Synthesis Thiab Technical Properties Ntawm Polycarboxylic Acid Superplasticizers
Sep 29, 2024
Polycarboxylate superplasticizersyog tsim los nrog cov khoom siv dag zog molecular, featuring ib qho kev faib ua feem ntawm cov khoom siv tau zoo thiab qhov hnyav molecular ntau yam. Raws li qhov tshwm sim, polycarboxylate superplasticizers tsis tsuas yog muab cov dej txo qis dua thiab kev khaws cia ntev dua piv rau lwm cov superplasticizers, tab sis lawv kuj yuav tsum tau siv me me.
Vim lawv cov txiaj ntsig tseem ceeb, polycarboxylate superplasticizers tau dhau los ua tus neeg sawv cev ntawm ntau yam tshiab ntawm cov dej reducers uas tab tom tsim thoob ntiaj teb. Hauv Nyij Pooj, polycarboxylate superplasticizers twb tau hloov naphthalene-based superplasticizers hauv kev lag luam pob zeb.
Polycarboxylate-based high-performance superplasticizers yog lub cim thib peb ntawm cov dej ua haujlwm siab, ua raws li cov superplasticizers zoo tib yam uas sawv cev los ntawm cov ntoo calcium thiab cov high-efficiency superplasticizers sawv cev los ntawm naphthalene. Tam sim no lawv yog cov qib siab tshaj plaws nyob hauv lub ntiaj teb, muaj cov ntsiab lus thev naus laus zis siab tshaj plaws, cov ntawv thov kev cia siab zoo tshaj plaws, thiab kev ua haujlwm zoo tshaj plaws. DH-4005 hom polycarboxylate high-performance superplasticizer sawv cev rau cov thev naus laus zis ntawm cov dej txo cov khoom lag luam niaj hnub no. Kev sib piv nrog cov khoom zoo sib xws hauv tsev thiab thoob ntiaj teb tau pom tias polycarboxylate high-performance superplasticizers ua tiav qib siab thoob ntiaj teb hauv kev ntsuas kev ua tau zoo thiab kev ua haujlwm zoo.
Rough Synthesis:Dissolve acrylic acid, sodium methallyl sulfonate, ammonium persulfate, thiab polyethylene glycol allyl monomer hauv dej deionized los ua 20% aqueous tov. Nyob rau hauv ib lub khob peb-caj dab nruab nrog ib tug stirrer, reflux condenser, thiab tus pas ntsuas kub, ntxiv cov monomers thiab pib hauv batch. Tom qab qhov sib ntxiv ua tiav, tuav cov tshuaj tiv thaiv ntawm 75 degree rau ib lub sijhawm. Thaum ua tiav cov tshuaj tiv thaiv, kho cov pH mus rau 7-8 nrog 20% NaOH tov kom tau cov xim daj lossis xim liab-xim av polycarboxylate superplasticizer nrog cov concentration ntawm kwv yees li 20%.
Technical Performance:
| Yam khoom | PC (Standard Hom) | PC (Tshooj Retarding) |
|---|---|---|
| Qhov tshwm sim | Lub teeb xim av kua | Lub teeb xim av kua |
| Qhov ceev (g / ml) | 1.07 ± 0.02 | 1.07 ± 0.02 |
| Khoom Khoom (%) | 20 ± 2 | 20 ± 2 |
| Cement Paste Flowability (Reference Cement) (mm) | Ntau dua lossis sib npaug rau 250 (W/C=0.29) | Ntau dua lossis sib npaug rau 250 (W/C=0.29) |
| pH | 6–8 | 6–8 |
| Cov ntsiab lus chloride ion (%) | Tsawg dua lossis sib npaug rau 0.02 | Tsawg dua lossis sib npaug rau 0.02 |
| Cov ntsiab lus Alkali (Na2O + 0}.658K2O) (%) | Tsawg dua lossis sib npaug rau 0.2 | Tsawg dua lossis sib npaug rau 0.2 |
| Yam khoom | PC (Standard Hom) | PC (Tshooj Retarding) |
|---|---|---|
| Dej txo tus nqi (%) | 25–45 | 25–45 |
| Ntshav qab zib tus nqi (%) | Tsawg dua los yog sib npaug li 20 | Tsawg dua los yog sib npaug li 20 |
| Kev nce qib (mm) | >100 | >100 |
| Kev tuav ruaj ruaj (1h) (mm) | Ntau tshaj los yog sib npaug rau 160 | Ntau tshaj los yog sib npaug rau 160 |
| Cov ntsiab lus cua (%) | 2.0–5.0 | 2.0–5.0 |
| Teem sijhawm sib txawv (min) | Qhov pib pib: -90 rau +90; Kev teeb tsa zaum kawg: -90 rau +90 | Kev teeb tsa thawj zaug: +150; Kev teeb tsa zaum kawg: +150 |
|
Yam khoom |
PC (Standard Hom) | PC (Tshooj Retarding) |
|---|---|---|
| Compressive Strength ratio (%) | 1d: Ntau dua lossis sib npaug rau 180 | Tsis Xav Tau |
| 3d: Ntau dua lossis sib npaug rau 165 | Ntau dua lossis sib npaug li 155 | |
| 7d: Ntau dua lossis sib npaug li 155 | Ntau dua lossis sib npaug li 145 | |
| 28d: Ntau dua lossis sib npaug rau 135 | Ntau dua lossis sib npaug li 130 | |
| Durability | 28d Shrinkage Rate (%) Tsawg dua lossis sib npaug rau 100 | Tsawg dua los yog sib npaug li 100 |
| 200 Txias-Thaw txheeb ze Dynamic Modulus (%) Ntau dua lossis sib npaug rau 60 | Ntau dua lossis sib npaug li 60 | |
| Chloride ion permeability (C) | Tsawg dua los yog sib npaug li 1000 | Tsawg dua los yog sib npaug li 1000 |
| Carbonation Depth Ratio (%) | Tsawg dua los yog sib npaug li 100 | Tsawg dua los yog sib npaug li 100 |
| Hlau Reinforcement Corrosion | Tsis muaj | Tsis muaj |
| Common Dosage (%) | 0.8–1.5% ntawm tag nrho cov ntaub ntawv cementitious | - |
Cov nyhuv txo dej yog lub luag haujlwm tseem ceeb uas ua los ntawm surfactants hauv cov txheej txheem dej ntawm cov cement. Cov dej reducers tuaj yeem txo cov dej siv hauv ib chav tsev yam tsis muaj kev cuam tshuam rau kev ua haujlwm ntawm cov pob zeb; los yog, lawv tuaj yeem txhim kho kev ua haujlwm ntawm cov pob zeb tsis muaj kev hloov pauv kev siv dej; los yog ob qho tib si cuam tshuam tuaj yeem ua tiav ib txhij yam tsis muaj kev hloov pauv huab cua ntawm cov khoom sib xyaw. Tam sim no, tag nrho cov twj tso kua mis dej siv yog surfactants, tshwj xeeb tshaj yog anionic surfactants.
Thaum cov cement tov nrog dej, cov tshuaj tiv thaiv hydration tshwm sim, ua rau qee cov qauv flocculent uas ntxiab ntau cov dej sib tov, yog li txo cov kev ua haujlwm ntawm cov pob zeb tshiab (tseem hu ua workability, uas yog hais txog lub peev xwm ntawm cov pob zeb tshiab kom nyob twj ywm. thiab compact tsis muaj kev sib cais thaum sib tov, thauj, thiab nchuav). Yuav kom tswj tau qhov kev xav tau ua haujlwm thaum lub sijhawm tsim kho, cov dej sib tov yuav tsum tau nce ntxiv raws li qhov xav tau. Txawm li cas los xij, kev nce cov dej tuaj yeem tsim cov voids ntau dhau ntawm cov cement paste qauv, cuam tshuam rau lub cev thiab cov khoom siv ntawm cov pob zeb tawv tawv. Yog tias cov dej ntws tawm tuaj yeem tso tawm, cov dej siv ntawm cov pob zeb yuav raug txo kom tsawg. Los ntawm kev koom ua ke ib qho tsim nyog ntawm cov dej-txo tus neeg sawv cev thaum lub sij hawm kev npaj ua vaj tse, cov nyhuv no tuaj yeem ua tiav zoo.