Additives助剂

AdditivesTrainingCourse助剂培训课程Presentedby:ProcessEngineeringTeam主讲：工艺工程BeckersAdditivesFunction助剂作用•Modifypaintorfilmpropertiesorbehavior.改变油漆漆膜特性；•Normallyusedatlowlevels.正常情况下用量低；•Manydifferenttypesavailable,alsomanydifferentproductswithinatype.很多种类型的助剂，同一类型有很多不同的产品（如流平剂）•Oftenhelponeproperty,buthurtanother.常帮助改良一个特性，但伤害到另一个特性。•Mostimportantpartofformulationyetisthemostdifficult.•最重要的配方部份也是最困难的；BeckersTypesofAdditives助剂的类型•Surfactants表面活性剂•Pigmentdispersants颜料分散剂•Rheologymodifiers触变助剂•Defoamers/antifoams消泡剂•Corrosioninhibitors防腐蚀剂•Adhesionimprovers附着力增进剂•Photostabilizers光引发剂•Flattingagents平整剂BeckersTypes,continued助剂类型（继续）•Driers干燥剂•Anti-skinningagentsandantioxidants防起皮剂和抗氧化剂•Slipaids滑爽剂•Antistaticagentsandconductivityadditives抗静电助剂和导电助剂•Flameretardants阻燃剂•Intumescentagents(improvefireresistance)膨胀剂•Biocides生物助剂（防霉、防腐和杀菌）BeckersSurfactants表面活性剂•Surface-activeagents表面活性剂•Havegroupsofoppositepolarityorsolubilityonthesamemolecule有相反极性的基团或可溶性体现在相同的分子结构。•Theyareclassifiedbasedonthechargeonthepolarheadgroup:-Anionics~~~~~~~~(-)阴离子-Cationics~~~~~~~~(+)阳离子-Nonionics~~~~~~~~~()非离子-Zwitterionics~~~,~~~~(+)(-)BeckersSurfactants•Widerangeofchemistries,structures,andproperties•Somepolymersactassurfactants•AfewsurfactantswillreactintothefilmduetoOHgroups,doublebonds,etc.•WiderangeofapplicationsSurfactantApplications•Paintsurfacemodification•Wettingandsolubilization•Emulsification•Dispersing•Foaminganddefoaming•ConductivityandantistaticadditivesPaintSurfaceModification•Usesurfactantsandsurfactant-likeoligomersandpolymerstoreducesurfacetensionandmakesurfacemorehomogeneous(theadditiveconcentratesatthesurface).•Theseadditivescanimproveflowandleveling,increasecraterresistance,andpreventorreduceotherdefectssuchasdewetting,Bénardcells,floating,etc.PaintSurfaceModifiers:Silicones硅油类•Byk-300series(300,301,302,etc.)-reduces.t.,improveleveling-polyethermodifieddimethylsiloxanecopolymers.Byk-306hasbeenaffectiveatreducingcraters,buthasalsocausedthem.•DC-200-siliconeoil•Problemswithsilicones-cancausecraters,difficulttoimpossibletorecoat(Byk-320probablyisthemostrecoatable).DifferentKindofModifiers:VariousAcrylics•PBA-Polybutylacrylate•Modaflow-poly(EA/EHA)•Multiflow-poly(EA/EHA)•Byk-358Thesematerialscometothesurface,buttheyonlyreducesolidsurfacetensionslightlyornotatall.PigmentDispersion颜料分散•Wetting湿润•Deagglomeration解聚•Stabilization稳定PigmentDispersants•Surfactants-wettingagents-dispersants•Dispersingresins•Otheradditives-amines-solventsWettingandSolubilization•Detergents-solubilizersandcleaningagents-linearstructurewithhydrophilicgroupatoneend.Example=sodiumlaurylsulfate(Tide).•Wettingagents-improvepigmentwetting,givebetterwettingofsubstratesurfaces,andmaywetcontaminantsandpreventdefects-tendtohaveahydrophilicgroupbetweentwohydrophobicchains.Examples=sodiumdioctylsulfosuccinateandSurfynol104.Emulsification•Emulsionpolymerization-oftenusedetergents.•Dispersionandemulsificationofcomponentsinwaterbornecoatings-wettingagentsandlowsurfacetensionsolventshelpdispersematerialsandpreventthemfromcausingcrateringorotherproblems.RheologyModifiers•Thixotropes(providestructure)-silicas-microgels-bentones•“Flowcontrol”agents(oftenarepolymericsurfactants)•Wettingagents•SolventsDefoamers/Antifoams•Oftencombinesurfactantwithfineparticles(siliconeandsilica,forexample).•Manyavailable.•Useatverylowlevels.•Usuallyverysystemdependent.•Cancausecratersiftoomuchisadded.•Mostsurfactantscausefoam,afew(especiallytheSurfynols)preventfoam.Anti-PopAdditives•Polystearylmethacrylates(exampleOX-60)•HighMWlatex•Silica•Wethinkthatmanysuchadditivesactlikeboilingchipsandallowvolatilestocomeoffbeforethefilmsetsup.CorrosionInhibitors•Chromates(beingphasedout)andotheroxidizers-passivatesurface(givelayerofstableoxide,protectfromfurtheroxidation).StilluseSrCrO4inrepair(touch-up)primersandtheprimerusedatLagoAlbertoinMexico(noe-coattank).•Phosphates,metaborates,phosphosilicates,borosilicates.AdhesionImprovers•Hydrogenbondingimprovesadhesiontometal:hydroxyls,carboxyls,aminegroups.•Epoxyresinshavehydroxylandethergroups-bondtosteelandinteractwithothermoleculesinthecoating.•Somesurfaces,especiallyplastics,aredifficulttoadheretobecausetheyhavelowsurfacetensionsandfewornopolargroups.Tiecoatoradhesionpromotorisnecessary-usuallythinlayerofchlorinatedpolyolefinorchlorinatedrubber.Photostabilizers•UVabsorbers•Excitedstatequenchers•Antioxidants•Hinderedaminelightstabilizers•Pigments(especiallytoprotectlowerlayers).Onereasonwhygoodhidingbybasecoatsissoimportant.BigProblemwithPhotostabilizers•Theydonotstaywherewewantthem!•Fordresearchshowsthattheyoftenmigratetothebasecoatonapplicationandbakingand/ordiffuseoutoftheclearonweathering.Thedegreeofretentiondependsonthechemistryoftheclearcoat.FlattingAgents•Addedtoreducegloss,improvesandability.•Usuallysilicaorsomeotherparticulates,althoughE.D.usesanorganicflattingagent.•Autocompanieswantashighaglossaspossible,sorarelyneededinautomotivetopcoatsorevenprimers.Driers•Driersareorganometaliccatalysts.•Theyaccelerateoxidativecrosslinkingofdryingoils(suchas