Dissolution thiab Dispersion txheej txheem ntawm cov nplaim taws Retardants hauv Polyurethane AB Adhesive System

Dissolution thiab Dispersion txheej txheem ntawm cov nplaim taws Retardants hauv Polyurethane AB Adhesive System

Rau kev tawg / tawg ntawm cov nplaim hluav taws kub zoo xws li aluminium hypophosphite (AHP), aluminium hydroxide (ATH), zinc borate, thiab melamine cyanurate (MCA) hauv polyurethane AB nplaum, cov kauj ruam tseem ceeb suav nrog pretreatment, stepwise dispersion, thiab nruj tswj cov dej noo. Hauv qab no yog cov txheej txheem ntxaws (rau cov qauv hluav taws kub-retardant; lwm cov qauv tuaj yeem hloov kho raws li).

I. Cov Ntsiab Cai

1. "Dissolution" yog qhov tseem ceeb dispersion: Cov nplaim hluav taws kub nyhiab yuav tsum tau sib cais nyob rau hauv cov polyol (A-component) los tsim ib qho kev ncua.
2. Pretreatment ntawm nplaim hluav taws retardants: daws teeb meem ntawm ya raws, agglomeration, thiab reactivity nrog isocyanates.
3. Stepwise ntxiv: Ntxiv cov ntaub ntawv nyob rau hauv kev txiav txim ntawm qhov ntom thiab particle loj kom tsis txhob muaj cov concentrations hauv zos.
4. Kev tswj cov dej kom nruj: Cov dej siv cov isocyanate (-NCO) hauv B-tiv thaiv, ua rau kev kho tsis zoo.

II. Cov txheej txheem ua haujlwm kom ntxaws (raws li 100 qhov chaw polyol hauv A-component)

Kauj Ruam 1: Nplaim Retardant Pretreatment (24 teev ua ntej)

• Aluminium Hypophosphite (AHP, 10 qhov chaw):
  • Txheej txheej nrog silane coupling tus neeg sawv cev (KH-550) lossis titanate coupling tus neeg sawv cev (NDZ-201):
    • Sib tov 0.5 qhov chaw coupling tus neeg sawv cev + 2 qhov chaw anhydrous ethanol, do rau 10 min rau hydrolysis.
    • Ntxiv AHP hmoov thiab do ntawm kev kub ceev (1000 rpm) rau 20 min.
    • Qhuav hauv qhov cub ntawm 80 ° C rau 2 xuab moos, tom qab ntawd muab kaw.
• Aluminium Hydroxide (ATH, 25 qhov chaw):
  • Siv submicron-loj, silane-hloov ATH (piv txwv li, Wandu WD-WF-20). Yog tias tsis hloov kho, kho zoo ib yam li AHP.
• MCA (6 qhov) & Zinc Borate (4 qhov chaw):
  • Qhuav ntawm 60 ° C rau 4 xuab moos kom tshem tawm cov dej noo, tom qab ntawd sieve los ntawm 300-mesh screen.

Kauj Ruam 2: A-Component (Polyol Sab) Cov Txheej Txheem Dispersion

1. Base Mixing:
   • Ntxiv 100 qhov chaw polyol (piv txwv li, polyether polyol PPG) rau hauv lub thawv qhuav.
   • Ntxiv 0.3 qhov chaw polyether-modified polysiloxane leveling tus neeg saib xyuas (xws li BYK-333).
2. Tsawg-Speed ​​Pre-Dispersion:
   • Ntxiv cov nplaim hluav taws xob hauv kev txiav txim: ATH (25 qhov chaw) → AHP (10 qhov chaw) → zinc borate (4 qhov chaw) → MCA (6 qhov chaw).
   • Do ntawm 300-500 rpm rau 10 min kom txog thaum tsis muaj hmoov qhuav.
3. High-Shear Dispersion:
   • Hloov mus rau qhov kub ceev disperser (≥1500 rpm) rau 30 min.
   • Tswj kub ≤50 ° C (kom tiv thaiv polyol oxidation).
4. Kev Sib Tsoo & Kho Kom Zoo (Critical!):
   • Dhau los ntawm peb-yob zeb los yog pob tawb xuab zeb zeb 2-3 zaug kom txog thaum fineness ≤30μm (kuaj ntawm Hegman gauge).
5. Viscosity Kho & Defoaming:
   • Ntxiv 0.5 qhov chaw hydrophobic fumed silica (Aerosil R202) los tiv thaiv kev daws teeb meem.
   • Ntxiv 0.2 qhov chaw silicone defoamer (xws li Tego Airex 900).
   • Do ntawm 200 rpm rau 15 min rau degassing.

Kauj Ruam 3: B-Component (Isocyanate Side) Kev Kho Mob

• Ntxiv 4-6 qhov chaw molecular sieve (piv txwv li, Zeochem 3A) rau cov khoom siv B (piv txwv li, MDI prepolymer) rau kev nqus dej noo.
• Yog tias siv cov kua phosphorus nplaim taws retardants (tsawg-viscosity xaiv), ncaj qha sib tov rau hauv cov khoom B thiab do rau 10 min.

Kauj Ruam 4: AB Component Mixing & Curing

• Kev sib xyaw ua ke: Ua raws li tus qauv AB nplaum qub (piv txwv li, A: B = 100:50).
• Mixing txheej txheem:
  • Siv ob lub ntiaj teb sib tov sib xyaw lossis cov raj sib xyaw zoo li qub.
  • Sib tov rau 2-3 feeb kom txog thaum sib tov (tsis muaj hlua).
• Curing tej yam kev mob:
  • Chav tsev kub kho: 24 teev (ntev los ntawm 30% vim nplaim hluav taws kub nqus).
  • Accelerated curing: 60 ° C / 2 teev ( siv tau rau cov txiaj ntsig tsis muaj npuas).

III. Cov Ntsiab Cai Tswj Cov Ntsiab Lus

IV. Lwm txoj kev Dispersion (tsis muaj cov cuab yeej sib tsoo)

1. Pob milling pretreatment:
   • Sib tov cov nplaim hluav taws thiab polyol ntawm 1: 1 piv, pob zeb rau 4 teev (zirconia pob, 2 hli loj).
2. Masterbatch txoj kev:
   • Npaj 50% nplaim retardant masterbatch (polyol li cov cab kuj), ces dilute ua ntej siv.
3. Ultrasonic dispersion:
   • Siv ultrasonication (20kHz, 500W, 10 min) rau premixed slurry (tsim rau cov khoom me me).

V. Cov lus pom zoo rau kev siv

1. Kev sim me me ua ntej: Kev sim nrog 100g ntawm A-cov khoom, tsom rau viscosity stability (24h hloov <10%) thiab kho ceev.
2. Nplaim retardant ntxiv raws txoj cai:
   • "Hnyav ua ntej, lub teeb tom qab; zoo ua ntej, ntxhib tom qab" → ATH (hnyav) → AHP (zoo) → zinc borate (nruab nrab) → MCA (lub teeb / ntxhib).
3. Kev daws teeb meem kub ntxhov:
   • Sudden viscosity nce: Ntxiv 0.5% propylene glycol methyl ether acetate (PMA) kom dilute.
   • Kev kho tsis zoo: Ntxiv 5% hloov kho MDI (xws li Wanhua PM-200) rau cov khoom siv B.