I-Cellulose ether yitemu elivamile lochungechunge lwemikhiqizo ekhiqizwa ukusabela kwe-alkali cellulose kanye ne-etherifying agent ngaphansi kwezimo ezithile. I-alkali cellulose ithathelwa indawo ama-etherifying ahlukene ukuze kutholwe ama-cellulose ether ahlukene. Ngokuya ngezici ze-ionization zama-substituents, ama-cellulose ether angahlukaniswa abe izigaba ezimbili: i-ionic (njenge-carboxymethyl cellulose) kanye ne-nonionic (njenge-methyl cellulose). Ngokohlobo lwe-substituent, i-cellulose ether ingahlukaniswa ibe i-monoether (efana ne-methyl cellulose) ne-ether exutshiwe (njenge-hydroxypropyl methyl cellulose). Ngokuvumelana ne-solubility ehlukene, ingahlukaniswa ibe ukunyibilika kwamanzi (okufana ne-hydroxyethyl cellulose) kanye ne-organic solvent solubility (njenge-ethyl cellulose). Udaka oluxutshwe okomile ngokuyinhloko luyi-cellulose encibilika emanzini, futhi i-cellulose encibilika emanzini ihlukaniswe yaba uhlobo olusheshayo kanye nohlobo lokulibaziseka lokuncibilika olulashwe phezulu.
Indlela yokusebenza ye-cellulose ether odakeni imi kanje:
(1) Ngemva kokuba i-cellulose ether esesimendeni isincibilikisiwe emanzini, ukusatshalaliswa okusebenzayo nokufana kwe-cementitious material ohlelweni kuyaqinisekiswa ngenxa yomsebenzi ongaphezulu, futhi i-cellulose ether, njenge-colloid evikelayo, "igoqa" okuqinile. izinhlayiya kanye Ungqimba lwefilimu yokugcoba kwakheka endaweni yalo yangaphandle, okwenza uhlelo lodaka luzinze, futhi luthuthukise ukugeleza kodaka ngesikhathi sokuxuba kanye nokushelela kokwakhiwa.
(2) Ngenxa yezici zayo zesakhiwo samangqamuzana, isixazululo se-cellulose ether senza umswakama osesimendeni ungabi lula ukulahlekelwa, futhi kancane kancane uyawukhulula isikhathi eside, unikeze udaka ngokugcina amanzi kahle nokusebenza.
1. I-methylcellulose: (MC)
Ngemuva kokuthi ukotini ocolisisiwe ulashwe nge-alkali, i-cellulose ether ikhiqizwa ngochungechunge lokusabela nge-methane chloride njenge-etherification agent. Ngokuvamile, izinga lokushintsha lingu-1.6~2.0, futhi ukunyibilika nakho kuhlukile ngamazinga ahlukene okushintsha. Kungokwe-non-ionic cellulose ether.
(1) I-methylcellulose iyancibilika emanzini abandayo, futhi kuyoba nzima ukuyincibilika emanzini ashisayo. Isixazululo saso esinamanzi sizinzile kakhulu ebangeni le-pH=3~12. Inokuhambisana okuhle nesitashi, i-guar gum, njll kanye nama-surfactants amaningi. Lapho izinga lokushisa lifinyelela izinga lokushisa le-gelation, i-gelation iyenzeka.
(2) Ukugcinwa kwamanzi kwe-methyl cellulose kuncike enanini layo elingeziwe, i-viscosity, ukucoleka kwezinhlayiyana nezinga lokuqedwa. Ngokuvamile, uma inani elingeziwe likhulu, ukucoleka kuncane, futhi i-viscosity inkulu, izinga lokugcinwa kwamanzi liphezulu. Phakathi kwazo, inani lokwengeza linomthelela omkhulu kakhulu ekugcinweni kwamanzi, futhi izinga le-viscosity alilingani ngokuqondile nezinga lokugcinwa kwamanzi. Izinga lokuhlakazeka lincike kakhulu ezingeni lokuguqulwa kwendawo yezinhlayiya ze-cellulose kanye nokucoleka kwezinhlayiyana. Phakathi kwama-cellulose ether angenhla, i-methyl cellulose ne-hydroxypropyl methyl cellulose anamazinga aphezulu okugcina amanzi.
(3) Ukushintsha kwezinga lokushisa kuzothinta kakhulu izinga lokugcinwa kwamanzi e-methyl cellulose. Ngokuvamile, lapho izinga lokushisa liphezulu, kuba kubi nakakhulu ukugcinwa kwamanzi. Uma izinga lokushisa lodaka lidlula i-40 ° C, ukugcinwa kwamanzi kwe-methyl cellulose kuzoncishiswa kakhulu, okuthinta kakhulu ukwakhiwa kodaka.
(4) I-Methyl cellulose inomphumela ophawulekayo ekwakhiweni nasekuhlanganisweni kodaka. “Ukunamathela” lapha kubhekisela kumandla okubopha azwakala phakathi kwethuluzi lesisebenzi lesifakeli kanye nengxenye yodonga, okungukuthi, ukumelana nokugunda kodaka. I-adhesiveness iphakeme, ukumelana kwe-shear kodaka kukhulu, futhi amandla adingwa ngabasebenzi ngesikhathi sokusebenzisa nawo makhulu, futhi ukusebenza kokwakhiwa kodaka kumpofu. Ukuhlangana kwe-methyl cellulose kusezingeni eliphakathi emikhiqizweni ye-cellulose ether.
2. I-Hydroxypropyl methyl cellulose (HPMC):
IHydroxypropyl methylcellulose iwuhlobo lwe-cellulose okukhishwa kwayo nokusetshenziswa kwayo kukhule ngokushesha eminyakeni yamuva. I-ether engeyona i-ionic cellulose exutshwe ukotini ocolisisiwe ngemva kokwenziwa kwe-alkalization, kusetshenziswa i-propylene oxide ne-methyl chloride njenge-etherification agent, ngochungechunge lokusabela. Izinga lokushintsha ngokuvamile liyi-1.2 ~ 2.0. Izakhiwo zayo ziyahlukahluka kuye ngesilinganiso sokuqukethwe kwe-methoxyl kokuqukethwe kwe-hydroxypropyl.
(1) IHydroxypropyl methylcellulose incibilika kalula emanzini abandayo, futhi izohlangabezana nobunzima ekuncibilikeni emanzini ashisayo. Kodwa izinga lokushisa layo le-gelation emanzini ashisayo liphakeme kakhulu kunalelo le-methyl cellulose. I-solubility emanzini abandayo nayo ithuthuke kakhulu uma iqhathaniswa ne-methyl cellulose.
(2) I-viscosity ye-hydroxypropyl methylcellulose ihlobene nesisindo sayo samangqamuzana, futhi uma sikhulu isisindo samangqamuzana, i-viscosity iphakama. Ukushisa nakho kuthinta i-viscosity yayo, njengoba izinga lokushisa likhuphuka, i-viscosity iyancipha. Kodwa-ke, ithonya le-viscosity yayo ephezulu kanye nezinga lokushisa liphansi kunalelo le-methyl cellulose. Isixazululo saso sizinzile uma sigcinwe ekamelweni lokushisa.
(3) Ukugcinwa kwamanzi kwe-hydroxypropyl methylcellulose kuncike enanini layo elingeziwe, i-viscosity, njll., futhi izinga layo lokugcinwa kwamanzi ngaphansi kwenani elifanayo lokwengezwa lingaphezulu kwele-methyl cellulose.
(4) I-Hydroxypropyl methylcellulose izinzile ku-asidi ne-alkali, futhi isisombululo sayo esinamanzi sizinzile kakhulu ebangeni le-pH = 2 ~ 12. I-Caustic soda namanzi e-lime anethonya elincane ekusebenzeni kwawo, kodwa i-alkali ingasheshisa ukuchithwa kwayo futhi ikhulise kancane i-viscosity yayo. IHydroxypropyl methylcellulose izinzile kusawoti ovamile, kodwa lapho ukuhlangana kwesixazululo sikasawoti kuphezulu, i-viscosity ye-hydroxypropyl methylcellulose solution ivame ukwanda.
(5) I-Hydroxypropyl methylcellulose ingaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini ukuze zenze isixazululo se-uniform kanye ne-viscosity ephakeme. Okufana ne-polyvinyl alcohol, isitashi ether, ushingamu wemifino, njll.
(6) I-Hydroxypropyl methylcellulose inokumelana ne-enzyme engcono kune-methylcellulose, futhi kungenzeka ukuwohloka kwe-enzymatic yesisombululo sayo kungaphansi kwe-methylcellulose.
(7) Ukunamathela kwe-hydroxypropyl methylcellulose ekwakhiweni kodaka kungaphezulu kwalokho kwe-methylcellulose.
3. I-Hydroxyethyl cellulose (HEC):
Yenziwe ngokotini ocolisisiwe ophathwe nge-alkali, futhi isabela nge-ethylene oxide njenge-etherification ejenti lapho kukhona i-acetone. Izinga layo lokushintsha ngokuvamile liyi-1.5 ~ 2.0. Ine-hydrophilicity eqinile futhi kulula ukumunca umswakama.
(1) I-Hydroxyethyl cellulose iyancibilika emanzini abandayo, kodwa kunzima ukuyincibilika emanzini ashisayo. Isixazululo saso sizinzile ekushiseni okuphezulu ngaphandle kwe-gelling. Ingasetshenziswa isikhathi eside ngaphansi kokushisa okuphezulu odakeni, kodwa ukugcinwa kwayo kwamanzi kuphansi kunaleyo ye-methyl cellulose.
(2) I-Hydroxyethyl cellulose izinzile ku-asidi evamile kanye ne-alkali. I-alkali ingasheshisa ukuqedwa kwayo futhi ikhulise kancane i-viscosity yayo. Ukuhlakazeka kwayo emanzini kubi kakhulu kunaleyo ye-methyl cellulose ne-hydroxypropyl methyl cellulose. .
(3) I-Hydroxyethyl cellulose inokusebenza okuhle kwe-anti-sag kudaka, kodwa inesikhathi eside sokuhlehlisa usimende.
(4) Ukusebenza kwe-hydroxyethyl cellulose ekhiqizwa amanye amabhizinisi asekhaya kuphansi kakhulu kunaleyo ye-methyl cellulose ngenxa yokuqukethwe kwayo kwamanzi amaningi kanye nomlotha omningi.
4. I-Carboxymethyl cellulose (CMC):
I-ionic cellulose ether yenziwa ngemicu yemvelo (ukotini, njll.) ngemva kokwelashwa kwe-alkali, kusetshenziswa i-sodium monochloroacetate njenge-etherification agent, futhi kwenziwa uchungechunge lwemithi yokwelapha. Izinga lokushintsha ngokuvamile lingu-0.4~1.4, futhi ukusebenza kwakho kuthintwa kakhulu izinga lokushintsha.
(1) I-Carboxymethyl cellulose ine-hygroscopic, futhi izoqukatha amanzi amaningi uma igcinwe ngaphansi kwezimo ezijwayelekile.
(2) Isixazululo samanzi se-Carboxymethyl cellulose ngeke sikhiqize ijeli, futhi i-viscosity izokwehla ngokunyuka kwezinga lokushisa. Lapho izinga lokushisa lidlula ku-50°C, i-viscosity ayinakubuyela emuva.
(3) Ukuzinza kwayo kuthinteka kakhulu yi-PH. Ngokuvamile, ingasetshenziswa odakeni olusekelwe ku-gypsum, kodwa hhayi odakeni olusekelwe kusimende. Uma kune-alkaline kakhulu, izolahlekelwa yi-viscosity.
(4) Ukugcinwa kwayo kwamanzi kuphansi kakhulu kunaleyo ye-methyl cellulose. Inomphumela wokuhlehlisa odakeni olususelwa ku-gypsum futhi inciphisa amandla ayo. Nokho, intengo ye-carboxymethyl cellulose iphansi kakhulu kunaleyo ye-methyl cellulose.
Isikhathi sokuthumela: Feb-27-2023