Lesson 11　Ionic Polymerization

    StrongLewisacids,thatis,electronacceptors,areoftencapableofinitiatingadditionpolymerizationofmonomerswithelectron-richsubstituentsadjacenttothedoublebond①.CationiccatalystsaremostcommonlymetaltrihalidessuchasAlCl3orBF3.Thesecompounds,althoughelectricallyn......查看详细>>

标签:聚合物科学与工程

Lesson 12　Rubber Elasticity

    Naturalandsyntheticrubberspossesssomeinteresting,unique,andusefulmechanicalproperties.Noothermaterialsarecapableofreversibleextensionof600%～700%.Noothermaterialsexhibitanincreaseinmoduluswithincreasingtemperature.Itwasrecognizedlongagothatvulcanizationwas......查看详细>>

标签:聚合物科学与工程

Lesson 13　Flow Curves of Polymer Fluid

    Whenmostmaterialsaresubjectedtoaconstantshearrate(orconstantshearstress)atafixedtemperature,acorrespondingsteady-statevalueofshearstress(orshearrate)issoonestablished①.Thesteady-staterelationbetweenshearstressandshearrateatconstanttemperatureisknownasaflo......查看详细>>

标签:聚合物科学与工程

Lesson 14　Polymer Melts and Solutions

    Whentheflowpropertiesofpolymermeltsandsolutionscanbemeasuredoverawideenoughrangeofshearing,thelogarithmicflowcurvesappearasinFigure14.1.Itisgenerallyobservedthat:(1)Atlowshearrates(orstresses),a‘lowerNewtonian’regionisreachedwithaso-calledzero-shearviscos......查看详细>>

标签:聚合物科学与工程

Lesson 15　Linear Viscoelasticity of Polymer

    Engineershavetraditionallydealtwithtwoseparateanddistinctclassesofmaterials:theviscousfluidandtheelasticsolid.Designproceduresbasedontheseconceptshaveworkedprettywellbecausemosttraditionalmaterials(water,air,steel,concrete),atleasttoagoodapproximation,fit......查看详细>>

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Lesson 16　Plastics

    Plasticsaresyntheticorman-madematerialswhichhaveuniqueandremarkableproperties.Manydifferentplasticsmaybeobtainedbymanipulatingthemoleculesandchangingthechemicalcombinations.Plasticshaveimportantrolesinagriculture,appliances,clothing,construction,electroni......查看详细>>

标签:聚合物科学与工程

Lesson 17　Thermoplastic Materials and Polyethylene

    ThermoplasticMaterialsItisimportanttobecomefamiliarwiththeoutstandingphysicalandchemicalpropertiesofthermoplasticplasticssoyoucanmakewiseselectionsfortheiruse.Youshouldunderstandhowandwhythesematerialscanbeprocessedincertainways.Therelationshipbetweenthep......查看详细>>

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Lesson 18　Vinyl Resins and Polyvinyl Chloride

    Vinylresinscoverabroadgroupofmaterialsthatrangeinpropertiesfromhardrigidproductstosoftflexibleformulations.Theyarederivedfromthe“vinyl”radical:CH2CH2.Variousatomsorsidegroupsmaybeattachedtothevinylradicaltoproducepolymersofvaryingproperties.Thelargestpoly......查看详细>>

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Lesson 19　Styrene-Acrylonitrile(SAN)and Arylonitrile-Butadiene-Styrene(ABS)

    Acopolymerofstyrene,styreneacrylonitrilehasimprovedpropertiesofstiffness,chemicalandscratchresistanceandhigherheatresistance.ItisproducedbythecopolymerizationofacrylonitrileandstyrenetoformtheSANpolymer.Duetothecopolymerization,thewater-whitecolorofpolyst......查看详细>>

标签:聚合物科学与工程

Lesson 20　Polycarbonate

    Therearefewthermoplasticsthathavetheoutstandingengineeringpropertiesofpolycarbonate.Inrecentyearsithastakenitsplaceamongthemostvaluableresinsoftheindustry.Polycarbonateisamemberofthepolyesterfamilyinthatitcontainscarbonandoxygenatomsasthebackboneofthemole......查看详细>>

标签:聚合物科学与工程