Magulu a hydroxyl paether ya celluloseMamolekyulu ndi maatomu a okosijeni omwe ali pa ma ether bonds amapanga ma hydrogen bonds ndi mamolekyulu amadzi, zomwe zimapangitsa kuti madzi aulere akhale madzi omangika, motero zimathandiza kwambiri pakusunga madzi; kufalikira pakati pa mamolekyulu amadzi ndi ma cellulose ether molecular chains kumalola mamolekyulu amadzi kulowa mkati mwa cellulose ether macromolecular chain ndikukhala ndi zoletsa zamphamvu, motero amapanga madzi aulere ndi madzi omangika, zomwe zimapangitsa kuti simenti isamasunge madzi; cellulose ether imakonza rheological properties, porous network structure ndi osmotic pressure ya simenti yatsopano kapena film-forming properties ya cellulose ether imalepheretsa kufalikira kwa madzi.
Kusunga madzi kwa cellulose ether kumachokera ku kusungunuka ndi kuchepa kwa madzi m'thupi kwa cellulose ether yokha. Mphamvu ya hydration ya magulu a hydroxyl yokha sikokwanira kulipira ma hydrogen bond amphamvu ndi mphamvu za van der Waals pakati pa mamolekyulu, kotero imangotupa koma siisungunuka m'madzi. Pamene ma substituents alowetsedwa mu unyolo wa mamolekyulu, ma substituents samangowononga ma hydrogen chains, komanso ma interchain hydrogen bonds amawonongeka chifukwa cha kugawanika kwa ma substituents pakati pa ma chains oyandikana nawo. Ma substituents akakula, mtunda pakati pa mamolekyulu umakula, ndipo zotsatira za kuwononga ma hydrogen bonds zimakula. Cellulose lattice ikatupa, yankho limalowa, ndipo cellulose ether imasungunuka m'madzi, ndikupanga yankho la high-viscosity, lomwe limagwira ntchito posunga madzi.
Zinthu zomwe zimakhudza momwe madzi amasungidwira:
Kukhuthala: Kukhuthala kwa etha ya cellulose, kumakhala bwino kusunga madzi, koma kukhuthala kwakukulu, kulemera kwa maselo a etha ya cellulose kumakwera, ndipo kusungunuka kwake kumachepa moyenerera, zomwe zimakhudza kwambiri kuchuluka kwa matope ndi kapangidwe kake. Kawirikawiri, pa chinthu chomwecho, zotsatira za kukhuthala zomwe zimayesedwa ndi njira zosiyanasiyana zimakhala zosiyana kwambiri, kotero poyerekeza kukhuthala, ziyenera kuchitika pakati pa njira zomwezo zoyesera (kuphatikizapo kutentha, rotor, ndi zina zotero).
Kuchuluka kwa ether yowonjezera: Kuchuluka kwa ether ya cellulose yowonjezeredwa ku matope, kumakhala bwino kwambiri pakusunga madzi. Nthawi zambiri, ether yochepa ya cellulose imatha kusintha kwambiri kuchuluka kwa madzi omwe amasungidwa mumatope. Kuchulukako kukafika pamlingo winawake, chizolowezi chowonjezera kuchuluka kwa madzi omwe amasungidwa chimachepa.
Kusalala kwa tinthu tating'onoting'ono: Tinthu tating'onoting'ono tikakhala tating'onoting'ono, timasunga bwino madzi. Tinthu tating'onoting'ono ta cellulose ether tikakumana ndi madzi, pamwamba pake timasungunuka nthawi yomweyo ndikupanga gel yokulunga zinthuzo kuti mamolekyu amadzi asapitirire kulowa. Nthawi zina, ngakhale kusakaniza kwa nthawi yayitali sikungathe kufalikira ndi kusungunuka kofanana, ndikupanga yankho lozungulira kapena agglomeration, zomwe zimakhudza kwambiri kusunga madzi kwa cellulose ether. Kusungunuka ndi chimodzi mwazinthu zomwe zimasankhidwira cellulose ether. Kusalala ndi chizindikiro chofunikira cha magwiridwe antchito a methyl cellulose ether. Kusalala kumakhudza kusungunuka kwa methyl cellulose ether. Coarser MC nthawi zambiri imakhala ndi granular ndipo imatha kusungunuka mosavuta m'madzi popanda agglomeration, koma kuchuluka kwa kusungunuka kumakhala kochedwa kwambiri ndipo sikoyenera kugwiritsidwa ntchito mu matope ouma.
Kutentha: Pamene kutentha kwa mlengalenga kukukwera, kusunga madzi kwa ma cellulose ethers nthawi zambiri kumachepa, koma ma cellulose ether ena osinthidwa amakhala ndi kusunga bwino madzi pansi pa kutentha kwakukulu; kutentha kukakwera, madzi a ma polima amachepa, ndipo madzi pakati pa maunyolo amatuluka. Madzi akachepa mokwanira, mamolekyu amayamba kusonkhana kuti apange gel yomangidwa ndi maukonde atatu.
Kapangidwe ka mamolekyu: Ma ether a cellulose omwe ali ndi malo ochepa osinthira amakhala ndi madzi abwino osungira.
Kukhuthala ndi thixotropy
Kukhuthala:
Zotsatira pa mphamvu yolumikizirana ndi magwiridwe antchito oletsa kugwedezeka: Ma cellulose ethers amapatsa matope onyowa kukhuthala kwabwino, komwe kumatha kuwonjezera kwambiri mphamvu yolumikizirana ya matope onyowa ndi gawo loyambira ndikuwonjezera magwiridwe antchito oletsa kugwedezeka kwa matope. Amagwiritsidwa ntchito kwambiri popaka matope, matope olumikizira matailosi ndi makina oteteza makoma akunja 3.
Zotsatira pa kufanana kwa zinthu: Kukhuthala kwa ma cellulose ethers kungathandizenso kuletsa kufalikira ndi kufanana kwa zinthu zatsopano zosakanikirana, kuletsa kugawikana kwa zinthu, kulekanitsa ndi kutuluka kwa madzi, ndipo kungagwiritsidwe ntchito mu konkriti ya ulusi, konkriti ya pansi pa madzi ndi konkriti yodzikakamiza yokha.
Magwero ndi mphamvu ya kukhuthala: Kukhuthala kwa etha ya cellulose pa zinthu zopangidwa ndi simenti kumachokera ku kukhuthala kwa yankho la etha ya cellulose. Pansi pa mikhalidwe yomweyi, kukhuthala kwa etha ya cellulose kumakhala kwakukulu, kukhuthala kwa zinthu zopangidwa ndi simenti yosinthidwa kumakhala bwino, koma ngati kukhuthala kuli kwakukulu kwambiri, kudzakhudza kusinthasintha ndi kugwira ntchito kwa zinthuzo (monga kumamatira ku mpeni wopaka pulasitala). Mtondo wodziyimira pawokha ndi konkire wodzigwirizanitsa wofunikira kwambiri kufunikira kukhuthala kochepa kwambiri kwa etha ya cellulose. Kuphatikiza apo, kukhuthala kwa etha ya cellulose kudzawonjezeranso kufunikira kwa madzi kwa zinthu zopangidwa ndi simenti ndikuwonjezera kutulutsa kwa matope.
Thixotropy:
Madzi a cellulose ether okhala ndi kukhuthala kwakukulu ali ndi thixotropy yambiri, yomwe ndi khalidwe lalikulu la cellulose ether. Madzi a methyl cellulose nthawi zambiri amakhala ndi pseudoplasticity komanso non-thixotropic fluidity pansi pa kutentha kwa gel, koma amawonetsa mphamvu za Newtonian flow pamlingo wotsika wa shear. Pseudoplasticity imawonjezeka ndi kuwonjezeka kwa kulemera kwa cellulose ether molecular weight kapena concentration, ndipo sikukhudzana ndi mtundu wa substituent ndi digiri ya substitution. Chifukwa chake, cellulose ethers ya kalasi yofanana ya viscosity, kaya MC, HPMC, kapena HEMC, nthawi zonse amawonetsa mphamvu zofanana za rheological bola ngati concentration ndi kutentha zimakhalabe chimodzimodzi. Kutentha kukakwera, structural gel imapangidwa, ndipo kuyenda kwa thixotropic kwakukulu kumachitika. Cellulose ethers yokhala ndi concentration yayikulu komanso viscosity yochepa imawonetsa thixotropy ngakhale pansi pa kutentha kwa gel. Properties izi ndizothandiza kwambiri posintha kuleza ndi kutsika kwa stima yomanga panthawi yomanga.
Kulowetsa mpweya
Mfundo ndi zotsatira zake pa magwiridwe antchito: Cellulose ether imakhala ndi mphamvu yayikulu yolowetsa mpweya pazinthu zatsopano zopangidwa ndi simenti. Cellulose ether ili ndi magulu okonda madzi (magulu a hydroxyl, magulu a ether) ndi magulu okonda madzi (magulu a methyl, mphete za glucose). Ndi chinthu chopangira madzi chomwe chimagwira ntchito pamwamba, motero chimakhala ndi mphamvu yolowetsa mpweya. Mphamvu yolowetsa mpweya imapanga mphamvu, zomwe zingathandize kuti zinthu zatsopano zigwire bwino ntchito, monga kuwonjezera pulasitiki ndi kusalala kwa matope panthawi yogwira ntchito, zomwe zimathandiza kufalitsa matope; zidzawonjezeranso kutulutsa kwa matope ndikuchepetsa mtengo wopanga matope.
Zotsatira pa makhalidwe a makina: Mphamvu ya mpweya wolowera idzawonjezera ma porosity a chinthu cholimba ndikuchepetsa mphamvu zake monga mphamvu ndi elastic modulus.
Zotsatira pa kusinthasintha kwa madzi: Monga chinthu chopangira madzi, cellulose ether imakhalanso ndi mphamvu yonyowetsa kapena kudzola pa tinthu ta simenti, zomwe pamodzi ndi mphamvu yake yolowetsa mpweya zimawonjezera kusinthasintha kwa zinthu zopangidwa ndi simenti, koma mphamvu yake yokulitsa imachepetsa kusinthasintha kwa madzi. Zotsatira za cellulose ether pa kusinthasintha kwa zinthu zopangidwa ndi simenti ndi kuphatikiza kwa pulasitiki ndi kukhuthala. Nthawi zambiri, pamene mlingo wa cellulose ether uli wochepa kwambiri, umawonekera makamaka ngati pulasitiki kapena kuchepetsa madzi; pamene mlingo uli wokwera, mphamvu ya cellulose ether imawonjezeka mofulumira, ndipo mphamvu yake yolowetsa mpweya imakhala yodzaza, kotero imawonekera ngati kukhuthala kapena kuwonjezeka kwa kufunikira kwa madzi.
Nthawi yotumizira: Disembala-23-2024