尼龙成型制导

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1、MoldingGuidefMinlon®mineralreinforcednylonresinStartwithDuPontResinDescriptionMinlon®istheDuPonttrademarkforitsengineeringthermoplasticresins.ThepresentgradesofMinlon®aremineralandmineral/glassreinforcednylon66resins.Mineralparticlesandglassfibersarechemi-callyb

2、ondedwithnylonpolymertoprovideamaterialexhibitingtheexcellentchemicalresis-tanceandretentionofpropertiesathightempera-turescharacteristicofnylon,whileenhancingstiffness,strength,andheatresistance.Itisimportanttopointoutthatthesecompositionsarereinforced,notfille

3、d,resins,meaningthatthereisachemicalbondbetweenthenylonandthemineralormineralandglassparticles,thusgreatlyenhancingthetensileandstiffnessproperties.Minlon®alsoexhibitsbetterdimensionalstabilityandcreepresistancethanunreinforcednylonandlowerwarpagethanglassreinfo

4、rcednylon.MoldingConditionsCylinderTemperatureTheseproductscanbeprocessedreadilyinconven-tionalmoldingequipment.Typicalmoldingtem-peratureprofilesareshowninTable1.Usehigher-than-typicalrearzonetemperature(300°C[570°F]max.)to:•improvescrewrecoveryrates;•reducewea

5、rfromabrasionbetweenun-meltedparticlesandthescrewand/orbarrel;•reducetorqueloadsandstallingduringfastcycles.MeltTemperatureTypicalmelttemperaturesforeachresinareshowninTable1.Foroptimumtoughness,usemelttemperaturesinthemiddleofthetypicalrange.Highertemperaturesc

6、anbeusedtoimprovethesurfaceappearance.NozzleTemperaturesAreversetapernozzleisrecommended.TypicaltemperaturesarelistedinTable1.Highernozzletemperaturesmaybenecessaryduringstart-uptocompensateforcoldmoldsandpreventprematurefreeze-off.MoldTemperatureMoldtemperature

7、sinthe65-100°C(150-210°F)rangearenormallyused,althoughtemperaturesbetween100-115°C(210-240°F)aresometimesutilizedtoimprovefilling,surfacefinish,andtoreducethicksectionvoids.InjectionRatesSurfaceappearanceisaffectedbyinjectionspeed.Afast,one-secondinjectionspeedn

8、ormallygivesthehighestgloss.However,whenasemiglossappearanceisnotrequired,aslowerfillcanbeusedtoprovideanattractivemattefinish.InjectionPressureThemeltviscosityofthis