Hauv ntau qhov chaw xws li kev tsim tshuaj lom neeg, kev kho dej, kev ua zaub mov, thiab txheej txheej thiab inks, ua npuas ncauj feem ntau cuam tshuam rau kev tsim khoom, khoom zoo, thiab kev nyab xeeb ntawm cov txheej txheem. Defoamers, raws li cov ntsiab lus ntxiv rau kev daws teeb meem ua npuas ncauj, tau ntev ua ib feem tseem ceeb ntawm kev tsim khoom lag luam. Tam sim no, defoamers ntawm kev ua lag luam feem ntau muab faib ua ob lub chaw pw hav zoov -silicone defoamers thiab silicone- dawb defoamers. Vim qhov sib txawv ntawm qhov sib xyaw thiab cov qauv, lawv sib txawv hauv kev ua tau zoo, cov xwm txheej siv tau, thiab kev txwv kev siv. Kev xaiv tsis raug tsis tsuas yog daws tsis tau qhov teeb meem ua npuas ncauj xwb tab sis kuj tseem tuaj yeem ua rau cov khoom tsis xws luag, txheej txheem tsis ua haujlwm, thiab lwm yam kev phom sij zais.
Lub luag haujlwm tseem ceeb ntawm defoamers yog cuam tshuam kev ruaj ntseg ntawm npuas. Los ntawm kev txo qhov nro ntawm cov npuas dej thiab cuam tshuam cov qauv ua npuas ncauj, lawv ua tiav ob qho kev cuam tshuam ntawm kev tawg thiab ua npuas ncauj. Qhov sib txawv tseem ceeb ntawm silicone thiab silicone -dawb defoamers nyob hauv lawv cov khoom xyaw tseem ceeb sib txawv, uas tseem txiav txim siab qhov sib txawv ntawm lawv cov kev ua tau zoo thiab kev siv tom qab.
Cov khoom xyaw tseem ceeb ntawm silicone defoamers yog polysiloxane (tseem hu ua silicone roj), uas feem ntau yog sib xyaw nrog cov khoom siv hydrophobic (xws li hydrophobic silica kho nrog silicone roj), emulsifiers, nqa thiab lwm yam khoom siv los ua kom tiav.
Nws cov qauv tseem ceeb muaj kev sib hloov helical molecular chains ntawm siloxanes (Si-O), nrog rau txhua lub silicon atom feem ntau sib txuas rau ob pawg methyl. Cov qauv tshwj xeeb no ua rau nws tsis tshua muaj qhov nro (feem ntau 20-21 dynes/cm, qis dua dej 72 dynes/cm) thiab tshuaj lom neeg ruaj khov, tiv thaiv nws los ntawm cov kua qaub feem ntau -base- ntsev tshuab. Cov hom silicone defoamers muaj xws li polydimethylsiloxane defoamers thiab polyether- hloov silicone defoamers. Polyether-hloov cov khoom, los ntawm kev qhia polyether ntu rau hauv siloxane molecule, muab cov kev ua haujlwm siab defoaming ntawm silicone nrog kev sib raug zoo ntawm polyether, ua rau lawv tsim nyog rau ntau lub tshuab. Cov khoom hloov kho no kuj muaj lub lubrication, kis tau, thiab emulsification stability muab los ntawm polyether ntu, ntxiv nthuav lawv daim ntawv thov scenarios.
Silicone-dawb defoamers (tseem hu ua non-silicone defoamers) xa mus rau defoamers uas tsis muaj siloxane Cheebtsam. Lawv cov khoom xyaw tseem ceeb feem ntau suav nrog cov khoom tsis yog-silicone xws li polyethers, ntxhia roj, fatty alcohols, fatty acid esters, thiab acrylic polymers. Zoo ib yam li silicone defoamers, silicone-dawb defoamers kuj ua tiav lawv cov nyhuv defoaming los ntawm kev txo qhov nro ntawm cov npuas dej thiab cuam tshuam cov qauv ua npuas ncauj. Qhov txawv yog qhov tseeb tias lawv cov khoom xyaw nquag feem ntau yog dej-soluble lossis roj-soluble organic tshuaj, tso siab rau lawv tus kheej nto-cov khoom muaj zog los ua kom lawv cov teebmeem.
Ntawm lawv, polyether defoamers (xws li polyoxypropylene-polyoxyethylene block copolymer) yog cov khoom siv silicone feem ntau -dawb defoamers, nrog zoo sib xws thiab rov qab solubility (huab point effect). Lawv precipitate thiab defoam ntawm qhov kub thiab txias thiab yaj hauv dej ntawm qhov kub thiab txias. Mineral roj defoamers siv cov roj ntxhia ua cov khoom thauj thiab sib xyaw nrog cov khoom siv hydrophobic, uas muaj tus nqi qis dua. Fatty cawv thiab ester defoamers muaj biodegradability zoo thiab tsim nyog rau cov xwm txheej uas muaj kev tiv thaiv ib puag ncig siab.
Daim ntawv thov scenarios
Silicone defoamers, nrog rau lawv qhov zoo ntawm kev defoaming sai, ntev - ua npuas ncauj tiv thaiv, tsis kam mus rau qhov kub thiab txias, thiab tsis kam mus rau acids thiab alkalis, yog dav siv nyob rau hauv teb nrog siab defoaming efficiency yuav tsum thiab hnyav txheej txheem ib puag ncig. Lawv yog tshwj xeeb tshaj yog haum rau scenarios nrog loj npaum li cas ntawm npuas thiab nruam ua npuas ncauj tiam. Cov ntawv thov tshwj xeeb yog raws li hauv qab no:
Hauv kev tsim tshuaj lom neeg, silicone defoamers yog tsim rau ntau yam tshuaj tiv thaiv, tshuaj nplawm, distillation, rho tawm, thiab lwm yam txheej txheem, xws li kev tsim cov khoom siv hluavtaws, roj hmab, txheej raw cov ntaub ntawv, thiab cov kua qaub- puag nruab nrab cov tshuaj tiv thaiv. Vim tias kev tsim tshuaj lom neeg feem ntau cuam tshuam nrog cov xwm txheej hnyav xws li kub siab, kub siab, thiab muaj zog acids thiab alkalis, tshuaj lom neeg ruaj khov thiab kub tsis kam ntawm silicone defoamers ua tau raws li cov kev cai no, tiv thaiv cov teeb meem zoo xws li txo qis cov tshuaj tiv thaiv thiab cov khoom pov tseg los ntawm ua npuas ncauj. Piv txwv li, nyob rau hauv cov tshuaj tiv thaiv polyurethane synthesis, silicone defoamers tuaj yeem tshem tawm qhov ntau ntawm cov npuas dej thaum lub sij hawm cov tshuaj tiv thaiv, kom ntseeg tau tias cov khoom hnyav molecular ntawm cov khoom; nyob rau hauv txheej txheej raw khoom, lawv muaj peev xwm suppress ua npuas ncauj thaum lub sij hawm pigment dispersion, txhim kho raw khoom purity.
Silicone-dawb defoamers, nrog rau lawv qhov zoo ntawm kev sib raug zoo, tsis muaj silicone residue, thiab yooj yim biodegradability, feem ntau yog siv nyob rau hauv cov xwm txheej uas cov khoom purity thiab deg zoo yuav tsum siab, los yog qhov twg silicone Cheebtsam raug txwv. Cov ntawv thov tshwj xeeb yog raws li hauv qab no:
Hauv kev lag luam coatings, inks, thiab adhesives, qhov no yog ib qho ntawm cov khoom siv tseem ceeb rau cov khoom siv silicone -dawb defoamers, tshwj xeeb tshaj yog tsim rau qib siab - qib ntoo coatings, automotive paints, metallic paints, UV curing systems, plastic coatings (PP, ABS, etc.), thiab polyolefin film printing inks. Hauv cov ntawv thov no, silicone defoamers tuaj yeem yooj yim ua rau qhov tsis xws luag xws li pinholes, fisheyes, thiab silicone me ntsis, cuam tshuam rau txheej txheej, adhesion, thiab luam ntawv tau. Silicone-dawb defoamers (xws li acrylic polymers thiab polyethers) muaj kev sib raug zoo, zoo defoaming yam tsis muaj kev cuam tshuam cov khoom muag lossis kev ua haujlwm tom qab (xws li recoatability thiab daim ntawv cog lus zog). Piv txwv li, nyob rau hauv LED encapsulation adhesives thiab optical tivthaiv potting, silicone -dawb defoamers xyuas kom meej tias cov potted qhov chaw yog pob tshab, pinhole -dawb, thiab tsis muaj kev cuam tshuam rau optical kev ua tau zoo los yog adhesion.
Hauv cov khoom siv hluav taws xob thiab kev ua haujlwm siab, cov khoom no tsim nyog rau kev tu PCB, kev siv hluav taws xob hauv hluav taws xob, thiab kev ua cov hlau precision (steel phaj tu, phosphating, pre{0}}plating kev kho mob), thiab lwm yam xwm txheej. Silicone Cheebtsam yog nruj me ntsis tswj cov kab mob hauv kev lag luam semiconductor. Silicon residual tuaj yeem ua rau luv luv Circuit Court, tsis zoo soldering, thiab deterioration ntawm phosphating zaj duab xis zoo. Silicone-dawb defoamers (xws li cov polyethers tshwj xeeb thiab fluorocarbons) tawm tsis muaj silicone seem, tsis txhob muaj cov pa phem silicon thiab ua kom cov khoom raug thiab ua haujlwm zoo. Piv txwv li, hauv PCB tu, silicone-dawb defoamers tshem tawm cov npuas dej hauv cov tshuaj ntxuav tsis tau tawm ntawm impurities, ua kom cov rwb thaiv tsev ua haujlwm ntawm lub rooj tsav xwm Circuit Court.
Hauv kev lag luam textile thiab dyeing kev lag luam, nws tsim nyog rau dyeing, luam ntawv, thiab ua tiav (softening) ntawm lub teeb - xim ntaub. Silicone residue yog qhov nyuaj rau ntxuav tawm thiab tuaj yeem tsim "silicon me ntsis" tom qab ziab, ua rau muaj xim txawv thiab xim sib txawv. Nws kuj tseem tuaj yeem cuam tshuam nrog silicone softeners. Fatty alcohol emulsions thiab polyether-raws li silicone-dawb defoamers tuaj yeem zam cov teeb meem no, ua kom cov xim tsis sib xws thiab cov ntaub huv huv.
Silicone defoamers thiab silicone-dawb defoamers tsis yog "tawm tsam hauv qhov zoo," tab sis txhua tus muaj nws tus kheej lub zog thiab tsim nyog rau cov xwm txheej sib txawv: silicone defoamers yog qhov zoo tshaj plaws ntawm kev ua haujlwm siab, ntev - cov nyhuv kav ntev, thiab tsis kam rau qhov hnyav ib puag ncig, ua rau lawv tsim nyog rau cov xwm txheej uas xav tau siab rau defoaming efficiency ntawm silicone thiab tsis muaj reidue. silicone-dawb defoamers yog superior nyob rau hauv cov nqe lus ntawm zoo compatibility, tsis muaj residue, thiab ib puag ncig tus phooj ywg, ua rau lawv haum rau scenarios uas yuav tsum tau siab rau cov khoom zoo thiab kev tiv thaiv ib puag ncig, thiab qhov twg silicone Cheebtsam raug txwv.
