Kawm Txog Polycarboxylic Superplasticizer Polyether Macromonomer

Tsab ntawv xov xwm no piav qhia luv luv txog qhov kev txhim kho tam sim no ntawm kev lag luam hauv tsev polyether macromonomer, qhia txog cov hom tseem ceeb thiab kev lag luam ntawm cov khoom siv polycarboxylic superplasticizer macromonomers uas twb muaj lawm, thiab tshuaj xyuas lawv qhov zoo, qhov tsis zoo, thiab cov lus qhia kev txhim kho los ntawm kev xav ntawm cov qauv sib txawv. Tsis tas li ntawd, ib hom tshiab ntawm polycarboxylic superplasticizer macromonomer, ethylene glycol monovinyl poly (ethylene glycol) ether (EPEG), tau qhia.

Polycarboxylic superplasticizer (PCE) sawv cev rau tiam tshiab ntawm cov khoom sib xyaw ua ke, feem ntau hu ua peb tiam ntawm cov khoom ua tau zoo superplasticizers. Piv nrog rau yav dhau los tiam ntawm naphthalene-based superplasticizers, PCE muaj kev txo cov dej ntau dua thiab zoo dua cement adaptability. Tsis tas li ntawd, cov txheej txheem tsim khoom ntawm PCE ua rau tsis muaj cov txheej txheem dej khib nyiab lossis cov pa khib nyiab, ua rau cov khoom siv tsis zoo.

PCE yog ib qho amphiphilic polymer, feem ntau ua ke los ntawm copolymerization ntawm qhov kawg-kawg ob daim ntawv cog lus poly (ethylene glycol) ether macromonomers thiab unsaturated carboxylic acid monomers nyob rau hauv lub xub ntiag ntawm ib tug pib. Thaum lub sij hawm cov tshuaj tiv thaiv, cov vinyl pawg ntawm macromonomers thiab monomers tsim cov pob txha polymer, thaum cov polyethylene glycol ntu ntawm macromonomers tsim cov saw hlau, raws li tau piav qhia hauv daim duab 1.

Piv nrog rau cov tshuaj superplasticizers, PCE qhov tseem ceeb tshaj plaws yog nws cov qauv molecular customizable. Cov unsaturated ob daim ntawv cog lus nyob rau hauv macromonomer terminal pawg tsim cov polycarboxylate qaum ntawm polymerization. Cov pab pawg ua haujlwm xws li -COO-Na thiab -SO3-Na ncaj qha txuas mus rau lub nraub qaum pab kom "ntau-point anchoring" ntawm cov cement particle nto. Polyethylene glycol sab chains tsim ib txheej txheej polymer los ntawm hydrogen bonding nrog dej molecules ntawm cov cement particle nto. Qhov no steric hindrance nyhuv disperses cov cement hais, ua tiav cov dej-txo cov nyhuv. Yog li ntawd, kev txhim kho hauv PCE vam khom ntau ntawm kev tsim cov macromonomers tshiab. Cov qauv tsim kho tshiab hauv macromonomers tuaj yeem txhim kho cov txheej txheem tsim khoom thiab kev ua haujlwm ntawm PCE.

1. Keeb kwm kev loj hlob

Cov khoom PCE thaum ntxov yog ester-raws li, nrog methoxy poly (ethylene glycol) ether (MPEG) ua cov macromonomer, raws li qhia hauv daim duab 2. Synthesizing PCE los ntawm hom macromonomer no yuav tsum muaj ob kauj ruam: esterification thiab polymerization, ua rau cov txheej txheem complex. Cov ester-based macromonomers tau maj mam hloov los ntawm ether-based macromonomers.

Ether-based macromonomers tam sim no tswj hwm kev lag luam. Cov macromonomers no tau tsim los ntawm ethoxylation ntawm cov qauv sib txawv ntawm cov qauv molecular (unsaturated alcohols), uas ua rau poly (ethylene glycol) ethers nrog terminal vinyl pawg. Raws li cov qauv ntawm cov pib molecules, cov macromonomers no tuaj yeem muab faib ua peb hom: 3-carbon alcohol-based (allyl poly(ethylene glycol) ether - APEG), 4-carbon thiab {{5} } carbon cawv-raws li (isobutenyl poly (ethylene glycol) ether - HPEG, isopentenyl poly (ethylene glycol) ether - TPEG), thiab 2+2 thiab 2+4 vinyl ether-based macromonomers (EPEG, VPEG), raws li qhia hauv daim duab 2.

2. Kev thov tam sim no

Nrog rau txoj kev loj hlob sai ntawm kev lag luam polycarboxylic superplasticizer, polyether macromonomer sector hauv Suav teb kuj tau ua qhov tseem ceeb. Ob lub peev xwm ntau lawm thiab cov khoom tsim tawm ntawm polyether macromonomers tau nce ntxiv, mus txog qhov siab tshaj plaws hauv xyoo 2017. Table 1 qhia tag nrho cov muag khoom thiab cov qauv ntawm polyether macromonomers los ntawm 2013 txog 2017.

Raws li tau piav qhia hauv Table 1, txawm hais tias kev lag luam polyether macromonomer hauv Suav teb tau txhim kho sai, nws tseem ntsib ntau yam kev nyuaj. Ntawm qhov tod tes, HPEG thiab TPEG cov khoom lag luam suav rau feem ntau ntawm cov macromonomers uas twb muaj lawm, uas ua rau muaj cov khoom lag luam zoo sib xws. Tsis tas li ntawd, kev muab cov neeg pib rau HPEG thiab TPEG macromonomers tseem yog ib feem ntawm kev xa tawm, tshwj xeeb tshaj yog cov 5-carbon alcohol initiators, uas yog los ntawm Nyiv Kuraray thiab Lub Tebchaws Yelemees BASF. Ntawm qhov tod tes, kev khiav hauj lwm tus nqi ntawm cov chaw tsim khoom macromonomer feem ntau qis, ua rau muaj teeb meem loj dhau ntawm kev lag luam.