ASTM_D_4875_-_11.pdf

Designation:D487511Standard Test Methods ofPolyurethane Raw Materials:Determination of thePolymerized Ethylene Oxide Content of Polyether Polyols1This standard is issued under the fixed designation D4875;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 Test Method AProton Nuclear Magnetic ResonanceSpectroscopy(1H NMR)measures polymerized ethylene oxide(EO)in ethylene oxide-propylene oxide polyethers used inflexible urethane foams and nonfoams.It is suitable for diolsmade from the commonly used initiators and containing EOpercentages above five.For triols initiated with glycerin andtrimethylol propane,an uncorrected EO value is obtained sinceboth initiators have protons that contribute to the EO measure-ment.1.2 Test Method BCarbon-13 Nuclear Magnetic Reso-nance Spectroscopy(13C NMR)measures the polymerized EOcontent of ethylene oxide-propylene oxide polyethers used inflexible urethane foams and nonfoams.It is suitable for diolsand triols made from the commonly used initiators andcontaining EO percentages above five.1.3 The values stated in SI units are to be regarded asstandard.No other units of measurement are included in thisstandard.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.NOTE1There is no known ISO equivalent to this standard.2.Referenced Documents2.1 ASTM Standards:2D883 Terminology Relating to PlasticsE386 Practice for Data Presentation Relating to High-Resolution Nuclear Magnetic Resonance(NMR)Spec-troscopyE691 Practice for Conducting an Interlaboratory Study toDetermine the Precision of a Test Method3.Terminology3.1 DefinitionsTerminology in these test methods followsthe standard terminology defined in Terminology D883 andPractice E386.3.2 Definitions of Terms Specific to This Standard:3.2.1 heteric polyol,na polyether polyol in which ethyl-ene oxide and propylene oxide units are randomly arranged.3.2.2 initiator,na substance with which ethylene oxide orpropylene oxide reacts to form a polyether polyol.3.2.2.1 DiscussionOne initiator unit is incorporated intoeach polymer or oligomer molecule.3.2.3 EO capped polyola polyol that contains a terminalblock of ethylene oxide units4.Summary of Test Methods4.1 Test Method AThe1H NMR spectra of polyetherpolyols show two groups of resonance peaks corresponding tothe methyl protons of propylene oxide(PO)and to themethylene and methine protons of EO and PO.The EO peakarea is obtained by subtracting the area of the PO methyl peaksfrom the area of the methylene and methine peaks.Initiatorsother than glycols of EO and PO give systematic errors(seeNote 2).NOTE2The initiator error can be estimated by calculating thetheoretical contribution of initiator protons to the EO and PO peak areas.4.2 Test Method BThe13C NMR spectra of polyetherpolyols contain multiple resonances arising from initiator,EO,PO,EO/PO,sequencing,and end-group distribution.EO con-tent can be determined relative to PO or relative to PO and triolinitiator.In the former,the area of the EO peaks is ratioed to thetotal area of PO methylene and methine carbons.In the latter,the area of the EO peaks is ratioed to the total area of POmethylene and methine carbons and two initiator carbons.Thistest method describes the determination of EO relative to POonly.1These 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 April 1,2011.Published April 2011.Originallyapproved in 1988.Last previous edition approved in 2005 as D4875-05.DOI:10.1520/D4875-11.2For 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.*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 5.Significance and Use5.1 Measurements of EO content correlate with polyolreactivity(as related to primary hydroxyl content),linearity offoam rise,and the hydrophilicity of the polyol and finalproduct.5.2 Statistical data suggest that the13C NMR test method isthe preferred method for measuring low levels(less than 10%)of polymerized EO in polyols.5.3 The1H and13C NMR test methods give different resultswhich are highly correlated.The equation of the linear regres-sion is:%EOproton5 1.031%EOcarbon213!10.883(1)The standard deviation of