Hnub Kawg:17,Lub Xya Hli,2023

Feem ntau cov teeb meem tom qab kev tsim kho ntawm sab hauv phab ntsa putty hmoov yog peeling thiab whitening.Yuav kom nkag siab txog cov laj thawj rau kev tshem tawm ntawm cov phab ntsa sab hauv putty hmoov, nws yog ib qho tsim nyog yuav tsum xub nkag siab txog cov khoom siv raw khoom thiab cov txheej txheem kho ntawm sab hauv phab ntsa putty hmoov.Tom qab ntawd, raws li qhov dryness, dej nqus, kub, thiab huab cua qhuav ntawm phab ntsa thaum lub sij hawm tsim kho, txheeb xyuas cov laj thawj tseem ceeb rau kev tshem tawm ntawm cov phab ntsa sab hauv putty hmoov thiab siv cov kev sib raug zoo los daws qhov teeb meem ntawm putty hmoov tev.

Ib, Cov khoom siv raw khoom tseem ceeb ntawm sab hauv phab ntsa putty hmoov:

Cov khoom tseem ceeb tshaj plaws ntawm sab hauv phab ntsa putty hmoov muaj xws li: inorganic bonding material (grey calcium), fillers (hnyav calcium hmoov, talcum hmoov, thiab lwm yam), thiab polymer additives (HPMC, polyvinyl cawv, roj hmab hmoov, thiab lwm yam).Ntawm lawv, sab hauv phab ntsa putty hmoov feem ntau tsis ntxiv cov cement dawb lossis tsuas yog ntxiv cov cement dawb me ntsis.Redispersible latex hmoov muaj cov nyhuv me me ntawm qhov ntau npaum li cas, yog li nws feem ntau tsis siv rau sab hauv phab ntsa putty hmoov vim yog teeb meem nqi lossis tsis tshua siv.

Yog li vim qhov teeb meem nrog cov qauv ntawm sab hauv phab ntsa putty hmoov nws tus kheej:

1. Inorganic bonding cov ntaub ntawv, xws li qis ntxiv ntawm grey calcium thiab substandard zoo ntawm grey calcium;

2. Qhov sib ntxiv ntawm cov khoom sib txuas hauv cov khoom siv polymer uas tsis tshua muaj siab lossis tsis ua raws li cov qauv zoo yuav ua rau cov phab ntsa sab hauv putty hmoov poob.

二 、 Kho mechanism ntawm sab hauv phab ntsa putty hmoov:

Kev kho ntawm sab hauv phab ntsa putty hmoov tsuas yog nyob ntawm kev sib koom ua ke ntawm cov kua qaub calcium hmoov, HPMC thiab lwm yam polymer additives nyob rau hauv wetting tej yam kev mob rau solidify, tsim ib zaj duab xis, thiab stabilize lub curing txheej txheem.

Lub hauv paus ntsiab lus hardening ntawm grey calcium hmoov:

Qhuav thiab hardening: Thaum lub sij hawm scraping txheej txheem, ib tug loj npaum li cas ntawm cov dej evaporates los ntawm grey calcium hmoov, ua ib tug loj network ntawm zoo tib yam pores nyob rau hauv lub slurry.Cov dej dawb uas nyob hauv lub qhov hws, vim yog qhov nro ntawm cov dej, tsim cov capillary siab, ua rau grey calcium hmoov hmoov ntau compact, yog li tau txais lub zog.Thaum cov slurry qhuav ntxiv, cov nyhuv no kuj tseem muaj zog.Crystallization hardening: Highly dispersed colloidal hais nyob rau hauv slurry yog sib cais los ntawm diffusion txheej ntawm cov hais.Raws li cov ntsiab lus dej maj mam txo qis, cov txheej txheem diffusion maj mam thins, thiab yog li cov colloidal hais ua ke nyob rau hauv qhov kev txiav txim ntawm molecular rog, tsim ib tug spatial network ntawm condensed lug, yog li tau txais lub zog.Carbon hardening: Lub slurry absorbs CO2 roj los ntawm huab cua, tsim calcium carbonate uas yog insoluble nyob rau hauv dej.Cov txheej txheem no hu ua carbonation ntawm slurry.Cov kev sib cuam tshuam yog raws li nram no:

Ca(OH)2+CO2+H2O →CaCO3+(n+1)H2O

Lub generated calcium carbonate crystals coexist nrog ib leeg los yog nrog calcium hydroxide hais, ua ib tug nruj intertwined siv lead ua network, yog li txhim kho lub zog ntawm slurry.Tsis tas li ntawd, vim yog cov khoom ntim me ntsis ntawm calcium carbonate piv rau calcium hydroxide, cov tawv tawv grey calcium hmoov slurry nyhav dua.3, Tom qab cov hmoov putty yog siv rau ntawm phab ntsa, cov dej hauv lub putty feem ntau ploj los ntawm peb txoj kev:

Cov dej evaporation ntawm qhov chaw ntawm lub putty thaum grey calcium thiab dawb cement reacts nyob rau hauv lub absorbent putty hmoov ntawm lub hauv paus phab ntsa nto.3. Qhov cuam tshuam ntawm kev tsim kho ntawm cov hmoov shedding ntawm putty hmoov:

Cov laj thawj rau cov hmoov poob los ntawm kev tsim kho muaj xws li: kev saib xyuas tsis zoo ua rau cov putty qhuav sai heev thiab tsis muaj zog txaus;Lub hauv paus ntawm phab ntsa yog qhuav dhau, ua rau lub putty poob dej sai;Tshaj thickness ntawm putty nyob rau hauv ib batch.