资源描述：
《材料科学导论(英文课件)--青岛科技大学Polymer_structures_and_properties》由会员上传分享，免费在线阅读，更多相关内容在学术论文-天天文库。
1、TEMimageofthespherulitestructureinanaturalrubberspecimen.Chain-foldedlamellarcrystallitesapprox.10nmthickextendinradicaldirectionsfromthecenter.Thechain-foldedstructureforaplate-shapedpolymercrystallite.Chapter4PolymerStructures,Applications&ProcessingIntroduction•Natur
2、alpolymers:(1)Derivedfromplantsandanimals,suchaswood,rubber,cotton,wool,leatherandsilk.(2)proteins,enzymes,starches,andcelluloseinbiologicalandphysiologicalprocess.•Syntheticpolymers:plastics,rubbers,andfibermaterials.AfterWWII,thefieldofmaterialshasbeenvirtuallyrevolut
3、ionizedbytheadventofsyntheticpolymers.HydrocarbonmoleculesHydrocarbonmolecules:hydrogenandcarbon.Intramolecularbond:covalent.Saturatedandunsaturatedmolecules:saturated–allthebondsaresingleones(CH);4unsaturated–moleculeshavedoubleandtriplecovalentbonds(CH=CH,CH≡CH).22Pol
4、ymermolecules•Polymers-MacromoleculesC-Cbackboneformedbycovalentbonding.•Monomers•HomopolymersandcopolymersL=0.154nmMolecularconfigurationsMolecularcharacteristicsChemistrySizeShapestructure(mercomposition)(molecularweight)(chaintwisting,entanglement)linearbranchedcross
5、linkednetworkIsomericstatesstereoisomersGeometricalisomersisotacticatacticcistranssyndiotacticIsotactic全同立构Syndiotactic间同立构Atactic无规立构Poly(1,4-butadiene)Cis-顺式maleinoidTrans-反式trans-isomerismInLatin,transmeans"ontheotherside“;andcismeans"onthesameside"Trans-1,4-polyisop
6、rene:(反式聚1，4戊二烯)crystalline,hardrigidmaterialsHHCH2CH2CH2CH2CHCH33Cis-1,4-polyisoprene(Naturalrubber):(顺式聚1，4-戊二烯)amorphous,rubberymaterialCH3CH2CH2CH2CH2CH3CopolymersrandomalternatingblockgraftSyntheticrubbersLiquidcrystalpolymers(LCPs)LCPs:extended,rod-shapedandrigidm
7、olecules.Table13.12Callister5e
