ASTM_D_4878_-_15.pdf

Designation:D487815Standard Test Methods forPolyurethane Raw Materials:Determination of Viscosity ofPolyols1This standard is issued under the fixed designation D4878;the number immediately following the designation indicates the year oforiginal adoption or,in 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.Scope*1.1 These test methods(Aand B)determine the viscosity ofpolyols in the range from 10 to 100 000 mPas(cP)at 25C.Test Method A is a rotational procedure for determiningdynamic viscosity.Test Method B is a general procedure forkinematic viscosity of transparent polyols.(See Note 1.)1.2 The values stated in SI units are to be regarded as thestandard.Other equivalent units are provided because ofcurrent common usage.1.3 This standard does not purport to address all of thesafety concerns,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.NOTE1Test Method A is equivalent to ISO 3219.Test Method B isequivalent to ISO 3104.2.Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(and Calculation of Dynamic Viscos-ity)D446 Specifications and Operating Instructions for GlassCapillary Kinematic ViscometersD883 Terminology Relating to PlasticsE2251 Specification for Liquid-in-Glass ASTM Thermom-eters with Low-Hazard Precision Liquids2.2 ISO Standards:3ISO 3104 Petroleum ProductsTransparent and OpaqueLiquidsDetermination of Kinematic Viscosity and Cal-culation of Dynamic ViscosityISO 3219 PlasticsPolymers/Resins in the Liquid State ofas Emulsions or DispersionsDetermination of ViscosityUsing a Rotational Viscometer with Defined Shear Rate3.Terminology3.1 For definitions of terms used in these test methods seeTerminology D883.4.Significance and Use4.1 These test methods are suitable for research or as qualitycontrol or specification tests.4.2 Viscosity measures the resistance of a fluid to uniformlycontinuous flow without turbulence or other forces.5.Sampling5.1 Polyester and polyether polyols contain molecules cov-ering an appreciable range of molecular weights.These canfractionate during solidification.Unless the material is a finelyground solid it is necessary to melt(using no higher tempera-ture than necessary)and mix the polyol well before removinga sample for analysis.Many polyols are hygroscopic and careshould be taken to provide minimum exposure to atmosphericmoisture during the sampling.TEST METHOD AROTATIONAL VISCOSITY6.Summary of Test Method6.1 The viscosity is measured by determining the torque ona spindle rotating at constant speed in the liquid sample at25 6 0.1C.Generation of comparative data using this methodrequires agreement on the speed,spindle,temperature,time ofrotation,and torque range of the instrument used.7.Apparatus7.1 Constant-Temperature Bath,capable of maintaining atemperature of 25 6 0.1C is to be used.Water,water andglycerin,or oil is used as the heating medium and the bath isto be provided with heating,circulating,and thermostattingdevices.7.2 Bath and Sample Thermometers,graduated in 0.1Csubdivisions and standardized for the range of use to the1These test methods are under the jurisdiction of ASTM Committee D20 onPlastics and is the direct responsibility of Subcommittee D20.22 on CellularMaterials-Plastics and Elastomers.Current edition approved May 1,2015.Published June 2015.Originallyapproved in 1988.Last previous edition approved in 2008 as D4878-08.DOI:10.1520/D4878-15.2For 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.3Available from American National Standards Institute(ANSI),25 W.43rd St.,4th Floor,New York,NY 10036,http:/www.ansi.org.*A Summary of Changes section appears at the end of this standardCopyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 nearest 0.01C.ASTM Saybolt Viscosity Thermometers hav-ing ranges from 19 to 27C and 49 to 57C,as specified,andconforming to the requirements for Thermometers S117C andS64C,respectively,as prescribed in Specification E2251 arerecommended.Any other thermometric device of equal orbetter accuracy is also acceptable.7.3 Rotational ViscometerCapable of user defined speedand spindle combinations.An instrument that is capable ofproviding the shear rate is recommended.The calibration of theinstrument is to be checked periodically by measuring theviscosity of NIST traceable standard fluids.8.Solvent8.1 Cleaning Solventmethanol or acetone,reagent grade.Any solvent in which the polyol is completely miscible isacceptable.9.Preparation of Sampl