I. Txheej txheem cej luam
Raws li ib qho ntawm cov khoom siv raw ntawm cov txheej txheej, tus nqi ntawm cov tshuaj ntxiv yog feem ntau me me (feem ntau txog 1% ntawm tag nrho cov qauv), tab sis cov nyhuv zoo heev.Qhov sib ntxiv ntawm nws tuaj yeem tsis tsuas yog zam ntau txheej txheej tsis xws luag thiab zaj duab xis tsis xws luag, tab sis kuj ua rau cov txheej txheem ntau lawm thiab kev tsim kho ntawm cov txheej txheem yooj yim los tswj, thiab qhov sib ntxiv ntawm qee yam additives tuaj yeem ua rau cov txheej txheem nrog qee qhov tshwj xeeb.Yog li ntawd, additives yog ib feem tseem ceeb ntawm txheej txheej.
2. Kev faib tawm ntawm cov khoom ntxiv
Feem ntau siv additives rau coatings muaj xws li organic anti-settling agents, thickeners, leveling agents, foam control agents, adhesion promoters, wetting and dispersing agents, etc.
3. Kev ua tau zoo thiab kev siv cov tshuaj ntxiv
(1) Organic tshuaj tiv thaiv kab mob
Feem ntau ntawm cov khoom no yog raws li polyolefins, dispersed nyob rau hauv ib co hnyav, tej zaum hloov nrog ib tug castor roj derivative.Cov additives no tuaj nyob rau hauv peb hom: kua, muab tshuaj txhuam, thiab hmoov.
1. Rheological zog:
Lub ntsiab rheological muaj nuj nqi ntawm cov organic tshuaj tiv thaiv kev daws teeb meem yog los tswj lub ncua kev kawm ntawm pigments - uas yog, tiv thaiv nyuaj los yog kom tsis txhob nyob rau hauv tag nrho, uas yog lawv daim ntawv thov raug.Tab sis nyob rau hauv kev xyaum, nws ua rau ib tug nce nyob rau hauv viscosity thiab kuj muaj ib co degree ntawm sag kuj, tshwj xeeb tshaj yog nyob rau hauv industrial coatings.Organic los tiv thaiv kev daws teeb meem yuav yaj vim qhov kub siab, yog li poob lawv cov txiaj ntsig, tab sis lawv cov rheology yuav rov zoo li lub cev txias.
2. Daim ntawv thov ntawm cov organic tshuaj tiv thaiv kab mob:
Txhawm rau ua kom tus neeg sawv cev tiv thaiv ua haujlwm tau zoo hauv cov txheej txheem, nws yuav tsum tau muab faib ua kom zoo thiab ua haujlwm.Cov kauj ruam tshwj xeeb yog raws li hauv qab no:
(1) Kev ntub dej (cov hmoov qhuav xwb).Cov hmoov qhuav organic anti-sedimentation tus neeg sawv cev yog ib qho sib xyaw ua ke, txhawm rau txhawm rau cais cov khoom ntawm ib leeg, nws yuav tsum tau wetted los ntawm hnyav thiab (los yog) resin.Nws yog feem ntau txaus los ntxiv nws mus rau kev sib tsoo slurry nrog nruab nrab agitation.
(2) Deagglomeration (tsuas yog rau cov hmoov qhuav).Lub zog sib sau ua ke ntawm cov organic anti-sedimentation agents tsis muaj zog heev, thiab kev sib xyaw yooj yim sib xyaw yog txaus nyob rau hauv feem ntau.
(3) Dispersion, cua sov, lub sij hawm ntawm dispersion (txhua yam).Tag nrho cov organic anti-sedimentation agents muaj qhov tsawg kawg nkaus ua kom kub, thiab yog hais tias nws tsis mus txog, txawm lub dispersing quab yuam loj npaum li cas, yuav tsis muaj kev ua rheological.Qhov ua kom kub yog nyob ntawm cov kuab tshuaj siv.Thaum qhov ntsuas kub tsawg kawg nkaus, qhov kev ntxhov siab thov yuav qhib cov organic anti-sedimentation tus neeg sawv cev thiab muab kev ua si tag nrho rau nws qhov kev ua tau zoo.
(2) Thickener
Muaj ntau hom thickeners siv nyob rau hauv hnyav-raws li thiab dej-raws li xim.Feem ntau hom thickeners siv nyob rau hauv waterborne coatings yog: cellulose ethers, polyacrylates, associative thickeners thiab inorganic thickeners.
1. Feem ntau siv cellulose ether thickener yog hydroxyethyl cellulose (HEC).Nyob ntawm qhov viscosity, muaj ntau qhov sib txawv.HEC yog cov khoom siv hmoov dej-soluble, uas yog non-ionic thickener.Nws muaj cov nyhuv thickening zoo, dej tsis kam thiab alkali tsis kam, tab sis nws qhov tsis zoo yog tias nws yooj yim loj hlob pwm, rot, thiab muaj cov khoom tsis zoo.
2. Lub polyacrylate thickener yog ib qho acrylate copolymer emulsion nrog cov ntsiab lus carboxyl siab, thiab nws qhov loj tshaj plaws yog nws qhov zoo tiv thaiv pwm ntxeem tau.Thaum pH yog 8-10, hom thickener no yuav o thiab ua rau cov viscosity ntawm cov dej theem;tab sis thaum pH ntau dua 10, nws yaj hauv dej thiab poob nws cov nyhuv thickening.Yog li ntawd, muaj ntau rhiab heev rau pH.Tam sim no, ammonia dej yog qhov feem ntau siv pH adjuster rau latex xim hauv Suav teb.Yog li ntawd, thaum siv hom thickener no, tus nqi pH yuav txo nrog cov volatilization ntawm ammonia dej, thiab nws cov thickening nyhuv kuj yuav txo.
3. Associative thickeners muaj cov txheej txheem sib txawv los ntawm lwm hom thickeners.Feem ntau cov thickeners coj viscosity los ntawm hydration thiab tsim ib tug tsis muaj zog gel qauv nyob rau hauv lub system.Txawm li cas los xij, associative thickeners, zoo li surfactants, muaj ob qho tib si hydrophilic qhov chaw thiab lub qhov ncauj-phooj ywg daj ntxuav cov roj hauv cov molecule.Cov khoom siv hydrophilic tuaj yeem hydrated thiab swelled kom thicken cov dej theem.Cov pab pawg lipophilic kawg tuaj yeem ua ke nrog cov khoom emulsion thiab cov xim xim.koom tes los tsim ib lub network qauv.
4. Lub inorganic thickener yog sawv cev los ntawm bentonite.Feem ntau cov dej-based bentonite swells thaum nws nqus dej, thiab qhov ntim tom qab nqus dej yog ob peb zaug nws qhov ntim thawj.Nws tsis tsuas yog ua raws li cov thickener, tab sis kuj tiv thaiv kev poob dej, sagging, thiab ntab xim.Nws cov nyhuv thickening yog zoo dua li ntawm alkali-swellable acrylic thiab polyurethane thickeners nyob rau tib tus nqi.Tsis tas li ntawd, nws kuj muaj ntau yam ntawm pH adaptability, zoo khov-thaw stability thiab lom stability.Vim tias nws tsis muaj cov dej-soluble surfactants, cov khoom zoo hauv cov yeeb yaj kiab qhuav tuaj yeem tiv thaiv cov dej tsiv teb tsaws thiab nthuav dav, thiab tuaj yeem txhim kho cov dej tsis kam ntawm cov zaj duab xis txheej.
(3) leveling agent
Muaj peb yam tseem ceeb ntawm leveling agents feem ntau siv:
1. Hloov kho polysiloxane hom leveling tus neeg sawv cev
Hom txheej txheej no tuaj yeem txo qhov nro ntawm cov txheej txheej, txhim kho lub wettability ntawm txheej rau substrate, thiab tiv thaiv kom txhob shrinkage;nws tuaj yeem txo qhov sib txawv ntawm qhov sib txawv ntawm qhov chaw ntub dej vim qhov hnyav volatilization, txhim kho cov dej ntws hauv lub xeev, thiab ua rau cov xim yog sai sai;hom ntawm tus neeg sawv cev no kuj tuaj yeem tsim cov yeeb yaj kiab tsis tshua muaj neeg nyias thiab du ntawm cov yeeb yaj kiab txheej txheej, yog li txhim kho qhov smoothness thiab gloss ntawm txheej txheej zaj duab xis nto.
2. Long-chain resin hom leveling tus neeg saib xyuas nrog txwv tsis pub muaj kev sib raug zoo
Xws li acrylate homopolymer lossis copolymer, uas tuaj yeem txo qhov nro ntawm cov txheej txheej thiab cov substrate rau qee yam los txhim kho wettability thiab tiv thaiv kom tsis txhob shrinkage;thiab tuaj yeem tsim ib theem molecular rau ntawm qhov chaw ntawm txheej zaj duab xis kom nce qhov nro ntawm cov txheej txheej Homogenize, txhim kho qhov dej ntws tawm, inhibit hnyav volatilization ceev, tshem tawm cov teeb meem xws li txiv kab ntxwv tev thiab txhuam cov cim, thiab ua rau cov txheej txheem txheej txheem du thiab txawm.
3. Leveling tus neeg sawv cev nrog siab boiling point hnyav raws li lub ntsiab tivthaiv
Hom txheej txheem no tuaj yeem kho tus nqi volatilization ntawm cov kuab tshuaj, kom cov zaj duab xis txheej muaj qhov sib npaug ntawm cov volatilization thiab solvency thaum lub sij hawm ziab, thiab tiv thaiv qhov ntws ntawm txheej zaj duab xis los ntawm kev cuam tshuam los ntawm cov kuab tshuaj volatilization sai heev thiab Lub viscosity siab dhau lawm, ua rau tsis zoo ntawm cov theem tsis zoo, thiab tuaj yeem tiv thaiv qhov shrinkage los ntawm kev tsis zoo ntawm cov khoom siv hauv paus thiab nag lossis daus los ntawm cov kuab tshuaj volatilization sai heev.
(4) Ua npuas ncauj tswj tus neeg saib xyuas
Cov tshuaj tiv thaiv ua npuas ncauj kuj hu ua cov tshuaj tiv thaiv kab mob los yog cov tshuaj defoaming.Anti-foaming agents tiv thaiv los yog ncua kev tsim ua npuas ncauj: Anti-foaming agents yog surfactants uas tawg npuas uas tau tsim.Qhov sib txawv ntawm ob tsuas yog theoretical rau qee qhov, ib qho kev ua tau zoo defoamer tuaj yeem tiv thaiv kev tsim ua npuas ncauj zoo li tus neeg sawv cev antifoam.Feem ntau hais lus, antifoaming tus neeg sawv cev yog tsim los ntawm peb yam tseem ceeb: active compound (ie, active agent);diffusing tus neeg sawv cev (muaj los yog tsis);tus cab kuj.
(5) Wetting thiab dispersing agents
Wetting thiab dispersing agents tuaj yeem muaj ntau yam haujlwm, tab sis ob lub luag haujlwm tseem ceeb yog txo lub sijhawm thiab / lossis lub zog xav tau los ua kom tiav cov txheej txheem dispersion thaum stabilizing cov xim dispersion.Wetting agents thiab dispersants feem ntau muab faib ua cov hauv qab no
Tsib qeb:
1. Anionic wetting agent
2. Cationic wetting agent
3. Electroneutral, amphoteric wetting agent
4. Bifunctional, tsis yog hluav taws xob nruab nrab wetting tus neeg saib xyuas
5. Tsis-ionic wetting agent
Thawj plaub hom wetting agents thiab dispersants tuaj yeem ua lub luag haujlwm wetting thiab pab pigment dispersion vim tias lawv cov hydrophilic kawg muaj peev xwm tsim lub cev thiab tshuaj bonds nrog pigment nto, npoo, ces kaum, thiab lwm yam., thiab txav mus rau lub Orientation ntawm lub pigment nto, feem ntau yog qhov kawg hydrophobic.Nonionic wetting thiab dispersing agents kuj muaj cov pab pawg neeg kawg hydrophilic, tab sis lawv tsis tuaj yeem tsim lub cev thiab tshuaj bonds nrog cov xim nto, tab sis tuaj yeem ua ke nrog cov dej adsorbed ntawm cov xim pigment.Cov dej no khi rau cov xim particle nto tsis ruaj khov thiab ua rau tsis muaj ionic nqus thiab desorption.Lub desorbed surfactant nyob rau hauv no resin system yog dawb thiab nyhav ua rau muaj kev phiv xws li dej tsis zoo.
Tus neeg sawv cev wetting thiab dispersant yuav tsum tau ntxiv thaum lub sij hawm pigment dispersion txheej txheem, thiaj li yuav xyuas kom meej tias lwm yam nto active tshuaj muaj peev xwm nyob rau hauv kev sib cuag nrog cov pigment mus ua si lawv lub luag hauj lwm ua ntej mus txog lub nto ntawm lub pigment particle.
Plaub.Cov ntsiab lus
Txheej yog ib tug complex system.Raws li ib feem ntawm lub kaw lus, cov khoom siv ntxiv tau ntxiv me me, tab sis lawv ua lub luag haujlwm tseem ceeb hauv nws qhov kev ua tau zoo.Yog li ntawd, thaum tsim cov kuab tshuaj raws li txheej, uas additives rau siv thiab lawv npaum li cas yuav tsum tau txiav txim los ntawm ib tug loj tus naj npawb ntawm rov qab thwmsim.
Post lub sij hawm: Jan-30-2023