ASTM D7334-2008 用前进接触角法测量涂料、颜料和基质的表面润湿性的标准实施规程

作者:标准资料网 时间:2024-05-14 23:27:09  浏览:9822   来源:标准资料网

【英文标准名称】:StandardPracticeforSurfaceWettabilityofCoatings,SubstratesandPigmentsbyAdvancingContactAngleMeasurement
【原文标准名称】:用前进接触角法测量涂料、颜料和基质的表面润湿性的标准实施规程
【标准号】:ASTMD7334-2008
【标准状态】:现行
【国别】:美国
【发布日期】:2008
【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】:D01.23
【标准类型】:(Practice)
【标准水平】:()
【中文主题词】:
【英文主题词】:advancingcontactangle;contactangle;surfacetension;wettability;wetting
【摘要】:Thisstandardisusefulforcharacterizingthewettabilityofsurfaces.Asurfacethatiseasytowetisoneoverwhichacoatingismorelikelytogivegoodadhesionandappearanceandlesslikelytosuffersurfacetensionrelateddefectssuchascrawling,cratering,pinholingandorangepeel.Thisstandardalsocanbeusedtotestpigmentsurfacesforwettability,particularlybypotentialsurfactant-orresin-baseddispersantsormillbases.Easilywettedpigmentsaremorelikelytobeeasytodisperseanddispersants/millbasesthatwetpigmentsofinterestaremorelikelytodispersethosepigmentswell.Althoughthecontactangleisgovernedbythesurfacetensionsofthetestliquidandtestsurface,theanglecannotprovideasurfacetensionvaluedirectly.Alowadvancingcontactanglevalue(x003C;45x00B0;)isindicativeofwettingandanglesof10to20x00BA;areindicativeofexcellentwetting.Watercanbeusedasatestliquidtoestablish(viatheadvancingcontactangle)whetherasurfaceishydrophilic(anglex003C;45x00BA;),hydrophobic(angle>90x00BA;)orsomewherein-between(angleof45to90x00BA;).Watercontactangleshavebeenusedtoestimatesurfacecleanlinessbeforeandaftercleaningoperations,easeofwettabilityofsurfacesbywaterbornecoatingsandtheeffectivenessofrinsingprocesses.Anorganicliquidsuchasasolventalsocanbeusedtocharacterizeasubstrate,coatingorpigment.Theresultantcontactanglewilldependonthesurfacetensionsoftheliquidandthetestsurface.Alowsurfacetension(energy)testsurfacewillnotbewetbyahighsurfacetensionliquid.Inadditiontowaterandsolvents,asurfactantdispersionordispersantsolutioncanbeusedtotestapigmentsurface.Anytestliquidthatisapotentialdispersantforatestpigmentmustwetthepigmentwelloritwillnotworkasadispersant.Contactanglemeasurementscanbeusedtomapsurfacesintermsofhydrophilicity,presenceoflowsurfacetensioncomponentsorcontaminants,orvariationsincomposition.Otheranalyticalmethodssuchasinfraredmicroscopywouldbeneededtoidentifythechemicalmoietiesthatgivethecontactangledifferences.Thistestmethodcanbeusedonnearlyallcoatingsandsubstratesandmaybeextendedtopigmentsbycompressingthepigmentpowderintoasoliddisk.1.1Thispracticecoversthemeasurementoftheangleofcontactwhenadropofliquidisappliedtoacoatedsurface,substrate,orpreformeddiskofpigment.1.2Therearetwotypesofcontactangles,advancingandreceding.Thisstandarddealsonlywithadvancingcontactangles.1.3Thispracticeisintendedtosupplementthemanufacturerx2019;sinstructionsforthedevicebeingusedtomakethemeasurements,butisnotintendedtoreplacethem.1.4Acommontestliquidiswater,butmanyotherliquidssuchassolvents,surfactantanddispersantsolutionsandevenliquidpaintscanbeused.1.5Thispracticeisbasedongoniometry,whichinvolvestheobservationofasessiledropoftestliquidonasolidsubstrate.1.6Althoughcontactanglesaregovernedbysurfacetension,thisstandardcannotbeusedtomeasuresurfacetensiondirectly.1.7ThevaluesstatedinSIunitsaretoberegardedasthestandard.Thevaluesgiveninparenthesesareforinformationonly.1.8Thisstandarddoesnotpurporttoaddressallofthesafetyconcerns,ifany,associatedwithits......
【中国标准分类号】:G51
【国际标准分类号】:87_040
【页数】:3P.;A4
【正文语种】:英语