Cellulose ether kusinthidwa simenti slurry

Zotsatira zamitundu yosiyanasiyana ya ma cell a non-ionic cellulose ether pamapangidwe a pore a simenti slurry adaphunziridwa ndi kuyesa kachulukidwe kantchito komanso kuwunika kwa ma macroscopic ndi ma microscopic pore. Zotsatira zikuwonetsa kuti nonionic cellulose ether imatha kuonjezera porosity ya simenti slurry. Pamene mamasukidwe akayendedwe a non-ionic cellulose ether kusinthidwa slurry ndi ofanana, porosity wahydroxyethyl cellulose ether(HEC) slurry yosinthidwa ndi yaying'ono kuposa ya hydroxypropyl methyl cellulose ether (HPMC) ndi methyl cellulose ether (MC) yosinthidwa slurry. Kutsika kwa mamasukidwe akayendedwe/chibale kulemera kwa maselo a HPMC mapadi efa ndi zofanana gulu zili, ang'onoang'ono porosity wa kusinthidwa slurry simenti. Non-ionic mapadi ether akhoza kuchepetsa mavuto padziko madzi gawo ndi kupanga simenti slurry zosavuta kupanga thovu. Non-ayoni mapadi efa mamolekyulu ndi directionally adsorbed pa mawonekedwe mpweya wamadzimadzi a thovu, amenenso kumawonjezera mamasukidwe akayendedwe a simenti slurry gawo ndi timapitiriza luso la simenti slurry kukhazikika thovu.

Mawu ofunikira:nonionic cellulose ether; matope a simenti; Kapangidwe ka pore; Mapangidwe a maselo; Kupanikizika pamwamba; mamasukidwe akayendedwe

Nonionic cellulose ether (yotchedwanso cellulose ether) imakhala ndi makulidwe abwino kwambiri komanso kusunga madzi, ndipo imagwiritsidwa ntchito kwambiri mumatope osakaniza owuma, konkire yodzipangira yokha ndi zida zina zatsopano zopangira simenti. Ma cellulose ether omwe amagwiritsidwa ntchito muzinthu zopangira simenti nthawi zambiri amakhala ndi methyl cellulose ether (MC), hydroxypropyl methyl cellulose ether (HPMC), hydroxyethyl methyl cellulose ether (HEMC) ndi hydroxyethyl cellulose ether (HEC), mwa omwe HPMC ndi HEMC ndi omwe amagwiritsidwa ntchito kwambiri. .

Ma cellulose ether amatha kukhudza kwambiri pore kapangidwe ka simenti slurry. Pourchez et al., kudzera mu mayeso owoneka bwino a kachulukidwe, kuyezetsa kukula kwa pore (njira ya jakisoni wa mercury) ndi kusanthula kwazithunzi za seEM, adatsimikiza kuti ether ya cellulose imatha kukulitsa ma pores okhala ndi mainchesi pafupifupi 500nm ndi ma pores okhala ndi mainchesi pafupifupi 50-250μm. matope a simenti. Kuphatikiza apo, pakuwumitsa simenti yowuma, Kugawa kwa pore kwa masinthidwe otsika a molekyulu HEC osinthidwa simenti ndikofanana ndi slurry wa simenti. Chiwerengero chonse cha pore cholemera kwambiri cha molekyulu ya HEC yosinthidwa simenti ndi yokwera kuposa ya simenti yonyowa, koma yotsika kuposa ya HPMC yosinthidwa simenti ya simenti yomwe imakhala yofanana. Kupyolera mu kuwona kwa SEM, Zhang et al. anapeza kuti HEMC akhoza kwambiri kuonjezera chiwerengero cha pores ndi awiri a 0.1mm mu matope simenti. Anapezanso kudzera mu mayeso a jekeseni wa mercury kuti HEMC ikhoza kuonjezera kuchuluka kwa pore ndi kuchuluka kwa pore awiri a simenti, zomwe zimapangitsa kuwonjezeka kwakukulu kwa ma pores akuluakulu ndi awiri a 50nm ~ 1μm ndi ma pores akuluakulu okhala ndi awiri ochulukirapo. pa 1m. Komabe, kuchuluka kwa pores ndi m'mimba mwake zosakwana 50nm kunachepetsedwa kwambiri. Saric-Coric et al. ankakhulupirira kuti cellulose ether imapangitsa kuti matope a simenti akhale ochuluka kwambiri ndikupangitsa kuti ma macropores achuluke. Jenni et al. adayesa kuchuluka kwa magwiridwe antchito ndikutsimikiza kuti gawo la pore la HEMC losinthidwa simenti linali pafupifupi 20%, pomwe matope oyera a simenti anali ndi mpweya wochepa. Silva et al. anapeza kuti kuwonjezera pa nsonga ziwiri pa 3.9 nm ndi 40 ~ 75nm monga koyera simenti slurry, panalinso nsonga ziwiri pa 100 ~ 500nm ndi wamkulu kuposa 100μm kudzera Mercury jekeseni mayeso. Ma Baoguo et al. anapeza kuti mapadi etere kuchuluka kwa pores zabwino ndi diameters zosakwana 1μm ndi pores lalikulu ndi diameters wamkulu kuposa 2μm mu matope simenti kudzera Mercury jekeseni mayeso. Chifukwa chakuti mapadi efa kumawonjezera porosity wa simenti slurry, kawirikawiri amakhulupirira kuti mapadi efa ali pamwamba ntchito, adzalemeretsa mu mlengalenga ndi madzi mawonekedwe, kupanga filimu, kuti bata ndi thovu mu slurry simenti.

Kupyolera mu kusanthula kwa mabuku omwe ali pamwambawa, zikhoza kuwoneka kuti zotsatira za cellulose ether pa mapangidwe a pore a zipangizo zopangira simenti zalandira chidwi chachikulu. Komabe, pali mitundu yambiri ya etere ya cellulose, mtundu womwewo wa efa wa cellulose, kulemera kwake kwa maselo, zomwe zili mumagulu ndi magawo ena amtundu wa maselo ndizosiyana kwambiri, ndipo ofufuza a m'nyumba ndi akunja pa kusankha kwa mapadi a ether amangogwira ntchito yawo. munda, kusowa koyimira, mapeto ake ndi osapeŵeka "overgeneralization", kotero kuti kufotokoza kwa cellulose ether limagwirira sikuli kozama mokwanira. Mu pepalali, zotsatira za cellulose ether zokhala ndi mamolekyu osiyanasiyana pamapangidwe a pore a simenti slurry zidaphunziridwa ndikuyesa kachulukidwe kowoneka bwino komanso kuwunika kwa ma macroscopic ndi ma microscopic pore.

1. Mayeso

1.1 Zida Zopangira

Simentiyo inali simenti ya P · O 42.5 wamba ya ku Portland yopangidwa ndi Huaxin Cement Co., LTD., momwe mankhwalawo adayeza ndi AXIOS Ad-Vanced wavelength dispersion-mtundu wa X-ray fluorescence spectrometer (PANa - lytical, Netherlands), ndipo mawonekedwe a gawo adayesedwa ndi njira ya Bogue.

Ma cellulose ether anasankha mitundu inayi ya etere yamalonda ya cellulose, motsatana methyl cellulose ether (MC), hydroxypropyl methyl cellulose ether (HPMC1, HPMC2) ndi hydroxyethyl cellulose ether (HEC), HPMC1 kapangidwe ka maselo ndi HPMC2 ofanana, koma kukhuthala kwake ndi kochepa kwambiri kuposa HPMC2 , Ndiye kuti, kuchuluka kwa maselo a HPMC1 ndi ocheperako kuposa a HPMC2. Chifukwa cha zofanana za hydroxyethyl methyl cellulose ether (HEMc) ndi HPMC, HEMCs sanasankhidwe mu phunziroli. Pofuna kupewa kutengera chinyezi pazotsatira zoyezetsa, ma cellulose ether onse amawotcha pa 98℃ kwa 2h musanagwiritse ntchito.

Kukhuthala kwa cellulose ether kunayesedwa ndi NDJ-1B rotary viscosimeter (Shanghai Changji Company). Mlingo woyeserera woyeserera (chiŵerengero cha misa ya cellulose ether kumadzi) chinali 2.0%, kutentha kunali 20 ℃, ndipo kusinthasintha kunali 12r/min. Kuthamanga kwapamtunda kwa cellulose ether kunayesedwa ndi njira ya mphete. Chida choyesera chinali JK99A automatic tensiometer (Shanghai Zhongchen Company). Kuchuluka kwa yankho la mayeso kunali 0.01% ndipo kutentha kunali 20 ℃. Zamagulu a cellulose ether amaperekedwa ndi wopanga.

Malinga ndi mamasukidwe akayendedwe, kukangana pamwamba ndi zili gulu zili mapadi efa, pamene ndende yankho ndi 2.0%, ndi mamasukidwe akayendedwe chiŵerengero cha HEC ndi HPMC2 njira ndi 1: 1.6, ndi mamasukidwe akayendedwe chiŵerengero cha HEC ndi MC njira ndi 1: 0.4, koma mu mayesowa, madzi simenti chiŵerengero ndi 0,35, pazipita simenti chiŵerengero ndi 0,6%, misa chiŵerengero cha mapadi efa madzi ndi pafupifupi 1.7%, zosakwana 2.0%, ndi synergistic zotsatira za simenti slurry pa mamasukidwe akayendedwe, kotero Kusiyana kwamakayendedwe a HEC, HPMC2 kapena MC kusinthidwa simenti slurry ndikochepa.

Malinga ndi mamasukidwe akayendedwe, kukangana padziko ndi gulu zili mu cellulose ether, kuthamanga kwapamtunda kwa cellulose ether iliyonse kumakhala kosiyana. Ma cellulose ether ali ndi magulu onse a hydrophilic (magulu a hydroxyl ndi ether) ndi magulu a hydrophobic (methyl ndi glucose carbon ring), ndi surfactant. Ma cellulose ether ndi osiyana, mtundu ndi zomwe zili m'magulu a hydrophilic ndi hydrophobic ndizosiyana, zomwe zimapangitsa kuti pakhale zovuta zosiyanasiyana.

1.2 Njira zoyesera

Mitundu sikisi ya simenti slurry anakonzedwa, kuphatikizapo koyera simenti slurry, anayi mapadi efa (MC, HPMCl, HPMC2 ndi HEC) kusinthidwa slurry simenti ndi 0,60% simenti chiŵerengero ndi HPMC2 kusinthidwa simenti slurry ndi 0.05% simenti chiŵerengero. Ref, MC - 0,60, HPMCl - 0.60, Hpmc2-0.60. HEC 1-0.60 ndi hpMC2-0.05 zikuwonetsa kuti chiŵerengero cha simenti ya madzi ndi 0.35.

Simenti slurry choyamba malinga ndi GB/T 17671 1999 "simenti matope mphamvu mayeso njira (ISO njira)" anapanga 40mm × 40mm × 160mm prisms chipika mayeso, pansi pa chikhalidwe cha 20 ℃ losindikizidwa kuchiritsa 28d. Pambuyo poyeza ndi kuwerengera kuchuluka kwake kowonekera, idang'ambika ndi nyundo yaying'ono, ndipo mawonekedwe a dzenje lalikulu lapakati pa chipika choyesera adawonedwa ndikujambulidwa ndi kamera ya digito. Nthawi yomweyo, tiziduswa tating'ono ta 2.5 ~ 5.0mm zidatengedwa kuti ziwonedwe ndi maikulosikopu owoneka bwino (HIROX microscope yamavidiyo atatu-dimensional) ndikusanthula maikulosikopu ya elekitironi (JSM-5610LV).

2. Zotsatira za mayeso

2.1 Kuchulukana kowonekera

Malinga ndi kachulukidwe kowoneka bwino kwa matope a simenti osinthidwa ndi ma etha osiyanasiyana a cellulose, (1) kuchulukira kowoneka bwino kwa matope a simenti ndikokwera kwambiri, komwe ndi 2044 kg/m³; The kachulukidwe zoonekeratu za mitundu inayi ya mapadi etere kusinthidwa slurry ndi chiŵerengero simenti 0,60% anali 74% ~ 88% wa koyera simenti slurry, kusonyeza kuti mapadi efa anachititsa kuwonjezeka porosity wa slurry simenti. (2) Pamene chiŵerengero cha simenti ndi simenti ndi 0,60%, zotsatira za ma etha osiyanasiyana a cellulose pa porosity ya simenti slurry ndizosiyana kwambiri. The viscosity of HEC, HPMC2 ndi MC modified simenti slurry ndi ofanana, koma kachulukidwe kowoneka bwino kwa HEC kusinthidwa simenti slurry ndi apamwamba kwambiri, kusonyeza kuti porosity wa HEC kusinthidwa simenti slurry ndi yaying'ono kuposa HPMc2 ndi Mc modified simenti slurry ndi visco zofanana visco. . HPMc1 ndi HPMC2 zili ndi gulu lofanana, koma kukhuthala kwa HPMCl ndikotsika kwambiri kuposa kwa HPMC2, ndipo kachulukidwe ka simenti yosinthidwa HPMCl ndi yayikulu kwambiri kuposa slurry ya simenti yosinthidwa ya HPMC2, zomwe zikuwonetsa kuti zomwe zili pagulu ndizofanana. , kutsika kwa kukhuthala kwa cellulose ether, kumachepetsa porosity ya slurry yosinthidwa simenti. (3) Pamene chiŵerengero cha simenti ndi simenti ndi chochepa kwambiri (0.05%), kachulukidwe kake ka HPMC2-modified simenti slurry ali pafupi kwambiri ndi slurry ya simenti yoyera, kusonyeza kuti zotsatira za cellulose ether pa porosity ya simenti. slurry ndi yaying'ono kwambiri.

2.2 Macroscopic pore

Malinga ndi gawo zithunzi za mapalo etere kusinthidwa simenti slurry anatengedwa ndi kamera digito, koyera simenti slurry ndi wandiweyani, pafupifupi palibe pores looneka; Mitundu inayi ya cellulose etha yosinthidwa slurry ndi 0,60% simenti chiŵerengero onse ali ndi pores macroscopic, kusonyeza kuti mapadi etha kumabweretsa kuwonjezeka simenti slurry porosity. Mofanana ndi zotsatira za kuyesa kachulukidwe kowoneka bwino, zotsatira za mitundu yosiyanasiyana ya cellulose ether ndi zomwe zili pa porosity ya simenti slurry ndizosiyana kwambiri. The viscosity ya HEC, HPMC2 ndi MC modified slurry ndi ofanana, koma porosity ya HEC yosinthidwa slurry ndi yaying'ono kuposa ya HPMC2 ndi MC modified slurry. Ngakhale HPMC1 ndi HPMC2 zili ndi gulu lofanana, HPMC1 yosinthidwa slurry yokhala ndi mamasukidwe otsika imakhala ndi porosity yaying'ono. Pamene chiŵerengero cha simenti ndi simenti cha HPMc2 slurry yosinthidwa ndi yaying'ono kwambiri (0.05%), chiwerengero cha ma macroscopic pores chimawonjezeka pang'ono kuposa cha slurry choyera cha simenti, koma chimachepetsedwa kwambiri kuposa cha HPMC2 slurry yosinthidwa ndi 0.60% simenti-ku. - chiŵerengero cha simenti.

2.3 Pore ya Microscopic

4. Mapeto

(1) Ma cellulose ether amatha kuonjezera porosity ya slurry ya simenti.

(2) Zotsatira za cellulose etha pa porosity wa simenti slurry ndi osiyana maselo dongosolo magawo ndi osiyana: pamene mamasukidwe akayendedwe a mapaipi etere kusinthidwa simenti slurry ndi ofanana, porosity wa HEC kusinthidwa simenti slurry ndi laling'ono kuposa la HPMC ndi MC kusinthidwa matope a simenti; Kutsika kwa mamasukidwe akayendedwe/chibale kulemera kwa maselo a HPMC mapadi efa ndi zofanana gulu zili, m'munsi porosity wake kusinthidwa slurry simenti.

(3) Pambuyo powonjezera mapadi etere mu simenti slurry, mavuto padziko madzi gawo yafupika, kuti simenti slurry n'zosavuta kupanga thovu ine mapalo etha mamolekyu malangizo adsorption mu kuwira mpweya mpweya mawonekedwe, kusintha mphamvu ndi kulimba kwa The kuwira madzi filimu adsorption mu kuwira mpweya mpweya mawonekedwe, kusintha mphamvu ya kuwira madzi filimu ndi kulimbikitsa luso matope amphamvu kukhazikika kuwira.