in 2013 as D1986-13. DOI:10.1520/D1986-14.2F
14、or 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.3Available from most manufacturers of precision laboratory inst
15、ruments. Manyversions have an integral controlled temperature bath and other specified apparatus.The product literature or sales information usually specifies that the instrument issuitable for use in ASTM D1986.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA
16、19428-2959. United States15.2 Temperature Sensor, to provide an indication of thespecimen temperature over the range of 130 to 160C to within60.1C.5.3 Temperature Bath, to provide a controlled isothermaltemperature environment for the specimen.5.4 Temperature Controller, capable of operating the tem
17、-perature bath at an isothermal temperature over the range of130 to 160C, constant to within 60.5C.5.5 Small Volume Container, with Insulating Cap, with acapacity of 9 to 10 mL to hold the test specimen in thetemperature bath during testing.6. Calibration6.1 The viscometer is calibrated using Newton
18、ian fluidsprovided by the manufacturer. No zero adjustment is neededsince experience has shown that the zero point will not vary awell maintained instrument. The viscometer instrument andspindles are precision equipment that should be protected fromundue shock and mishandling. Physical damage to the
19、 instru-ment will often reveal itself as lack of pointer oscillationevenly about the zero point when the instrument is operated inair.6.2 The instrument may be further calibrated using standardreference fluids. Suitable fluids are available in nominalviscosities up to 15 Pas at 149C (300F).3A proced
20、ure forinstrument calibration using standard reference fluids should beavailable from the instrument manufacturer. Results obtainedusing standard reference fluids should not deviate from thenominal viscosity by more than 2 %.6.3 To check the temperature controller and bath, place aquantity of polyet
21、hylene wax in the sample container and allowit to melt. Insert the thermal sensor through the insulating capand fix it at a proper depth, but not in contact with the walls ofthe container. Adjust the temperature controller to provide thedesired test temperature. Rotate the sensor during temperaturer
22、eading to minimize the effect of thermal gradients in thesample. Continue temperature readings and controller adjust-ment until minimum deviation from test temperature is ob-tained. Minimum deviation may vary between laboratories,depending upon the controller, but in no case should exceed60.5C. Repe
23、at this procedure for any test temperature desiredwithin the scope of this test method.7. Procedure7.1 Preparation of SamplePlace approximately8gofsample in the sample chamber. Melt the sample in thetemperature bath preheated to 140C with the insulating cap inplace. Heat until the sample is molten a
24、nd at the test tempera-ture.NOTE 1Avoid temperatures excessively above the melt temperature orprolonged heating of the molten sample to minimize thermal and oxidativedecomposition.NOTE 2If polyethylene wax has a melt point higher than 135C, theprocedure should be run at 150C.7.2 System Alignment and
25、 Spindle InsertionWith the vis-cometer raised, connect the spindle to the motor shaft. Lowerthe leveled viscometer and insert the spindle in the samplechamber until the tip of the alignment bracket is 2 mm (116 in.)above the top of the container and in contact with the back ofthe locating index. Pla
26、ce the insulating cap on the samplechamber.7.3 Start the rotation of the spindle at the lowest rotationalspeed. When temperature of the test specimen is within60.1C of the test temperature, stop the spindle rotation,remove the cap, raise the viscometer and spindle and inspectthe liquid level on the
27、spindle shaft. The liquid should extendabout 0.6 to 1.3 cm (14 to12 in.) up the spindle shaft. If theliquid level varies significantly from this, add or removesample.7.4 Lower the spindle into the test specimen and start thespindle rotation of the spindle at the lowest rotational speedsetting. Wait
28、for the temperatures to equilibrate within 60.1Cof the test temperature.7.5 Once equilibrium is reached, select a rotational speedthat will produce a scale reading between 10 and 95 of fullscale, and preferably near the midpoint of the scale. Allow thespindle to rotate at this speed for 15 min befor
29、e engaging thepointer clutch and stopping the motor to record the scalereadings. Restart the motor, and allow at least five additionalrevolutions before taking a reading. Repeat this operation untilthree consecutive readings differ by no more than 0.5 unitsFIG. 1 Coaxial SpindleD1986 1427.6 After 15
30、 min, engage the pointer clutch, stop the rotationof the spindle, and record the scale reading.7.7 After 1 min, restart the spindle rotation at the samespeed.7.8 Repeat 7.6 and 7.7 until three consecutive readings areobtained which differ by no more than 0.5 %. Record thesethree values.8. Calculatio
31、ns8.1 Convert each of the three readings from 7.8 to viscosity,using the method described in the instrument instructionmanual.8.2 Calculate and report the mean viscosity of the threeresults of 8.1 (see Practice E1970).9. Report9.1 Report the following information with the determinedmean apparent vis
32、cosity:9.1.1 A complete description of the viscometer, includingmanufacturer, model number, spindle used, rotational speedand test temperature.10. Precision10.1 RepeatabilityDuplicate results by the same operatorand using the same viscometer shall not be considered suspectunless they differ by more
33、than 61%.10.2 ReproducibilityTo be determined.11. Bias11.1 The procedure in this test method for measuring theapparent viscosity of polyethylene wax has no bias because thevalue for the viscosity is defined only in terms of this testmethod.12. Keywords12.1 polish; polyethylene wax; viscometer; visco
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37、M Committee on Standards, at the address shown below.This standard is copyrighted by ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959,United States. Individual reprints (single or multiple copies) of this standard may be obtained by contacting ASTM at the aboveaddress or at 610-832-9585 (phone), 610-832-9555 (fax), or serviceastm.org (e-mail); or through the ASTM website(www.astm.org). Permission rights to photocopy the standard may also be secured from the Copyright Clearance Center, 222Rosewood Drive, Danvers, MA 01923, Tel: (978) 646-2600; http:/ 143
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