Impembelelo ye-Emulsion Powder eDispersible kwi-Slurry Structure

I-redispersible latex powder yinto esetyenziswa ngokuqhelekileyo i-organic gelling material efunyenwe ngokutshiza-yomisa i-polymer emulsion nge-polyvinyl alcohol njenge-colloid ekhuselayo. Inokuphinda ihlakazwe ngokulinganayo emanzini ukwenza i-emulsion xa idibana namanzi. Ukongeza i-latex powder enokuphinda isetyenziswe kunokuphucula ukusebenza kodaka oluxutyiweyo lwesamente.

Ngokukhawuleza ukuba izinto ezisekelwe kwi-samente zongezwa nge-latex powder zidibanisa namanzi, i-hydration reaction iqala, kwaye isisombululo se-calcium hydroxide ngokukhawuleza sifikelela kwi-saturation kunye ne-crystals iyancipha, kwaye ngexesha elifanayo, i-crystals ettringite kunye ne-calcium silicate hydrate gels zenziwa. Iinqununu eziqinileyo zifakwe kwi-gel kunye neengqungquthela ze-samente ezingenamanzi. Njengoko i-hydration reaction iqhubeka, iimveliso ze-hydration zanda, kwaye iinqununu ze-polymer ziqokelela ngokuthe ngcembe kwi-capillary pores, zenza i-densely packed layer on the surface of the jel and on unhydrated particles cement particles. Amasuntswana e-polymer ahlanganisiweyo ngokuthe ngcembe azalise i-pores, kodwa kungekhona ngokupheleleyo kwindawo yangaphakathi ye-pores. Njengoko amanzi ayancipha ngakumbi nge-hydration okanye ukomiswa, iinqununu ze-polymer ezifakwe ngokusondeleyo kwi-gel kunye ne-pores coalesce kwifilimu eqhubekayo, eyenza umxube odibeneyo kunye ne-hydrated cement paste kunye nokuphucula i-hydration Bonding yeemveliso kunye ne-aggregates.

Ngenxa yokuba iimveliso ze-hydration ezine-polymers zenza umaleko wokugubungela kwi-interface, inokuchaphazela ukukhula kwe-ettringite kunye ne-coarse calcium hydroxide crystals; kwaye ngenxa yokuba iipolymers zidibanisa kwiifilimu kwi-pores ye-interface transition zone, izinto ezisekelwe kwi-samente ye-polymer Indawo yokutshintsha i-denser. Amaqela asebenzayo kwezinye iimolekyuli ze-polymer nazo ziya kuvelisa ukuphendula okuxhamlayo kunye ne-Ca2 + kunye ne-A13 + kwiimveliso ze-samente ze-samente ukuze zenze iibhondi ezikhethekileyo zebhuloho, ukuphucula isakhiwo somzimba wezinto eziqiniweyo ezisekelwe kwi-samente, ukunciphisa uxinzelelo lwangaphakathi, kunye nokunciphisa isizukulwana se-microcracks.

Njengoko i-gel ye-cement ikhula, amanzi asetyenziswa kwaye iinqununu ze-polymer zigcinwa ngokuthe ngcembe kwiipores. Njengoko i-samente i-hydrated ngakumbi, ukufuma kwi-capillary pores kuncipha, kwaye i-polymer particles aggregate phezu komhlaba we-cement hydration product gel / unhydrated sement particle umxube kunye ne-aggregate, ngaloo ndlela yenze i-close-packed layer kunye ne-pores enkulu ezaliswe. ngamasuntswana epolymer ancamathelayo okanye azincamatheleyo.

I-emulsion ehlakaziweyo ye-latex powder edibeneyo inokwenza ifilimu eqhubekayo engenamanzi (i-polymer network body) emva kokumisa, kwaye lo mzimba ophantsi we-elastic modulus polymer network unokuphucula ukusebenza kwe-samente; ngelo xesha, kwimolekyuli yepolymer Amaqela athile e-polar kwisamente asabela ngokwekhemikhali kunye neemveliso ze-samente ze-hydration ukwenza iibhulorho ezikhethekileyo, ukuphucula isakhiwo somzimba weemveliso ze-samente hydration, kunye nokunciphisa kunye nokunciphisa ukuveliswa kweentanda. Emva kokuba i-latex powder yongezwa kwakhona, umlinganiselo wokuqala we-hydration we-cement uyancipha, kwaye ifilimu ye-polymer ingakwazi ukugoqa ngokuyinxenye okanye ngokupheleleyo i-sement particles, ukwenzela ukuba i-samente ibe ne-hydrated ngokupheleleyo kunye neempawu zayo ezahlukeneyo zinokuphuculwa.