I-MC yi-methyl cellulose, efumaneka ngokuphatha i-cotton esulungekileyo nge-alkali, isebenzisa i-methyl chloride njenge-etherifying agent, kunye nokwenza i-cellulose ether ngokusebenzisa uluhlu lweempendulo. Ngokubanzi, iqondo lokutshintsha liyi-1.6 ~ 2.0, kwaye ukunyibilika kwahluka ngokwamanqanaba okutshintsha. yeye-non-ionic cellulose ether.
(1) Ugcino lwamanzii-methyl cellulosekuxhomekeke kwisixa sokongeza, i-viscosity, i-particle fineness kunye nesantya sokuchithwa. Ngokuqhelekileyo, ukuba inani lokongezwa likhulu, ukulunga kuncinci, kwaye i-viscosity inkulu, izinga lokugcinwa kwamanzi liphezulu. Phakathi kwabo, inani lokongezwa linempembelelo enkulu kwizinga lokugcinwa kwamanzi, kwaye inqanaba le-viscosity alilingani nenqanaba lokugcinwa kwamanzi. Izinga lokutshatyalaliswa ngokuyinhloko lixhomekeke kwiqondo lokuguqulwa komphezulu we-cellulose particles kunye ne-fineness of particles. Phakathi kwezi ether ze-cellulose ezingentla, i-methyl cellulose kunye ne-hydroxypropyl methyl cellulose zinezinga eliphezulu lokugcina amanzi.
(2) I-Methylcellulose i-soluble emanzini abandayo, kodwa kunzima ukunyibilika emanzini ashushu, kwaye isisombululo sayo samanzi sizinzileyo kakhulu kwi-pH = 3 ~ 12. Inokuhambelana kakuhle nestatshi, i-guar gum, njl. kunye nee-surfactants ezininzi. Xa iqondo lokushisa lifikelela kwiqondo lokushisa, i-phenomenon ye-gelation iyenzeka.
(3) Ukutshintsha kweqondo lobushushu kuyakuchaphazela kakhulu izinga lokugcinwa kwamanzi kwi-methyl cellulose. Ngokuqhelekileyo, okukhona ubushushu buphezulu, kokukhona ukugcinwa kwamanzi kubi. Ukuba ubushushu bodaka budlula i-40 °C, ukugcinwa kwamanzi kwe-methyl cellulose kuya kuba kubi kakhulu, okuya kuchaphazela kakhulu ukusebenza kodaka.
(4) I-Methyl cellulose inefuthe elibonakalayo ekusebenzeni kunye nokunamathela komdaka. “Ukuncamathela” apha kubhekiselele kuncamatheliso oluvakala phakathi kwesixhobo sofakelo somsebenzi kunye nenxalenye yodonga, oko kukuthi, ukuxhathisa kokucheba kodaka. I-adhesion inkulu, ukuxhathisa kwe-shear yodaka kukhulu, kwaye amandla afunwa ngabasebenzi kwinkqubo yokusetyenziswa nawo mkhulu, kwaye ukwakhiwa kodaka kubi. I-Methylcellulose adhesion ikwinqanaba eliphakathi kwimveliso ye-cellulose ether.
I-HPMC yi-hydroxypropyl methyl cellulose, eyi-non-ionic cellulose exutywe ne-ether eyenziwe kwi-cotton esulungekileyo emva konyango lwe-alkali, isebenzisa i-propylene oxide kunye ne-methyl chloride njengee-etherifying agents, kunye noluhlu lweempendulo. Iqondo lokutshintshwa ngokubanzi li-1.2 ukuya ku-2.0. Iipropati zayo ziyahluka ngokuxhomekeka kumlinganiselo womxholo we-methoxyl kunye nomxholo we-hydroxypropyl.
(1) IHydroxypropyl methylcellulose inyibilika ngokulula emanzini abandayo, kodwa iya kudibana nobunzima ekunyibilikeni kumanzi ashushu. Kodwa ubushushu bayo be-gelation emanzini ashushu buphezulu kakhulu kune-methyl cellulose. Ukutshatyalaliswa kwamanzi abandayo kuphuculwe kakhulu xa kuthelekiswa ne-methyl cellulose.
(2) I-viscosity ye-hydroxypropyl methylcellulose ihambelana nobukhulu bobunzima bayo be-molecular, kwaye ubukhulu be-molecular weight, buphezulu be-viscosity. Ubushushu buchaphazela i-viscosity yayo, njengoko izinga lokushisa linyuka, i-viscosity iyancipha. Kodwa i-viscosity yayo ayichatshazelwa kancinci kubushushu obuphezulu kune-methyl cellulose. Isisombululo saso sizinzile kwisitoreji kwiqondo lokushisa.
(3) I-Hydroxypropyl methylcellulose izinzile kwi-asidi kunye ne-alkali, kwaye isisombululo sayo samanzi sizinzileyo kakhulu kwi-pH = 2 ~ 12. I-Caustic soda kunye namanzi e-lime anempembelelo encinci ekusebenzeni kwayo, kodwa i-alkali inokukhawulezisa ukuchithwa kwayo kunye nokwandisa i-viscosity. I-Hydroxypropyl methylcellulose izinzile kwiityuwa eziqhelekileyo, kodwa xa ukuxinwa kwesisombululo setyuwa kuphezulu, i-viscosity yesisombululo se-hydroxypropyl methylcellulose ivame ukunyuka.
(4) Ugcino lwamanziihydroxypropyl methylcellulosekuxhomekeke kwisixa sayo sokongeza, i-viscosity, njl. Izinga lokugcinwa kwamanzi phantsi kwexabiso elifanayo lokudibanisa liphezulu kunelo le-methyl cellulose.
(5) I-Hydroxypropyl methylcellulose inokuxutywa kunye ne-polymer compounds e-soluble yamanzi ukwenza isisombululo kunye ne-uniform kunye ne-viscosity ephezulu. Okufana ne-polyvinyl alcohol, i-starch ether, i-gum yemifuno, njl.
(6) I-adhesion ye-hydroxypropyl methylcellulose kwisakhiwo sodaka iphezulu kune-methylcellulose.
(7) I-Hydroxypropyl methylcellulose inokumelana okungcono kwi-enzymes kune-methylcellulose, kwaye isisombululo sayo se-enzymatic degradation inokwenzeka iphantsi kune-methylcellulose.
Ixesha lokuposa: Apr-28-2024