Kev txhaj tshuaj molding yog ib qho ntawm cov txheej txheem tsim khoom siv tau zoo tshaj plaws thiab ua tau zoo rauCov khoom siv PVC (polyvinyl chloride), ua rau muaj peev xwm tsim cov duab nyuaj nrog kev ua kom raug - los ntawm cov khoom siv hauv tsheb thiab cov khoom siv hluav taws xob mus rau cov khoom siv kho mob thiab cov khoom siv hauv tsev. Txawm li cas los xij, PVC cov qauv molecular muaj qhov sib tw tshwj xeeb thaum lub sijhawm ua tiav: nws tsis ruaj khov thaum raug rau qhov kub siab (feem ntau 160–220 ° C) thiab cov zog shear uas muaj nyob hauv kev txhaj tshuaj molding. Yog tsis muaj kev ruaj khov zoo, PVC yuav raug puas tsuaj, ua rau muaj kev hloov pauv (daj lossis xim av), txo cov khoom siv kho tshuab, thiab txawm tias tso tawm cov khoom tsis zoo. Qhov no yog qhov uas PVC stabilizers kauj ruam ua cov phab ej tsis muaj npe, tsis yog tsuas yog tiv thaiv kev puas tsuaj tab sis kuj ua kom zoo dua kev ua haujlwm thiab xyuas kom meej tias cov khoom kawg ua tau raws li cov qauv zoo. Hauv cov blog no, peb yuav dhia mus rau hauv lub luag haujlwm tseem ceeb ntawm PVC stabilizers hauv kev txhaj tshuaj molding, tshawb nrhiav cov hom feem ntau, thiab tshuaj xyuas seb lawv cuam tshuam li cas rau cov txheej txheem ua tiav tseem ceeb thiab kev ua haujlwm kawg ntawm cov khoom.
Yuav kom nkag siab tias vim li cas cov stabilizers tsis tuaj yeem sib tham rau PVC txhaj tshuaj molding, nws yog qhov tseem ceeb ua ntej kom nkag siab txog qhov ua rau PVC tsis ruaj khov. PVC yog ib qho vinyl polymer tsim los ntawm polymerization ntawm vinyl chloride monomers, thiab nws cov saw molecular muaj cov chlorine-carbon bonds tsis muaj zog. Thaum cua sov rau qhov kub uas xav tau rau kev txhaj tshuaj molding, cov bonds no tawg, pib ua rau muaj kev puas tsuaj ntawm cov saw hlau. Cov txheej txheem no, hu ua dehydrochlorination, tso tawm hydrogen chloride (HCl) roj - ib yam khoom corrosive uas ua rau kev puas tsuaj sai dua thiab ua rau cov khoom siv molding puas tsuaj. Tsis tas li ntawd, dehydrochlorination ua rau muaj kev sib txuas ob chav hauv PVC saw hlau, uas ua rau cov khoom siv tig daj, tom qab ntawd xim av, thiab thaum kawg ua brittle. Rau cov neeg txhaj tshuaj molding, qhov no txhais tau tias cov khoom pov tseg, cov nqi kho mob nce ntxiv, thiab tsis ua raws li cov cai kev nyab xeeb thiab zoo. Cov stabilizers cuam tshuam qhov kev puas tsuaj no los ntawm kev nqus HCl, neutralizing acidic byproducts, lossis scavenging free radicals uas tsav cov saw hlau - zoo tiv thaiv PVC thaum lub sijhawm ua thiab txuas ntxiv cov khoom siv lub neej.
Tsis yog txhua tusCov khoom siv PVC stabilizerraug tsim sib npaug, thiab kev xaiv hom zoo rau kev txhaj tshuaj molding nyob ntawm ntau yam: qhov kub thiab txias ua haujlwm, lub sijhawm voj voog, qhov nyuaj ntawm pwm, qhov xav tau ntawm cov khoom kawg (piv txwv li, kev sib cuag zaub mov, kev tiv thaiv UV), thiab cov cai ib puag ncig. Hauv qab no yog kev sib piv ntawm cov hom stabilizer siv dav tshaj plaws hauv kev txhaj tshuaj molding, lawv cov txheej txheem ntawm kev ua haujlwm, thiab cov txiaj ntsig tseem ceeb thiab qhov tsis zoo rau kev siv ua haujlwm:
| Hom Stabilizer | Txoj Haujlwm ntawm Kev Ua Haujlwm | Cov txiaj ntsig ntawm kev txhaj tshuaj molding | Cov kev txwv | Cov Ntawv Thov Ib Txwm Muaj |
| Scavenge HCl thiab tsim cov kev sib txuas ruaj khov nrog PVC saw hlau; tiv thaiv cov saw hlau tawg thiab sib txuas. | Kev ruaj khov kub zoo heev ntawm qhov kub siab; qhov xav tau tsawg dua; qhov cuam tshuam tsawg kawg nkaus rau cov dej yaj; tsim cov khoom meej, xim ruaj khov | Tus nqi siab dua; qee hom txwv tsis pub siv rau hauv kev sib cuag zaub mov lossis kev siv kho mob; tej zaum yuav muaj teeb meem ib puag ncig | Cov khoom PVC ntshiab (piv txwv li, cov kav dej kho mob, cov thawv ntim khoom noj); cov khoom siv tsheb uas muaj kev ua haujlwm siab | |
| Kev ua ob yam: Cov ntsev Ca nqus HCl; cov ntsev Zn tshem tawm cov dawb radicals; feem ntau ua ke nrog cov co-stabilizers (piv txwv li, cov roj epoxidized) | Tus phooj ywg ib puag ncig (tsis muaj hlau hnyav); ua raws li cov cai ntawm cov khoom noj thiab kev kho mob; ua tau zoo rau lub sijhawm ntev | Kev ruaj khov kub qis dua li organotins (zoo tshaj plaws rau 160–190 ° C); tej zaum yuav ua rau me ntsis hloov xim thaum kub siab; xav tau ntau dua koob tshuaj | Cov khoom noj ntim, cov khoom ua si, cov khoom siv kho mob, cov khoom siv hauv tsev | |
| Nqus tau HCl thiab tsim cov tshuaj lead chloride uas tsis yaj tau; muab kev ruaj khov rau lub sijhawm ntev | Kev ruaj khov kub zoo heev; tus nqi qis; kev sib raug zoo nrog PVC; tsim nyog rau kev ua haujlwm kub siab | Tshuaj lom (hlau hnyav); txwv tsis pub siv rau cov khoom siv thiab cov khoom kho mob hauv feem ntau thaj chaw; kev phom sij rau ib puag ncig | Cov kav dej lag luam (hauv cov cheeb tsam tsis raug tswj hwm); cov khoom siv hnyav uas tsis yog rau cov neeg siv khoom | |
| Cov Khoom Siv Barium-Cadmium Stabilizers | Cov ntsev Ba nqus HCl; cov ntsev Cd scavenge cov free radicals; synergistic nyhuv thaum ua ke | Kev ruaj khov kub zoo; xim zoo heev; tsim rau kev txhaj tshuaj PVC uas yoog tau thiab nruj | Cadmium yog lom; txwv tsis pub siv rau feem ntau ntawm cov lag luam thoob ntiaj teb; kev pheej hmoo ntawm ib puag ncig thiab kev noj qab haus huv | Cov ntawv thov qub (theem tshem tawm hauv feem ntau thaj chaw); qee cov khoom lag luam tsis yog rau cov neeg siv khoom |
Hauv kev tswj hwm niaj hnub no, cov thawj coj thiabCov khoom ruaj khov Ba-CdFeem ntau tau raug tshem tawm mus rau lwm txoj hauv kev los hloov cov organotin thiab Ca-Zn, tshwj xeeb tshaj yog rau cov khoom siv rau cov neeg siv khoom thiab cov khoom kho mob. Rau cov neeg txhaj tshuaj pwm, qhov kev hloov pauv no txhais tau tias yuav tsum hloov kho rau cov yam ntxwv tshwj xeeb ntawm cov khoom ruaj ntseg no - piv txwv li, kho qhov kub lossis lub sijhawm voj voog kom haum rau Ca-Zn qhov kev ruaj khov cua sov qis dua, lossis sib npaug tus nqi nrog kev ua tau zoo thaum siv organotins.
Qhov cuam tshuam ntawm cov stabilizers rau PVC ua haujlwm hauv kev txhaj tshuaj molding txuas ntxiv mus deb tshaj qhov tsuas yog tiv thaiv kev puas tsuaj xwb. Nws ncaj qha cuam tshuam rau cov txheej txheem ua haujlwm tseem ceeb xws li cov ntsuas dej ntws, lub sijhawm voj voog, kev sau pwm, thiab kev siv zog - txhua yam uas cuam tshuam rau kev ua haujlwm zoo thiab qhov zoo ntawm ib feem. Cia peb rhuav tshem cov teebmeem no nrog lub ntiaj teb tiag tiag: kev ntws yaj, piv txwv li, yog qhov tseem ceeb rau kev ua kom ntseeg tau tias PVC compound sau cov pwm sib xyaw ua ke thiab tsis muaj qhov tsis zoo xws li kev txhaj tshuaj luv luv lossis cov kab vuam. Organotin stabilizers, vim lawv cov koob tshuaj tsawg thiab kev sib raug zoo zoo nrog PVC, muaj qhov cuam tshuam tsawg kawg nkaus rau MFI, tso cai rau cov yaj kom ntws zoo txawm tias los ntawm cov ntu nyias nyias lossis cov duab geometries.Cov tshuaj stabilizer Ca-Zn, ntawm qhov tod tes, tej zaum yuav ua rau melt viscosity me ntsis (tshwj xeeb tshaj yog thaum noj ntau dua), yuav tsum tau cov pwm kho qhov siab lossis qhov kub kom tswj tau qhov ntws zoo tshaj plaws. Qhov no yog qhov tseem ceeb uas yuav tsum xav txog thaum hloov ntawm organotins mus rau Ca-Zn rau kev ua raws li txoj cai - kev hloov me me rau cov txheej txheem ua tiav tuaj yeem ua qhov sib txawv loj hauv qhov zoo ntawm ib feem.
Lub sijhawm voj voog yog lwm yam tseem ceeb rau cov neeg txhaj tshuaj pwm, vim nws cuam tshuam ncaj qha rau kev tsim khoom. Cov khoom ruaj khov uas muaj kev ruaj khov kub, xws li organotins lossis lead (txawm tias tam sim no txwv), tso cai rau lub sijhawm voj voog luv dua los ntawm kev ua kom muaj qhov kub siab dua yam tsis muaj kev puas tsuaj. Qhov kub siab dua txo cov viscosity yaj, ua kom pwm puv sai dua, thiab luv lub sijhawm txias - txhua yam uas ua rau muaj kev tsim khoom ntau dua. Ntawm qhov tod tes, cov khoom ruaj khov uas muaj kev ruaj khov kub qis dua, xws li Ca-Zn, yuav xav tau lub sijhawm voj voog ntev dua kom tsis txhob kub dhau, tab sis qhov kev pauv pauv no feem ntau yog qhov tseeb los ntawm lawv cov txiaj ntsig ib puag ncig thiab kev ua raws li txoj cai. Cov neeg pwm tuaj yeem txo qhov no los ntawm kev ua kom zoo dua lwm yam kev ntsuas, xws li siv cov tswj kub pwm lossis kho qhov ceev ntawm lub hau ntswj kom txo qhov cua sov uas ua rau shear.
Kev ruaj khov ntawm kev txiav kuj yog qhov tseem ceeb uas yuav tsum xav txog, tshwj xeeb tshaj yog rau cov txheej txheem txhaj tshuaj uas muaj kev ceev ceev ntawm cov ntsia hlau. Cov zog txiav tsim cov cua sov ntxiv rau hauv PVC yaj, ua rau muaj kev pheej hmoo ntawm kev puas tsuaj. Cov khoom ruaj khov uas tuaj yeem tiv taus kev txiav siab - xws li organotins thiab kev sib xyaw ua ke Ca-Zn ua tau zoo - pab tswj kev ruaj khov ntawm kev yaj hauv qab cov xwm txheej no, tiv thaiv kev hloov pauv thiab ua kom muaj cov khoom sib xws. Qhov sib piv, cov khoom ruaj khov tsis zoo yuav tawg hauv qab kev txiav siab, ua rau cov dej yaj tsis sib xws thiab cov qhov tsis zoo xws li cov qhov tsis zoo ntawm qhov chaw lossis kev ntxhov siab sab hauv.
Kev ua tau zoo ntawm cov khoom kawg yog nyob ntawm seb koj xaiv cov stabilizer twg. Piv txwv li, cov khoom siv PVC sab nraum zoov (piv txwv li, rooj tog vaj, sab nraud cladding) xav tau cov stabilizers uas tiv taus UV kom tiv thaiv kev puas tsuaj los ntawm lub hnub ci. Ntau Ca-Zn thiab organotin stabilizers tuaj yeem tsim nrog UV absorbers lossis hindered amine light stabilizers (HALS) los txhim kho kev nyab xeeb ntawm huab cua. Rau cov khoom siv PVC ruaj khov xws li cov yeeb nkab fittings lossis cov khoom siv hluav taws xob, cov stabilizers uas txhim kho lub zog cuam tshuam thiab qhov ntev ruaj khov yog qhov tseem ceeb. Organotins, tshwj xeeb, paub txog kev khaws cov khoom siv kho tshuab ntawm PVC ruaj khov thaum lub sijhawm ua tiav, xyuas kom meej tias cov khoom tuaj yeem tiv taus kev ntxhov siab thiab tswj lawv cov duab dhau sijhawm.
Cov ntawv thov rau kev sib cuag zaub mov thiab kev kho mob xav tau cov stabilizers uas tsis muaj tshuaj lom thiab ua raws li cov qauv thoob ntiaj teb. Ca-Zn stabilizers yog tus qauv kub ntawm no, vim lawv tsis muaj hlau hnyav thiab ua tau raws li cov kev cai nyab xeeb nruj. Organotins kuj siv rau hauv qee daim ntawv thov kev sib cuag zaub mov, tab sis tsuas yog cov hom tshwj xeeb (piv txwv li, methyltin, butyltin) uas tau pom zoo rau kev siv zoo li no. Cov pwm ua haujlwm hauv cov haujlwm no yuav tsum ua tib zoo xyuas seb lawv cov qauv stabilizer puas ua raws li cov teeb meem kev cai lij choj thiab xyuas kom meej tias cov neeg siv khoom muaj kev nyab xeeb.
Thaum xaiv ib qhoPVC stabilizer rau kev txhaj tshuaj molding, muaj ntau yam kev xav txog kev siv tau uas yuav tsum nco ntsoov tshaj li hom thiab kev ua tau zoo xwb. Kev sib haum xeeb nrog lwm cov khoom ntxiv yog qhov tseem ceeb heev—PVC cov tshuaj feem ntau muaj cov yas, cov roj nplua nyeem, cov khoom sau, thiab cov xim, thiab lub stabilizer yuav tsum ua haujlwm sib koom tes nrog cov khoom no. Piv txwv li, qee cov roj nplua nyeem tuaj yeem txo qhov ua tau zoo ntawm cov stabilizers los ntawm kev tsim ib qho kev thaiv ntawm lub stabilizer thiab PVC matrix, yog li cov pwm yuav tsum tau kho cov roj nplua nyeem lossis xaiv lub stabilizer uas muaj kev sib haum xeeb zoo dua. Kev siv tshuaj yog lwm qhov tseem ceeb: kev siv cov stabilizer tsawg dhau yuav ua rau tsis muaj kev tiv thaiv thiab kev puas tsuaj txaus, thaum siv ntau dhau tuaj yeem ua rau tawg paj (qhov twg lub stabilizer tsiv mus rau qhov chaw ntawm qhov) lossis txo cov khoom siv kho tshuab. Feem ntau cov chaw tsim khoom stabilizer muab cov tshuaj pom zoo raws li hom PVC (rigid vs. flexible) thiab cov xwm txheej ua haujlwm, thiab nws yog ib qho tseem ceeb kom ua raws li cov lus qhia no thaum ua qhov kev sim khiav kom ua tau zoo tshaj plaws.
Cov qauv ib puag ncig thiab kev cai lij choj kuj tseem tab tom tsim lub neej yav tom ntej ntawm PVC stabilizers rau kev txhaj tshuaj molding. Kev thawb thoob ntiaj teb rau kev ruaj khov tau ua rau muaj kev thov ntau ntxiv rau cov bio-based lossis biodegradable stabilizers, txawm hais tias cov no tseem nyob rau theem pib ntawm kev txhim kho. Tsis tas li ntawd, cov cai txwv tsis pub siv qee yam tshuaj (piv txwv li, REACH hauv EU) tab tom tsav tsheb tsim kho tshiab hauv kev nyab xeeb dua, cov qauv zoo rau ib puag ncig. Cov neeg pwm yuav tsum paub txog cov qauv no kom ntseeg tau tias lawv cov txheej txheem tseem ua raws li txoj cai thiab sib tw. Piv txwv li, hloov mus rau Ca-Zn stabilizers tam sim no tuaj yeem pab zam kev cuam tshuam yog tias cov cai nruj dua ntawm organotins raug siv yav tom ntej.
Yuav kom piav qhia txog qhov cuam tshuam tiag tiag ntawm kev xaiv cov stabilizer, cia peb xav txog ib qho kev tshawb fawb: ib lub tuam txhab pwm uas tsim cov thawv hluav taws xob PVC ruaj khov los ntawm kev txhaj tshuaj molding tau ntsib teeb meem daj ntawm cov khoom thiab cov khoom seem ntau heev. Kev tshawb nrhiav thawj zaug qhia tau tias lub tuam txhab pwm siv cov stabilizer Ba-Cd pheej yig, uas tsis yog tsuas yog tsis ua raws li EU cov cai xwb tab sis kuj tsis tiv thaiv PVC tsis txaus ntawm qhov kub siab (200 ° C) uas xav tau rau kev tsim pwm nyuaj. Tom qab hloov mus rau cov stabilizer organotin ua haujlwm siab, qhov teeb meem daj tau raug tshem tawm, cov khoom seem poob qis 35%, thiab cov khoom ua tau raws li EU cov qauv kev nyab xeeb. Lub tuam txhab pwm kuj pom tias cov dej yaj zoo dua, uas txo qhov siab txhaj tshuaj thiab luv lub sijhawm voj voog los ntawm 10%, ua rau muaj kev tsim khoom ntau ntxiv. Hauv lwm qhov piv txwv, ib lub tuam txhab tsim cov thawv PVC zaub mov tau hloov los ntawm organotins mus rau Ca-Zn stabilizer kom ua tau raws li FDA cov cai. Txawm hais tias lawv yuav tsum tau kho qhov kub ntawm kev ua haujlwm me ntsis (txo nws ntawm 195 ° C mus rau 185 ° C) kom tswj tau qhov ruaj khov, lub qhov hloov pauv tau yooj yim nrog qhov cuam tshuam tsawg kawg nkaus rau lub sijhawm voj voog, thiab cov khoom tseem khaws cia lawv qhov meej thiab cov khoom siv kho tshuab.
Cov tshuaj stabilizer PVC yog qhov tseem ceeb rau kev txhaj tshuaj molding kom zoo, ua haujlwm ua ob qho tib si tiv thaiv kev puas tsuaj thiab ua kom muaj kev ua haujlwm zoo tshaj plaws. Kev xaiv cov tshuaj stabilizer - txawm tias organotin, Ca-Zn, lossis lwm hom - yuav tsum tau ua raws li cov xwm txheej ua haujlwm tshwj xeeb, cov kev xav tau kawg ntawm cov khoom, thiab cov kev txwv ntawm txoj cai. Cov neeg ua pwm uas siv sijhawm los xaiv cov tshuaj stabilizer zoo thiab ua kom zoo dua cov txheej txheem ua haujlwm raws li qhov kev xaiv ntawd yuav tau txais txiaj ntsig los ntawm cov nqi pov tseg qis dua, kev tsim khoom ntau dua, thiab cov khoom zoo uas ua tau raws li cov qauv kev nyab xeeb thiab kev ua tau zoo. Thaum kev lag luam txuas ntxiv mus rau kev ruaj khov thiab cov cai nruj dua, kev paub txog cov thev naus laus zis stabilizer tshiab thiab cov qauv yuav yog qhov tseem ceeb rau kev tswj hwm kev sib tw. Txawm hais tias koj tab tom tsim cov khoom PVC khov kho lossis hloov pauv tau, rau cov neeg siv khoom lossis kev siv hauv kev lag luam, cov tshuaj stabilizer zoo yog lub hauv paus ntawm kev txhaj tshuaj molding kom zoo.
Lub sijhawm tshaj tawm: Lub Ib Hlis-29-2026