Dab tsi yog qhov txawv ntawm tus tsiaj thiab PetG?

Xuas, ib lub cev polycondensate, yog siv feem ntau hauv cov zaub mov ntim khoom noj thiab cov ntaub ntawv textile, ntawm lwm yam kev siv. Nws yog tam sim no nce siv raws li lub ntim khoom, tsis yog tsuas yog nyob rau hauv cov dej fwj, tab sis kuj nyob rau hauv amorphous tsiaj (apet), crystalline cov kaus poom (Crystall) thiab daim hlau. Hauv tsib xyoos dhau los, Engineering-Ady Tsiaj thiab cov khoom siv copolyesters, raws li cov khoom siv polymer, tau siv hauv engineering thiab cov ntaub ntawv ntim tau tshwj xeeb, feem.
Kev ua tiav ntawm tus tsiaj nyob rau hauv cov dej qab zib yog vim nws cov kev ua kom nruj thiab muaj peev xwm ua tau zoo, thiab kev txhim kho ntawm cov tshuab hluav taws xob siab. Cov kaus poom cov kaus poom yog lub teeb yuag, cov kws sib cav sib ceg, rov siv dua, thiab muaj cov huab cua zoo. Lub rwb 2-litre pu pas dej haus cawv yog 24% sib dua dua li lub raj mis lub raj mis zoo sib xws; Lub raj mis khoob nyhav 1/10 ntawm lub khob iav ntawm tib qho loj. Qhov no cawm kev ua haujlwm, lub zog, thiab cov nqi rau txhua qhov txuas ntawm cov chaw tsim khoom rau cov neeg siv khoom.
Chemistry thiab thaj chaw

PET rau dej qab zib fwj yog tsim los ntawm Terephthalic acid (Tpa) tau los ntawm oxidation ntawm P-Xylene. Terephthalic acid yog purified lossis reased nrog Methanol los ua DeFethyl terephthalate (dmt), lossis ntxiv oxidized terephthalic acid (PTA). Lwm qhov yooj yim raw rau cov tsiaj yog kev tawm tsam, uas hloov dua siab tshiab rau ethylene glycol (piv txwv li) los ntawm cov tshuaj tiv thaiv. PET is a condensation polymer formed by the continuous polymerization of DMT (or PTA) and EG in the molten state, and then a solid-state polymerization process to obtain large crystals and the final molecular weight and intrinsic viscosity. Cov txheej txheem-lub xeev ua rau cov ntsiab lus ethanol ntawm cov polymer muaj tsawg.

General Commerpial tsiaj resin melts ntawm txog 480F (), tab sis lub ntsiab lus melting ntawm cov tsiaj siab yog li 520f ().

Oriented Crystallized Tsiaj muaj lub zog zoo. Tougness thiab pob tshab, thiab tiv taus cov kua qaub tsis muaj zog, hauv paus thiab ntau cov kuab tshuaj.

Cov qeb tshwj xeeb

Stretch tshuab moulding qib tsiaj tuaj yeem muab cov xim tawv, ntsuab thiab lub teeb daj. Cov xim xim polymer hauv cov reactor tsis tas yuav compounded nrog cov kev tsis zoo ntawm cov khoom siv lub cev, thiab txhim kho cov xim sib dhos. Cov khoom siv ntshiab ntawm cov viscosic ntau yam muaj. MET copolymers crystallize qeeb, uas tso cai rau lawv los tsim cov dej qab zib zoo li cov khoom siv ntau tshaj qhov kev ua. Extrusion tshuab pwm pwm loj kuj tseem muaj. Cov khoom siv no sib xyaw ua ke ntawm cov zoo melt lub zog thiab qeeb qeeb crystallization, thiab tuaj yeem ua tau yooj yim ntawm cov khoom siv haum haum pwm. Ntau qhov kev txhawb nqa, nplaim taws retardant thiab lwm cov polymers tshwj xeeb tau ua tas li los qhia lossis hloov kho kom tau raws li cov ntawv thov tshiab.

NplaimCopolyester yog lwm qhov piv txwv ntawm cov lej loj ntawm copolyesters. Tsis zoo li PCTA, uas tau hloov kho nrog acid, petg yog diol-hloov polymer ua los ntawm kev sib xyaw ua ke ntawm CHDM Diol nrog TPA (Terhylalic Glycolol. Petg copolymers tuaj yeem ua pwm los yog extruded thiab feem ntau nyob twj ywm amorphous, pob tshab thiab muaj tsis muaj kob, txawm tias muaj kev sib cav sib ceg.

Nws muaj siab tawv, hardness thiab zoo tougnness, txawm tias tsis kub. Kev sib xyaw ua ke ntawm pob tshab, kev ua kom nruj thiab muaj zog rau kev txhaj tshuaj moulding, tshuab moulding thiab extrusion ntawm profiles, kav dej, zaj duab xis thiab cov ntawv qhia. Petg muaj nyob hauv daim ntawv tsis muaj npe lossis nrog ntau yam ntxiv, nrog rau kev tso tawm cov neeg sawv cev, masterbatches, thiab cuam tshuam kev txhaj tshuaj molding.

Petg yuav tsum tau qhuav ntawm 120-160F txog li 4-6 teev ua ntej molding lossis extrusion. Hauv ob qho txheej txheem, cov txiv hmab kub melt kub li ntawm 420f mus rau 510f. Lub sijhawm tuav lub sijhawm ua cov cuab yeej ua haujlwm ntawm cov kev kub siab dua yuav tsum tau sai li sai tau los tiv thaiv kev ua phem ntau dhau. Kev txhaj tshuaj molding yuav tsum tau ua rau ntawm kev txhaj tshuaj molding tshuab, uas xav tau txhua qhov txhaj tshuaj kom yog 50% rau 80% ntawm nws lub peev xwm.

Petg yuav raug muab tso tawm thiab tshuab pwm ntawm yaj kub yaj ntawm 400f los ua cov tshuaj zawv plaub hau, cov khoom siv huv, thiab cov ntxhia ntim. Cov ntaub ntawv no ua tau raws FDA cov qauv kev sib cuag nrog zaub mov.

Extrusion tuaj yeem tsim tau ntau yam ntawm profiles, thiab raws li lub hnab ntim, cov yeeb yaj kiab, thiab cov ntawv txheeb, ntim khoom siv tshuaj kho mob. Petg thiab Pcta tuaj yeem ua kom tsis muaj kuab nrog ethylene oxide thiab y rays.

Thaum siv rau kev txhaj tshuaj molding, petg feem ntau yog cov txheej txheem ntawm melt kub ntau ntawm 450-510f, nrog pwm kub txog li 70-130F. Cov ntawv thov tam sim no suav nrog cov twj paj nruag, tshuab cov thaiv, ntim cov khoom siv kom pleev ib ce, cov khoom siv ua kom pom thiab khoom ua si.

Tus tsiaj yog tsuas yog siv nyob rau hauv dej qab zib thiab haus dej muag. Tus tsiaj muaj ze li 100% ntawm 2-liter ntim tsis-rov ua dua tshiab ua lag luam, thiab 1.5-litre, 0.5-litre tsiaj fwj kuj tau pom dav dav.

Tsiaj siv hauv zaub mov, dej cawv, xab npum. Thov kom tus tsiaj yuav tsum tau loj hlob ntxiv rau cov dej haus tsis muaj kev siv tau thiab ntim khoom. Cov zaub mov ntim muaj xws li mustard, cov khoom lag luam roj hmab, cov txiv laum huab xeeb, cov khoom nyiam, ua noj kua txiv, cov kua txiv hmab txiv ntoo thiab muaj kua txiv ntau. Cov xim tshiab, tshwj xeeb tshaj yog cov cheer xim, yog cov neeg nyiam ntim khoom ntawm cov tshuaj, cov vitamins thiab dej paug.

Ib qho ntawm cov khoom siv tshiab tshaj plaws thiab nrawm tshaj plaws rau cov tsiaj ntim yog cov khoom noj lossis dej haus ntim, uas yuav tsum tau ntim ntau. Ntau cov zaub mov, tshwj xeeb yog cov txiv hmab txiv ntoo lossis cov khoom noj lossis dej haus nrog cov ntsiab lus txiv hmab txiv ntoo zoo, yuav tsum tau ntim ntawm 180f lossis siab dua. Qhov no muab pasteurization (kom tsis muaj menyuam) ntawm cov khoom thiab thawv thaum lub sijhawm txhaws. Cov khoom siv txhawb nqa tau, xws li lub hnab rau dej qab zib thiab dej qab zib, zoo li yog qhov txias thiab tsis txias tshaj 160F, uas yog vim qee qhov kev txom nyem so kom txaus. Kev ntxhov siab ntxhov siab yog tsim los thaum lub zog moulding ntawm lub thawv. Cov thev naus laus zis tau tsim los txhim kho lub sijhawm kub ua kom muaj zog thaum ua, feem ntau hu ua "kev teeb tsa thaum tshav kub". Ua raws li cov thev naus laus zis tshwj xeeb, muaj cov tswv yim thev naus laus zis, raws li cov khoom ntim uas tsim nyog rau txhaws ntawm 190-195F tuaj yeem tsim tawm. Cov khoom lag luam uas yuav tsum tau ntim nrog cov xeeb ceem no suav nrog cov kua txiv ntshiab. Cov dej haus zoo, teas, qee yam dej haus yog cov kua zaub ua si, cov kua txiv, cov tshuaj me me.

Lwm qhov kawg siv ntawm tus tsiaj yog siv dav hauv extrusion txheej thiab extrusion zaj duab xis thiab ntawv. Tsiaj yog siv los ua ib qho kev txuas ntxiv txheej cov khoom siv rau cub muab ntim. Ntxiv rau, crystalline tsiaj (CPET) tuaj yeem siv ua cov khoom siv me me los ua cov tais ci.

Tsiaj zaj duab xis feem ntau yog biaxouse oriented thiab siv li xas duab thiab lwm yam yeeb yaj kiab duab, cov paib hluav taws xob, cov paib hluav taws xob, cov paib ntim thiab ntim fwj. Tus tsiaj tseem siv raws li muaj cov ntaub nplaum theej ntaub ntawv. Tsis-crystalline, unoriented tsiaj zaj duab xis thiab daim ntawv yog pib siv rau kev sau cov thawv ntim, cov khoom lag luam, khob khob noom.

Cov ntsiab lus: PetG yog qhov hloov kho ntawm tus tsiaj, nrog siab dua pob tshab, muaj zog tiv, thiab tau muaj tus nqi siab dua.