Cellulose ether (Cellulose Ether) yog ib qho polymer compound muab rho tawm los ntawm cov nroj tsuag ntuj cellulose thiab tau los ntawm kev hloov kho tshuaj. Muaj ntau ntau hom cellulose ether, ntawm cov uas hydroxypropyl methylcellulose (HPMC) yog cov feem ntau. HPMC muaj dej solubility zoo heev, thickening, ncua kev kawm ntawv, film-forming thiab stability, thiab yog dav siv nyob rau hauv lub tsev cov ntaub ntawv, tshuaj, khoom noj khoom haus thiab tshuaj txhua hnub.
1. Lub cev thiab tshuaj lom neeg ntawm HPMC
HPMC yog ib qho derivative tau los ntawm kev hloov cov hydroxyl hauv cov qauv cellulose nrog methoxy thiab hydroxypropoxy. Nws muaj cov dej zoo solubility thiab tuaj yeem yaj sai sai hauv dej txias los tsim cov kua dej ntshiab thiab khov kho, thiab nws cov tshuaj qhia tau hais tias muaj qee yam thermal stability ntawm qhov kub thiab txias. Ntawm qhov qis dua, cov tshuaj HPMC coj tus cwj pwm zoo li cov kua dej pseudoplastic, uas txhais tau hais tias nws muaj cov khoom zoo rheological, thiab cov viscosity txo qis thaum nplawm los yog siv kev ntxhov siab, tab sis cov viscosity rov qab sai sai tom qab lub zog nres.
Lub viscosity ntawm HPMC tuaj yeem tswj tau los ntawm kev kho nws qhov hnyav molecular thiab qib ntawm kev hloov pauv, uas ua rau nws yooj yim heev rau kev siv hauv ntau qhov chaw. Hais txog kev txhim kho cov khoom ruaj khov, HPMC tuaj yeem ua lub luag haujlwm los ntawm cov txheej txheem hauv qab no.
2. Mechanisms ntawm HPMC los txhim kho cov khoom ruaj khov
Thickening thiab rheological kev cai
Raws li cov thickener, HPMC tuaj yeem ua kom cov viscosity ntawm cov kev daws teeb meem los yog slurries, yog li ua kom cov viscosity stability ntawm lub system. Rau qee cov khoom lag luam uas yuav tsum tau tswj cov dej ntws, xws li txheej txheej, tshuaj pleev ib ce, thiab tshuaj tua kab mob, HPMC tuaj yeem pab tiv thaiv cov khoom tsis zoo los ntawm kev daws thiab txuas ntxiv lub neej txee ntawm cov khoom. Tsis tas li ntawd, qhov pseudoplasticity ntawm HPMC tso cai rau cov khoom kom ruaj khov thaum lub sijhawm khaws cia thiab kev thauj mus los, thiab pab txhawb kev khiav thiab kev siv thaum siv.
Kev ncua thiab dispersion stability
Nyob rau hauv qee lub tshuab dispersed, kev ncua kev ruaj ntseg ntawm cov khoom siv los yog cov roj tee hauv cov kua dej yog tus yuam sij rau kev cuam tshuam cov khoom zoo. HPMC tuaj yeem tsim cov qauv sib xws hauv cov kua los ntawm nws cov tshuaj thickening thiab hydrophilic pawg hauv nws cov qauv molecular, qhwv cov khoom tawg mus tiv thaiv particle agglomeration, sedimentation los yog stratification, yog li txhim kho kev ruaj ntseg ntawm cov kab mob sib kis. Qhov no yog qhov tseem ceeb tshwj xeeb rau cov khoom xws li emulsions, suspensions, thiab coatings.
Film-forming zog thiab tiv thaiv txheej txheej
Cov khoom ua yeeb yaj kiab ntawm HPMC ua kom nws tsim cov yeeb yaj kiab zoo ib yam ntawm cov khoom tom qab ziab. Cov yeeb yaj kiab no tuaj yeem tsis tsuas yog tiv thaiv cov khoom xyaw nquag hauv cov khoom los ntawm oxidized los yog paug los ntawm lub ntiaj teb sab nraud, tab sis kuj tseem tuaj yeem siv rau hauv kev lag luam tshuaj thiab zaub mov los tswj tus nqi ntawm cov tshuaj tso tawm los yog ncua lub txee lub neej ntawm cov zaub mov. Tsis tas li ntawd, cov txheej txheem tiv thaiv tsim los ntawm HPMC tuaj yeem tiv thaiv dej poob thiab txhim kho cov khoom siv hauv tsev xws li cement mortar thiab coatings.
Thermal stability thiab kub teb
HPMC qhia kev ruaj ntseg zoo ntawm qhov kub sib txawv. Nws viscosity nyob rau hauv aqueous kua yog rhiab heev rau qhov kub thiab txias hloov, tab sis cov kua viscosity tseem nyob tas li ntawm chav tsev kub. Tsis tas li ntawd, HPMC tau rov qab gelation ntawm qhov kub thiab txias, uas ua rau nws muaj qhov tshwj xeeb stabilizing nyhuv hauv cov tshuab uas yuav tsum tau rhiab rau qhov kub thiab txias (xws li zaub mov thiab tshuaj).
3. Daim ntawv thov ntawm HPMC los txhim kho kev ruaj ntseg hauv ntau qhov chaw
Kev siv cov khoom siv hauv tsev
Hauv cov khoom siv hauv tsev xws li cement mortar thiab pobzeb nplaum, HPMC feem ntau yog siv los kho qhov sib xws ntawm slurry thiab ua rau kom muaj dej thiab ua haujlwm tau zoo thaum tsim kho. Tsis tas li ntawd, HPMC ua haujlwm tau zoo ncua sijhawm cov evaporation ntawm cov dej los ntawm kev tsim cov yeeb yaj kiab tom qab ziab, tsis txhob tawg lossis ua kom lub sijhawm ua haujlwm luv luv, yog li txhim kho qhov ruaj khov ntawm cov khoom siv thiab kev tsim kho kom zoo.
Daim ntawv thov hauv kev npaj tshuaj
Hauv kev npaj tshuaj, HPMC yog dav siv los ua cov thickener, zaj duab xis qub thiab tswj kev tso tawm tus neeg sawv cev. Nws cov nyhuv thickening tuaj yeem txhim kho kev ruaj ntseg ntawm cov khoom xyaw nquag hauv kev tshem tawm lossis emulsions thiab tiv thaiv cov tshuaj stratification lossis nag lossis daus. Tsis tas li ntawd, cov yeeb yaj kiab tiv thaiv tsim los ntawm HPMC tuaj yeem tswj hwm qhov tso tawm ntawm cov tshuaj thiab ua kom lub sijhawm ntev ntawm kev siv tshuaj. Tshwj xeeb tshaj yog nyob rau hauv sustained-tso npaj, HPMC yog ib qho ntawm cov excipients.
Kev siv hauv cov khoom noj
Hauv kev lag luam khoom noj khoom haus, HPMC feem ntau yog siv los ua cov thickener thiab emulsifier los txhim kho kev ntxhib los mos thiab saj ntawm cov zaub mov. Nws muaj peev xwm hydration zoo tuaj yeem khaws cov dej noo thiab ua kom lub neej txee ntawm cov khoom. Piv txwv li, hauv cov khoom ci, HPMC tuaj yeem tiv thaiv dej los ntawm evaporating sai heev thiab txhim kho qhov fluffiness thiab softness ntawm qhob cij thiab ncuav mog qab zib. Tsis tas li ntawd, cov cuab yeej ua yeeb yaj kiab ntawm HPMC kuj tuaj yeem siv rau txheej cov zaub mov kom tiv thaiv oxidation thiab deterioration.
Kev siv rau hauv cov khoom siv tshuaj txhua hnub
Hauv cov khoom siv tshuaj lom neeg niaj hnub xws li tshuaj ntxuav tes, tshuaj zawv plaub hau, thiab cov khoom tu tawv nqaij, HPMC feem ntau siv los ua cov thickener thiab stabilizer. Nws tuaj yeem ua kom cov khoom sib xws, txhim kho qhov sib xws ntawm kev ntxhib los mos, ua rau emulsions lossis gel cov khoom siv yooj yim dua thiab tsis tshua muaj stratify lossis precipitate. Tib lub sijhawm, cov nyhuv moisturizing ntawm HPMC kuj pab txhim kho cov nyhuv moisturizing ntawm cov khoom tu tawv nqaij.
Raws li ib qho tseem ceeb cellulose ether derivative, HPMC yog dav siv nyob rau hauv ntau yam lag luam vim nws zoo heev thickening, film-forming, ncua kev kawm ntawv thiab thermal stability, tshwj xeeb tshaj yog nyob rau hauv kev txhim kho cov khoom stability. Txawm hais tias nyob rau hauv cov khoom siv hauv tsev, tshuaj, khoom noj lossis cov khoom siv tshuaj txhua hnub, HPMC tuaj yeem txuas ntxiv lub neej kev pab cuam ntawm cov khoom thiab txhim kho nws cov kev ua tau zoo los ntawm ntau yam txheej txheem xws li kev txhim kho cov viscosity ntawm lub cev, kho cov khoom siv rheological, txhim kho kev ncua thiab dispersion stability, thiab tsim ib zaj duab xis tiv thaiv. Nyob rau hauv lub neej yav tom ntej, nrog rau kev nce qib ntawm thev naus laus zis thiab kev nthuav dav ntxiv ntawm daim ntawv thov kev lag luam, daim ntawv thov muaj peev xwm ntawm HPMC hauv ntau thaj chaw yuav raug nthuav tawm ntxiv.
Post lub sij hawm: Sep-21-2024