塑料材料性能-1

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ABS丙烯腈-丁二烯-苯乙烯共聚物典型应用范围:汽车(仪表板,工具舱门,车轮盖,反光镜盒等),电冰箱,大强度工具(头发烘干机,搅拌器,食品加工机,割草机等),电话机壳体,打字机键盘,娱乐用车辆如高尔夫球手推车以及喷气式雪撬车等。注塑模工艺条件:干燥处理:ABS材料具有吸湿性,要求在加工之前进行干燥处理。建议干燥条件为80~90C下最少干燥2小时。材料温度应保证小于0.1%。熔化温度:210~280C;建议温度:245C。模具温度:25~70C。(模具温度将影响塑件光洁度,温度较低则导致光洁度较低)。注射压力:500~1000bar。注射速度:中高速度。化学和物理特性:ABS是由丙烯腈、丁二烯和苯乙烯三种化学单体合成。每种单体都具有不同特性:丙烯腈有高强度、热稳定性及化学稳定性;丁二烯具有坚韧性、抗冲击特性;苯乙烯具有易加工、高光洁度及高强度。从形态上看,ABS是非结晶性材料。中单体的聚合产生了具有两相的三元共聚物,一个是苯乙烯-丙烯腈的连续相,另一个是聚丁二烯橡胶分散相。ABS的特性主要取决于三种单体的比率以及两相中的分子结构。这就可以在产品设计上具有很大的灵活性,并且由此产生了市场上上百种不同品质的ABS材料。这些不同品质的材料提供了不同的特性,例如从中等到高等的抗冲击性,从低到高的光洁度和高温扭曲特性等。ABS材料具有超强的易加工性,外观特性,低蠕变性和优异的尺寸稳定性以及很高的抗冲击强度。GenericClassABS(Acrylonitrile-Butadiene-Styrene)TypicalApplicationsAutomotive(instrumentandinteriortrimpanels,glovecompartmentdoors,wheelcovers,mirrorhousings,etc.),refrigerators,smallappliancehousingsandpowertoolsapplications(hairdryers,blenders,foodprocessors,lawnmowers,etc.),telephonehousings,typewriterhousings,typewriterkeys,andrecreationalvehiclessuchasgolfcartsandjetskis.InjectionMoldingProcessingConditionsDryingABSresinsarehygroscopicanddryingisrequiredpriortoprocessing.Suggesteddryingconditionsare80-90C(176-195F)foraminimumof2hours.Resinmoisturecontentshouldbelessthan0.1%MeltTemperature200-280C(392-536F);Aim:230C(446F)MoldTemperature25-80C(77-176F).(Moldtemperaturescontroltheglossproperties;lowermoldtemperaturesproducelowerglosslevels)ResinInjectionPressure500-1,000bar(7,250-14,500psi)InjectionSpeedModerate-highChemicalandPhysicalPropertiesABSisproducedbyacombinationofthreemonomers:acrylonitrile,butadiene,andstyrene.Eachofthemonomersimpartdifferentproperties:hardness,chemicalandheatresistancefromacrylonitrile;processibility,gloss,andstrengthfromstyrene;andtoughnessandimpactresistancefrombutadiene.Morphologically,ABSisanamorphousresin.Thepolymerizationofthethreemonomersproducesaterpolymerwhichhastwophases:acontinuousphaseofstyrene-acrylonitrile(SAN)andadispersedphaseofpolybutadienerubber.ThepropertiesofABSareaffectedbytheratiosofthemonomersandmolecularstructureofthetwophases.Thisallowsagooddealofflexibilityinproductdesignandconsequently,therearehundredsofgradesavailableinthemarket.Commerciallyavailablegradesofferdifferentcharacteristicssuchasmediumtohighimpact,lowtohighsurfacegloss,andhighheatdistortion.ABSofferssuperiorprocessibility,appearance,lowcreepandexcellentdimensionalstability,andhighimpactstrength.MajorManufacturersDowChemical(Magnumgrades),GEPlastics(Cycolac),Bayer(Lustran),BASF(Terluran),ChiMei(Polylac),LGChemical(Lupos),CheilSynthesis.PC/ABS聚碳酸酯和丙烯腈-丁二烯-苯乙烯共聚物和混合物典型应用范围:计算机和商业机器的壳体、电器设备、草坪和园艺机器、汽车零件(仪表板、内部装修以及车轮盖)。注塑模工艺条件:干燥处理:干燥处理是必须的。湿度应小于0.04%,建议干燥条件为90~110C,2~4小时。熔化温度:230~300C。模具温度:50~100C。注射压力:取决于塑件。注射速度:尽可能地高。化学和物理特性:PC/ABS具有PC和ABS两者的综合特性。例如ABS的易加工特性和PC的优良机械特性和热稳定性。二者的比率将影响PC/ABS材料的热稳定性。PC/ABS这种混合材料还显示了优异的流动特性。PC聚碳酸酯典型应用范围:电气和商业设备(计算机组件、连接器等),器具(食品加工机、电冰箱抽屉等),交通运输行业(车辆的前后灯、仪表板等)。注塑模工艺条件:干燥处理:PC材料具有吸湿性,加工前的干燥很重要。建议干燥条件为100C到200C,3~4小时。加工前的湿度必须小于0.02%。熔化温度:260~340C。模具温度:70~120C。注射压力:尽可能地使用高注射压力。注射速度:对于较小的浇口使用低速注射,对其它类型的浇口使用高速注射。化学和物理特性:PC是一种非晶体工程材料,具有特别好的抗冲击强度、热稳定性、光泽度、抑制细菌特性、阻燃特性以及抗污染性。PC的缺口伊估德冲击强度(otchedIzodimpactstregth)非常高,并且收缩率很低,一般为0.1%~0.2%。PC有很好的机械特性,但流动特性较差,因此这种材料的注塑过程较困难。在选用何种品质的PC材料时,要以产品的最终期望为基准。如果塑件要求有较高的抗冲击性,那幺就使用低流动率的PC材料;反之,可以使用高流动率的PC材料,这样可以优化注塑过程。PC(Polycarbonate)TypicalApplicationsElectronicandbusinessequipment(computerparts,connectors,etc.),appliances(foodprocessors,refrigeratordrawers,etc.),transportation(headlights,taillights,instrumentpanels,etc.).InjectionMoldingProcessingConditionsDryingPCresinsarehygroscopicandpre-dryingisimportant.Recommendeddryingconditionsare100-120C(212-248F)for3to4hours.Moisturecontentmustbelessthan0.02%priortoprocessing.MeltTemperature260-340C(500-644F);higherrangeforlowMFRresinsandvice-versaMoldTemperature70-120C(158-248F);higherrangeforlowMFRresinsandvice-versaFillPressureAshighaspossibleforrapidmoldingInjectionSpeedSlowinjectionspeedswhensmalloredgegatesareused;highspeedsforothertypesofgatesChemicalandPhysicalPropertiesPolycarbonateisapolyesterofcarbonicacid.Allgeneral-purposepolycarbonatesarebasedonbisphenolA.ThebisphenolAcomponentofthemoleculecontributestothehighglasstransitiontemperature(150C/302F).Therotationalmobilityofthecarbonylgroupwithinthemoleculecontributestothehighductilityandtoughnessoftheresin.PCisanamorphousengineeringresinwithexceptionallygoodimpactstrength,heatresistance,clarity,sterilizability,flameretardancy,andstainresistance.ThenotchedIzodimpactstrengthofPCisveryhighandmoldshrinkageislowandconsistent(.1-.2mm/mm).HighmolecularweightPCs(whichtranslatetolowmeltflowrate)havehighermechanicalproperties,butprocessibilityofsuchresinsbecomesdifficult.ThetypeofPCchosenforaparticularapplicationshouldbebasedonthedesiredcriteria(forhighimpactproperties,usealow-MFRPC;conversely,foroptimalprocessibility,useahigh-MFRPC).ThemeltviscositiesaretypicallyNewtonianuptoshearratesof10001/sanddecreasebeyondthat.TheHeatDeflectionTemperatureUnderLoadistypicallybetween130-140C(266-284F)andtheVicatSofteningPointistypicallyaround155C(311F).MajorM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