Cov ntsiab lus
1. Wetting thiab dispersing tus neeg sawv cev
2. Defoamer
3. Thickener
4. Film-forming additives
5. Lwm yam additives
Wetting thiab dispersing tus neeg sawv cev
Cov txheej txheem dej siv dej ua cov kuab tshuaj los yog qhov nruab nrab dispersion, thiab cov dej muaj cov dielectric loj tas li, yog li cov txheej txheem dej feem ntau yog ruaj khov los ntawm electrostatic repulsion thaum hluav taws xob ob txheej txheej.
Tsis tas li ntawd, nyob rau hauv cov txheej txheem dej-raws li txheej txheem, feem ntau muaj cov polymers thiab tsis-ionic surfactants, uas yog adsorbed rau saum npoo ntawm cov xim pleev xim, tsim steric hindrance thiab stabilizing cov dispersion. Yog li ntawd, dej-raws li xim thiab emulsions ua tiav cov txiaj ntsig ruaj khov los ntawm kev sib koom ua ke ntawm electrostatic repulsion thiab steric hindrance. Nws qhov tsis zoo yog qhov tsis zoo electrolyte tsis kam, tshwj xeeb tshaj yog rau cov nqi hluav taws xob siab.
1.1 Wetting agent
Cov tshuaj ntub dej rau cov txheej txheem dej tau muab faib ua anionic thiab nonionic.
Kev sib xyaw ua ke ntawm tus neeg sawv cev ntub dej thiab tus neeg sawv cev dispersing tuaj yeem ua tiav cov txiaj ntsig zoo. Tus nqi ntawm tus neeg sawv cev ntub dej feem ntau yog ob peb ntawm ib txhiab. Nws cov nyhuv tsis zoo yog foaming thiab txo cov dej tsis kam ntawm txheej zaj duab xis.
Ib qho ntawm txoj kev loj hlob ntawm cov neeg ua dej ntub dej yog maj mam hloov cov polyoxyethylene alkyl (benzene) phenol ether (APEO lossis APE) cov tshuaj ntub dej, vim tias nws ua rau txo qis ntawm cov txiv neej cov tshuaj hormones hauv nas thiab cuam tshuam nrog endocrine. Polyoxyethylene alkyl (benzene) phenol ethers yog dav siv los ua emulsifiers thaum lub sij hawm emulsion polymerization.
Twin surfactants kuj yog kev tsim kho tshiab. Nws yog ob lub amphiphilic molecules txuas los ntawm lub spacer. Qhov tseem ceeb tshaj plaws ntawm ntxaib-cell surfactants yog qhov tseem ceeb micelle concentration (CMC) ntau dua li qhov kev txiav txim siab qis dua li ntawm lawv cov "single-cell" surfactants, ua raws li kev ua haujlwm siab. Xws li TEGO Twin 4000, nws yog ib tug ntxaib cell siloxane surfactant, thiab muaj tsis ruaj khov ua npuas ncauj thiab defoaming zog.
1.2 Dispersant
Dispersants rau latex xim yog muab faib ua plaub pawg: phosphate dispersants, polyacid homopolymer dispersants, polyacid copolymer dispersants thiab lwm yam dispersants.
Feem ntau siv phosphate dispersants yog polyphosphates, xws li sodium hexametaphosphate, sodium polyphosphate (Calgon N, khoom ntawm BK Giulini Chemical Company nyob rau hauv lub teb chaws Yelemees), poov tshuaj tripolyphosphate (KTPP) thiab tetrapotassium pyrophosphate (TKPP).
Lub mechanism ntawm nws qhov kev txiav txim yog kom stabilize electrostatic repulsion los ntawm hydrogen bonding thiab tshuaj adsorption. Nws qhov zoo dua yog tias qhov ntau npaum li cas yog tsawg, txog 0.1%, thiab nws muaj qhov cuam tshuam zoo rau cov xim tsis muaj zog thiab cov khoom ntim. Tab sis kuj tseem muaj qhov tsis zoo: ib qho, nrog rau kev nce ntawm pH tus nqi thiab qhov kub thiab txias, polyphosphate yog yooj yim hydrolyzed, ua rau lub sij hawm ntev cia stability tsis zoo; Tsis tiav dissolution nyob rau hauv nruab nrab yuav cuam tshuam lub gloss ntawm glossy latex xim.
1 Phosphate dispersant
Phosphate ester dispersants stabilize pigment dispersions, nrog rau cov xim reactive xws li zinc oxide. Hauv gloss xim formulations, nws txhim kho gloss thiab cleanability. Tsis zoo li lwm cov khoom ntub dej thiab dispersing additives, qhov sib ntxiv ntawm phosphate ester dispersants tsis cuam tshuam rau KU thiab ICI viscosity ntawm txheej.
Polyacid homopolymer dispersant, xws li Tamol 1254 thiab Tamol 850, Tamol 850 yog homopolymer ntawm methacrylic acid.
Polyacid copolymer dispersant, xws li Orotan 731A, uas yog ib tug copolymer ntawm diisobutylene thiab maleic acid. Cov yam ntxwv ntawm ob hom dispersants no yog tias lawv tsim muaj zog adsorption los yog anchoring rau saum npoo ntawm pigments thiab fillers, muaj ntev molecular chains los tsim steric hindrance, thiab muaj dej solubility ntawm cov saw xaus, thiab ib co yog supplemented los ntawm electrostatic repulsion. ua tiav cov txiaj ntsig ruaj khov. Yuav kom cov dispersant muaj zoo dispersibility, qhov hnyav molecular yuav tsum nruj me ntsis tswj. Yog tias qhov hnyav molecular me dhau, yuav muaj qhov tsis txaus steric hindrance; Yog tias qhov hnyav molecular loj dhau, flocculation yuav tshwm sim. Rau polyacrylate dispersants, qhov zoo tshaj plaws dispersion nyhuv tuaj yeem ua tiav yog tias qib ntawm polymerization yog 12-18.
Lwm hom dispersants, xws li AMP-95, muaj tshuaj npe 2-amino-2-methyl-1-propanol. Cov amino pawg yog adsorbed rau ntawm qhov chaw ntawm cov khoom tsis muaj zog, thiab pawg hydroxyl txuas mus rau dej, uas ua lub luag haujlwm ruaj khov los ntawm kev cuam tshuam tsis zoo. Vim nws qhov me me, steric hindrance yog txwv. AMP-95 feem ntau yog pH regulator.
Nyob rau hauv xyoo tas los no, kev tshawb fawb ntawm dispersants tau kov yeej qhov teeb meem ntawm flocculation los ntawm siab molecular hnyav, thiab kev loj hlob ntawm siab molecular hnyav yog ib qho ntawm cov qauv. Piv txwv li, lub siab molecular hnyav dispersant EFKA-4580 ua los ntawm emulsion polymerization tshwj xeeb yog tsim los rau cov dej-raws li kev lag luam txheej, haum rau cov organic thiab inorganic pigment dispersion, thiab muaj dej tsis kam.
Amino pawg muaj kev sib raug zoo rau ntau cov xim los ntawm acid-base lossis hydrogen bonding. Cov block copolymer dispersant nrog aminoacrylic acid raws li cov pab pawg neeg anchoring tau raug them rau.
2 Dispersant nrog dimethylaminoethyl methacrylate raws li pab pawg neeg anchoring
Tego Dispers 655 wetting thiab dispersing additive yog siv nyob rau hauv waterborne automotive xim tsis tsuas yog rau taw qhia cov pigments tab sis kuj los tiv thaiv cov hmoov txhuas los ntawm reacting nrog dej.
Vim muaj kev txhawj xeeb ntawm ib puag ncig, biodegradable wetting thiab dispersing agents tau tsim, xws li EnviroGem AE series twin-cell wetting thiab dispersing agents, uas yog low-foaming wetting thiab dispersing agents.
Defoamer
Muaj ntau ntau hom tshuaj pleev xim rau dej, uas feem ntau muab faib ua peb pawg: ntxhia roj defoamers, polysiloxane defoamers thiab lwm yam defoamers.
Mineral roj defoamers feem ntau yog siv, feem ntau hauv cov xim tiaj tus thiab semi-gloss latex.
Polysiloxane Defoamers muaj cov npoo tsis muaj zog, muaj zog defoaming thiab antifoaming muaj peev xwm, lawv yuav tsis cuam tshuam rau qhov tsis xws luag xws li shrinkage ntawm txheej zaj duab xis thiab kev ua yeeb yam tsis zoo.
Ib txwm siv dej-raws li cov xim defoamers tsis sib haum nrog cov theem dej kom ua tiav lub hom phiaj ntawm defoaming, yog li nws yooj yim los tsim qhov tsis xws luag hauv zaj duab xis txheej.
Nyob rau hauv xyoo tas los no, molecular-theem defoamers tau tsim.
Tus neeg sawv cev antifoaming no yog ib qho polymer tsim los ntawm ncaj qha grafting antifoaming active tshuaj ntawm cov cab kuj. Cov saw hlau molecular ntawm cov polymer muaj ib pawg ntub dej hydroxyl, defoaming active tshuaj yog faib nyob ib ncig ntawm lub molecule, cov active tshuaj tsis yooj yim rau aggregate, thiab compatibility nrog txheej txheej yog zoo. Xws li molecular-theem defoamers suav nrog cov roj ntxhia - FoamStar A10 series, silicon-muaj - FoamStar A30 series, thiab non-silicon, non-roj polymers - FoamStar MF series.
Qhov no molecular-scale defoamer siv lub hnub qub supergrafted polymer ua ib qho tsis sib xws surfactant thiab tau ua tiav cov txiaj ntsig zoo hauv cov ntawv thov txheej dej. Cov Khoom Cua Molecular-qib defoamer qhia los ntawm Stout et al. yog acetylene glycol-raws li ua npuas ncauj tswj tus neeg saib xyuas thiab defoamer nrog ob qho tib si ntub dej, xws li Surfynol MD 20 thiab Surfynol DF 37.
Tsis tas li ntawd, txhawm rau ua kom tau raws li qhov xav tau ntawm kev tsim cov xoom-VOC txheej, kuj tseem muaj VOC-dawb defoamers, xws li Agitan 315, Agitan E 255, thiab lwm yam.
tuab
Muaj ntau ntau hom thickeners, tam sim no feem ntau siv yog cellulose ether thiab nws cov derivatives thickeners, associative alkali-swellable thickeners (HASE) thiab polyurethane thickeners (HEUR).
3.1. Cellulose ether thiab nws cov derivatives
Hydroxyethyl cellulose (HEC)yog thawj zaug ua lag luam los ntawm Union Carbide Company nyob rau hauv 1932, thiab muaj keeb kwm ntawm ntau tshaj 70 xyoo.
Tam sim no, cov thickeners ntawm cellulose ether thiab nws cov derivatives feem ntau suav nrog hydroxyethyl cellulose (HEC), methyl hydroxyethyl cellulose (MHEC), ethyl hydroxyethyl cellulose (EHEC), methyl hydroxypropyl Base cellulose (MHPC), methyl cellulose (MC) thiab xanthan gum, thiab lwm yam., cov no yog non-ionic thickeners, thiab kuj yog cov uas tsis yog-sociated dej theem thickeners. Ntawm lawv, HEC yog feem ntau siv hauv cov xim latex.
3.2 Alkali-swellable thickener
Alkali-swellable thickeners muab faib ua ob pawg: non-associative alkali-swellable thickeners (ASE) thiab associative alkali-swellable thickeners (HASE), uas yog anionic thickeners. Tsis yog koom nrog ASE yog polyacrylate alkali o emulsion.
3.3. Polyurethane thickener thiab hydrophobically hloov tsis-polyurethane thickener
Polyurethane thickener, hu ua HEUR, yog ib pawg hydrophobic hloov kho ethoxylated polyurethane dej-soluble polymer, uas belongs rau non-ionic associative thickener.
HEUR yog tsim los ntawm peb ntu: pawg hydrophobic, hydrophilic saw thiab polyurethane pawg.
Cov pab pawg neeg hydrophobic plays lub luag haujlwm ntawm lub koom haum thiab yog qhov txiav txim siab ua kom tuab, feem ntau yog oleyl, octadecyl, dodecylphenyl, nonylphenol, thiab lwm yam.
Txawm li cas los xij, qhov kev hloov pauv ntawm pawg hydrophobic ntawm ob qho kawg ntawm qee qhov kev lag luam muaj HEURs qis dua 0.9, thiab qhov zoo tshaj plaws tsuas yog 1.7. Cov tshuaj tiv thaiv yuav tsum tau tswj nruj me ntsis kom tau txais polyurethane thickener nrog nqaim molecular hnyav faib thiab kev ua haujlwm ruaj khov. Feem ntau HEURs yog synthesized los ntawm stepwise polymerization, yog li kev lag luam muaj HEURs feem ntau sib xyaw ntawm qhov hnyav molecular.
Ntxiv rau qhov linear associative polyurethane thickeners tau piav saum toj no, kuj tseem muaj cov comb-zoo li associative polyurethane thickeners. Lub npe hu ua comb Association polyurethane thickener txhais tau hais tias muaj ib pawg pendant hydrophobic nyob rau hauv nruab nrab ntawm txhua thickener molecule. Cov thickeners xws li SCT-200 thiab SCT-275 thiab lwm yam.
Thaum ntxiv cov nyiaj ib txwm muaj ntawm pawg hydrophobic, tsuas muaj 2 pawg hydrophobic kawg nkaus xwb, yog li cov synthesized hydrophobically hloov cov amino thickener tsis txawv ntawm HEUR, xws li Optiflo H 500, saib daim duab 3.
Yog tias muaj ntau pawg hydrophobic ntxiv, xws li txog li 8%, cov tshuaj tiv thaiv tuaj yeem hloov kho kom tsim cov amino thickeners nrog ntau pawg hydrophobic blocked. Ntawm chav kawm, qhov no kuj yog ib tug comb thickener.
Qhov no hydrophobic hloov kho amino thickener tuaj yeem tiv thaiv cov xim viscosity los ntawm kev poob vim qhov sib ntxiv ntawm cov nyiaj ntau ntawm surfactants thiab glycol cov kuab tshuaj thaum xim sib ntxiv. Yog vim li cas yog tias pawg hydrophobic muaj zog tuaj yeem tiv thaiv desorption, thiab ntau pawg hydrophobic muaj kev sib koom ua ke.
Post lub sij hawm: Dec-26-2022