Ekusetshenzisweni kwei-hydroxypropyl methyl cellulose HPMC, ngokuvamile sithola ukuthi ngokuyisisekelo ihlukaniswe yaba izinhlobo ezimbili: ukuqedwa okusheshayo nokunensayo. Masiqonde umehluko phakathi kokuqedwa okusheshayo nokuqedwa kancane kwe-hydroxypropyl methyl cellulose.
I-HPMC esheshayo ibhekisela ekusetshenzisweni kwe-ejenti exhumanisayo yokwelashwa kwendawo enqubweni yokukhiqiza, ukuze i-HPMC ihlakazeke ngokushesha emanzini abandayo, kodwa hhayi isisombululo sangempela, ngokugqugquzela umfaniswano, i-viscosity ikhuphuka kancane, okungukuthi, ukuchithwa;
I-HPMC encibilika kancane ingaphinde ibizwe ngemikhiqizo encibilikayo eshisayo. Lapho amanzi abandayo ehlangana, angahlakazwa ngokushesha emanzini ashisayo. Ngokugqugquzela ngokulinganayo, izinga lokushisa lesisombululo lizokwehla lifinyelele ekushiseni okuthile. (Izinga lokushisa lejeli yethu lingaba ngu-60 ° C), i-viscosity izovela kancane kuze kube yilapho kwakheka ijeli esobala futhi enamathelayo.
Nawu umehluko phakathi kwesixazululo esisheshayo nesixazululo esinensayo. Uma unemibuzo mayelana nalolu lwazi, ungaphinda usithinte.
I-Hydroxypropyl methyl celluloseI-HPMCukubambezeleka usimende hydration
Ukwengeza i-hydroxypropyl methyl cellulose kusimende kunciphisa ukugeleza kwayo. Wazini-ke ukuthi isebenza kanjani? Ake sibheke i-hydroxypropyl methyl cellulose ukuze kubambezeleke ukugeleza kukasimende. Isimiso.
1. I-ion movement disorder hypothesis
Sacabanga ukuthi i-hydroxypropyl methyl cellulose ingakhuphula i-viscosity yezixazululo ze-pore, ivimbele izinga lokunyakaza kwe-ionic, futhi ibambezele ukugeleza kukasimende. Kodwa-ke, ama-ether e-cellulose e-viscosity aphansi kulokhu kuhlolwa ayenamandla anamandla okubambezela ukugeleza kukasimende. Ngakho-ke, lokhu kucabanga akuvumelekile. Pourchez et al. futhi ungangabazi lo mbono. Eqinisweni, isikhathi sokufuduka kwe-ion noma ukufuduka sifushane kakhulu, ngokusobala asihlukani nokubambezeleka kwe-hydration kasimende.
2. Ukuwohloka kwe-alkaline
Ama-Polysaccharides alulazeka kalula ngaphansi kwezimo ze-alkaline ukuze akhiqize i-hydroxyl carboxylic acids ebambezela ukugeleza kukasimende. Ngakho-ke, ukubambezeleka kwe-hydration ye-hydroxypropyl methyl cellulose kungase kube ngenxa yokuwohloka kwayo kuma-alkaline usimende slurries ukuze yakhe i-hydroxycarboxylic acids. Nokho, uPourchez et al. ithole ukuthi i-cellulose ethers yayizinzile kakhulu ngaphansi kwezimo ze-alkaline, yonakaliswa kancane kuphela, futhi imikhiqizo yokuwohloka yayinomthelela omncane ekubambezelekeni kwe-samente hydration.
3, i-adsorption
I-Adsorption ingaba i-hydroxypropyl methyl cellulose block usimende hydration isizathu sangempela ukuthi izithasiselo eziningi eziphilayo zizokhangiswa ezinhlayiyeni zikasimende nemikhiqizo ye-hydration, kuvimbele ukuhlakazeka kwezinhlayiya zikasimende kanye ne-crystallization yemikhiqizo ye-hydration, ukuze kubambezeleke ukugeleza nokufiphala kukasimende. Pourchez et al. ithole ukuthi ama-cellulose ethers akhangeka kalula ezindaweni zemikhiqizo ye-hydroxide efana ne-calcium hydroxide, ijeli ye-CSH ne-calcium aluminate hydrate, kodwa engakhangiswa kalula ngezigaba ze-ettringite ne-unhydrated. Ngaphezu kwalokho, esimweni se-cellulose ether, umthamo we-adsorption we-HEC unamandla kunalowo wokuvuvukala kwe-MC. Ukwehlisa okuqukethwe kwe-hydroxyethyl ku-HEC noma ku-hydroxypropyl inI-HPMC, amandla e-adsorption anamandla: ngokuqondene nemikhiqizo ye-hydration, umthamo we-adsorption we-calcium hydroxide unamandla kunawe-CSH. Ukuhlaziywa okwengeziwe futhi kubonisa ukuthi umthamo we-adsorption wemikhiqizo ye-hydration kanye ne-cellulose ether ihlobene nokubambezeleka kwe-cement hydration: ukuqina kwe-adsorption, ukubambezeleka okusobala kakhulu, kodwa i-ettringite adsorption ye-cellulose ether ibuthakathaka, kodwa ukwakheka kwayo, kodwa lokhu kubambezeleka kakhulu. I-cellulose ether ye-tricalcium silicate kanye nemikhiqizo yayo ye-hydration ine-adsorption eqinile, ngokusobala ibambezela inqubo ye-hydration yesigaba se-silicate, inani le-adsorption ye-ettringite liphansi kakhulu, kodwa ukwakheka kwe-ettringite okubambezelekile kubonakala, ngenxa yokubambezeleka kokwakheka kwe-ettringite kuthinteka yi-Ca 2 + ibhalansi kusixazululo, isandiso se-cellulose ether. I-silicate hydration ephuzile iqhubekile.
Lawa umgomo we-hydroxypropyl methyl cellulose ukubambezeleka kukasimende we-hydration. Sithemba ukuthi lolu lwazi luzokwenza wonke umuntu aqonde ukuthi umkhiqizo usebenza kanjani futhi awusebenzise kangcono.
Isikhathi sokuthumela: Apr-26-2024