1、Designation:D488915Standard Test Methods forPolyurethane Raw Materials:Determination of Viscosity ofCrude or Modified Isocyanates1This standard is issued under the fixed designation D4889;the number immediately following the designation indicates the year oforiginal adoption or,in the case of revisi
2、on,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 ofcrude or modified isocyanates.They are applicable to pr
3、oductsderivedfromtoluenediisocyanate,methylenedi(phenylisocyanate),and polymeric(methylene phenylisocya-nate)(see Note 1).NOTE1Test method A includes a procedure for measuring dynamicviscosity using a rotational instrument.Test method B is simply areference to a general procedure for measuring kinem
4、atic viscosity,D445.1.2 The values stated in SI units are to be regarded asstandard.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 de
5、termine the applica-bility of regulatory limitations prior to use.For specific hazardsstatement,see Warning at the end of 5.1.NOTE2This standard is equivalent to ISO 3219 and ISO 3104.2.Referenced Documents2.1 ASTM Standards:2D445 Test Method for Kinematic Viscosity of Transparentand Opaque Liquids(
6、and Calculation of Dynamic Viscos-ity)D883 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 D
7、ynamic ViscosityISO 3219 PlasticsPolymers/Resins in the Liquid State oras Emulsions or DispersionsDetermination of ViscosityUsing a Rotational Viscometer with Defined Shear Rate3.Terminology3.1 DefinitionsFor definitions of terms used in these testmethods see Terminology D883.4.Significance and Use4
8、.1 These test methods can be used for research,qualitycontrol,or specification tests to characterize isocyanates usedin polyurethane products.4.2 Viscosity measures the resistance of a fluid to uniformcontinuous flow without turbulence or other forces.4.3 Some isocyanates exhibit non-Newtonian behav
9、ior un-der certain conditions.Whenever possible,generate results forcomparison under the same conditions,that is,the samespindle/speed combination for rotational viscosity and thesame tube size for kinematic viscosity.5.Sampling5.1 Since organic isocyanates react with atmosphericmoisture,take specia
10、l precautions in sampling.Usual samplingmethods,even when conducted rapidly,can cause contamina-tion of the sample with insoluble urea.Therefore,blanket thesample with dry air or nitrogen at all times.(WarningDiisocyanates are eye,skin and respiratory irritants at concen-trations above the occupatio
11、nal exposure limit(TLV or PEL).Diisocyanates can cause skin and respiratory sensitization(asthma)in some people.Once sensitized,it is essential to limitfurther exposure to diisocyanates.Use a combination ofengineering controls and personal protective equipment,in-cluding respiratory,skin and eye pro
12、tection,to prevent over-exposure to diisocyanates.Consult the product suppliersSafety Data Sheet(SDS)for more detailed information aboutpotential health effects and other specific safety and handlinginstructions for the product.)6.Test Conditions6.1 Since isocyanates react with moisture,keep laborat
13、oryhumidity low,preferably about 50%relative humidity.SeeWarning in 5.1.1These test methods are under the jurisdiction of ASTM Committee D20 onPlastics and are the direct responsibility of Subcommittee D20.22 on CellularMaterials-Plastics and Elastomers.Current edition approved May 1,2015.Published
14、March 2011.Originallyapproved in 1988.Last previous edition approved in 2011 as D4889-04(2011).DOI:10.1520/D4889-15.2For 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 s
15、tandards 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,W
16、est Conshohocken,PA 19428-2959.United States1 TEST METHOD AROTATIONAL VISCOSITY7.Summary of Test Method7.1 The viscosity is measured by determining the torque ona spindle rotating at constant speed in the liquid sample whichis adjusted to 25 6 0.1C.Generation of comparative datausing this method requires agreement on the speed,spindle,temperature,time of rotation and torque range of the instru-ment used.8.Apparatus8.1 Constant-Temperature Bath,capable of maintaining atemperature of 25 6 0.1C is
