【英文标准名称】:Plastics-Determinationofwaterabsorption
【原文标准名称】:塑料.吸水率测定
【标准号】:BSENISO62-1999
【标准状态】:作废
【国别】:英国
【发布日期】:1999-04-15
【实施或试行日期】:1999-04-15
【发布单位】:英国标准学会(BSI)
【起草单位】:BSI
【标准类型】:()
【标准水平】:()
【中文主题词】:试样;潮气测量;含量测定;试样制备;尺寸;重量测量;数学计算;高聚物;管状;增强的材料;塑料;四方形;吸水试验;吸水率;扩散;煮沸试验;试验条件;方程
【英文主题词】:Absorption;Absorptivity;Determination;Determinationprocedures;Humidity;Moisture;Plastics;Quantityofwater;Testpieces;Testing;Tests;Water;Waterabsorption
【摘要】:1ThisInternationalStandarddescribesaprocedurefordeterminingthemoistureabsorptionpropertiesinthe"through-the-thickness"directionofflatorcurved-formsolidplastics.ThisInternationalStandardalsodescribesproceduresfordeterminingtheamountofwaterabsorbedbyplasticspecimensofdefineddimensions,whenimmersedinwaterorwhensubjectedtohumidairundercontrolledconditions.The"through-the-thickness"moisturediffusioncoefficientcanbedeterminedforsingle-phasematerialbyassumingFickiandiffusionbehaviourwithconstantmoistureabsorptionpropertiesthroughthethicknessofthetestspecimen.Thismodelisvalidforhomogeneousmaterialsandforreinforcedpolymer-matrixcompositestestedbelowtheirglasstransitiontemperature.However,sometwo-phasematricessuchashardenedepoxiesmayrequireamulti-phaseabsorptionmodelwhichisnotcoveredbythisInternationalStandard.2Ideallythebestcomparisonofthewaterabsorptionpropertiesand/ordiffusioncoefficientsofmaterialsshouldbecarriedoutonlyusingtheequilibriummoisturecontentofplasticsexposedtoidenticalconditions.Thecomparisonofmaterialsusingpropertiesatmoistureequilibriumdoesnotassume,andisthereforenotlimitedto,single-phaseFickiandiffusionbehaviour.3Alternatively,waterabsorptionofplasticspecimensofdefineddimensionsexposedtoimmersionorhumidityundercontrolledconditionsbutforanarbitrarytimeperiodcanbeusedtocomparedifferentbatchesofthesamematerialorforqualitycontroltestsofagivenmaterial.Forthistypeofcomparison,itisessentialthatalltestspecimensbeofidenticaldimensionsand,asnearlyaspossible,havethesamephysicalattributes,e.g.surfacesmoothness,internalstresses,etc.However,moistureequilibriumisnotreachedundertheseconditions.Therefore,resultsfromthistypeoftestcannotbeusedtocomparethewaterabsorptionpropertiesofdifferenttypesofplastics.Forthemorereliableresults,simultaneoustestsarerecommended.4TheresultsobtainedusingthemethodsdescribedinthisInternationalStandardareapplicabletomostplasticsbutarenotapplicabletocellularplastics,granulates,orpowderswhichcanshowadditionalabsorptionandcapillaryeffects.Plasticsexposedtomoistureundercontrolledconditionsfordefinedperiodsoftimeproviderelativecomparisonsbetweenthem.Thetestsdescribedfordeterminationofdiffusioncoefficientmaynotbeapplicabletoallplastics.Plasticsthatcannotretaintheirshapewhenimmersedinboilingwatershouldnotbecomparedusingmethod2in6.3.
【中国标准分类号】:G31
【国际标准分类号】:83_080_01
【页数】:22P;A4
【正文语种】:英语