PVC yas yog synthesized los ntawm acetylene roj thiab hydrogen chloride, thiab ces polymerized.Thaum ntxov xyoo 1950, nws tau tsim los ntawm acetylene carbide txoj kev, thiab nyob rau hauv lub lig 1950s, nws tig mus rau ethylene oxidation txoj kev nrog txaus raw khoom thiab tus nqi qis;Tam sim no, ntau tshaj 80% ntawm PVC resins nyob hauv lub ntiaj teb no yog tsim los ntawm txoj kev no.Txawm li cas los xij, tom qab xyoo 2003, vim cov nqi roj nce siab, tus nqi ntawm acetylene carbide txoj kev yog li 10% qis dua li ntawm ethylene oxidation txoj kev, yog li cov txheej txheem synthesis ntawm PVC tig mus rau acetylene carbide txoj kev.
PVC yas yog polymerized los ntawm cov kua vinyl chloride monomer (VCM) los ntawm kev ncua, tshuaj pleev ib ce, bulk los yog tov txheej txheem.Cov txheej txheem ncua kev kawm ntawv polymerization tau yog txoj hauv kev tseem ceeb los tsim PVC cob nrog cov txheej txheem tsim khoom, kev ua haujlwm yooj yim, cov nqi tsim khoom tsawg, ntau yam khoom thiab ntau yam kev thov.Nws suav txog li 90% ntawm lub ntiaj teb cov khoom siv PVC (homopolymer kuj suav txog li 90% ntawm lub ntiaj teb cov khoom siv PVC tag nrho).Qhov thib ob yog txoj kev pleev xim, uas yog siv los tsim PVC muab tshuaj txhuam.Cov tshuaj tiv thaiv polymerization yog pib los ntawm cov dawb radicals, thiab cov tshuaj tiv thaiv kub yog feem ntau 40 ~ 70oc.Cov tshuaj tiv thaiv kub thiab cov concentration ntawm cov neeg pib muaj kev cuam tshuam zoo rau ntawm tus nqi polymerization thiab qhov hnyav molecular faib ntawm PVC resin.
Quav daim ntawv qhia xaiv
Cov mis ntawm PVC yas profile feem ntau yog tsim los ntawm PVC resin thiab additives, uas tau muab faib ua: tshav kub stabilizer, lubricant, processing modifier, impact modifier, muab tub lim, anti-aging agent, colorant, thiab lwm yam. Ua ntej tsim PVC formula, peb yuav tsum xub ua ntej nkag siab txog kev ua tau zoo ntawm PVC cob thiab ntau yam additives.
1. Cov resin yuav tsum yog pvc-sc5 resin los yog pvc-sg4 resin, uas yog, PVC resin nrog polymerization degree ntawm 1200-1000.
2. Thermal stability system yuav tsum tau ntxiv.Xaiv raws li qhov yuav tsum tau ua tiag tiag, thiab xyuam xim rau cov nyhuv synergistic thiab antagonistic nyhuv ntawm cov cua sov stabilizers.
3. Kev hloov pauv yuav tsum tau ntxiv.CPE thiab ACR cuam tshuam hloov pauv tuaj yeem xaiv.Raws li lwm cov khoom xyaw hauv cov mis thiab lub peev xwm ntawm lub tshuab extruder, qhov sib ntxiv yog 8-12 feem.CPE muaj tus nqi qis thiab ntau qhov chaw;ACR muaj kev laus ua haujlwm siab thiab lub zog fillet.
4. Ntxiv cov nqi tsim nyog rau hauv lub tshuab lubrication.Lub tshuab lubrication tuaj yeem txo qhov load ntawm cov tshuab ua haujlwm thiab ua kom cov khoom du, tab sis ntau dhau yuav ua rau lub zog ntawm vuam fillet txo.
5. Ntxiv kev hloov kho tuaj yeem txhim kho cov yas zoo thiab txhim kho cov khoom zoo.Feem ntau, ACR kev hloov kho yog ntxiv rau ntawm 1-2 ntu.
6. Ntxiv cov muab tub lim tuaj yeem txo tus nqi thiab ua kom cov rigidity ntawm qhov profile, tab sis nws muaj kev cuam tshuam zoo rau lub zog ntawm qhov kub thiab txias.Reactive lub teeb calcium carbonate nrog siab fineness yuav tsum tau ntxiv, nrog rau qhov ntxiv ntawm 5-15 qhov chaw.
7. Ib qho nyiaj ntawm titanium dioxide yuav tsum tau ntxiv los tiv thaiv ultraviolet rays.Titanium dioxide yuav tsum yog hom rutile, nrog rau qhov sib ntxiv ntawm 4-6 qhov chaw.Yog tias tsim nyog, ultraviolet absorbers UV-531, uv327, thiab lwm yam tuaj yeem muab ntxiv los ua kom cov laus tiv thaiv ntawm qhov profile.
8. Ntxiv xiav thiab fluorescent brightener hauv qhov tsim nyog tuaj yeem txhim kho cov xim ntawm qhov profile.
9. Cov mis yuav tsum tau yooj yim kom deb li deb tau, thiab cov kua additives yuav tsum tsis txhob muab ntxiv kom deb li deb tau.Raws li cov kev xav tau ntawm cov txheej txheem sib tov (saib qhov teeb meem sib xyaw), cov qauv yuav tsum muab faib ua cov khoom siv I, khoom II thiab cov khoom siv III hauv cov khoom siv raws li kev noj zaub mov, thiab ntim raws li.
Folded suspension polymerization
Suspension polymerization ua rau tib lub cev cov kua dej uas raug tshem tawm hauv dej los ntawm kev nplawm tas li, thiab cov tshuaj tiv thaiv polymerization yog nqa tawm hauv cov dej me me monomer.Feem ntau, suspension polymerization yog intermittent polymerization.
Nyob rau hauv xyoo tas los no, tuam txhab uas muag tau kawm thiab txhim kho cov mis, polymerizer, khoom ntau yam thiab zoo ntawm intermittent suspension polymerization txheej txheem ntawm PVC resin, thiab tsim cov txheej txheem technologies nrog lawv tus kheej yam ntxwv.Tam sim no, Geon lub tuam txhab (lub tuam txhab qub BF Goodrich) thev naus laus zis, shinyue tuam txhab thev naus laus zis hauv Nyij Pooj thiab EVC tuam txhab thev naus laus zis hauv Tebchaws Europe tau siv dav.Cov thev naus laus zis ntawm peb lub tuam txhab no suav txog li 21% ntawm lub ntiaj teb tshiab PVC resin tsim muaj peev xwm txij li xyoo 1990.
Post lub sij hawm: Lub Xya hli ntuj-15-2022