ASTM D5296-2005 用高效粒度排除色谱法测定聚苯乙烯平均分子量和分子量分布的标准试验方法

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【英文标准名称】:StandardTestMethodforMolecularWeightAveragesandMolecularWeightDistributionofPolystyrenebyHighPerformanceSize-ExclusionChromatography
【原文标准名称】:用高效粒度排除色谱法测定聚苯乙烯平均分子量和分子量分布的标准试验方法
【标准号】:ASTMD5296-2005
【标准状态】:现行
【国别】:
【发布日期】:2005
【实施或试行日期】:
【发布单位】:美国材料与试验协会(US-ASTM)
【起草单位】:D20.70
【标准类型】:(TestMethod)
【标准水平】:()
【中文主题词】:试验;塑料;聚苯乙烯
【英文主题词】:high-performancesizeexclusionchromatography(HPSEC);molecularweightaverage;molecularweightdistribution;polystyrene
【摘要】:GeneralUtility8212;Themolecularweight(MW)andmolecularweightdistribution(MWD)arefundamentalcharacteristicsofapolymersample.Theymaybeusedforawidevarietyofcorrelationsforfundamentalstudies,processing,orproductapplications.Forexample,theobservedMWDmaybecomparedtoonepredictedfromassumedkineticsormechanismsforapolymerizationreaction.Differencesbetweenthevalueswillallowalterationoftheoryorexperimentaldesign.Similarly,thestrength,meltflow,andotherpropertiesofapolymersamplemaybedependentonMWandMWD.DeterminationsofMWandMWDareusedforqualitycontrolofpolymers.Limitations8212;Becauseoftheneedforspecificcalibrationofthepolymertypeunderstudy,andbecauseofthespecificnatureofpolymer/solvent/column-packinginteractions,thistestmethodisvalidonlyforpolystyreneandnon-exclusioneffectsaretobeavoided.However,manyoftheprinciplesofthemethodmaybeappliedingeneratingHPSECmethodsforotherpolymersystems,forexample,usingtheprinciplesofuniversalcalibration.(seePracticeD3016).1.1Thistestmethodcoversthedeterminationofmolecularweight(MW)averagesandthedistributionofmolecularweightsforlinear,solublepolystyrenebyliquidhigh-performancesize-exclusionchromatography(HPSEC).Thistestmethodisnotabsoluteandrequirestheuseofcommerciallyavailablenarrowmolecularweightdistribution(MWD)polystyrenestandardsforcalibration.Thistestmethodisapplicableforsamplescontainingmolecularweightcomponentsthathaveelutionvolumesfallingwithintheelutionvolumerangedefinedbypolystyrenestandards(thatis,molecularweightsgenerallyfrom2000to2000000gmol1).1.2TheHPSECisdifferentiatedfromtraditionalsize-exclusionchromatographySEC(alsoreferredtoasgelpermeationchromatography(GPC))inthatthenumberoftheoreticalplatespermetrewithanHPSECsystemisabouttentimesgreaterthanthatfortraditionalSEC(seeTerminologyD883andPracticeD3016).TheHPSECsystemsemploylow-volumeliquidchromatographycomponentsandcolumnspackedwithrelativelysmall(generally3to20m)microporousparticles.High-performanceliquidchromatographyinstrumentationandautomateddatahandlingsystemsfordataacquisitionandprocessingarerequired.1.3ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithitsuse.Itistheresponsibilityoftheuserofthisstandardtoestablishappropriatesafetyandhealthpracticesanddeterminetheapplicabilityofregulatorylimitationspriortouse.SpecificprecautionarystatementsaregiveninSection.Note1ThereisnosimilarorequivalentISOstandard.
【中国标准分类号】:G31
【国际标准分类号】:83_080_20
【页数】:13P.;A4
【正文语种】:


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【英文标准名称】:Presstools.Rectangularretainersandpercussionplateforflangedpunches.Topfixing.
【原文标准名称】:冲压工具.带凸缘冲头的矩形挡板和冲击护板.顶部安装
【标准号】:NFE63-113-1990
【标准状态】:作废
【国别】:法国
【发布日期】:1990-10-01
【实施或试行日期】:1990-10-05
【发布单位】:法国标准化协会(AFNOR)
【起草单位】:
【标准类型】:()
【标准水平】:()
【中文主题词】:名称与符号;环形穿孔器;压力机;刀具夹持装置;表(数据);工具夹;凸模夹持器;尺寸;长方形
【英文主题词】:
【摘要】:
【中国标准分类号】:J62;J46
【国际标准分类号】:25_120_10
【页数】:7P;A4
【正文语种】:其他


MIL-A-8243D, MILITARY SPECIFICATION ANTI-ICING AND DEICING-DEFROSTING FLUIDS (26 OCT 1985)., This specification covers the requirements for two types of anti-icing and deicing-defrosting fluids for use on aircraft.