1. I-cellulose ether
I-cellulose ether yebanga lokwakha yitemu elivamile lochungechunge lwemikhiqizo elakhiwe ukusabela kwe-alkali cellulose kanye ne-ejenti e-etherifying ngaphansi kwezimo ezithile. I-alkali cellulose ithathelwa indawo ama-etherifying ahlukene ukuze kutholwe ama-cellulose ether ahlukene. Ngokwezakhiwo ze-ionization zama-substituents, ama-cellulose ether angahlukaniswa abe izigaba ezimbili: i-ionic (njenge-carboxymethyl cellulose) kanye ne-non-ionic (njenge-methyl cellulose). Ngokohlobo lwe-substituent, i-cellulose ether ingahlukaniswa ibe yi-mono-ether (efana ne-methyl cellulose) ne-ether exutshiwe (njenge-hydroxypropyl methyl cellulose). Ngokuvumelana ne-solubility ehlukene, ingahlukaniswa ibe inyibilika emanzini (njenge-hydroxyethyl cellulose) kanye ne-organic solvent-soluble (njenge-ethyl cellulose), njll. ihlukaniswe ngohlobo olusheshayo kanye nohlobo lokuchithwa olubambezelekile oluphathwayo.
Indlela yokusebenza ye-cellulose ether odakeni imi kanje:
- Ngemuva kokuthi i-cellulose ether e-mortar ichitheka emanzini, ukusatshalaliswa okusebenzayo nokufana okufanayo kwe-cementitious material ohlelweni kuqinisekiswa ngenxa yomsebenzi ongaphezulu. Njenge-colloid evikelayo, i-cellulose ether “igoqa” izinhlayiya eziqinile futhi izivale endaweni engaphandle. Yakha ifilimu yokugcoba, yenza uhlelo lodaka luzinze, futhi uphinde uthuthukise ukugeleza kodaka ngesikhathi sokuxuba kanye nokushelela kokwakhiwa.
- Ngenxa yesakhiwo sawo samangqamuzana, isixazululo se-cellulose ether senza amanzi odaka angabi lula ukulahlekelwa, futhi kancane kancane akhiphe isikhathi eside, enikeza udaka ngokugcina amanzi kahle nokusebenza.
2. I-methyl cellulose
I-Methylcellulose (MC) ifomula ye-molecular [C6H7O2(OH)3-h(OCH3) n]x.
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.
- 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.
- Ukugcinwa kwamanzi kwe-methylcellulose 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.
- Ukushintsha kwezinga lokushisa kungathinta kakhulu ukugcinwa kwamanzi kwe-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.
- I-Methylcellulose inomthelela omkhulu ekusebenzeni nasekubambeleleni kodaka. Igama elithi “adhesion” lapha libhekisela emandleni okunamathela azwakala phakathi kwethuluzi lokufaka isicelo lesisebenzi kanye ne-substrate yodonga, okungukuthi, ukumelana ne-shear kodaka. I-adhesiveness iphakeme, ukumelana kwe-shear kodaka kukhulu, futhi amandla adingwa ngabasebenzi ngesikhathi sokusebenzisa nawo makhulu, futhi ukusebenza kokwakhiwa kodaka kumpofu. I-Methyl cellulose adhesion isezingeni elilinganiselwe emikhiqizweni ye-cellulose ether.
3.Hydroxypropyl Methyl Cellulose
Ifomula yamangqamuzana ye-hydroxypropyl methylcellulose (HPMC) ithi [C6H7O2(OH)3-mn(OCH3) m, OCH2CH(OH)CH3] n]x
I-Hydroxypropyl methylcellulose iwuhlobo lwe-cellulose okukhipha kanye nokusetshenziswa kwalo kukhuphuka ngokushesha. 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 zihlukile ngenxa yezilinganiso ezihlukene zokuqukethwe kwe-methoxyl nokuqukethwe kwe-hydroxypropyl.
- IHydroxypropyl methylcellulose incibilika kalula emanzini abandayo, kodwa 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.
- 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, i-viscosity yayo ephezulu inomphumela ophansi wokushisa kune-methyl cellulose. Isixazululo saso sizinzile uma sigcinwe ekamelweni lokushisa.
- Ukugcinwa kwamanzi kwe-hydroxypropyl methylcellulose kuncike enanini layo elingeziwe, i-viscosity, njll., futhi izinga layo lokugcinwa kwamanzi ngenani elifanayo lokwengezwa lingaphezulu kwele-methyl cellulose.
- I-Hydroxypropyl methylcellulose izinzile ku-asidi ne-alkali, futhi isixazululo sayo esinamanzi sizinze kakhulu kububanzi be-pH=2~12. I-Caustic soda namanzi e-lime anethonya elincane ekusebenzeni kwawo, kodwa i-alkali ingasheshisa ukuchithwa kwayo futhi ikhulise ukubukeka kwayo. IHydroxypropyl methylcellulose izinzile kusawoti ovamile, kodwa lapho ukuhlangana kwesixazululo sikasawoti kuphezulu, i-viscosity ye-hydroxypropyl methylcellulose solution ivame ukwanda.
- IHydroxypropyl methylcellulose ingaxutshwa nezinhlanganisela ze-polymer ezincibilika emanzini ukuze kwakhiwe isixazululo esifana nese-viscosity esiphezulu. Okufana ne-polyvinyl alcohol, isitashi ether, ushingamu wemifino, njll.
- I-Hydroxypropyl methylcellulose inokumelana ne-enzyme okungcono kune-methylcellulose, futhi isisombululo sayo mancane amathuba okuthi sonakaliswe ama-enzyme kune-methylcellulose.
- Ukunamathela kwe-hydroxypropyl methylcellulose ekwakhiweni kodaka kungaphezulu kwalokho kwe-methyl cellulose.
4.I-Hydroxyethyl cellulose
I-Hydroxyethyl cellulose (HEC)
Yenziwe ngokotini ocolisisiwe ophathwe nge-alkali, futhi isabela nge-ethylene oxide njenge-etherification ejenti lapho kukhona i-acetone. Izinga lokushintsha ngokuvamile liyi-1.5 ~ 2.0. Ine-hydrophilicity eqinile futhi kulula ukumunca umswakama.
- 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.
- I-Hydroxyethyl cellulose izinzile ku-asidi evamile kanye ne-alkali, futhi i-alkali ingasheshisa ukuchithwa kwayo futhi ikhulise kancane i-viscosity yayo. Ukuhlakazeka kwayo emanzini kubi kakhulu kunaleyo ye-methyl cellulose ne-hydroxypropyl methyl cellulose.
- I-Hydroxyethyl cellulose inokusebenza okuhle kwe-anti-sag kudaka, kodwa inesikhathi eside sokubambezeleka kukasimende.
- Ukusebenza kwe-hydroxyethyl cellulose ekhiqizwa amanye amabhizinisi asekhaya ngokusobala kuphansi kunaleyo ye-methyl cellulose ngenxa yamanzi amaningi kanye nomlotha omningi.
5.Carboxymethyl cellulose
I-Carboxymethylcellulose (CMC)[C6H7O2(OH)2OCH2COONA] n
I-ionic cellulose ether yenziwa ngemicu yemvelo (ukotini, njll.) ngemva kokwelashwa kwe-alkali, kusetshenziswa i-sodium mono-chloroacetate njenge-etherification agent, futhi yenza uchungechunge lwemithi yokwelapha. Izinga lokushintsha ngokuvamile lingu-0.4~1.4, futhi ukusebenza kwakho kuthintwa kakhulu izinga lokushintsha.
- I-Carboxymethyl cellulose ine-hygroscopic, futhi izoqukatha amanzi amaningi uma igcinwe ngaphansi kwezimo ezijwayelekile.
- Isixazululo samanzi se-Carboxymethyl cellulose asikhiqizi ijeli, futhi i-viscosity iyancipha ngokunyuka kwezinga lokushisa. Lapho izinga lokushisa lidlula ku-50°C, i-viscosity ayinakubuyela emuva.
- Ukuzinza kwayo kuthinteka kakhulu yi-pH. Ngokuvamile, ingasetshenziswa odakeni olusekelwe ku-gypsum, kodwa hhayi odakeni olusekelwe kusimende. Uma kune-alkaline kakhulu, ilahlekelwa yi-viscosity.
- 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: Mar-30-2023