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Intshayelelo yePolyolefins kunye neFilimu Extrusion

IiPolyolefins, udidi lwemathiriyeli ye-macromolecular eyenziwe kwii-olefin monomers ezifana ne-ethylene kunye nepropylene, zezona plastiki ziveliswa kakhulu kwaye zisetyenziswa kwihlabathi jikelele. Ukuxhaphaka kwazo kuvela kwindibaniselwano ekhethekileyo yeepropathi, kubandakanywa iindleko eziphantsi, ukuqhubekeka okugqwesileyo, uzinzo lwekhemikhali olubalaseleyo, kunye neempawu zomzimba ezilungelelanisiweyo. Phakathi kweendlela ezahlukeneyo zokusetyenziswa kwe-polyolefins, iimveliso zefilimu zibambe indawo ephambili, zisebenza imisebenzi ebalulekileyo ekupakishweni kokutya, ukugqunywa kwezolimo, ukupakishwa kwamashishini, iimveliso zonyango kunye nococeko, kunye nempahla yabathengi bemihla ngemihla. I-polyolefin resins eziqhelekileyo ezisetyenziselwa ukuveliswa kwefilimu ziquka i-polyethylene (PE) - equka i-Linear Low-Density Polyethylene (LLDPE), i-Low-Density Polyethylene (LDPE), kunye ne-High-Density Polyethylene (HDPE) - kunye ne-polypropylene (PP).

Ukwenziwa kweefilimu zepololefin ikakhulu kuxhomekeke kubuchwepheshe be-extrusion, kunye neBlown Film Extrusion kunye neCast Film Extrusion ibe ziinkqubo ezimbini eziphambili.

1. Inkqubo yeFilimu evuthelweyo ye-Extrusion

Ifilimu evuthelweyo extrusion yenye yezona ndlela zixhaphakileyo zokuvelisa iifilimu zepololefin. Umgaqo osisiseko ubandakanya ukukhupha ipholima enyibilikisiweyo ngokuthe nkqo ukuya phezulu ngokufa konyaka, ukwenza iparison enodonga olubhityileyo lwetubula. Emva koko, umoya ocinezelekileyo ungeniswa ngaphakathi kule parini, ubangela ukuba unyukele kwiqamza elinobubanzi obukhulu kunolo lwefa. Njengoko iqamza linyuka, lipholiswa ngenkani kwaye liqiniswe ngumsesane womoya wangaphandle. Iqamza elipholileyo lithi ke ligotywe liqela leerola ze-nip (kaninzi kusetyenziswa isakhelo esidilikayo okanye i-A-frame) kwaye emva koko litsalwe ziirola zokurhuqa phambi kokuba lisondezwe kumqulu. Inkqubo yefilimu evuthelweyo ivelisa iifilimu ezine-biaxial orientation, nto leyo ethetha ukuba babonisa ulungelelwaniso olufanelekileyo lweempawu zoomatshini kuzo zombini isalathiso somatshini (MD) kunye nesalathiso esinqamlezayo (TD), njengamandla okuqina, ukuxhathisa kweenyembezi, kunye namandla empembelelo. Ubungqingqwa befilimu kunye neempawu zoomatshini zingalawulwa ngokulungelelanisa umlinganiselo wokuvuthela (i-BUR - umlinganiselo we-bubble diameter ukuya kwi-diameter yokufa) kunye ne-draw-down ratio (i-DDR - umlinganiselo wesantya sokuthatha ukuya kwi-extrusion speed).

2. Inkqubo ye-Cast Film Extrusion

Ifilimu yeCast extrusion yenye inkqubo ebalulekileyo yokuvelisa iifilimu zepololefin, ezilungele ngakumbi ukwenza iifilimu ezifuna iipropathi eziphezulu zokubona (umzekelo, ukucaca okuphezulu, isicwebezelisi esiphezulu) kunye nokulingana okugqwesileyo kobukhulu. Kule nkqubo, i-polymer etyhidiweyo ikhutshwe ngokuthe tye ngeflethi, i-slot-type T-die, yenza i-web etyhidiweyo efanayo. Le web itsalwa ngokukhawuleza kumphezulu wesantya esiphezulu esinye okanye ngaphezulu, imiqulu epholileyo epholiswe ngaphakathi. Inyibilika yomelela ngokukhawuleza xa idibana nomphezulu obandayo. Iifilimu zeCast ngokubanzi zineempawu ezintle zokubona, imvakalelo ethambileyo, kunye nokutywinwa kobushushu. Ulawulo oluchanekileyo phezu komsantsa womlomo wokufa, iqondo lobushushu le-chill roll, kunye nesantya sokujikeleza kuvumela ukulawulwa ngokuchanekileyo kobunzima befilimu kunye nomgangatho womphezulu.

Top 6 Polyolefin Film Extrusion Imingeni

Ngaphandle kokuvuthwa kwetekhnoloji ye-extrusion, abavelisi bahlala bedibana nothotho lobunzima bokusebenza kwimveliso ebonakalayo yeefilimu ze-polyolefin, ngakumbi xa bezama ukufumana imveliso ephezulu, ukusebenza kakuhle, iigeyiji ezibhityileyo, naxa besebenzisa ii-resin ezintsha zokusebenza okuphezulu. Le miba ayichaphazeli nje kuphela uzinzo lwemveliso kodwa ikwachaphazela ngokuthe ngqo umgangatho wemveliso yokugqibela kunye neendleko. Imingeni ephambili ibandakanya:

1. Melt Fracture (Sharkskin): Le yenye yezona ziphene zixhaphakileyo kwi-polyolefin yefilimu extrusion. I-Macroscopically, ibonakala njengama-ripples anqamlezayo okanye indawo erhabaxa ngokungaqhelekanga kwifilimu, okanye kwiimeko ezimandundu, ukugqwetheka okucacileyo. I-Melt fracture yenzeka ngokuyinhloko xa izinga le-chear ye-polymer inyibilika ephuma kwi-die lidlula ixabiso elibalulekileyo, elikhokelela kwi-oscillations ye-stick-slip phakathi kodonga lokufa kunye ne-bulk inyibilika, okanye xa uxinzelelo olongezelelweyo kwi-exit yokufa ludlula amandla okunyibilika. Esi siphene siphazamisa kakhulu iipropati ezibonakalayo zefilimu (ukucaca, isicwebezelisi), ukugudiswa kwendawo, kwaye kunokunciphisa iimpawu zayo zomatshini kunye nezithintelo.

2. I-Die Drool / Die Build-up: Oku kubhekiselele ekuqokeleleni ngokuthe ngcembe kweemveliso zokuthotywa kwe-polymer, amaqhezu aphantsi obunzima bemolekyuli, izongezo ezisasazwa kakubi (umz., ii-pigments, i-antistatic agents, i-slip agents), okanye i-gels ukusuka kwi-resin kwi-Die lip edges okanye ngaphakathi kwendawo yokufa. Ezi diphozithi ziyakwazi ukukhupha ngexesha lokuvelisa, ukungcolisa umphezulu wefilimu kwaye kubangele iziphene ezifana neegels, i-streaks, okanye i-scratches, ngaloo ndlela ichaphazela ukubonakala kwemveliso kunye nomgangatho. Kwiimeko ezimandundu, ukwakhiwa kokufa kunokuvala indlela yokuphuma, ekhokelela kukwahluka kwegeyiji, ukukrazulwa kwefilimu, kwaye ekugqibeleni kunyanzeliswe ukuvalwa komgca wemveliso ukuze kucocwe ukufa, okukhokelela kwilahleko enkulu ekusebenzeni kakuhle kwemveliso kunye nokuchithwa kwempahla ekrwada.

3. Uxinzelelo oluphezulu lwe-Extrusion kunye nokuguquguquka: Ngaphantsi kweemeko ezithile, ngokukodwa xa kusetyenzwa i-resin high-viscosity okanye usebenzisa izikhewu ezincinci zokufa, uxinzelelo ngaphakathi kwenkqubo ye-extrusion (ngokukodwa kwintloko ye-extruder kunye nokufa) ingaba phezulu kakhulu. Uxinzelelo oluphezulu alunyusi ukusetyenziswa kwamandla kuphela kodwa lubeka umngcipheko kubomi obude besixhobo (umzekelo, isikrufu, umphanda, ukufa) kunye nokhuseleko. Ngaphaya koko, ukuguquguquka okungazinzanga kuxinzelelo lwe-extrusion kubangela ngokuthe ngqo ukwahluka kwimveliso yokunyibilika, okukhokelela kubunzima befilimu obungafaniyo.

4. Umyinge wokuSebenza okuNciniweyo: Ukuthintela okanye ukunciphisa imiba efana nokunyibilika kokwaphuka kunye nokwakhiwa kokufa, abavelisi bahlala benyanzeliswa ukuba banciphise isantya sesikrufu se-extruder, ngaloo ndlela benciphisa imveliso yomgca wemveliso. Oku kuchaphazela ngokuthe ngqo ukusebenza kakuhle kwemveliso kunye neendleko zokwenziwa kweyunithi nganye yemveliso, kwenze ukuba kube nzima ukuhlangabezana neemfuno zentengiso yeefilimu ezinkulu nezinexabiso eliphantsi.

5. Ubunzima bokulawula ukulinganisa: Ukungazinzi kwi-melt flow, ukuhanjiswa kweqondo lokushisa okungafaniyo kwi-die, kunye ne-fae build-up inokufaka isandla kwiinguqu kwi-filimi ubukhulu, zombini kunye ne-longitudinally. Oku kuchaphazela ukusebenza kwefilimu elandelayo kunye neempawu zokusetyenziswa kokuphela.

6. Ukutshintsha kwe-Resin enzima: Xa utshintshela phakathi kweentlobo ezahlukeneyo okanye amabakala e-polyolefin resins, okanye xa uguqula i-masterbatches yombala, izinto ezishiyekileyo ukusuka ekuqhutyweni kwangaphambili kudla nzima ukuhlanjululwa ngokupheleleyo kwi-extruder kunye nokufa. Oku kukhokelela ekudityanisweni kwezinto ezindala nezintsha, ukuvelisa imathiriyeli yotshintsho, ukolula amaxesha okutshintsha, kunye nokwanda kwamazinga okulahlwa.

Le mingeni iqhelekileyo yokusetyenzwa icinezela iinzame zabavelisi befilimu ye-pololefin ukomeleza umgangatho wemveliso kunye nokusebenza kakuhle kwemveliso, kwaye ikwabeke imiqobo ekwamkelweni kwemathiriyeli emitsha kunye nobuchule bokusetyenzwa phambili. Ke ngoko, ukufuna izisombululo ezisebenzayo ukoyisa le mingeni kubalulekile kuphuhliso oluzinzileyo nolusempilweni lweshishini lonke lefilimu ye-polyolefin extrusion.

Izisombululo zePolyolefin Film Extrusion Process: Polymer Processing Aids (PPAs)

I-Polymer Processing Aids (i-PPAs) izongezo ezisebenzayo ezibaluleke kakhulu ekuphuculeni ukuziphatha kwe-rheological ye-polymer iyancibilika ngexesha lokukhupha kunye nokuguqula ukusebenzisana kwabo kunye nomgangatho wezixhobo, ngaloo ndlela boyisa uluhlu lweengxaki zokucubungula kunye nokuphucula ukusebenza kakuhle kwemveliso kunye nomgangatho wemveliso.

1. IiPPA ezisekelwe kwiFluoropolymer

Ubume beMichiza kunye neempawu: ezi ngoku zezona zisetyenziswa ngokubanzi, iteknoloji ekhulileyo, kunye nodidi olusebenzayo olubonakalayo lweePPAs. Ngokwesiqhelo ziihomopolymers okanye ii-copolymers ezisekwe kwi-fluoroolefin monomers ezifana ne-vinylidene fluoride (VDF), i-hexafluoropropylene (HFP), kunye ne-tetrafluoroethylene (TFE), kunye ne-fluoroelastomers yeyona imele. Imixokelelwane yeemolekyuli zezi PPA zityebile kwi-high-bond-energy, i-low-polarity CF bonds, enika iimpawu ezizodwa ze-physicochemical: amandla aphantsi kakhulu aphantsi komhlaba (okufana ne-polytetrafluoroethylene/Teflon®), ukuzinza okugqwesileyo kwe-thermal, kunye nokungangeni kweekhemikhali. Ngokucacileyo, iiPPA zefluoropolymer ngokubanzi zibonisa ukungahambelani kakuhle kunye ne-non-polar polyolefin matrices (njenge-PE, PP). Oku kungahambelani yimfuneko ephambili yokufuduka kwabo okusebenzayo kwiindawo zentsimbi zokufa, apho benza i-lubricating lubricating coating.

Iimveliso eziMmeliyo: Iibrendi eziphambili kwimarike yehlabathi yee-fluoropolymer PPAs zibandakanya uthotho lweChemours' Viton™ FreeFlow™ kunye nothotho lwe-3M's Dynamar™, oluyalela isabelo esibalulekileyo semarike. Ukongezelela, amabakala athile e-fluoropolymer avela kwi-Arkema (uchungechunge lwe-Kynar®) kunye ne-Solvay (i-Tecnoflon®) nayo isetyenziswa njenge, okanye ngamacandelo abalulekileyo kwi-PPA formulations.

2. ISilicone-based Processing Aids (PPAs)

Ubume beMichiza kunye neempawu: Amacandelo asebenzayo aphambili kule klasi yePPAs i-polysiloxanes, ngokuqhelekileyo ebizwa ngokuba yi-silicones. Umqolo we-polysiloxane uqukethe i-silicon kunye ne-athomu ye-oxygen (-Si-O-), kunye namaqela e-organic (ngokuqhelekileyo i-methyl) efakwe kwii-athomu ze-silicon. Olu lwakhiwo lukhethekileyo lwemolekyuli lunika izixhobo ze-silicone ezinoxinzelelo oluphantsi kakhulu lomphezulu, uzinzo oluhle kakhulu lwe-thermal, ukuguquguquka okuhle, kunye neempawu ezingabambeleli kwizinto ezininzi. Ngokufana ne-fluoropolymer PPAs, ii-PPA ezisekelwe kwi-silicone zisebenza ngokufudukela kwiindawo zetsimbi zezixhobo zokucubungula ukwenza i-lubricating layer.

Iimpawu zeSicelo: Nangona i-fluoropolymer PPAs ilawula icandelo lefilimu ye-polyolefin ye-extrusion, ii-PPA ezisekelwe kwi-silicone zinokubonisa iingenelo ezizodwa okanye zenze iziphumo ze-synergistic xa zisetyenziswe kwiimeko ezithile zesicelo okanye ngokubambisana neenkqubo ezithile ze-resin. Umzekelo, zinokuthathelwa ingqalelo kwizicelo ezifuna i-coefficients ephantsi kakhulu yokukhuhlana okanye apho iimpawu ezithile zomphezulu zifunwayo kwimveliso yokugqibela.

Ngaba ujongene nokuBhalwa kweFluoropolymer okanye i-PTFE yoNikezo lweMingeni?

Sombulula imingeni yePolyolefin yokuKhulisa iFilimu ngePFAS-Izisombululo zePPA zasimahla-SILIKE's Fluorine Free Polymer izongezo

I-SILIKE ithatha indlela esebenzayo kunye neemveliso zayo ze-SILIMER, ezibonelela ngezinto ezintshaIi-PFAS-free polymer processing aids (PPAs). Lo mgca wemveliso ugcweleyo une-100% yeePPA ezimsulwa zePFAS,Izongezo zePPA zePolymer ezingenafluorine, kwayePFAS-free & fluorine-free PPA masterbatches.Ngoukuphelisa imfuno yezongezo zefluorine, ezi zixhobo zokulungisa ziphucula kakhulu inkqubo yokuvelisa i-LLDPE, i-LDPE, i-HDPE, i-mLLDPE, i-PP, kunye neenkqubo ezahlukeneyo zefilimu ye-polyolefin extrusion. Bahambelana nemigaqo yamva nje yokusingqongileyo ngelixa bekwanyusa ukusebenza kakuhle kwemveliso, ukunciphisa ixesha lokuphumla, kunye nokuphucula umgangatho wemveliso ngokubanzi. IiPPAs ezingenazi-PFAS zika-SILIKE zizisa izibonelelo kwimveliso yokugqibela, kubandakanya nokupheliswa kokwaphuka okunyibilikayo (isikhumba sikakrebe), ukuguda okuphuculweyo, kunye nomgangatho ophezulu womphezulu.

Ukuba usokola nefuthe lokuvalwa kwe-fluoropolymer okanye ukunqongophala kwe-PTFE kwiinkqubo zakho ze-polymer extrusion, i-SILIKE ibonelelaezinye ii-fluoropolymer PPAs/PTFE, Izongezo zasimahla zePFAS zokwenza ifilimuezilungiselelwe ukuhlangabezana neemfuno zakho, kungekho tshintsho lwenkqubo olufunekayo.