dziwitsani
Hydroxypropyl methylcellulose (HPMC) ndi efa ya cellulose yomwe imagwiritsidwa ntchito kwambiri m'mafakitale osiyanasiyana monga chakudya, mankhwala, ndi zomangamanga monga thickener, emulsifier, and stabilizer. M'makampani omanga, HPMC imagwiritsidwa ntchito ngati chowonjezera pazinthu zopangira simenti kuti akwaniritse zinthu zomwe amafunikira monga kugwira ntchito, kusunga madzi komanso kulimba. Kafukufuku wapeza kuti kuwonjezera HPMC kuzinthu zopangira simenti kumachedwetsa kayendedwe ka simenti, ndipo pamapeto pake zimakhudza kukula kwamphamvu kwa zida zopangira simenti.
Zotsatira za HPMC pa simenti hydration
Cement hydration ndizovuta zomwe zimachitika m'madzi ndi tinthu tating'ono ta simenti. Panthawi ya hydration, tinthu tating'ono ta simenti timachita ndi madzi kuti tipange zinthu zosiyanasiyana za hydration, zomwe zimathandizira kulimbitsa mphamvu ya zida za simenti. Kafukufuku wapeza kuti kuwonjezera kwa HPMC kuzinthu zopangira simenti kumatha kuchedwetsa simenti, motero kusintha kuchuluka kwa kukula kwa mphamvu.
Chimodzi mwa zifukwa zazikulu zochedwetsa simenti hydration ndi katundu wosungira madzi wa HPMC. HPMC ndi hydrophilic polima kuti zimatenga madzi ndi kutupa kupanga gel osakaniza dongosolo. HPMC ikawonjezeredwa kuzinthu zopangira simenti, imatenga madzi kuchokera kusakaniza, motero imachepetsa madzi aulere omwe amafunikira kuthira simenti. Izi nazonso zimachepetsa njira ya hydration, monga momwe simenti imachitira ndi madzi kumafuna madzi okwanira.
Chinthu chinanso chomwe chimapangitsa kuti kuchedwa kwa simenti kumayendetsedwe ndi ma adsorption a HPMC pamwamba pa tinthu tating'ono ta simenti. HPMC ali mkulu kuyanjana kwa particles simenti chifukwa polarity ake. Iwo akhoza adsorbed pamwamba pa simenti particles ndi kupanga chotchinga thupi kuchepetsa kukhudzana mamolekyu madzi ndi simenti particles. Izi nazonso zimachepetsa momwe simenti imagwirira ntchito ndi madzi, zomwe zimapangitsa kuti simenti ikhale yochedwa.
Kuphatikizika kwa HPMC kuzinthu zopangira simenti kudzakhudzanso ma nucleation ndi crystal kukula kwa zinthu za hydration. Kutsekemera kwa simenti kumaphatikizapo kupanga magawo osiyanasiyana a crystalline, monga calcium silicate hydrate (CSH) ndi calcium hydroxide (CH). HPMC imatha kuletsa kukula kwa nucleation ndi crystal ya ena mwa magawowa, ndikuchepetsanso kutsika kwa simenti.
Njira ya kuchedwa kwa simenti hydration
Njira yayikulu yomwe HPMC imachedwetsera simenti kuti ikhale ndi madzi ndi kupanga chotchinga pakati pa tinthu ta simenti ndi madzi. HPMC ikamwazikana m'madzi, imapanga matrix ngati gel omwe amatha kuyika tinthu tating'ono ta simenti ndikuchepetsa kupezeka kwa madzi aulere a simenti. Izi nazonso zimachepetsa momwe simenti imagwirira ntchito ndi madzi, zomwe zimayambitsa kuchedwa kwa kukula kwa mphamvu za zinthu zopangira simenti.
Njira ina ndiyo kutengera kwa HPMC pamwamba pa tinthu ta simenti. HPMC ali mkulu kuyanjana kwa particles simenti chifukwa polarity ake. Iwo akhoza adsorbed padziko simenti particles ndi kupanga chotchinga thupi kuchepetsa kukhudzana mamolekyu madzi ndi simenti particles. Izi zimachepetsanso kuyamwa kwa simenti ndi madzi.
HPMC imathanso kuyanjana ndi magawo osiyanasiyana a simenti, monga ayoni a calcium, potero imakhudza ma nucleation ndi kukula kwa crystal ya zinthu za hydration. HPMC imatha kuletsa kukula kwa nucleation ndi crystal ya ena mwa magawowa, ndikuchepetsanso kutsika kwa simenti.
Pomaliza
Kuphatikizika kwa HPMC kuzinthu za simenti kumatha kuchedwetsa hydration ya simenti, potero kusintha kuchuluka ndi kukula kwa mphamvu. Limagwirira wa kuchedwa simenti hydration makamaka chifukwa mapangidwe chotchinga thupi pakati simenti particles ndi madzi, amene adsorbed pamwamba pa simenti particles ndi linalake ndipo tikulephera nucleation ndi galasi kukula ndondomeko hydration mankhwala. Kumvetsetsa njira zomwe HPMC imalepheretsa simenti kuthira madzi kungatipangitse kukhathamiritsa kugwiritsa ntchito HPMC muzinthu za simenti kuti tipeze zomwe tikufunikira ndikusungabe kukula kwa zida za simenti.
Nthawi yotumiza: Oct-24-2023