plasticizers buffalo邻苯二甲酸酯类增塑剂的水牛课件

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1、PhthalatePlasticizersCE435IntroductiontoPolymersBrianAmatoSarahKarlCarlaNgTimeline(history)FirstPlasticizer18601930PhthalatesIntroduced1980’sDEHPDeclaredCarcinogenic2001IARCRe-classifiesDEHPasnon-carcinogenic1998EuropeanParliamentcallsforalternativestophthalatesOutlineInt

2、roductionAPlasticizerTimelineTheoryWhatarePhthalatePlasticizers(andwhydowecare)?ThePlasticizerMarketHealthConcernsScienceandIndustryResponseGovernmentPositionsHealthorHype?Conclusions.IntroductionWhatisaplasticizer?Wherearetheycommonlyfound?GeneralDefinitionAPlasticizerisa

3、polymeradditive.Effectonpolymerproperties:animportantdistinctionfromotheradditives.Increasespolymerflexibility,elongationorworkability.TypesofPlasticizer(I)Internalvs.ExternalInternalplasticizationoccursviachemicalinteractions.Copolymerizationisonetypeofinternalplasticizat

4、ion.Externalplasticizationoccursviaphysicalinteractions.Externalisthemostcommon:cost,easeofprocessing.TypesofPlasticizer(II)Primaryvs.SecondaryPrimaryPlasticizeraffectsresinproperties.Secondaryisa“Plasticizer-plasticizer”:usedtoincreasetheeffectivenessoftheprimaryplasticiz

5、er.PlasticizersInPVCCling-filmforfoodpackaging.Medicaldevices:bloodbags,IVbags,tubing.Vinylfloors.Syntheticleather.ElectricalCables.Toys:teethersforinfantsandErnie’sfavoritebath-timecompanion.PlasticizersAllAroundUsNon-PVCUsesLiquidplasticizersusedincoatingtoprotectcarchas

6、sis.Paints.PrintingInks.Adhesives.PlasticizerTheoryThreeMechanisms:LubricityTheoryGelTheoryFree-VolumeTheoryLubricityTheoryAssumestherigidityoftheresin(purepolymer)arisesfrom“intermolecularfriction.”Plasticizermoleculesareintroducedonheating.Atroomtemperature,thesemolecule

7、sactaslubricantsforthepolymerchains.GelTheoryResin-resininteractionsoccurat“centersofattachment.”Plasticizermoleculesbreaktheseinteractionsandmasksthecentersfromeachother,preventingre-formation.Thistheoryisnotsufficienttodescribeinteraction–shouldbecombinedwithLubricityThe

8、ory.Free-VolumeTheoryFreevolume:“internalspace”availableinthepolymerforthechainstomove.Th