Mphamvu ya Hydroxypropyl Methyl Cellulose Ether pa Makhalidwe a Machine Sprayed Cement Mortar

Cellulose ether ndi chowonjezera chofunikira mumatope ophulika ndi makina. Zotsatira za ma viscosities anayi osiyanasiyana a hydroxypropyl methylcellulose (HPMC) pa kusungirako madzi, kachulukidwe, mpweya, makina opangira makina ndi kukula kwa pore kugawa matope ophulika ndi makina. Kafukufuku wasonyeza kuti: HPMC ikhoza kupititsa patsogolo ntchito yosungira madzi mumatope, ndipo madzi osungira madzi amatha kupitirira 90% pamene kuchuluka kwa HPMC ndi 0.15%. Zoonekeratu kwambiri; mpweya wa matope ukuwonjezeka ndi kuwonjezeka kwa HPMC okhutira: HPMC mwachiwonekere kuchepetsa mawotchi katundu wa simenti matope, koma chiŵerengero chopinda cha matope adzawonjezeka; kukula kwa pore kwa matope kudzawonjezeka kwambiri pambuyo powonjezera HPMC, Kuchuluka kwa mabowo ovulaza ndi mabowo angapo ovulaza kunakula kwambiri.

Mawu ofunikira: matope; hydroxypropyl methylcellulose ether; kusunga madzi; kugawa kukula kwa pore

0. Mawu oyamba

M'zaka zaposachedwa, ndi kupita patsogolo kosalekeza kwa mafakitale ndi kupititsa patsogolo kwaukadaulo, kudzera pakuyambitsa ndi kukonza makina opopera matope akunja, ukadaulo wa kupopera mbewu ndi pulasitala wamakina wakula kwambiri m'dziko lathu. Makina opopera mbewu mankhwalawa ndi osiyana ndi matope wamba, omwe amafunikira kusungitsa madzi kwapamwamba, madzimadzi abwino komanso ntchito zina zotsutsa-sagging. Kawirikawiri, ether ya cellulose imawonjezeredwa kumatope, omwe hydroxypropyl methylcellulose Plain ether (HPMC) amagwiritsidwa ntchito kwambiri. Ntchito zazikulu za HPMC mu matope ndi: mphamvu yabwino yosungira madzi, kukhuthala ndi viscosifying ndi kusintha kwa rheological. Komabe, zofooka za HPMC sizinganyalanyazidwe. HPMC ali ndi mpweya-entraining zotsatira, amene adzachititsa zambiri zolakwika mkati ndi kuchepetsa kwambiri mawotchi zimatha matope. Pepalali limaphunzira momwe HPMC imakhudzira kuchuluka kwa kusungidwa kwa madzi, kachulukidwe, mpweya komanso makina amakina amatope kuchokera ku mawonekedwe a macroscopic, ndikuwunika momwe HPMC imakhudzira pore ya matope kuchokera ku mawonekedwe ang'onoang'ono.

1. Mayeso

1.1 Zopangira

Simenti: P·O42.5 simenti, 28d flexural ndi compressive mphamvu zake ndi 6.9 ndi 48.2 MPa motero; mchenga: Chengde zabwino mtsinje mchenga, 40-100 mauna; cellulose ether: hydroxypropyl mowa wopangidwa ndi kampani ku Hebei Methyl cellulose ether, ufa woyera, kukhuthala kwadzina 40, 100, 150, 200 Pa·S: Madzi: madzi apampopi oyera.

1.2 Njira yoyesera

Malinga ndi JGJ/T 105-2011 "Malamulo Omanga Opopera Ndi Kupaka Pamakina", kusagwirizana kwa matope ndi 80 ~ 120mm, ndipo kuchuluka kwa madzi kumaposa 90%. Pachiyeso ichi, chiŵerengero cha laimu-mchenga chimayikidwa pa 1: 5, kusasinthasintha kumayendetsedwa pa (93).±2) mm, ndipo cellulose ether imapangidwa kunja, ndipo mlingo wake umawerengedwa molingana ndi misa ya simenti. Zofunikira za matope monga kunyowa, kuchuluka kwa mpweya, kuchuluka kwa madzi osungira, komanso kusasinthasintha kumayesedwa molingana ndi JGJ 70-2009 "Njira Zoyesera Zazinthu Zoyambira Zomangamanga", ndipo mpweya wake umayesedwa ndikuwerengedwa molingana ndi kachulukidwe njira. Mayesero okonzekera, osinthasintha komanso okakamiza a zitsanzozo anachitidwa ponena za GB/T 17671-1999 "Njira Zoyesera Kulimba kwa Mchenga wa Simenti Wamatope (ISO Method)". Kukula kwa pore kunayesedwa ndi mercury porosimetry. Chitsanzo cha mercury porosimeter chinali AUTOPORE 9500, ndipo miyeso yoyezera inali 5.5 nm mpaka 360μm. Mayeso a 4 okwana adayesedwa. 0, 0.1%, 0.2%, 0.3% (nambala ndi A, B, C, D).

2. Zotsatira ndi Kusanthula

2.1 Zotsatira za HPMC pa kuchuluka kwa kusunga madzi amatope a simenti

Kusunga madzi kumatanthauza kuthekera kwa matope kusunga madzi. Mu makina opopera matope, kuwonjezera palulose ether kumatha kukhalabe chinyezi, kuchepetsa kuchuluka kwa magazi, ndikukwaniritsa zofunikira za hydration zokwanira zopangira simenti.

Kuchokera ku zotsatira za HPMC pa kuchuluka kwa madzi osungiramo matope, zikhoza kuwoneka kuti ndi kuwonjezeka kwa HPMC, kuchuluka kwa madzi osungiramo madzi kumawonjezeka pang'onopang'ono. Ma curve a cellulose ether okhala ndi viscosities ya 100, 150 ndi 200 Pa·s ndizofanana. Zomwe zili 0.05% mpaka 0.15%, kuchuluka kwa madzi osungirako kumawonjezeka motsatira. Zomwe zili ndi 0.15%, kuchuluka kwa madzi osungirako kumakhala kwakukulu kuposa 93%..Pambuyo pa 20%, kuchulukirachulukira kwa kusungirako madzi kumakhala kosalekeza, kusonyeza kuti kuchuluka kwa HPMC kuli pafupi ndi machulukitsidwe. Mphamvu yopindika ya kuchuluka kwa HPMC yokhala ndi kukhuthala kwa 40 Pa·s pa mlingo wosungira madzi ndi pafupifupi mzere wowongoka. Pamene kuchuluka kwake kuli kwakukulu kuposa 0.15%, kuchuluka kwa madzi osungiramo matope kumakhala kochepa kwambiri kusiyana ndi mitundu itatu ya HPMC yokhala ndi kukhuthala kofanana. Nthawi zambiri amakhulupirira kuti njira yosungiramo madzi ya cellulose ether ndi: gulu la hydroxyl pa molekyulu ya cellulose ether ndi atomu ya okosijeni pa chomangira cha ether chidzalumikizana ndi molekyulu yamadzi kupanga chomangira cha haidrojeni, kuti madzi aulere azikhala omangika. , motero kusewera bwino kusunga madzi; Amakhulupiriranso kuti interdiffusion pakati mamolekyu madzi ndi mapadi etero maselo unyolo amalola mamolekyu madzi kulowa mkati mwa mapalo etere macromolecular unyolo ndi kugonjera mphamvu zomangira mphamvu, potero kuwongolera madzi posungira simenti slurry. Kusungidwa bwino kwa madzi kumatha kupangitsa kuti matope azikhala osakanikirana, osakhala osavuta kusiyanitsa, ndikupeza magwiridwe antchito osakanikirana, ndikuchepetsa kuvala kwamakina ndikuwonjezera moyo wa makina opopera matope.

2.2 Zotsatira za HPMC pa kachulukidwe ndi mpweya wamatope a simenti

Kuchokera ku chikoka cha ma viscosities osiyana ndi Mlingo wa HPMC pa kachulukidwe matope, tingaone kuti pamene mlingo wa HPMC ndi 0-0.20%, kachulukidwe matope amachepetsa kwambiri ndi kuwonjezeka kwa HPMC mlingo, kuchokera 2050 kg/m.³ mpaka 1650kg/m³ , kutsika ndi pafupifupi 20%; HPMC ikadutsa 0.20%, kuchepa kwa kachulukidwe kumakhala kosalala. Poyerekeza mitundu inayi ya HPMC yokhala ndi ma viscosity osiyanasiyana, zitha kuwoneka kuti kumtunda kwa mamasukidwe akayendedwe, kumachepetsa kachulukidwe ka matope; kachulukidwe zokhotakhota za matope ndi viscosities wosanganiza 150 ndi 200 Pa s HPMC kwenikweni zimadutsana, kusonyeza kuti monga mamasukidwe akayendedwe a HPMC akupitirirabe kuwonjezeka, kachulukidwe matope sikulinso kuchepa.

Kuchokera ku chikoka cha ma viscosities osiyanasiyana ndi Mlingo wa HPMC pamlengalenga wamatope, zitha kuwoneka kuti kusintha kwa mpweya wamatope kumasiyana ndi kuchuluka kwa matope. Mpweya wa mpweya pafupifupi umakwera molunjika; pamene zinthu za HPMC zimaposa 0.20%, zomwe zili mumlengalenga sizisintha, kusonyeza kuti mpweya wodutsa mumatope uli pafupi ndi machulukitsidwe. Mphamvu yolowera mpweya ya HPMC yokhala ndi kukhuthala kwa 150 ndi 200 Pa·s ndi yayikulu kuposa ya HPMC yokhala ndi kukhuthala kwa 40 ndi 100 Pa·s.

Mphamvu yolowera mpweya ya cellulose ether imatsimikiziridwa makamaka ndi kapangidwe kake ka maselo. Ma cellulose ether ali ndi magulu onse a hydrophilic (hydroxyl, ether groups) ndi magulu a hydrophobic (magulu a methyl, mphete za glucose), ndipo ndi surfactant. , imakhala ndi ntchito yapamtunda, motero imakhala ndi mphamvu yolowera mpweya. Kumbali imodzi, mpweya woyambitsidwa ukhoza kukhala ngati mpira wonyamula mumatope, kupititsa patsogolo ntchito yamatope, kuonjezera voliyumu, ndikuwonjezera kutulutsa, zomwe zimapindulitsa kwa wopanga. Koma Komano, mpweya-entraining zotsatira kumapangitsa kuti mpweya wa matope ndi porosity pambuyo kuumitsa, kuchititsa kuwonjezeka pores zoipa ndi kuchepetsa kwambiri makina katundu. Ngakhale HPMC ili ndi mphamvu yolowetsa mpweya, siyingalowe m'malo mwa wothandizira mpweya. Komanso, pamene HPMC ndi mpweya-entraining wothandizila ntchito nthawi yomweyo, mpweya-entraining wothandizira akhoza kulephera.

2.3 Zotsatira za HPMC pamakina amatope a simenti

Kuchokera ku 28d flexural mphamvu ndi 28d compressive mphamvu, zikhoza kuwoneka kuti pamene kuchuluka kwa HPMC ndi 0.05% yokha, mphamvu ya flexural ya matope imachepa kwambiri, yomwe ili pafupi ndi 25% yotsika kuposa ya sampuli yopanda kanthu popanda HPMC, ndi mphamvu yopondereza ikhoza kukhala Fikirani 65% ya zitsanzo zopanda kanthu. 80%. Pamene zili HPMC kuposa 0.20%, mlingo wa kuchepa mphamvu flexural ndi compressive mphamvu ya matope si zoonekeratu. The mamasukidwe akayendedwe a HPMC ali ndi zotsatira zochepa pa makina zimatha matope. HPMC imayambitsa tinthu tating'onoting'ono tating'onoting'ono ta mpweya, ndipo mphamvu yolowera mpweya pamatope imawonjezera porosity yamkati ndi pores zovulaza zamatope, zomwe zimapangitsa kuchepa kwakukulu kwa mphamvu zopondereza komanso mphamvu zosinthika. Chifukwa china cha kuchepa kwa mphamvu ya matope ndi mphamvu yosungira madzi ya cellulose ether, yomwe imasunga madzi mumatope owuma, ndipo chiŵerengero chachikulu cha madzi-binder chimabweretsa kuchepa kwa mphamvu ya chipika choyesera. Pakuti makina zomangamanga matope, ngakhale mapadi ether akhoza kwambiri kuonjezera mlingo madzi posungira matope ndi kusintha workability ake, ngati kuchuluka ndi lalikulu kwambiri, izo kwambiri zimakhudza mawotchi zimatha matope, kotero ubale pakati pa awiri ayenera kuyeza momveka.

Kuchokera pakupindika kwa masiku 28, zitha kuwoneka kuti pakuwonjezeka kwa zomwe zili mu HPMC, kuchuluka kwathunthu kwa matope kumawonetsa kuchulukirachulukira, komwe kumakhala ubale wamzera. Ichi ndi chifukwa anawonjezera mapadi etero anayambitsa ambiri thovu mpweya, kuchititsa zofooka zambiri mkati matope, chifukwa chakuthwa kuchepa compressive mphamvu ya matope, ndipo ngakhale mphamvu flexural komanso amachepetsa kumlingo wakutiwakuti; koma cellulose ether imatha kusintha kusinthasintha kwa matope ndikukana Mphamvu yopinda ndi yabwino, zomwe zimapangitsa kuti kuchepa kuchedwe. Poganizira mozama, zotsatira zophatikizana ziwirizi zimabweretsa kuwonjezeka kwa chiŵerengero chopinda.

2.4 Zotsatira za HPMC pakukula kwa pore kwa matope

Miyendo yogawa kukula kwa pore ya magulu anayi a zitsanzo A, B, C ndi D adayesedwa ndi mercury intrusion porosimetry.

Malinga ndi kagawo ka pore kagawidwe ka pore, kukula kwa pore kukula ndi magawo osiyanasiyana a zitsanzo za AD, HPMC imakhudza kwambiri kapangidwe ka matope a simenti:

(1) Pambuyo powonjezera HPMC, kukula kwa pore kwa matope a simenti kumawonjezeka kwambiri. Pa poto yogawa kukula kwa pore, dera la chithunzicho limasunthira kumanja, ndipo mtengo wa pore womwe umagwirizana ndi mtengo wake umakulirakulira. Komanso kuchokera ku ziwerengero za pore kukula kwa pore ndi kukula kwapakati pore muzotsatira zoyesa za magawo osiyanasiyana owerengera, zitha kuwoneka kuti kukula kwapakatikati kwa matope a simenti pambuyo powonjezera HPMC ndi yayikulu kwambiri kuposa yachitsanzo chopanda kanthu, ndipo mu chitsanzo chokhala ndi 0.3% mlingo Kutsegula kwamtengo wapatali ndi madongosolo a 2 apamwamba kuposa a chitsanzo chopanda kanthu.

(2) Wu Zhongwei et al. adagawa ma pores mu konkriti mu mitundu inayi, yomwe ili yopanda vuto (≤20 nm), ma pores ochepa owopsa (20-100 nm), ma pores owopsa (100-200 nm) ndi ma pores ambiri owopsa (≥200 nm). 200 nm). Kuchokera paziwerengero za kukula kwa pore ndi zotsatira za mayeso a magawo osiyanasiyana owerengera, zitha kuwoneka kuti kuchuluka kwa ma pores osavulaza kapena ma pores ocheperako kumachepetsedwa kwambiri, ndipo kuchuluka kwa ma pores owopsa kapena ma pores owopsa kumawonjezeka pambuyo powonjezera HPMC. Ma pores osavulaza kapena osavulaza a zitsanzo popanda HPMC ali pafupifupi 49.4%, ndipo ma pores osavulaza kapena osavulaza amachepetsedwa kwambiri atawonjezera HPMC. Kutengera mlingo wa 0.1% mwachitsanzo, ma pores osavulaza kapena osavulaza amachepetsedwa pafupifupi 45%. , kuchuluka kwa ma pores owopsa kuposa 10μm kuchuluka pafupifupi 9 nthawi.

3) Kuzungulira kwa pore wapakatikati, pafupifupi pore m'mimba mwake, voliyumu yeniyeni ya pore ndi malo enieni apansi samatsatira lamulo losintha kwambiri ndi kuwonjezeka kwa zinthu za HPMC, zomwe zingakhale zokhudzana ndi kufalikira kwakukulu kwa kusankha kwachitsanzo mu mayeso a jekeseni wa mercury. Koma ponseponse, kuchuluka kwa pore wapakatikati, kuchuluka kwa pore ndi kuchuluka kwapore kwachitsanzo chosakanizidwa ndi HPMC kumawonjezeka poyerekeza ndi zitsanzo zopanda kanthu, pomwe malo enieniwo amachepa.

3. Mapeto

(1) Kuchuluka kwa madzi osungiramo madzi kumawonjezeka ndi kuwonjezeka kwa HPMC. Ma curve a cellulose ether okhala ndi viscosities ya 100, 150 ndi 200 Pa·S ndizofanana, ndipo kuchuluka kwa madzi osungirako ndi kwakukulu kuposa 93% pomwe zomwe zili ndi 0.15%. Pamene zili 40 Pa·s cellulose ether ndi wamkulu kuposa 0.15%, kuchuluka kwa madzi posungirako ndikotsika kuposa mitundu itatu ina ya mamasukidwe a HPMC.

(2) Kuchuluka kwa matope kumachepa pang'onopang'ono ndi kuwonjezeka kwa HPMC, ndipo zomwe zili ndi 0.05%. Kuchepa kwa kachulukidwe ndikowonekera kwambiri pa 0,20%, pafupifupi 20%; pamene zomwe zili pamwamba pa 0,20%, kachulukidwe kameneka sikamasintha; mpweya wa matope umawonjezeka ndi kuwonjezeka kwa HPMC.

(3) Kuwonjezeka kwa zinthu za HPMC mwachiwonekere kumachepetsa mphamvu zamakina amatope a simenti, koma chiŵerengero chofanana cha matope chidzawonjezeka, ndipo kusinthasintha kwa matope kudzakhala bwino.

(4) Pambuyo powonjezera HPMC, kukula kwa pore kwa matope kumawonjezeka kwambiri, ndipo gawo la ma pores ovulaza ndi ma pores angapo ovulaza amakula kwambiri. Zitsanzo zomwe zili ndi 0.1% HPMC zidachepetsedwa pafupifupi 45% poyerekeza ndi zitsanzo zopanda kanthu zopanda kapena zovulaza, komanso kuchuluka kwa ma pores owopsa kwambiri kuposa 10.μm kuchuluka pafupifupi 9 zina.