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1、1.Allmolecules,whetherthesmalltypeorthelargetypethatresultwhenparticularsmallmoleculesjointogether,aremadeupofatoms（suchascarbon,hydrogen,oxygen,ornitrogen）.Whenanysmallmoleculeisformed,theatomsjointogetherintoaspecificarrangementthatischaracteristicoftheparticularmole
2、cule.Thetypesofatomsandtheiraixangementdeterminethepropertiesofthemolecule.所有的分子，无论是小分子还是由特定小分子连在一起而产生的大分子，都是由原子组成（如碳，氢，氧，氮）。当任何一个小分子形成时，原子以特定排布连接在一起，这种排布为某一分子所特有。原子的类型及排布决定了分了的性质。2.Thebulkpropertiesaredeterminedbyboththemolecularproperties（propertiesthatdependuponthem
3、olecularnatureofthematerial,suchaschemicalreactivity）andthecollectiveproperties（propertiesthatdependupontheinteractionofthemolecules,suchascrystalformation）.Subsequentchaptersexamineboththemolecularandbulkpropertiesofplasticsbecauseunderstandingmanypropertiesofplastics
4、,suchasmechanicalstrength,meltingpoint,andsolventreactivity,dependsuponunderstandingboththemolecularandthebulknatureofplasticmaterials.（高分子的）整体性质由分子性质（由组成物质分子的特性所决定的性质，如化学反应活性）和聚集性质（由分子间相互作用所决定的性质，如晶型）所共同决定。随后的章节会分别考察分了性质和聚集性质，因为耍理解塑料的诸多特性，如机械强度，熔点和溶解性，须建立在理解塑料分了性质和整体特
5、性的基础Z上。1.Typicalmoldingprocessesareextrusion,injectionmolding,compressionmolding,andcasting.Moldingcompaniesthathaveplasticpartsastheirprincipalproductsusuallyhavemanyplasticprocessingmachinesandmakepartsinlargequantities・Typicalexamplesofthesecompaniesareplastic-pipee
6、xtniders,injectionmoldersofautomotiveparts,orplastic-toymanufacturers.典型的模制工序有挤岀成型，注入成型，挤压成型，铸造成型。拥有塑料零件并将其作为主要产品的成型公司一般有很多塑料成型加工设备，并大规模地制造零件。这些公司的典型例子有塑料管挤出商，机动零件的注射成型商，或者塑料玩具制造商。2.Thesolidstateofpolymericmaterialsis,insomeways,morecomplexthatthesolidstateofmostionic,
7、metallic,andsmallcovalentmolecules.Thecomplexityinpolymersarisesbecausesolidpolymericmaterialscanexist,intwoverydistincttypesofstructures.Inonetype,thepolymermoleculesarerandomlycoiledabouteachotherwithentanglement,calledamorphous.Inthesecondtypeofconfiguration,thepoly
8、mermoleculescanpacktogetherintoregular,repeatingstructuralpatterns.Theseregularlypackedregionsarecalledcrystalsorcrys
