Thermal stabilizers
Thermal stabilizers yuav tsum tiv thaiv los yog alleviate lub decomposition ntawm PVC resin. Kev xaiv ntawm thermal stabilizer ntau yam nyob rau hauv formulation feem ntau yog nyob ntawm qhov yuav tsum tau ntawm cov khoom. Piv txwv li:
Lead ntsev stabilizers yog siv nyob rau hauv cov khoom nruj. Lead ntsev stabilizers muaj thermal stability zoo, hluav taws xob zoo heev, thiab tus nqi qis. Txawm li cas los xij, lawv yog cov tshuaj lom heev, ua rau cov khoom tsis huv, thiab tuaj yeem tsim cov khoom tsis zoo.
Nyob rau hauv xyoo tas los no, cov stabilizers sib xyaw tau tshwm sim hauv cov neeg coob, ua rau muaj kev pheej hmoo ntawm kev hloov ib qho khoom stabilizers. Cov yam ntxwv ntawm cov stabilizers muaj xws li muaj zog tshwj xeeb, muaj kuab paug tsawg, thiab ua kom yooj yim rau kev tsim khoom lag luam. Txawm li cas los xij, vim tsis muaj cov qauv kev sib koom ua ke, qhov sib txawv ntawm cov stabilizers los ntawm ntau lub tuam txhab yog qhov tseem ceeb.
Barium-cadmium stabilizers yog ib hom thermal stabilizer nrog kev ua haujlwm zoo. Lawv tau siv dav hauv PVC zaj duab xis ua liaj ua teb. Feem ntau, barium-cadmium zinc thiab organic phosphates yog siv ua ke nrog antioxidants.
Calcium-zinc stabilizers tuaj yeem ua cov khoom tsis muaj tshuaj lom neeg siv hauv ntim khoom noj, khoom siv kho mob, thiab ntim tshuaj. Txawm li cas los xij, lawv qhov kev ruaj ntseg yog qhov tsawg, thiab thaum siv ntau ntau, pob tshab txo qis, thiab lawv nquag frosting.
Organotin stabilizers muaj kev ua tau zoo thiab tsim nyog rau ob qho tib si PVC tawv thiab pob tshab khoom. Tshwj xeeb tshaj yog, octyltin tau dhau los ua ib qho tseem ceeb stabilizer rau cov khoom ntim tsis muaj tshuaj lom, txawm tias tus nqi siab dua.
Epoxy stabilizers feem ntau yog siv los ua cov stabilizers. Thaum siv nrog barium-cadmium thiab calcium-zinc stabilizers, lawv tuaj yeem txhim kho lub teeb thiab kub stability. Txawm li cas los xij, lawv muaj feem cuam tshuam rau kev tsiv teb tsaws chaw. Lwm cov kev pabcuam stabilizers suav nrog polyols thiab organic phosphates.
Nyob rau hauv xyoo tas los no, tsis tshua muaj lub ntiaj teb stabilizers thiab hydrotalcite-based stabilizers kuj tau tshwm sim. Tsis tshua muaj lub ntiaj teb stabilizers yog tus cwj pwm los ntawm kev ua tau zoo heev, thaum hydrotalcite yog ib qho tsis muaj tshuaj lom stabilizer.
Cov Ntsiab Cai ntawm Kev Xaiv Thermal Stabilizer
Nyob rau hauv lub formulation ntawm nruj PVC, thaum lub plasticizer cov ntsiab lus yog tsawg los yog tsis tuaj, tus nqi ntawm stabilizer yuav tsum tau correspondingly nce kom ua tau zoo stability.
(1) Opaque rigid khoom feem ntau siv tribasic lead sulfate thiab dibasic lead phosphite, nrog ib tug synergistic nyhuv thaum siv ua ke nyob rau hauv ib tug ratio ntawm 2: 1 los yog 1: 1, nrog rau tag nrho ntxiv ntawm 3 mus rau 5 qhov chaw. Xwb, cov khoom siv lead ua stabilizers feem ntau siv niaj hnub no.
(2) Rau cov khoom lag luam pob tshab, cov ntsev ntsev tsis siv. Hloov chaw, hlau xab npum stabilizers uas tsis yog Pb thiab Ca, nrog rau cov organic tin, organic antimony, thiab tsis tshua muaj lub ntiaj teb stabilizers, feem ntau xaiv. Hlau xab npum stabilizers yog ntxiv nyob rau hauv ntau ntawm 3 mus rau 4 qhov chaw, thaum organic tin stabilizers ntxiv nyob rau hauv qhov ntau ntawm 1 mus rau 1.5 qhov chaw.
Rau mos PVC thiab PVC muab tshuaj txhuam cov khoom formulations, cov ntsiab lus plasticizer yog siab, thiab cov txheej txheem kub yog tsawg, yog li tus nqi ntawm stabilizer yuav raug txo kom tsim nyog.
(1) Opaque saj zawg zog cov khoom feem ntau siv lead ntsev (1 mus rau 2 qhov chaw) ua ke nrog hlau xab npum (1 mus rau 2 qhov chaw).
(2) Semitransparent saj zawg zog cov khoom feem ntau siv ob peb hlau soaps ua ke, nrog rau ntxiv ntawm 2 mus rau 3 qhov chaw.
(3) Cov khoom lag luam yooj yim pob tshab feem ntau siv cov khoom siv organic (0.5 mus rau 1 feem) ua ke nrog cov xab npum hlau (1 mus rau 2 ntu). Xwb, organic antimony thiab tsis tshua muaj lub ntiaj teb stabilizers tuaj yeem hloov cov organic tin.
Nyob rau hauv non-toxic PVC formulations, xaiv thermal stabilizers:
(1) Cov hmoov txhuas ntsev stabilizer yuav tsum zam.
(2) Hlau xab npum stabilizers uas tsis yog Pb thiab Cd, xws li calcium-zinc stabilizers, tuaj yeem xaiv.
(3) Tsis muaj tshuaj lom cov organic tin stabilizers tuaj yeem xaiv.
(4) Organic antimony thiab tsawg lub ntiaj teb stabilizers tuaj yeem xaiv.
(5) Tsis muaj tshuaj lom epoxy stabilizers hauv auxiliary stabilizers tuaj yeem xaiv.
Kev sib koom ua ke ntawm thawj cov stabilizers: Hauv kev tsim PVC, ntau lub hauv paus stabilizers feem ntau siv ua ke vim tias cov thawj stabilizers sib txawv muaj cov txiaj ntsig zoo.
(1) Tribasic lead sulfate thiab dibasic lead phosphite muaj cov nyhuv synergistic, nrog rau kev sib piv ntawm 2: 1 lossis 1: 1.
(2) Cov xab npum hlau sib txawv muaj cov txiaj ntsig zoo sib xws, nrog rau kev txiav txim siab thermal stability ntawm cov xab npum hlau raws li hauv qab no: Cd, Zn> Pb> Ba, Ca.
(3) Muaj kev sib koom ua ke ntawm cov xab npum hlau thiab cov organic tin stabilizers, thiab ob qho tib si feem ntau siv ua ke hauv cov qauv pob tshab.
(4) Qee qhov tsis tshua muaj lub ntiaj teb stabilizers muaj cov nyhuv synergistic nrog cov organic tin, txo cov nqi thaum hloov cov organic tin.
Synergy ntawm thawj thiab pab stabilizers:
(1) Hlau soaps thiab epoxy
(2) Hlau soaps thiab polyols
(3) Hlau soaps thiab -diketones
(4) Qee lub ntiaj teb tsis tshua muaj thiab epoxy
(5) Hlau soaps thiab organic phosphates
Thaum siv cov thermal stabilizers ua ke nrog lwm cov khoom siv ntxiv, qee cov stabilizers lawv tus kheej tsis muaj cov khoom siv lubricating, xws li cov ntsev ntsev, organic tin, organic antimony, thiab cov av tsis tshua muaj, yog li cov roj lubricants yuav tsum tau muab cais rau hauv cov qauv. Qee cov stabilizers lawv tus kheej muaj cov khoom siv lubricating, xws li cov xab npum hlau, yog li cov roj lubricants tuaj yeem raug tshem tawm lossis txo qis hauv cov qauv.
Sulfur-muaj organic tin stabilizers thiab organic antimony stabilizers yuav tsum tsis txhob siv ua ke nrog Pb- thiab Cd-muaj stabilizers, vim lawv yuav ua rau cov kab mob sulfur thaum siv ua ke.
Antioxidants
Antioxidants nyob rau hauv PVC cov khoom raug oxidation thaum lub sij hawm ua thiab siv vim tshav kub thiab ultraviolet lub teeb, uas muaj feem xyuam rau zus tau tej cov dawb radicals.
Lub luag haujlwm tseem ceeb ntawm cov tshuaj antioxidants tseem ceeb yog kev tshem tawm cov saw hlau los yog cov dawb radical scavenging. Lawv lub luag haujlwm tseem ceeb yog ua ke nrog cov dawb radicals los tsim cov tebchaw ruaj khov, tshem tawm cov tshuaj tiv thaiv kab mob.
Lub ntsiab antioxidant siv rau PVC yog bisphenol A. Kuj tseem muaj auxiliary antioxidants los yog hydrogen peroxide decomposers, xws li triphenyl phosphate thiab benzoylphenyl isooctyl phosphate. Kev sib xyaw ua ke ntawm kev siv thawj zaug thiab cov tshuaj tiv thaiv kab mob antioxidant tuaj yeem ua rau muaj kev sib koom ua ke.
Ultraviolet Absorbers
PVC khoom siv sab nraum zoov yog rhiab heev rau ultraviolet hluav taws xob nyob rau hauv lub rhiab heev wavelength ntau yam, ua rau PVC molecules los ua kev zoo siab los yog tshuaj bonds yuav tsum tau tawg, ua rau lub tsim ntawm dawb radical saw tshua thiab txhawb PVC degradation thiab kev laus. Txhawm rau txhim kho UV tiv thaiv, UV absorbers feem ntau ntxiv.
Feem ntau siv UV absorbers rau PVC muaj xws li triazine-5, UV-9, UV-326, TBS, BAD, thiab OBS. Triazine-5 muaj txiaj ntsig zoo tshaj plaws, tab sis nws muab cov xim daj me ntsis rau zaj duab xis. Ntxiv me me ntawm phthalocyanine xiav tuaj yeem txhim kho qhov no.
Hauv PVC zaj duab xis ua liaj ua teb, UV{{0}} feem ntau yog siv, nrog rau kev siv ntawm 0.2 mus rau 0.5 qhov chaw. TBS, BAD, thiab OBS, uas yog salicylic acid derivatives, muaj cov teebmeem me me thiab, thaum siv ua ke nrog cov tshuaj antioxidants, muab kev laus zoo.
Rau cov khoom lag luam opaque, huab cua tiv thaiv feem ntau tuaj yeem txhim kho los ntawm kev ntxiv daim npog ntsej muag titanium dioxide. Txawm li cas los xij, yog tias UV absorbers tau ntxiv rau lub sijhawm no, yuav tsum muaj ntau npaum li cas, uas yuav tsis raug nqi.