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PPT coursewareforHigh MaterialProfessionalEngl•Overview ofPolymer Materials•The ChemicalBasis ofPolymerMaterials•The physical properties of polymermaterials•Processing andForming ofPolymerMaterials目•Environmental behaviorof polymermaterials录•The DevelopmentTrends and Prospectsof Polymer Materialscontents01Overview ofPolymerMaterialsDefinition ofPolymer MaterialsSummaryDefinitionof polymersDetailed descriptionPolymers arelong chainmacromolecules formedby covalentbonding ofmany smallmolecules,usually withrepetitive structuralunits.They can be naturallypresent,such asproteins andnucleic acids,or theycanbesynthetic,such asplastics and synthetic fibers.Classification ofPolymer MaterialsSummaryDetailed descriptionClassificationof polymersPolymers canbe dividedinto naturalpolymersand syntheticpolymers basedon theirsource,structure,and properties.Natural polymerssuchas celluloseand protein,while syntheticpolymerssuch assynthetic rubberandsyntheticfibers.Inaddition,polymers canalso beclassified basedontheir thermal,electrical,and opticalproperties.Application ofPolymer Materials•Summary:Application ofPolymerMaterials•Detaileddescription:Polymer materialshave wideapplications invarious fields.In dailylife,polymermaterials are used to manufacture clothing,furniture,tableware,electronic products,etc.In industrialproduction,polymer materials areusedtomanufacturemechanical components,chemical equipment,building materials,etc.In addition,polymer materialshave importantapplications inmedical,aerospace,military andother fields.02The ChemicalBasis ofPolymerMaterialsTypes of polymerization reactionsAdditionpolymerizationA type of polymerization reaction in which monomersadd togrowing polymerchainswithout theloss ofsmall moleculesCondensationpolymerizationA type of polymerizationreaction inwhich twomonomer moleculescondenseto forma singlepolymer chainStepgrowth polymerizationAtypeof polymerizationreactioninwhichmonomer moleculesadd tothepolymer chainone ata time,using resultsin alinear structureNamingand structure of polymersPolymernames arecommonly derivedfrom thename of themonomer,with thesuffix-one or-one addedThestructure of polymers canvary dependingon the type ofpolymerizationreaction and the monomerusedSome commonpolymer structuresinclude linear,branched,crosslinked,and gradedpolymersSynthesis andModification ofPolymersPolymer modificationcan involvechanging the chemicalstructure,physical properties,or surfacecharacteristicsof a polymerPolymer synthesisinvolves theconversionof monomersintopolymers throughpolymerizationreactionsSome commonmethods ofpolymermodification includegrading,cross linking,andblending03The physicalpropertiesof polymermaterialsMolecularMovement andTransformation ofPolymersMolecularMovementPolymers havethe abilityto undergroundmolecular movementdue totheir longchainstructure Thismovement isessential forpolymer processingand canbe affectedbytemperature,pressure,and shearrateTransformationPolymer transformationoccurs whenthe chainschange theirconformation orconfigurationThis transformationcan leadto changes in thephysicalpropertiesofthepolymer,such asitselasticity,toughness,and glasstransition temperatureThemechanical propertiesof polymersElasticityTensile StrengthFlexibilityPolymers exhibitelastic behaviorPolymers canstand witha certainPolymers cango underflexibledue totheir abilityto recoveramount oftension stressbefore deformation,which allowsthemtheir shapeafter beingdeformed breakingThe tensestrength andto bendwithout breakingTheThe elasticmodulus measuresthe elongationat breakare importantflexible modularmeasures ofstiffnessof apolymer andmechanical propertiesthat stickinessof apolymer underdepends on thetypeof bonds determinethe usabilityof bendingloads andare criticalinand thechain configurationpolymers invarious applicationsdetermining thedurability ofpolymerproductsThermal propertiesof polymersMelting Point ThermalStability ThermalconductivityTheMeltingPointof apolymer isPolymers maydegrade athigh Polymershave lowthermalthe temperatureat whichthe temperaturesdue tochemical conductivitycompared tometalschains losetheir crystallinereactions betweenthe chainsThe andceramics Thisproperty makesstructureand beginto flowThe thermalstability ofapolymerpolymers suitablefor useinmelting pointis animportant dependson itschemical thermalinsulation applicationsparameterfor processingcomposition andthetypeof whereheat transferneeds tobepolymers anddependsonthe bondswithin thechains minimizedtypeofbondsandthechainconfiguration04Processing andFormingof PolymerMaterialsPreparationprocess beforeprocessingMaterial inspectionMixingEnsure thatthe rawmaterials Blendingthe rawmaterialsused areof goodquality andaccording tothe formulatocomply withthe requiredensure uniformityandstandards consistencyPelletizingDryingConvert themixed materialsRemove movementfrom theinto small pelletsfor easymixed materials to preventhandlingand processingmovement relatedissuesduring processingFormingprocessExtension01Force the molten polymerthrougha dieto formaLaminationspecific shapeor structureCombinemultiple layersofInjection moldingpolymerfilms usingheat and0402pressure tocreate compositeFeedthemoltenpolymer intostructuresamold underhigh pressuretocreate complexshapes withBlowingmoldingprecision dimensions03Form holdshapes byinflatingthe polymeragainst amoldProblems andSolutions inProcessingVariations inmaterial propertiesEnsureconsistent rawmaterial qualityand mixingproceduresto minimizevariationsProcessing differencesExperimentwith differentprocessing parametersto optimizetheprocessing conditionsWarpage and destructionControlthe coolingrate anduse appropriatemolds tominimizeWarpageanddestruction duringformattingSurface defectsIncreasesurface smoothnessby usingpolishing orcoatingtechniques afterprocessing05Environmentalbehavior of polymermaterialsThe aging phenomenon of polymersDescription of aging phenomenonPolymer materials undergochangesinphysical andchemical propertiesafter long-term useor exposuretospecific environmentalconditions,leading toa declinein theirperformance.Aging mechanismTheagingphenomenonis mainlyrelated tothe chemicalstructureofpolymer chains,environmentalfactors such as temperature,humidity,ultraviolet radiation,etc.,and microscopicdefects insidethepolymer.The impactofagingon performanceOvertime,the strength,toughness,and durabilityof polymersmay decrease,leading tomaterialsgradually becomingbrittle andbrittle.Environmental adaptabilityof polymersEnvironmentaladaptability Influencingfactors:The chemicalMethods toimprovedefinition:refers tothe abilityof structure,additives,environmental adaptability:Bypolymer materials to maintainmicrostructure,and surfacechangingthe chemical structuretheirperformance stabilityunder propertiesofpolymers can allofpolymers,adding stabilizers,orvarious environmentalconditions affecttheir environmentalperforming surfacetreatments,such astemperature,humidity,adaptability.the environmentaladaptability oflight,chemical corrosion,etc..polymerscanbe improved.Biodegradability ofpolymersBiodegradability isdefined asthe abilityofpolymer01materialstobe decomposedintosmallmoleculesand harmless substances bymicroorganisms in thenatural environment.The mechanismof biodegradation:Microorganisms02break downthechemicalbonds ofpolymers bysecretingenzymes,ultimately breakingthem downintoharmlesssubstancessuch aswater andcarbondioxide.Biodegradable applications:Degradable plasticscan03be used in fieldssuch asdisposable tableware,packaging materials,and agriculturalfilms to reducewhite pollution.06The DevelopmentTrendsandProspectsofPolymer MaterialsTheapplication ofnew materialsand technologiesNewpolymer materialsAdvanced processingtechnologyWith the development of science and technology,With thecontinuous development of processingmore and more new polymer materialsaretechnology,more and more advancedprocessingemerging,such ashigh performance polymers,methods ofpolymer materialshave beenpolymercomposites,polymer nanocomposites,developed,such asinjection molding,extrusionetc.,which havebroad application prospects inmolding,compression molding,etc.,which canthefields ofaerospace,automobiles,electronics,produce polymerproducts withcomplex shapesandother fieldsand highperformanceSustainable developmentofpolymer materials•Environmental protection:Polymer materialsare widelyusedindailylife,but alsobring abouta seriesof environmentalproblems Inorderto solvethese problems,it is necessary to pay attention to theenvironmentalprotection ofpolymer materialsin theproductionprocess,and tryto reducethe pollutionofpolymermaterialstotheenvironment•Resource saving:Polymermaterialsare nonrenewable resources,so itisnecessarytopayattentiontotheresource savingintheproduction processofpolymermaterials,and trytoreducethe consumptionof polymermaterialsFrontierresearch onpolymer materialsNewpreparation technologyNew applicationfieldWith thedevelopmentofscienceandWiththedevelopmentofscience andtechnology,moreandmorenewpreparation technology,polymermaterialsare appliedmoretechnologies ofpolymermaterialshave beenandmorewidely innew fields,such asdeveloped,suchaspolymerization method,biomedicine,energy storageand conversion,etc.,crystallization method,etc.,which canprepare whichprovides newapplicationprospectsforpolymer materialswith betterperformancepolymermaterials感谢您的观看THANKS。