Ma cellulose ether ndi liwu lodziwika bwino lazinthu zingapo zopangidwa ndi momwe alkali cellulose ndi etherifying agent pansi pazifukwa zina. Ma cellulose a alkali amasinthidwa ndi ma etherifying othandizira kuti apeze ma cellulose ethers osiyanasiyana. Malinga ndi ma ionization a zinthu zolowa m'malo, ma cellulose ether amatha kugawidwa m'magulu awiri: ionic (monga carboxymethyl cellulose) ndi nonionic (monga methyl cellulose). Malinga ndi mtundu wa zolowa m'malo, cellulose ether imatha kugawidwa kukhala monoether (monga methyl cellulose) ndi ether yosakanikirana (monga hydroxypropyl methyl cellulose). Malinga ndi kusungunuka kosiyanasiyana, imatha kugawidwa m'madzi (monga hydroxyethyl cellulose) ndi organic solvent solubility (monga ethyl cellulose). Mtondo wosakanizika wowuma umakhala makamaka wosungunuka m'madzi, ndipo cellulose yosungunuka m'madzi imagawidwa kukhala mtundu wanthawi yomweyo komanso mtundu wothiridwa pamwamba wochedwa-kusungunuka.
Limagwirira ntchito ya cellulose ether mu matope ndi motere:
(1) Pambuyo pa etha ya cellulose mumatope itasungunuka m'madzi, kugawa kogwira mtima ndi kofanana kwa zinthu za simenti m'dongosolo kumatsimikiziridwa chifukwa cha ntchito yapamtunda, ndipo cellulose ether, monga colloid yoteteza, "kukulunga" cholimba. particles ndi A wosanjikiza lubricating filimu aumbike pamwamba pake, zomwe zimapangitsa matope dongosolo khola, komanso bwino fluidity wa matope pa ndondomeko kusanganikirana ndi kusalala kwa zomangamanga.
(2) Chifukwa cha mawonekedwe ake a mamolekyu, njira ya cellulose ether imapangitsa kuti chinyezi mumtondo chisawonongeke, ndipo pang'onopang'ono chimachimasula kwa nthawi yayitali, ndikupangitsa kuti matope azikhala ndi madzi osungira bwino komanso ogwira ntchito.
1. Methylcellulose: (MC)
Thonje woyengedwa akagwiritsidwa ntchito ndi alkali, cellulose ether imapangidwa kudzera muzochita zingapo ndi methane chloride ngati etherification agent. Nthawi zambiri, kuchuluka kwa m'malo ndi 1.6 ~ 2.0, ndipo kusungunuka kwake kumasiyananso ndi magawo osiyanasiyana olowa m'malo. Ndi ya non-ionic cellulose ether.
(1) Methylcellulose imasungunuka m'madzi ozizira, ndipo zimakhala zovuta kusungunuka m'madzi otentha. Njira yake yamadzimadzi imakhala yokhazikika pa pH = 3 ~ 12. Iwo ali ngakhale bwino ndi wowuma, guar chingamu, etc. ndi surfactants ambiri. Pamene kutentha kufika kutentha kwa gelation, gelation imachitika.
(2) Kusungidwa kwa madzi kwa methyl cellulose kumadalira kuchuluka kwake, kukhuthala, kukongola kwa tinthu ndi kusungunuka kwake. Nthawi zambiri, ngati kuchuluka kwake kuli kwakukulu, fineness ndi yaying'ono, ndipo mamasukidwe ake ndiakuluakulu, kuchuluka kwa kusunga madzi kumakhala kwakukulu. Pakati pawo, kuchuluka kwa kuwonjezera kumakhudza kwambiri kuchuluka kwa kusungirako madzi, ndipo msinkhu wa viscosity suli wofanana mwachindunji ndi mlingo wa kusunga madzi. The Kusungunuka mlingo makamaka zimadalira mlingo wa padziko kusinthidwa kwa mapadi particles ndi tinthu fineness. Pakati pa ma cellulose ethers omwe ali pamwambawa, methyl cellulose ndi hydroxypropyl methyl cellulose ali ndi milingo yayikulu yosungira madzi.
(3) Kusintha kwa kutentha kudzakhudza kwambiri kuchuluka kwa madzi osungira madzi a methyl cellulose. Nthawi zambiri, kutentha kumapangitsa kuti madzi asamasungidwe kwambiri. Ngati kutentha kwa matope kupitirira 40 ° C, kusungirako madzi kwa methyl cellulose kudzachepetsedwa kwambiri, zomwe zimakhudza kwambiri kupanga matope.
(4) Methyl cellulose imakhudza kwambiri kumanga ndi kugwirizanitsa matope. “Kumamatira” pano kukutanthauza mphamvu yomangirira yomwe imamveka pakati pa chida cha wogwiritsa ntchito ndi gawo lapansi la khoma, ndiko kuti, kukana kukameta ubweya wa matope. Kumamatira kumakhala kwakukulu, kukana kukameta ubweya wa matope ndi kwakukulu, ndipo mphamvu zomwe ogwira ntchito amafunikira pakugwiritsa ntchito zimakhala zazikulu, ndipo ntchito yomanga matope ndi yosauka. Kugwirizana kwa methyl cellulose kuli pamlingo wapakatikati muzinthu za cellulose ether.
2. Hydroxypropyl methyl cellulose (HPMC):
Hydroxypropyl methylcellulose ndi mitundu ya cellulose yomwe kutulutsa kwake ndikugwiritsa ntchito kwakhala kukuchulukirachulukira m'zaka zaposachedwa. Ndi cellulose yopanda ionic yosakaniza ether yopangidwa kuchokera ku thonje woyengedwa pambuyo pa alkalization, pogwiritsa ntchito propylene oxide ndi methyl chloride monga etherification agent, kupyolera muzotsatira zingapo. Mlingo wolowa m'malo nthawi zambiri ndi 1.2 ~ 2.0. Katundu wake amasiyana malinga ndi kuchuluka kwa methoxyl zomwe zili ndi hydroxypropyl.
(1) Hydroxypropyl methylcellulose imasungunuka mosavuta m'madzi ozizira, ndipo imakumana ndi zovuta pakusungunuka m'madzi otentha. Koma kutentha kwake kwa gelation m'madzi otentha ndikokwera kwambiri kuposa kwa methyl cellulose. Kusungunuka m'madzi ozizira kumakhalanso bwino kwambiri poyerekeza ndi methyl cellulose.
(2) Kukhuthala kwa hydroxypropyl methylcellulose kumakhudzana ndi kulemera kwake kwa mamolekyulu, ndipo kukula kwake kwa molekyulu kumapangitsa kukhuthala kwamphamvu. Kutentha kumakhudzanso kukhuthala kwake, pamene kutentha kumawonjezeka, kukhuthala kumachepa. Komabe, chikoka cha mamasukidwe ake apamwamba komanso kutentha kwake kumakhala kotsika kuposa kwa methyl cellulose. Yankho lake ndi lokhazikika likasungidwa kutentha.
(3) Kusungidwa kwa madzi kwa hydroxypropyl methylcellulose kumadalira kuchuluka kwake, kukhuthala kwake, ndi zina zambiri, ndipo kuchuluka kwake komwe kumasungira madzi pansi pa kuchuluka komweko ndikokwera kuposa kwa methyl cellulose.
(4) Hydroxypropyl methylcellulose ndi yokhazikika ku asidi ndi alkali, ndipo njira yake yamadzimadzi imakhala yokhazikika pa pH = 2 ~ 12. Madzi a caustic ndi laimu sakhala ndi zotsatira zochepa pa ntchito yake, koma alkali amatha kufulumizitsa kusungunuka kwake ndikuwonjezera kukhuthala kwake pang'ono. Hydroxypropyl methylcellulose ndi yokhazikika ku mchere wamba, koma pamene mchere wa mchere uli wambiri, kukhuthala kwa hydroxypropyl methylcellulose solution kumawonjezeka.
(5) Hydroxypropyl methylcellulose akhoza kusakaniza ndi madzi sungunuka polima mankhwala kupanga yunifolomu ndi apamwamba mamasukidwe akayendedwe njira. Monga polyvinyl mowa, wowuma ether, masamba chingamu, etc.
(6) Hydroxypropyl methylcellulose imakhala ndi kukana bwino kwa enzyme kuposa methylcellulose, ndipo kuthekera kwa kuwonongeka kwa enzymatic kwa yankho lake ndikotsika kuposa methylcellulose.
(7) Kumamatira kwa hydroxypropyl methylcellulose kumapangidwe amatope ndikokwera kuposa methylcellulose.
3. Hydroxyethyl cellulose (HEC):
Amapangidwa kuchokera ku thonje loyengedwa lopangidwa ndi alkali, ndipo amachita ndi ethylene oxide ngati etherification agent pamaso pa acetone. Mlingo wake wolowa m'malo nthawi zambiri ndi 1.5 ~ 2.0. Ili ndi hydrophilicity yamphamvu ndipo ndiyosavuta kuyamwa chinyezi.
(1) Hydroxyethyl cellulose imasungunuka m'madzi ozizira, koma ndizovuta kusungunuka m'madzi otentha. Yankho lake ndi khola pa kutentha popanda gelling. Ikhoza kugwiritsidwa ntchito kwa nthawi yaitali pansi pa kutentha kwakukulu mumatope, koma kusungirako madzi kumakhala kochepa kusiyana ndi methyl cellulose.
(2) Ma cellulose a Hydroxyethyl ndi okhazikika ku acid ndi zamchere. Alkali imatha kufulumizitsa kusungunuka kwake ndikuwonjezera kukhuthala kwake pang'ono. Kuwonongeka kwake m'madzi kumakhala koyipa pang'ono kuposa methyl cellulose ndi hydroxypropyl methyl cellulose. .
(3) Ma cellulose a Hydroxyethyl ali ndi ntchito yabwino yotsutsa-sag pamatope, koma amakhala ndi nthawi yayitali yochepetsera simenti.
(4) Magwiridwe a hydroxyethyl cellulose opangidwa ndi mabizinesi ena apakhomo ndi otsika kwambiri kuposa a methyl cellulose chifukwa chokhala ndi madzi ochulukirapo komanso phulusa lalitali.
4. Carboxymethyl cellulose (CMC):
Ionic cellulose ether imapangidwa kuchokera ku ulusi wachilengedwe (thonje, etc.) pambuyo pa mankhwala a alkali, pogwiritsa ntchito sodium monochloroacetate monga etherification wothandizira, ndikulandira chithandizo chamankhwala angapo. Mlingo wolowa m'malo nthawi zambiri ndi 0.4 ~ 1.4, ndipo magwiridwe ake amakhudzidwa kwambiri ndi kuchuluka kwa m'malo.
(1) Carboxymethyl cellulose imakhala ndi hygroscopic, ndipo imakhala ndi madzi ambiri ikasungidwa nthawi zambiri.
(2) Carboxymethyl cellulose amadzimadzi njira sipanga gel osakaniza, ndipo mamasukidwe akayendedwe adzachepa ndi kuwonjezeka kutentha. Kutentha kupitilira 50 ° C, kukhuthala kwake sikungasinthe.
(3) Kukhazikika kwake kumakhudzidwa kwambiri ndi PH. Nthawi zambiri, itha kugwiritsidwa ntchito mumatope opangidwa ndi gypsum, koma osati mumatope opangidwa ndi simenti. Pamene kwambiri zamchere, izo kutaya mamasukidwe akayendedwe.
(4) Kusunga madzi ake ndikotsika kwambiri kuposa methyl cellulose. Imalepheretsa matope a gypsum ndipo imachepetsa mphamvu zake. Komabe, mtengo wa carboxymethyl cellulose ndi wotsika kwambiri kuposa wa methyl cellulose.
Nthawi yotumiza: Feb-27-2023