1、Designation: D1986 91 (Reapproved 2012)D1986 13Standard 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
2、, 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 This test method covers the determination of the viscosity in centipoise of polyethylene wax using the B
3、rookfield LVT orLVF viscometer and thermosel system.1.2 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibilityof the user of this standard to establish appropriate safety and health practices and determine the applicability of
4、regulatorylimitations prior to use.2. Referenced Documents2.1 ASTM Standards:2E1E2251 Specification for ASTM Liquid-in-Glass ThermometersLiquid-in-Glass ASTM Thermometers with Low-HazardPrecision Liquids3. Terminology3.1 Definitions:3.1.1 polyethylene waxpolymerized ethylene with a molecular weight
5、2,000 to 10,000 and a density of 0.9 to 1.0 g/cm3. Thesepolymers can be oxidized or copolymerized but should have a melt point lower than 140C.3.1.2 viscositythe ratio of shear stress to shear rate. The viscosity of a liquid is a measure of the internal friction of the liquidin motion. The units of
6、viscosity is the pascal second. For a Newtonian liquid, the viscosity is constant at all shear rates. For anon-Newtonian liquid, viscosity will vary depending on shear rate.3.1.3 apparent viscositythe viscosity determined by this test method and expressed in millipascal seconds. Its value may varywi
7、th the spindle and rotational speed selected because many waxes are non-Newtonian.4. Significance and Use4.1 This test method is used to determine a physical property of a wax and may determine the utility of the wax, as well as beinga significant quality control test.5. Apparatus5.1 Brookfield Ther
8、mosel System, with LVT, LVF, or LVD 111 viscometer and SC 4-31 spindle.36. Calibration6.1 The viscometer is precalibrated using Newtonian fluids provided by the manufacturer. No zero adjustment is provided sinceexperience has shown that the zero point will not vary due to changes in the spring. The
9、viscometer and spindles are precisionequipment and should be kept from undue shock and mishandling. Physical damage to the instrument will often reveal itself aserratic or no oscillation of the pointer when the instrument, with or without the spindle in place, is operated in air. When operatingnorma
10、lly, the pointer will be stable and have free oscillation about the zero point in air.1 This test method is under the jurisdiction of ASTM Committee D21 on Polishes and is the direct responsibility of Subcommittee D21.02 on Raw Materials.Current edition approved Oct. 1, 2012Oct. 1, 2013. Published O
11、ctober 2012 October 2013. Originally approved in 1991. Last previous edition approved in 20072012 asD1986-91(2007).D1986-91(2012). DOI: 10.1520/D1986-91R12.10.1520/D1986-13.2 For referencedASTM standards, visit theASTM website, www.astm.org, or contactASTM Customer Service at serviceastm.org. For An
12、nual Book of ASTM Standardsvolume information, refer to the standards Document Summary page on the ASTM website.3 Available from Brookfield Engineering Laboratories, Inc. 11 Commerce Boulevard, Middleboro, MA 02346.This document is not an ASTM standard and is intended only to provide the user of an
13、ASTM standard an indication of what changes have been made to the previous version. Becauseit may not be technically possible to adequately depict all changes accurately, ASTM recommends that users consult prior editions as appropriate. In all cases only the current versionof the standard as publish
14、ed by ASTM is to be considered the official document.Copyright ASTM International, 100 Barr Harbor Drive, PO Box C700, West Conshohocken, PA 19428-2959. United States16.2 The instrument may be further calibrated using standard reference fluids. Suitable fluids are available in nominal viscositiesup
15、to 15 000 mPas at 149C (300F).3 The procedure for instrument calibration using standard reference fluids is not encompassedby this test method. Results obtained using standard reference fluids should not deviate from the nominal viscosity by more than2 %.6.3 The temperature controller of the type re
16、commended for this procedure is factory calibrated and has control capability of60.5 % of the control point (61.0C at 175C). To further check the controller and further establish controller settings, use thefollowing procedure. Place a sufficient quantity of polyethylene wax in the sample container
17、to permit immersion of the appropriateASTM thermometer to the proper depth. Do not permit the thermometer bulb to rest on the bottom of the sample container. Suitablethermometers are shown in Specification E1E2251.6.4 Insert the thermometer through the insulating cover of the sample container and ho
18、ld it in place at the point required forproper immersion depth. Adjust the thermal controller to provide the desired test temperature. Rotate the thermometer duringtemperature reading to minimize the effect of thermal gradients in the sample. Continue temperature readings and controlleradjustment un
19、til minimum deviation from test temperature is obtained. Minimum deviation may vary between laboratories,depending upon the controller, but should in no case exceed 60.5C (0.9F). Repeat this procedure for any test temperature desiredwithin the scope of this procedure.7. Procedure7.1 Use spindle numb
20、er 31 for this test.7.2 Preparation of SamplePlace 8 g or approximately 10 mL of sample in the sample chamber. Melt the sample in thethermo-container preheated and set at 140C. If polyethylene wax has a melt point higher than 135C, the procedure should berun at 150C. Heat for 15 min with insulating
21、cap on sample chamber. Avoid excessive or prolonged heating of the sample tominimize thermal and oxidative effects.7.3 System Alignment and Spindle InsertionWith the viscometer raised, connect the spindle to the coupling nut (note left-handthread). Lower the leveled viscometer and insert the spindle
22、 in the sample chamber until the tips of the alignment bracket is 2 mm(116 in.) above the top of the thermo container and in contact with the back of the locating ring. Place insulating cap over the samplechamber.7.4 Turn on viscometer at the lowest RPM setting. When temperature equilibrium is indic
23、ated, turn off viscometer, remove thecap, raise the viscometer and spindle and inspect the liquid level on the spindle shaft. The liquid should extend about 0.6 to 1.3cm (14 to 12 in.) up the spindle shaft. If the liquid level varies significantly from this, add or remove sample.7.5 Lower viscometer
24、 and spindle and turn it on at the lowest RPM setting and wait for the temperatures to reach equilibrium.After equilibrium is reached, select a spindle speed (RPM), that will produce a scale reading nearest the midpoint of the scalebetween 10 to 95 unit range. Allow the spindle to rotate at this spe
25、ed for 15 min before engaging the pointer clutch and stoppingthe motor to record the scale readings. Restart the motor, and allow at least five additional revolutions before taking a reading.Repeat this operation until three consecutive readings differ by no more than 0.5 units.8. Calculations8.1 Co
26、nvert the average of these three readings to millipascal seconds, by multiplying this value by the appropriate factor takenfrom instrument instruction manual.9. Report9.1 Report the following information:9.1.1 Report the apparent viscosity at a given temperature along with the particulars of the ins
27、trument model, the spindle numberand rotational speed.9.1.2 Conversion:One pascal second Pas!51000 cP (1)One millipascal second mPas!51cP (2)10. Precision and Bias10.1 PrecisionDuplicate results by the same operator and using the same model (LVT or LVF) viscometer shall not beconsidered suspect unle
28、ss they differ by more than 60.3 non-convert reading (95 % confidence limits for average). (This precisionstatement will be expanded in the future.)10.2 BiasThe procedure in this test method for measuring the apparent viscosity of polyethylene wax has no bias because thevalue for the viscosity is de
29、fined only in terms of this test method.D1986 13211. Keywords11.1 Brookfield viscometer; polish; polyethylene wax; thermosel; viscosity; waxASTM International takes no position respecting the validity of any patent rights asserted in connection with any item mentionedin this standard. Users of this
30、standard are expressly advised that determination of the validity of any such patent rights, and the riskof infringement of such rights, are entirely their own responsibility.This standard is subject to revision at any time by the responsible technical committee and must be reviewed every five years
31、 andif not revised, either reapproved or withdrawn.Your comments are invited either for revision of this standard or for additional standardsand should be addressed to ASTM International Headquarters. Your comments will receive careful consideration at a meeting of theresponsible technical committee
32、, which you may attend. If you feel that your comments have not received a fair hearing you shouldmake your views known to the ASTM 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 19428-2
33、959,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 ASTM website (www.astm.org/COPYRIGHT/).D1986 133
