Developmentprocess
Plasticsarewidelyusedandareindispensablecomponentsinhomeappliances,automobiles,mobilephones,PCs,medicalequipment,andlightingappliances.Asmycountry'seconomyhasachievedsustainedandstablegrowth,homeappliances,automobiles,mobilephones,PCs,medicalequipmentandotherindustrieshavebenefitedfromagoodexternalenvironmentandhaveachievedrapiddevelopment.Thedevelopmentofdownstreamindustrieshasfurtherstimulatedthedemandforplastics.In2010,therewere2286companiesinChina'splasticpartsmanufacturingindustry,ayear-on-yearincreaseof24.54%;salesrevenuereached106.125billionyuan,ayear-on-yearincreaseof26.38%.
DuringtheTwelfthFive-YearPlanperiod,mycountry'sdownstreamindustriessuchasautomobiles,homeappliances,consumerelectronics,andmedicaldeviceswillcontinuetomaintainrapiddevelopment.Thedemandforplasticpartsintheseindustrieswillcontinuetoexpand,andthedemandwillalsobehigh-end,Precisiontrend.Itisestimatedthatduringthe12thFive-YearPlanperiod,thesalesscaleofChina'splasticpartsmanufacturingindustrywillreach170billionyuan.AccordingtoasurveybyCIC,China’splasticpartsmanufacturingindustry’stechnologicalinnovationcapabilitieshavebeenfurtherenhanced,andthenumberofcorporatetechnologyR&Dcentershascontinuedtoincrease;theindustrialstructure,corporatestructure,andproductstructurehavebeencontinuouslyadjusted,andtheindustrialintensificationhasbeengraduallyupgraded;theoveralladvantagesoftheindustryhavebeenfurtherimprovedandStrengthening,thegapwiththedevelopedcountriesintheworldisgraduallynarrowing,andsomeaspectshavereachedtheworld'sadvancedlevel,enteringacriticalperiodofsustainabledevelopmentfromalargecountrytoanadvancedpower.TheplasticpartsmanufacturingindustryinJiangsu,Zhejiang,Shanghai,Guangdongandotherplacesisbooming.Boththenumberofenterprisesandthescaleofproductionandsalesareinaleadingpositioninthecountry,andtheregionalconcentrationoftheindustryisrelativelyhigh.Atthesametime,domesticenterpriseshavealsoachievedrapiddevelopment,andthestrengthofindustry-leadingenterpriseshasfurtherstrengthened.Butatthesametime,advancedforeigncompaniesarealsooptimisticaboutthedomesticmarketandgraduallyincreasetheirinvestment.TheentryofmultinationalcompaniessuchasNapro,Hi-PInternationalGroup,AnNengliGroupandothermultinationalcompanieshasmadecompetitionintheindustrymoreintense.
Accuracytesting
Withtherapiddevelopmentoftheplasticindustryandthecontinuousimprovementofplasticperformance,plasticpartshavebeenmorewidelyused,andplasticpartsarereplacingtraditionalmetalsindifferentfields.Parts,areasonablydesignedplasticpartcanoftenreplacemultipletraditionalmetalparts,soastoachievethepurposeofsimplifyingtheproductstructureandsavingmanufacturingcosts.Therefore,inaccordancewiththerequirementsofplasticsapplicationsinthefieldofplasticsaccuracyandcombinedwithmarketanalysis,recommendedinstrumentssuitableforplastictestingincludeMUMAportableimagers,VMSseriesopticalimagemeasuringinstruments,VMLseries3Dopticalimagemeasuringinstruments,andsoon.
ChineseandEnglishpronunciation
Plasticpinyin:sujiao
PlasticcementinEnglish:plasticcement
Definition
Thedefinitionofplastic:mainlycomposedofcarbon,oxygen,hydrogen,nitrogenandotherorganicorinorganicelements.Thefinishedproductisasolid.Itisamoltenliquidduringthemanufacturingprocess,soitcanbeheatedbymachinetomeltandpressurizedtomakeitItflowsandcoolstosolidifyandformvariousshapes.Thislargeandvariedgroupofmaterialsiscalledplastic.
Plastic(English:Plastic):referstothehighmolecularweightsyntheticresinasthemaincomponent,addingappropriateadditives,suchasplasticizers,stabilizers,flameretardants,lubricants,colorants,etc.,Processedplastic(flexible)materials,orrigidmaterialsformedbycuringandcrosslinking.
Application
Plasticpartsarewidelyusedineveryfieldoflifetoday,suchashouseholdappliances,instrumentation,wiresandcables,constructionequipment,communicationelectronics,automotiveindustry,aerospace,JapanUsehardware,etc.Theapplicationofplasticissowideandtheuseissoconvenientthatithasbroughtsideeffects.Insomeareas,peoplehavetoimplement"plasticbans."
Rawmaterials
1.Themaincomponentofplasticrawmaterialsiscarbon-containingcompounds.
2.Plasticrawmaterial:Itismadeofhighmolecularsyntheticresin(polymer)asthemaincomponent,andisinfiltratedwithvariousauxiliarymaterialsoradditives.Underaspecifictemperatureandpressure,ithasplasticityandfluidityandcanbemolded.Amaterialthatismoldedintoacertainshapeandremainsunchangedundercertainconditions.
3.Polymer:referstothepurematerialorpolymerizedmaterialproducedduringthepolymerizationprocess.Bothnaturalandsyntheticresinsarehighmolecularpolymers,referredtoaspolymers.
4.Plastichasgoodinsulationagainstelectricity,heatandsound:electricalinsulation,arcresistance,heatpreservation,soundinsulation,soundabsorption,vibrationabsorption,andexcellentnoisereductionperformance.
Mostoftheplasticrawmaterialsareextractedfromsomeoils.ThemostfamiliarpartofPCmaterialsisextractedfrompetroleum.PCmaterialshaveagasolinesmellwhentheyareburned;ABSisderivedfromcoalABSissoot-likewhenitisburnedout.POMisrefinedfromnaturalgas,andPOMwillhaveaverysmellygaswhenitisburnedout.
Identificationmethod
Theidentificationmethodofplasticusuallyadoptsappearanceanduse,densitytest,softeningpointormeltingpoint,combustiontest,comprehensiveidentificationmethodtoidentify,thefollowingintroducesseveralcommonlyusedmethodsForeveryonetolearn:
Appearanceanduse
Toanalyzeanunknownpolymersample,firstlookatitbyhandandmakeapreliminaryjudgmentonitsappearance.Whichcategorydoesitbelongto.Ifpossible,understanditssourceanduseasmuchaspossible;
◎Transparencyandcolor
Crystalline→Translucent/opaque(PP,PE,Nylon,POM,PET,…)
Amorphous→Transparent(PC,PMMA,GPPS,SAN,PPO)
◎Handfeelingandmechanicalproperties
Theapproximatestrengthandtoughnessofthematerialcanbesensedbyhand,squeezed,beatenorbent.Thehardnessofthematerialcanbejudgedbyscratchingwithanail(orwiththeaidoftoolssuchasnails).ThesecanbeusedtoinitiallyidentifythematerialTheroughtype.
◎Useofplasticproducts
Itisverydifficulttoqualitativelyidentifywithoutbackgroundknowledge.However,ifthesourceofthesampleandotherbackgroundknowledgeoftheusesituationareknown,theidentificationThescopeisgreatlyreduced.
Forexample:non-brokenplasticvacuumflaskwithinnerliner
Densitytest
Iso-densitymethod(refertoASTMD1505;ISOR1183MethodD)
Thedensityofthesolidcanbemeasuredbysuspendingthesolidtobemeasuredinaliquidofknowndensity(thatis,thedensityisequal).
Thespecificgravityofthesolution
Industrialalcohol0.8sodiumchloride1.22
water1zincchloride1.63
magnesiumchloride1.33
combustiontest
◎Themethodofthecombustiontestisverysimple.Usetweezersoraspatulatosupportasmallsampleandheatitdirectlywithaflame.Generally,letthecornerofthesamplebeclosetotheedgeoftheflame.Forsamplesthatareeasytoignite,youcandistinguishfirstComeout,andthenputitontheflame,andsometimesremoveittodeterminewhetherthefirewillcontinuetoburn.
◎Theflammabilityofthematerialisrelatedtotheelementsitcontains.
CombustibleElements-carbon,chlorine,sulfurandothernon-flammableelements-halogen,phosphorus,nitrogen,silicon,boron,etc.
Thecoloroftheflameisusuallyrelatedtotheelement
Yellow-onlycarbon,Hydrogenplastics,suchasPS
Blue-oxygen-containingplastics,suchasPOM
Green-chlorine-containingplastics,suchasPVC
White-burningintensePlastics,suchasnitrocellulose.
Characteristicsofrawmaterials
a.Plasticrawmaterialsexpandbyheat,andthecoefficientoflinearexpansionismuchlargerthanthatofmetals;
b.Thestiffnessofgeneralplasticrawmaterialsisoneorderofmagnitudelowerthanthatofmetals;
c.Themechanicalpropertiesofplasticmaterialswillbesignificantlyreducedunderlong-termheating;
d.Generalplasticmaterialsaresubjecttolong-termstressundernormaltemperatureandbelowtheiryieldstrengthForce,therewillbepermanentdeformation;
e.Plasticmaterialsareverysensitivetonotchdamage;
f.Themechanicalpropertiesofplasticmaterialsareusuallymuchlowerthanthatofmetals,butsomecompositematerialsThespecificstrengthandspecificmodulusarehigherthanthatofmetal.Iftheproductdesignisreasonable,itwillbemoreadvantageous;
g.Generally,themechanicalpropertiesofplasticrawmaterialsareanisotropic;
h.Someplasticmaterialswillabsorbmoistureandcausesizeandperformancechanges;
i.Someplasticsareflammable;
j.Thefatiguedataofplasticmaterialswasstillavailablebefore2005Veryfew,itneedstobeconsideredaccordingtotherequirementsofuse.
Classificationofrawmaterials
Accordingtothemolecularstructureofsyntheticresins,plasticrawmaterialsaremainlydividedintothermoplasticandthermosettingplastics:forthermoplastics,itisrepeatedPlasticsthatarestillmalleablewhenheated:mainlyincludePE/PP/PVC/PS/ABS/PMMA/POM/PC/PAandothercommonlyusedrawmaterials.Thermosettingplasticsmainlyrefertoplasticsmadeofsyntheticresinsthatarehardenedbyheating,suchassomephenolicplasticsandAminoplastic,notcommonlyused.
Accordingtothescopeofapplication,therearemainlygeneralplasticssuchasPE/PP/PVC/PS,etc.,engineeringplasticssuchasABS/POM/PC/PAandothercommonlyusedones.Inaddition,thereareSomespecialplastics,suchashightemperature,highhumidityandcorrosionresistance,andotherplasticsmodifiedforspecialpurposes.
Processing
1.Mostoftheplasticrawmaterialscanberecycled,However,sincetheplastic(nozzlematerial)usedforturningismorebrittlethanthegeneralrawmaterials,itcanonlybeusedwithnewmaterials(rawmaterials),andthemaximumproportionshouldnotexceed25%.Itshouldbebasedontheprincipleofcustomerrequirements.VarioustypesofplasticmaterialsBecausetherequiredmeltingpointisdifferentandtheinjectionpressureisdifferent,itmustnotbeconfusedinproduction.
2.Becauseplasticproductsneedtobematchedwithcolor,plasticrawmaterialscanbedividedinto:pumpedpellets,colorPowderandcolormaterials,suchasaddingliquidtocolortheplasticrawmaterialstoday.Therawmaterialforpumpingparticlesisthatthepigmenthasbeenmixedintotherawmaterial,andeachplasticmaterialhasbeencolored,sothecoloroftheproductisstableanduniform.Thematerialistheuseofmixedrawmaterialsofcolorspeciesortoner,whichislowcostanddoesnotneedtostorealargeamountofcoloredrawmaterials.However,thecolorisunstableanditisdifficulttocontroluniformityinproduction.
Coloring
Thecolormatchingofplasticsisthekeytothecoloringofplastics.Onlywithagoodcolorcanweprepareproductswithgoodluster.Inthecolormatchingprocess,wemustfirstclarifytheapplicationrequirementsoftheproduct,andselecttheappropriatecolorantaccordingtothecoloringperformanceoftheplasticmaterial.Whenselectingcolors,techniciansshouldstrictlycheckthecolor,tintingstrength,dispersibility,performance,balancedstabilityofprocessing,mixingandcostoftheavailablepigments,andthencanselectthepigmentstobeusedanddeterminetheamountusedinitially.Thequalityofcolorselectionandcolormatchingnotonlydependsonthetechnicalexpertiseofthetechnicians,butalsorequiresthetechnicianstohavesoundvisualfunctions.Atthesametime,itmustrelyonhigh-techcolormatchinginstrumentsandequipment.Thisarticlediscussesplasticcolormatchingproceduresandcolormatchingmethods.
Colormatchingprogram
Colormatchingisanimportantpartofcoloring.Thefirstchoiceforcolormatchingistodesignthepreliminaryformula,andthenadjustthepreliminaryformulatomakeitsuitableformassproduction,andEnsuretheuniformityofthecolorofplasticproducts.
1.1Preliminaryformulationdesign
(1)Accordingtotherequirementsoftheoveralldesignofplasticproducts,findasamplesimilartothestandardcolorsampleasareference.Whetherthereferenceobjectisselectedproperlyornotisdirectlyrelatedtothequalityofthecoloringeffect.Inordertofindabettercoloringreferencematerial,weshouldaccumulateandpreparemorecoloringplasticswatchesorplasticcolormaterialsforreference.Atthesametime,weshouldcompileourowncolorselectionexperienceandlessonsintocorrespondingcoloringformulas.referto.
(2)Intheabsenceofareference,carefullyobserveandanalyzethecolorshade,hueandbrightnessoftheplasticproduct(sample),determinethecolorattribute,anddeterminewhetherthecolorusedistransparentoropaque,Whetheritcontainsotherspecialpigments(suchasfluorescentpigments,metallicpigments,etc.),andthencoloraccordingtoMunsellcolorsystem.
(3)Repeatedlycomparethedifferencebetweenthestandardcolorsampleandthereferenceobjectfromtheaspectsofhue,brightness,intensity,etc.,onthisbasis,correctthecolorantformulaofthereferenceobject,anddrawupapreliminaryformula.
OrdesigntherequiredcoloraccordingtothecalibrationprincipleofMunsellcolorsystem,anddrawupapreliminaryformula.
1.2AdjusttheformulaAccordingtotheproposedpreliminaryformula,carryouttheactualcoloringtest,comparetheobtainedactualcolorsamplewiththestandardcolorsampleandthereference,andfurtheradjustthecoloringformula.Thenpreparerealsamplesaccordingtotheadjustedformulaforcomparison.
Adjusttheformulaagainandrepeatthismanytimesuntiltheactualcolorofthesampleisthesameasthestandardcolorsampleoristheclosesttothestandardcolorsample.Tothedegree.Finally,thecoloringformulaisdeterminedforproduction.However,theselectedcolorisusuallydifferentfromthecolorpresentedbytheplasticproductsinactualproduction.Thecauseofthesedifferencesislargelyduetocolorweighingerrors.Sohowtomakethecolormatchingaccurate?Howtomakethecolormatchingconsistentincontinuousproduction?
Theaccuracyofcolormatchingisbasedontheselectionofthecorrectcolor(dye)material,andthecolor(dye)materialselectionisbasedontheproductTounderstandtheeffectandobservethesample,theunderstandingandobservationofthesampledependsontheexperienceandskillsofthecolormatchingpersonnel.Nowadays,manyunitsuseinstrumentstomatchcolors,butsomeunitsstillusemanualvisualinspectiontomatchcolors.Althoughthecolormatchingmethodofmanualvisualinspectionissimple,itrequiresthevisualinspectionpersonneltohaverichexperience.Whentwoobjectsareviewedunderthesamelightsource(suchassunlight),theircolorsmaybedifferent.Similarly,foroneobserver,thecolorsoftwoobjectsmaybeexactlythesame;foranotherobserver,theymaybedifferent.Wecallthesetwoobjectsconditionalisochromaticbodyorconditionalisochromaticpair,andalsocalledconditionalcolormatchingbodyorvariablecolormatchingbody.Iftwoobjectsarerequiredtolookthesameunderanylightsource,itmeansthatthespectroscopicreflectioncurvesofthetwoobjectsmustbethesame.Thiskindofcolormatchingiscalledunconditionalcolormatchingorimmutablecolormatching.Immutablecolormatchingrequirestheuseofthesamecolorantinthecolorsample.Itisimpossibletoadjustthecolorofplastictotheextentofimmutablecolormatching.Therearemanyreasonsforthis.Forexample,thedegreeofdispersionofthesamepigmentisdifferentindifferentplastics;inaplastic,itissometimesnecessarytodecolorortoningtoremoveothercolorsintheoriginalplastic;Inanothertypeofplastic,thisadjustmentmaynotbenecessary.Afterunderstandingtheseconditions,weknewwhattodointheactualcolormatchingprocessanddidnotpursueimmutablecolormatching.Sincethecolorswematchareallvariablecolormatching,whichconditionshouldweuseasthecriterion?Thisrequiresspecificanalysisofspecificissues.Theprincipleistosimulatethefinaluseenvironmentoftheproductasmuchaspossibletoobserveandmatchthecolor.Iftheproductisultimatelyusedoutdoors,thecolorselectionshouldalsobeperformedundernaturallightwhenmatchingcolors.
Colormatchingmethod
2.1Visualcolormatching
Anexperiencedcolormatchingpersonmusthaveaclearerconceptofthecolorantheneedsbeforecolormatching.Itisnecessarytograspthegeneralrulesofcoloringbymixingcolorants,andalsohaveaclearunderstandingofthepropertiesofthecolorantsused,suchashue,shade,mobility,heatresistance,weatherresistance,chemicalstability,etc.,andaccumulaterepresentativeVariousplasticcoloringsamplesandcolormatching.Beforefindingasuitablecolorantformula,alotofexperimentsmustbecarriedout,andthesamecolormustberepeatedlytoneduntiltherequiredcolorisobtained.Obviously,thevisualcolormatchingmethodisatrialanderrormethod,notveryscientific.Becausethismethodisrelativelysimpleandpractical,itisstillwidelyused.However,thismethodistime-consumingandrequiresoperatorstohaverelativelyrichexperience,otherwiseitwillbedifficulttooperate.
2.2Instrumentcolormatching
Theinstrumentcolormatchingmethodisderivedfromthevisualcolormatchingmethod.Thismethodusesaspectrophotometerandothermeasuringinstrumentstoreplacethefunctionsofthehumaneyeandbrain.Thetrial-and-errorprocessofthecolorratioiscarriedoutbycomputersimulation,withouttheactualmixingofthecoloringoftheplastic.Theoperatoronlyneedstomeasurethereflectance,whichisitsstandardvalue,andselectthepigmentforcolormatching.Byadjustingtheconcentrationofcolormatchingpigments,themeasurementsystemisconsistentwiththestandardconversionvalue.Ifthepigmentselectedbytheoperatorisreasonable,thesystemwilloutputaformulaintheformofmassfraction,andthenconvertthepercentageformulaintoamassratio.
Ifyou(qualitatively)knowwhatkindofcoloringagentthesampleuses,thecomputercaneasilycalculatetheactualamountofvariouscolor(dye)materialsintheformula.However,theformulaofthecolorantusedinthesampleisoftenunknown.Inthiscase,thechromaticitycoordinatesofthesamplecanbeusedtomatchthecolor.Therearemanyanalyticalandempiricalrelationshipsusedtoselecttheappropriatecolorantformulationanddeterminetheconcentrationappliedtoeachformulation.Theestablishmentoftheserelationshipsrequiresalotofcalculations.Usingacomputercanshortenthetimeoftheentirecolormatchingprocesstotenminutes.
Onecolorcanbeformulatedfromseveralformulascontainingdifferentpigments.Theperformancecharacteristicsandingredientsoftheseformulationsaredifferentfromeachother.Youcanusecolormatchinginstrumentsandcomputerstogetavarietyofformulasforacolor,forcolormatchingoperatorstochoose,toseewhetheritiseconomicaltouseasmallamountofexpensiveorganicpigmentsoralargeamountofcheapinorganicpigments,sothatpeoplehavealargerSelecttherange.
Inaddition,theinstrumentcolormatchingandvisualcolormatchingoffluorescentmaterialsareverydifficult.Thisisbecausefluorescenceisanewvariable.Whentwosamplesarecomparedunderdifferentlightsources,differentresultsmayappear.Notonlythelightsourcewillaffecttheobservationofthespecimen,buttheanglebetweentheincidentlightandtheobservationpositionwillalsoaffecttheobservationofthespecimen.
Mattersneedingattention
Whentoning,youmustfirstpayattentiontotheshadeofthecolorant.Inadditiontoitsnaturalcolor,eachcolorantalsohasitsownshade,whichisrelatedtoacertainstandard.Incontrast,thesecondarypigmentsthatexistincolorarecalledshades.Suchasphthalocyaninegreenwithyellowlight,mediumchromeyellowwithredlightandsoon.Ifthemediumchromeyellowismatchedwithphthalocyaninegreen,itmustbeavoidedduetotheinterventionoftheredlightofthemediumchromeyellow,therearethreeprimarycolorsofred,yellowandblue,whichwillmakethematchedcolordark.Therefore,inordertoobtainbrightcolors,whenthetwocolorantsarecombined,payattentiontotheinterferenceofthecolorlight.Intheactualpreparationofpurered,Litholscarletandlightfastscarletcanbeusedtomixtogether,sothattheiryellow,blue(purple)andothershadesareoffset,andwhitecolorantsareaddedtoimproveitsbrightness.
Classification
Accordingtothermalperformanceandprocessingperformance
Thermoplastics:softenedbyheatandcanberepeatedlyheatedformolding
Suchaspolyvinylchlorideplastics,polypropyleneplastics
Thermosettingplastics:cannotbeheatedandmeltedafterbeingcuredandshapedbyheating
Suchasphenolicplastics,urea-formaldehydeplastics
Byuse
General-purposeplastics:largeoutput
Suchaspolyethylene,polypropylene,polyvinylchloride
engineeringplastics
p>Suchaspolycarbonate,polysulfone,polyphenyleneether,polyamide,polyoxymethylene
Specialplastics
Suchasmedicalplastics,conductiveplastics,high-temperatureplastics
p>Environmentalissues
Sinceitsintroduction,plasticshavebeenwidelyused,buttheyhavealsocausedseriousenvironmentalproblems.Plasticwasteisdifficulttodecomposenaturally,leadingtoanincreaseinsolidwaste;ifitflowsintotheocean,itwillalsocausemarinelifetoeat,suffocate,poisoning,etc.,whichwillaffectthemarineecology;incinerationofplasticwastewillalsocauseairpollution,andsomeplastics,suchaspolychlorideUndercertainconditions,ethylene(PVC)andpolycarbonate(Polycarbonates)mayreleaseharmfulsubstancesorendocrinedisruptors,whichendangerthefertilityoforganisms.Therefore,reducingtheuseofplastichasbecomeanimportanttaskinenvironmentalprotection.
Recyclingclassification
Inordertofacilitatetherecyclingofplastics,TheSocietyofthePlasticsIndustry,Inc.,USAproposedalabelingsystemthatusesplastictypestoclassify:""Syntheticresinidentificationcode"(ResinIdentificationCode,oftentranslatedas"plasticmaterialcode"or"plasticcode").Recyclableplasticcontainerswillhaveatriangularlabelsurroundedbythreearrows,andthelabelwillindicatethetypeofplastic.
TheChineseNationalStandard(GB18455-2001)stipulatesthatplasticpackagingproductsorplasticcontainerswithavolume/volumeexceeding100mlmustbevisuallymarkedwiththeplasticrecyclinglabel:
Signabbreviatednameandpurpose
p>PETpolyethyleneterephthalate,alsooftencalledpolyester,iscommonlyfoundinPETbottles.
HDPEhigh-densitypolyethyleneiscommonlyfoundinlotioncontainers,milkbottles,andsupermarketplasticbags.
PVCpolyvinylchlorideiscommonlyfoundinpipes,outdoorfurniture,andraincoats.
LDPElow-densitypolyethyleneiscommonlyusedinthetubepackagingoftoothpasteorfacialcleanser.
PPpolypropyleneiscommonlyfoundinbottlecaps,straws,andmicrowavefoodboxes.
PSpolystyreneisdividedintounfoamedorfoamed.Unfoamedstyrofoamiscommonlyfoundinsomebeverage(suchasYakult)containers;foamed,commonlyknownasstyrofoam,iscommonlyusedinpackagingrubberpellets,disposablethermalinsulationplasticcups,packagingfrozenmeatcontainers,andlunchboxes.
OTHEROtherrecyclableplasticproductsincludepolymethylmethacrylate(PMMA),polycarbonate(PC),polylacticacid(PLA),nylon(Nylon)andglasssteel(FRP),two-wayStretchedpolylacticacidfilm(BOPLA),etc.
Butunfortunately,therecyclingofplasticsisnoteasy,andtheimplementationresultsarenotsatisfactory.Comparedwithmetalrecycling,thebiggestproblemwithplasticrecyclingisthatitisdifficulttoautomaticallysortbymachines,andtheprocessinvolvesalotofmanpower.Inadditiontocontainersthatareusuallymadeofasingleplastic,manyplasticproductsareassembledfromavarietyofdifferentmaterials,andthecostofdisassemblingthemmaybehigherthanthepriceofrecycledplastics.Moreover,sometypesofplasticshavenoeconomicvalueforrecycling,suchasstyrofoam.Thistypeofplasticwasteisusuallyburiedorincinerated.
Atpresent,theproportionofrecycledplasticsintheUnitedStatesisverylow,only5%.
Decomposableplastic
Knives,forksandspoonsmadeofbiodegradablestarchplastic.Mainarticle:Biodegradableplastic
Thedecomposableplasticcandecomposeinthesun.Thereisalsotheadditionofstarchtotheplastictomakeiteasierforbiodegradation,butthedecompositionisstillincomplete.Somepeopleusegeneticallymodifiedbacteriatoproducecompletelybiodegradableplastic,butthecostisstillhigh.GermanBASFcompany(BASF)hasdevelopedabiodegradableplasticcalledEcoflexforfoodpackaging.Theabovedecomposableplasticsarerarelyusedduetocostissues.Theplasticmustbeexposedtoairtodecompose,soifitisburied,itwillstillcausesolidwasteproblems.
Plasticmanufacturersoftenvaguelyrefertoproductsasresinonthepackaging,evenifitisclearlyhumanessence/syntheticresin/syntheticresin.Mostpeoplearesusceptibletobeingmisledintothinkingthatitisanaturalresin,sotheycanbuyanduseitwithconfidence.Manymanufacturersalsodonotclearlylistthevarioushazardouschemicalsthattheyaddtotheirproducts.
Duetothemassproductionofplastics,theircheapprices,andawideselectionofcolors,allpeoplealsouseplasticproductsinlargequantities.Asaresult,theyoftenuseplasticsimproperlywithoutunderstandingtheactualcharacteristicsofcertainplastics.Forexample,someplasticsarenotsuitabletobeheatedorusedtostoreacidicbeveragesandfoods,andsomeplasticsarenotsuitabletobeexposedtosunlight,otherwisetheingredientswillbeunstableandreleased.Becausethereisnoimmediatedanger,variousharmfulsubstancesinplasticproductshaveenteredandpollutedthehumanbodythroughdifferentways,especiallydiet.
Plasticpolyethylene·polyvinylchloride·polystyrene·polyvinylalcohol·polypropylene·polyacrylicacid·polybutylene·polyisobutylene·polysulfone·polyoxymethylene·polyamide·polycarbonate·polyLacticacid·Polytetrafluoroethylene·Polyethyleneterephthalate·Epoxyresin·Phenolicresin·Polyurethane
Syntheticrubberbutadienerubber·styrene-butadienerubber·nitrilerubber·chloroprenerubber
p>
Syntheticfiberpolypropylene·polyester·nylon·acrylic·spandex·vinylon·nylon·dacron·Kevlon
Partdesign
PartdesignmustmeetTherequirementsonthepartmanufacturingsidearealsotruefortheplasticpartsobtainedthroughtheinjectionmoldingprocess.Tomeettherequirementsofproductfunction,qualityandappearance,thedesignofplasticpartsmustmakeinjectionmoldprocessingsimpleandlowcost,andatthesametime,theinjectionmoldingtimeofthepartsisshort,theefficiencyishigh,thepartdefectsarefew,andthequalityishigh.Thisisthedesignforinjectionmolding.Thissectionwillintroducethedesignguidelinesofplasticpartsindetail,sothatthedesignofplasticpartsisadesignforinjectionmolding.
Astheinjectionmoldingprocessinvolvestheproductionofinjectionmolds,thedesignforinjectionmoldingismoreimportant.Theproductionandmodificationofinjectionmoldsaretime-consumingandlaborious.Inthecostofplasticparts,thecostofinjectionmoldsoccupiesalargeproportion.Thecostofasetofmoldsrangesfromtensofthousandstohundredsofthousands.Aftertheinjectionmoldismanufactured,ifthepartdesignismodified,theinjectionmoldneedstobemodifiedaccordingly,whichisboundtoincreasethecostofthemold.Insomecases,becauseofthemoldstructure,theinjectionmoldcannotbemodified,andanewmoldcanonlyberedesignedandmanufactured.Thenthecostandtimelossbroughtaboutisevenmoreunmeasurable.
Commonlyusedsolutions
Thereare9commonsolutionsforplasticspraying:1.Whitefirewine.2.Whiteelectricoil.Three,202potions.Four,207potions.Five,whitewater.6.Getwaterfor303days.7.Getwaterfor333days.Eight,brotherLuofang.9.Cyclohexanone.
Solutionanalysis:
1.Whitefirewine:usedtocleanthesurfacestainsanddisinfectionofplasticparts,andpreventcontactwithmetalduringuse.
2.Whiteelectricoil:usedforcleaningplasticpartsandmetalsurfacestainsandoilstains,anddehydratingcertainplasticparts(chemicallywithHI.ABS).
3,202potion:dissolveHI-typeplasticparts,usedtobondHI-typeplasticpartstodilutetheuniversalglue.
4,207potion:dissolveABSplasticparts,usedtobondABSplasticparts(nochemicaleffectonPP.HDPE).
5.Whiteningwater:removeoilstainsandstains,butithasadestructiveeffectonthestructureofmostplasticparts,causingcracks(nochemicaleffectonPP)
6,303Thinner:Usedfordilutinghardrubberoil.
7,333daystotakewater:usedtodilutesoftrubberoil(PVCwater)todissolvePVCmaterials.
8.GeLuofang:Itdissolvesacrylicmaterial,hasstrongvolatilityandhasanestheticeffect.
9.Cyclohexanone:highboilingpointsolution,strongdissolvingpower,slowdrying,andmoisture-proofeffect.