Cellulose ether pamatope odzipangira okha

Zotsatira zahydroxypropyl methyl cellulose etherpa fluidity, kusungidwa kwa madzi ndi mphamvu yomangirira ya matope odzipangira okha adaphunziridwa. Zotsatira zikuwonetsa kuti HPMC imatha kukonza bwino kusungidwa kwamadzi kwamatope odzipangira okha komanso kuchepetsa kusasinthika kwamatope. Kumayambiriro kwa HPMC kumatha kupititsa patsogolo mphamvu yomangira yamatope, koma mphamvu yopondereza, mphamvu yosunthika ndi madzimadzi zimachepetsedwa. Kuyesa kwa kusiyana kwa SEM kunachitika pazitsanzo, ndipo zotsatira za HPMC pakubweza, kusungirako madzi ndi mphamvu ya matope zidafotokozedwanso kuchokera ku hydration course ya simenti pa 3 ndi 28 masiku.

Mawu ofunikira:matope odzipangira okha; Cellulose ether; Kuchuluka kwa madzi; Kusunga madzi

0. Chiyambi

Mtondo wodziyimira pawokha ukhoza kudalira kulemera kwake kuti upange maziko athyathyathya, osalala komanso olimba pa gawo lapansi, kuti akhazikike kapena kumangiriza zida zina, ndipo amatha kupanga gawo lalikulu la zomangamanga zapamwamba kwambiri, chifukwa chake, kuchuluka kwamadzimadzi ndikokwanira. mbali yofunika kwambiri ya matope odzikweza okha; Makamaka ngati voliyumu yayikulu, kulimbitsa wandiweyani kapena kusiyana kochepera 10 mm kubweza kapena kulimbikitsa kugwiritsa ntchito grouting. Kuphatikiza pa madzi abwino, matope odzipangira okha ayenera kukhala ndi madzi osungiramo madzi ndi mphamvu zomangira, palibe chodabwitsa cha kupatukana kwa magazi, komanso kukhala ndi makhalidwe a adiabatic ndi kutentha kochepa.

Nthawi zambiri, matope odzipangira okha amafunikira madzi abwino, koma madzi enieni a slurry simenti nthawi zambiri amakhala 10 ~ 12 cm. Mtondo wodziyimira pawokha ukhoza kukhala wodzipangira okha, ndipo nthawi yoyika koyamba ndi yayitali ndipo nthawi yomaliza yomaliza imakhala yochepa. Cellulose ether ndi chimodzi mwazowonjezera zazikulu za matope osakaniza okonzeka, ngakhale kuti kuchuluka kwake kuli kochepa kwambiri, koma kumatha kusintha kwambiri ntchito yamatope, kumatha kusintha kusasinthasintha kwamatope, kugwira ntchito, kugwira ntchito, kugwirizanitsa ntchito ndi kusunga madzi, ntchito yofunika kwambiri m'munda wa matope okonzeka osakaniza.

1. Zopangira ndi njira zofufuzira

1.1 Zida Zopangira

(1) P · O 42.5 simenti wamba.

(2) Mchenga zakuthupi: Xiamen anatsuka mchenga wa m'nyanja, kukula kwa tinthu ndi 0.3 ~ 0.6mm, madzi ndi 1% ~ 2%, kuyanika kochita kupanga.

(3) Cellulose ether: hydroxypropyl methyl cellulose ether ndi chopangidwa ndi hydroxyl m'malo mwa methoxy ndi hydroxypropyl, motero, ndi mamasukidwe akayendedwe a 300mpa·s. Pakali pano, ether yambiri ya cellulose yomwe imagwiritsidwa ntchito ndi hydroxypropyl methyl cellulose ether ndi hydroxyethyl methyl cellulose ether.

(4) superplasticizer: polycarboxylic acid superplasticizer.

(5) Redispersible latex ufa: HW5115 mndandanda wopangidwa ndi Henan Tiansheng Chemical Co., Ltd. ndi redispersible latex ufa wopangidwa ndi VAC/VeoVa.

1.2 Njira zoyesera

Kuyesedwa kunachitika molingana ndi muyezo wamakampani JC/T 985-2005 "Simenti-based Self-leveling Mortar for Ground Use". Nthawi yoikika idatsimikiziridwa potengera nthawi yokhazikika komanso nthawi yoyika JC/T 727 simenti phala. Self-leveling mortar specimen kupanga, kupindika ndi kukakamiza mphamvu kuyesa kumatanthawuza ku GB/T 17671. Njira yoyesera ya mphamvu zomangira: Chipilala choyesera matope cha 80mmx80mmx20mm chimakonzedwa pasadakhale, ndipo zaka zake zadutsa 28d. Pamwamba pamakhala khwimbi, ndipo madzi odzaza pamwamba amapukutidwa pambuyo pakunyowetsa kwa mphindi 10. Chidutswa choyesera chamatope chimatsanuliridwa pamtunda wopukutidwa ndi kukula kwa 40mmx40mmx10mm. Mphamvu ya bond imayesedwa pa zaka zopanga.

Scanning electron microscopy (SEM) idagwiritsidwa ntchito kusanthula morphology ya zinthu zosimbidwa mu slurry. Mu phunziroli, njira yosakaniza ya zipangizo zonse za ufa ndi: choyamba, zipangizo za ufa za chigawo chilichonse zimasakanizidwa mofanana, kenaka zimawonjezeredwa kumadzi omwe akufunidwa kuti asakanike yunifolomu. Zotsatira za cellulose ether pamatope odzipangira okha zidawunikidwa ndi mphamvu, kusunga madzi, fluidity ndi mayeso a microscopic a SEM.

2. Zotsatira ndi kusanthula

2.1 Kuyenda

Cellulose ether imakhudza kwambiri kusungidwa kwa madzi, kusasinthasintha komanso kupanga matope odziyimira pawokha. Makamaka ngati matope odziyimira pawokha, madzi amadzimadzi ndi amodzi mwazinthu zazikulu zowunikira momwe matope odzipangira okha amagwirira ntchito. Pamaziko owonetsetsa kuti matope apangidwe bwino, kusungunuka kwa matope kungasinthidwe mwa kusintha zomwe zili mu cellulose ether.

Ndi kuchuluka kwa cellulose ether okhutira. The fluidity ya matope amachepetsa pang'onopang'ono. Pamene mlingo ndi 0,06%, fluidity ya matope amachepetsa ndi oposa 8%, ndipo pamene mlingo ndi 0,08%, fluidity amachepetsa ndi oposa 13.5%. Pa nthawi yomweyo, ndi kutambasuka kwa m`badwo, mkulu mlingo limasonyeza kuti kuchuluka kwa mapadi ether ayenera kulamulidwa mkati osiyanasiyana osiyanasiyana, kwambiri mlingo adzabweretsa zotsatira zoipa pa matope fluidity. Madzi ndi simenti mu matope amapanga slurry woyera kudzaza mchenga, ndi kukulunga mchengawo kuti agwire ntchito yopaka mafuta, kuti matope azikhala ndi madzi enaake. Ndi kuyambika kwa cellulose ether, zomwe zili m'madzi aulere m'dongosolo zimachepetsedwa, ndipo nsanjika yophimba pakhoma lakunja la mchenga imachepetsedwa, motero amachepetsa kutuluka kwa matope. Chifukwa cha kufunikira kwa matope odzipangira okha omwe ali ndi madzi ambiri, kuchuluka kwa cellulose ether kuyenera kuyendetsedwa mosiyanasiyana.

2.2 Kusunga Madzi

Kusungidwa kwamadzi mumatope ndi chizindikiro chofunikira choyezera kukhazikika kwa zigawo mumatope osakanikirana a simenti. Kuonjezera mlingo woyenerera wa cellulose ether kungathandize kuti madzi asungidwe mumatope. Pofuna kuti hydration reaction ya zinthu cementing mokwanira, wololera kuchuluka kwa mapadi ether akhoza kusunga madzi mu matope kwa nthawi yaitali kuonetsetsa kuti hydration anachita wa cementing zakuthupi angathe kuchitidwa mokwanira.

Ma cellulose ether angagwiritsidwe ntchito ngati chosungira madzi chifukwa maatomu a okosijeni pa ma hydroxyl ndi ether amalumikizana ndi mamolekyu amadzi kuti apange ma hydrogen bond, kupanga madzi aulere kukhala madzi ophatikizana. Zitha kuwoneka kuchokera ku ubale womwe ulipo pakati pa zomwe zili mu cellulose ether ndi kuchuluka kwa kusungira madzi mumatope kuti kuchuluka kwa kusungirako madzi mumatope kumawonjezeka ndi kuchuluka kwa zomwe zili mu cellulose ether. Mphamvu yosungira madzi ya cellulose ether ingalepheretse gawo lapansi kuti lisatenge madzi ochulukirapo komanso othamanga kwambiri, ndikuletsa kutuluka kwa madzi, motero kuonetsetsa kuti chilengedwe cha slurry chimapereka madzi okwanira kuti simenti ikhale ndi simenti. Palinso maphunziro omwe amasonyeza kuti kuwonjezera pa kuchuluka kwa cellulose ether, kukhuthala kwake (kulemera kwa maselo) kumakhudzanso kwambiri kusungirako madzi amatope, kukula kwakukulu kwa viscosity, ndi bwino kusunga madzi. Ma cellulose ether okhala ndi mamasukidwe a 400 MPa·S nthawi zambiri amagwiritsidwa ntchito ngati matope odziyimira pawokha, omwe amatha kuwongolera magwiridwe antchito amatope ndikuwongolera kulimba kwa matope. Pamene mamasukidwe akayendedwe amaposa 40000 MPa · S, ntchito yosungira madzi sikulinso bwino kwambiri, ndipo siyenera kudzipangira matope.

Mu phunziro ili, zitsanzo za matope okhala ndi cellulose ether ndi matope opanda cellulose ether adatengedwa. Gawo la zitsanzo anali 3d zaka zitsanzo, ndi mbali ina ya zitsanzo zaka 3d anali muyezo anachiritsa 28d, ndiyeno mapangidwe simenti hydration mankhwala mu zitsanzo anayesedwa ndi SEM.

The hydration mankhwala a simenti mu akusowekapo chitsanzo matope zitsanzo pa zaka 3d ndi kuposa anthu chitsanzo ndi mapadi efa, ndipo pa zaka 28d, mankhwala hydration mu chitsanzo ndi mapadi efa ndi kutali kwambiri kuposa zitsanzo akusowekapo. Ma hydration oyambirira amadzi amachedwa chifukwa pali filimu yovuta yosanjikiza yopangidwa ndi cellulose ether pamwamba pa particles simenti kumayambiriro. Komabe, ndi kuwonjezereka kwa msinkhu, ndondomeko ya hydration imayenda pang'onopang'ono. Panthawiyi, kusungidwa kwa madzi a cellulose ether pa slurry kumapangitsa kuti pakhale madzi okwanira mu slurry kuti akwaniritse zofuna za hydration reaction, zomwe zimathandiza kuti hydration ipite patsogolo. Chifukwa chake, pali zinthu zambiri za hydration mu slurry pambuyo pake. Kunena zoona, pali madzi ambiri aulere mumtsuko wopanda kanthu, womwe ungathe kukhutitsa madzi ofunikira poyambira simenti. Komabe, ndi kupita patsogolo kwa hydration process, gawo lamadzi muzachitsanzo limadyedwa ndi kuyambika kwa hydration, ndipo gawo lina limatayika ndi evaporation, zomwe zimapangitsa kuti madzi asakwane mu slurry pambuyo pake. Chifukwa chake, zinthu za 3d hydration zomwe zili mu zitsanzo zopanda kanthu ndizochulukirapo. Kuchuluka kwa zinthu za hydration ndizocheperako poyerekeza ndi kuchuluka kwa zinthu za hydration mu zitsanzo zomwe zili ndi cellulose ether. Chifukwa chake, potengera zinthu za hydration, zikufotokozedwanso kuti kuwonjezera kuchuluka koyenera kwa cellulose ether kumatope kumatha kusintha kusungidwa kwamadzi kwa slurry.

2.3 Kukhazikitsa nthawi

Ma cellulose ether ali ndi vuto linalake lochepetsa mumatope, ndikuwonjezeka kwa cellulose ether. Nthawi yoyika matope imatalika. Kuchepetsa kwa cellulose ether kumakhudzana mwachindunji ndi mawonekedwe ake. Ma cellulose ether ali ndi mawonekedwe a mphete a shuga, omwe amatha kupanga shuga wa calcium molecular zovuta chipata ndi ayoni a calcium mu simenti ya hydration solution, amachepetsa kuchuluka kwa ayoni a calcium mu simenti ya hydration induction period, kuteteza mapangidwe ndi mpweya wa Ca (OH) 2 ndi mchere wa calcium. makhiristo, kuti achedwetse njira ya hydration ya simenti. Kuchedwetsa kwa cellulose etha pa slurry ya simenti makamaka kumadalira kuchuluka kwa m'malo mwa alkyl ndipo alibe ubale wochepa ndi kulemera kwake kwa maselo. Kuchepa kwa digiri ya alkyl, kuchuluka kwa hydroxyl, kumapangitsanso kuchedwetsa. L. Semitz et al. amakhulupirira kuti ma cellulose ether mamolekyu anali makamaka adsorbed pa mankhwala hydration monga C - S - H ndi Ca(OH)2, ndipo kawirikawiri adsorbed pa clinker choyambirira mchere. Kuphatikizidwa ndi kusanthula kwa SEM kwa simenti ya hydration, imapezeka kuti cellulose ether ili ndi vuto linalake, ndipo kukweza kwa cellulose ether, ndipamenenso zikuwonekeratu kuti kuchepa kwa filimu yovuta kwambiri pakuyambira kwa simenti kumayambira, zoonekeratu kuchedwetsa zotsatira.

2.4 Mphamvu ya Flexural ndi mphamvu yopondereza

Nthawi zambiri, mphamvu ndi imodzi mwazofunikira zowunika za simenti zopangidwa ndi simenti zomwe zimachiritsa zosakaniza. Kuphatikiza pa ntchito yothamanga kwambiri, matope odziyimira pawokha ayeneranso kukhala ndi mphamvu zopondereza komanso mphamvu zosunthika. Mu phunziro ili, 7 ndi 28 masiku compressive mphamvu ndi flexural mphamvu ya matope opanda kanthu wosakanizidwa ndi mapadi ether anayesedwa.

Ndi kuchuluka kwa cellulose ether okhutira, matope compressive mphamvu ndi flexural mphamvu yafupika mu matalikidwe osiyana, zili ang'onoang'ono, chikoka pa mphamvu si zoonekeratu, koma ndi zili oposa 0,02%, mphamvu imfa mlingo kukula ndi zoonekeratu. Choncho, pogwiritsira ntchito cellulose ether kuti apititse patsogolo kusungirako madzi amatope, komanso kuganizira kusintha kwa mphamvu.

Zifukwa za kuponderezedwa kwa matope ndi kuchepa kwa mphamvu ya flexural. Ikhoza kuwunikidwa kuchokera ku mbali zotsatirazi. Choyamba, mphamvu zoyamba ndi kulimbitsa simenti mwachangu sizinagwiritsidwe ntchito mu phunziroli. Pamene matope owuma adasakanizidwa ndi madzi, tinthu tating'ono ta cellulose etere mphira wa mphira poyamba adakongoletsedwa pamwamba pa tinthu tating'ono ta simenti kuti tipange filimu ya latex, yomwe inachedwetsa hydration ya simenti ndikuchepetsa mphamvu yoyambirira ya matrix amatope. Kachiwiri, pofuna kutengera malo ogwirira ntchito pokonzekera matope odziyimira pawokha pamalopo, zitsanzo zonse mu kafukufukuyu sizinagwedezeke pokonzekera ndi kuumba, ndipo zidadalira kudzikweza. Chifukwa cha mphamvu yosungira madzi ya cellulose ether mumatope, ma pores ambiri adasiyidwa mu matrix pambuyo pouma matope. Kuwonjezeka kwa porosity mumatope ndi chifukwa chofunika kwambiri cha kuchepa kwa mphamvu yoponderezedwa ndi kusinthasintha kwa matope. Komanso, pambuyo kuwonjezera mapadi etero mu matope, zili kusintha polima mu pores matope ukuwonjezeka. Pamene matrix akanikizidwa, polima yosinthika imakhala yovuta kuchita gawo lolimba lothandizira, zomwe zimakhudzanso mphamvu ya matrix pamlingo wina.

2.5 Mphamvu yolumikizana

Cellulose ether imakhudza kwambiri matope omangirira ndipo amagwiritsidwa ntchito kwambiri pofufuza ndikukonzekera matope odzipangira okha.

Pamene zili mu cellulose ether ndi pakati pa 0,02% ndi 0.10%, mphamvu chomangira matope mwachionekere bwino bwino, ndi mphamvu chomangira pa 28 masiku ndi apamwamba kwambiri kuposa 7 masiku. Ma cellulose ether amapanga chatsekedwa polima filimu pakati simenti hydration particles ndi madzi gawo dongosolo, amene amalimbikitsa madzi ambiri mu polima filimu kunja particles simenti, amene amathandiza kuti wathunthu hydration wa simenti, kuti patsogolo chomangira mphamvu ya phala. pambuyo kuumitsa. Pa nthawi yomweyo, mlingo woyenera wa mapadi etere timapitiriza plasticity ndi kusinthasintha matope, amachepetsa rigidity wa kusintha zone pakati matope ndi gawo lapansi mawonekedwe, amachepetsa kuzembera maganizo pakati pa mawonekedwe, ndi kumawonjezera kugwirizana kwenikweni pakati matope ndi gawo lapansi mu digiri inayake. Chifukwa cha kukhalapo kwa cellulose etha mu slurry simenti, wapadera interfacial kusintha zone ndi interfacial wosanjikiza aumbike pakati particles matope ndi mankhwala hydration. Chosanjikiza chapakatichi chimapangitsa kuti malo osinthira azitha kukhala osinthika komanso osakhazikika, kotero kuti matope amakhala ndi mphamvu zomangirira mwamphamvu.

3. Pomaliza ndi Kukambirana

Ma cellulose ether amatha kupititsa patsogolo kusungidwa kwamadzi mumatope odzipangira okha. Ndi kuwonjezeka kwa kuchuluka kwa cellulose ether, kusunga madzi kwa matope kumawonjezeka pang'onopang'ono, ndipo madzi amadzimadzi ndi nthawi yoyika amachepetsedwa mpaka kufika pamlingo wina. Kusungirako madzi ochuluka kwambiri kumawonjezera kulimba kwa slurry, zomwe zingapangitse kuti matope owuma awonongeke kwambiri. Mu phunziroli, mphamvu inachepa kwambiri pamene mlingo unali pakati pa 0.02% ndi 0.04%, ndipo kuchuluka kwa cellulose ether, kumapangitsanso kuti kuchepetsako kukuwonekera. Chifukwa chake, mukamagwiritsa ntchito cellulose ether, ndikofunikira kuganizira mozama zamakina amadzimadzi odziyimira pawokha, kusankha koyenera kwa mlingo ndi mphamvu ya synergistic pakati pake ndi zida zina zamankhwala.

Kugwiritsiridwa ntchito kwa cellulose ether kungachepetse mphamvu yopondereza ndi mphamvu yosunthika ya slurry ya simenti, ndikusintha mphamvu yomangira yamatope. Kusanthula zifukwa kusintha mphamvu, makamaka chifukwa cha kusintha yaying'ono mankhwala ndi dongosolo, pa dzanja limodzi, mapadi efa mphira ufa particles choyamba adsorbed padziko simenti particles, mapangidwe latex filimu, kuchedwa hydration wa simenti, zomwe zidzachititsa imfa ya oyambirira mphamvu slurry; Komano, chifukwa cha filimu kupanga zotsatira ndi zotsatira madzi posungira, ndi yabwino hydration wathunthu simenti ndi kusintha mphamvu chomangira. Wolembayo amakhulupirira kuti mitundu iwiri ya kusintha kwa mphamvuyi imakhalapo mu malire a nthawi yoikika, ndipo kutsogola ndi kuchedwa kwa malirewa kungakhale mfundo yovuta yomwe imayambitsa kukula kwa mitundu iwiri ya mphamvu. Kuphunzira mozama komanso mwadongosolo pa mfundo yovutayi kudzakhala kothandiza kuwongolera bwino ndikuwunika njira ya hydration ya zinthu zosimbidwa mu slurry. Ndizothandiza kusintha kuchuluka kwa cellulose ether ndikuchiritsa nthawi molingana ndi kufunikira kwa zinthu zamakina amatope, kuti muwonjezere magwiridwe antchito amatope.