ASTM_D_2857_-_95_2007.pdf

Designation:D285795(Reapproved 2007)Standard Practice forDilute Solution Viscosity of Polymers1This standard is issued under the fixed designation D2857;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.Scope1.1 This practice covers the determination of the dilutesolution viscosity of polymers.There are several ASTMstandards(Test Methods D789,D1243,D1601,and D4603,and Practice D3591)that describe dilute solution viscosityprocedures for specific polymers,such as nylon,poly(vinylchloride),polyethylene,and poly(ethylene terephthalate).Thispractice is written to augment these standards when problemsarise with which the specific procedure is not concerned,orwhen no standard is available for the polymer under investi-gation.1.2 This practice is applicable to all polymers that dissolvecompletely without chemical reaction or degradation to formsolutions that are stable with time at a temperature betweenambient and 150C.Results are usually expressed as relativeviscosity(viscosity ratio),inherent viscosity(logarithmic vis-cosity number),or intrinsic viscosity(limiting viscosity num-ber)(see 3.1).1.3 For polyamides,relative viscosity values by this proce-dure are not equivalent to those determined by Test MethodsD789.1.4 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.NOTE1This standard and ISO 1628,“PlasticsDetermination ofViscosity Number and Limiting Viscosity Number,”are technicallyequivalent.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 ViscometersD789 Test Methods for Determination of Solution Viscosi-ties of Polyamide(PA)D883 Terminology Relating to PlasticsD1243 Test Method for Dilute Solution Viscosity of VinylChloride PolymersD1600 Terminology forAbbreviated Terms Relating to Plas-ticsD1601 Test Method for Dilute Solution Viscosity of Ethyl-ene PolymersD3591 Test Method for Determining Logarithmic ViscosityNumber of Poly(Vinyl Chloride)(PVC)in FormulatedCompoundsD4603 Test Method for Determining Inherent Viscosity ofPoly(Ethylene Terephthalate)(PET)by Glass CapillaryViscometerD5226 Practice for Dissolving Polymer MaterialsE1 Specification for ASTM Liquid-in-Glass Thermometers2.2 ISO Standard:1628/1 Guidelines for the Standardization of Methods forthe Determination of Viscosity Number and LimitingViscosity Number of Polymers in Dilute Solution32.3 National Institute of Standards and Technology Docu-ment:Circular No.C602 Testing of Glass Volumetric Apparatus43.Terminology3.1 Definitions:3.1.1 Terms and definitions in Terminology D883 and ab-breviations in Terminology D1600 are applicable to thispractice.The following definitions5are applicable to thispractice.3.1.2 inherent viscosity,inh,nthe ratio of the naturallogarithm of the relative viscosity to the mass concentration ofthe polymer,c:inh=(ln r)/c.1This practice is under the jurisdiction ofASTM Committee D20 on Plastics andis the direct responsibility of Subcommittee D20.70 on Analytical Methods.Current edition approved Sept.1,2007.Published November 2007.Originallyapproved in 1970.Last previous edition approved in 2001 as D2857-95(2001).DOI:10.1520/D2857-95R07.2For 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.4Available from National Institute of Standards and Technology(NIST),100Bureau Dr.,Stop 1070,Gaithersburg,MD 20899-1070,http:/www.nist.gov.5International Union of Pure and Applied Chemistry,Compendium of Macro-molecular Nomenclature,Blackwell Scientific Publications,Oxford,England,1991.Copyright ASTM International,100 Barr Harbor Drive,PO Box C700,West Conshohocken,PA 19428-2959.United States1 3.1.2.1 DiscussionAlso known as the logarithmic viscos-ity number,ln.See also 3.1.4.3.1.3 intrinsic viscosity,nthe limiting value of thereduced viscosity or the inherent viscosity at infinite dilution ofthe polymer:#5c0limi/c!5c0liminh.3.1.3.1 DiscussionAlso known as the limiting viscositynumber and in the literature as the Staudinger index.See also3.1.4.3.1.4 reduced viscosity,nthe ratio of the relative viscosityincrement to the mass concentration of the polymer,c,that is,i/c.3.1.4.1 DiscussionAlso known as the vis