Silicone defoamers yog ua tau zoo thiab dav siv defoaming khoom hauv ntau yam khoom siv tseem ceeb ntawm cov khoom sib xyaw ua ke ntawm Silicone defoamers thiab lawv cov tshuab kev ua.
Ib . cov tseem ceeb ntawm cov khoom seem ntawm silicone defosamer
1. roj silicone (polysiloxane)
Silicone Roj yog cov khoom siv uas nquag muaj ntawm silicone defoamers, feem ntau yog accounting rau 5% {% ntawm cov mis.}} Mas suav nrog:
Siletyl Silicone Roj (polydimethylsiloxane, Laim: molecular hnyav ntawm {}}, dav viscosity ntau ({1}} cst)
Hloov cov roj Silicone
Silicone roj lwg muaj qhov sib tw -si-o- cov saw hlau thiab ntau dua li ntawm 82mn / m, qis dua ntawm nws lub peev xwm defoaming muaj peev xwm.
2. hydrophobic hais
Tso nyiaj rau txog 5% {-15}% ntawm cov qauv, cov hom tseem ceeb muaj:
Silicon Dioxide (fumed silica): particle loj 10-30 nm, thaj tsam nto150-300 m² / g
Hydrophobic calcium carbonate
Polytetrafluoroethylene (PTFE) hmoov
Hlau xab npum (xws li txhuas stearate, calcium stearate)
These particles are surface treated with silicone oil or organosilane (such as hexamethyldisilazane) and are highly hydrophobic with a contact angle of >90 .
{{03. emulsifier / dispersant
Kev suav nyiaj rau txog 3% {-10% ntawm cov mis, siv los ua kom ruaj khov emulsion defoamers:
Surfactants Tsis-ionic: Nthuav / Tween Series, Polyoxyylenethylene
Anionic Surfactants: sodium dodecylbenzene sulfonate (sdbs)
Tshwj xeeb silicone surfactants: xws li polyether-hloov silicone
{{0 {}} Tus Kws nqa khoom nruab nrab
Cov account rau txog li 50% -80}% ntawm cov qauv:
Dej (emulsion hom)
Cov Roj Ntxhia, Roj Dawb (Roj-Raws Li Roj
Cawv (xws li propylene glycol)
Ester (xws li isopropylal patmitate)
Ob {.} ib qho khoom xyaw
Thickener (0.1% {{-2%): carboxymethyl cellulose (cmc), polyacrylic acid
Tshuaj Tiv Thaiv (0.05% -0.3%): isothiazolinone, sodium benzoate
pX excectionter: citric acid, Triethanolamine
Synergist: Cwj Pwm Fatty Fatty (xws li Octanol), Polyether
Peb {.} Cov lus piav qhia ntxaws ntxaws ntawm cov tshuab ntawm kev ua
{{01. Peb-theem kev xav ntawm cov txheej txheem defoaming
Theem 1: Ua npuas ncauj lees paub thiab txoj kev
Lub Qe Tsawg Tshaj Plaws Ntawm Cov Roj Silicone ua rau nws mus sib kis tau nthawv nyob saum npoo ntawm cov npuas dej zaj duab xis
Hydrophobic hais kom haum rau cov npuas interface los ntawm kev sib tsoo lossis xim av suab
Theem 2: Ua Kua Zaj Duab Zaj Duab Xis
Silicone roj-particle complex ua ib "choj" qauv ntawm cov kua zaj duab xis
Raws li cov nyhuv marangoni, cov dav dav dav rau cov kua dej hauv zos
Hais ua "lub kaum sab xis kaum sab xis asymmetry" nyhuv, rhuav cov tshuab sib npaug ntawm cov kua txiv ua kua
Theem 3: Ua npuas ncauj tawg
Tsim cov ntsiab lus hauv zos tsis muaj zog (micropores<100nm)
Roj hauv cov npuas sib txawv sai sai los ntawm thaj tsam toj roob hauv pes
Thaum kawg ua rau npuas sib koom ua ke lossis kev sib tawg
2.} molecular txheej txheem ntawm cov ua npuas tsiaj
Kev sib tw nto deg: Silicone roj lwg me me nyob hauv cov roj-kua interface, tabking kev npaj ntawm foaming tus neeg sawv cev molecules
Txo saum npoo av elasticity: silicone roj zaj duab xis txo gibbs Elastic modulus (tuaj yeem txo mus<1mN/m)
Marangoni muaj kev cuam tshuam hluav taws xob: Tshem tawm cov "kev kho tus kheej" muaj peev xwm tshwm sim los ntawm cov qib siab gradient
Plaub {. cov qauv tshwj xeeb
Tus Kheej Emulsifying Tus Kheej: Muaj kev txhim kho polyether hloov silicone roj (xws li peos), uas tuaj yeem raug tawg nteg ntom nti hauv dej
Hmoov Yam: Adsorbs Silicone Roj ntawm cov neeg nqa khoom ntxeem tau (xws li sio₂, roj thauj khoom tuaj yeem ncav cuag 80%)
Khoom Noj Khoom Noj: Siv USP Qeb Silicone Roj (Viscosity 100-1000 Daim Ntawv Pov Thawj
Cov Hluav Taws Kub Kub: Siv Phenyyl Silicone Roj (Qhov Kub Kuj Kuj> 300 degree) thiab cov lim dej tshwj xeeb
Tsib {. yam cuam tshuam rau kev ua tau zoo
Silicone Roj Viscosity: Nruab Nrab Viscosity ({0}} CST) feem ntau yog qhov zoo tshaj plaws
Qhov loj me me: qhov zoo tshaj plaws yog 1 /10-1}}} / 5 ntawm cov npaus fickness (feem ntau {{μm)
HLUB TSES: Kho raws li cov tshuab sib txawv (cov theem dej feem ntau yuav tsum tau hlb 4-7)
Zeta muaj peev xwm: Cov hom emulsion xav tau kom muaj kev ruaj ntseg ntawm> ± 30 MV
Niaj hnub nimno Silicone defoamers tuaj yeem ua tiav kev tiv thaiv sai (<10 seconds) and long-term antifoaming (>24 teev) ntawm PPM-qib qib ntxiv los ntawm kev tswj hwm cov ntsuas no .
