HPMC (Hydroxypropyl Methyl Cellulose) yog ib qho kev siv cellulose derivative uas tau siv dav hauv ntau qhov chaw lag luam, tshwj xeeb tshaj yog hauv kev tswj viscosity thiab thickening zog. Vim nws cov qauv tshuaj tshwj xeeb thiab lub cev muaj zog, HPMC tuaj yeem txhim kho cov viscosity, stability thiab rheological zog ntawm cov khoom lag luam. Yog li ntawd, nws tau siv dav hauv cov txheej txheem, cov khoom siv hauv tsev, tshuaj, tshuaj pleev ib ce, zaub mov thiab lwm yam.
Cov yam ntxwv tseem ceeb ntawm HPMC
HPMC yog cov khoom siv polymer ua los ntawm kev hloov kho ntuj tsim cellulose. Nws cov saw molecular muaj cov pab pawg hydrophilic thiab pawg hydrophobic, yog li nws muaj dej solubility zoo thiab cov organic hnyav compatibility. Nws dissolves nyob rau hauv dej txias los ua ib tug pob tshab los yog translucent viscous tov. Cov yam ntxwv tseem ceeb ntawm HPMC suav nrog:
Cov khoom thickening zoo heev: HPMC tuaj yeem ua kom cov viscosity ntawm cov kev daws teeb meem ntawm qhov tsis tshua muaj siab, muab cov teebmeem thickening zoo dua. Qhov no ua rau nws muaj qhov tseem ceeb hauv cov khoom lag luam xws li cov khoom siv hauv tsev thiab cov txheej txheem los txhim kho cov khoom siv kev ua haujlwm.
Kev tswj viscosity zoo: HPMC tuaj yeem ua tiav kev tswj cov viscosity los ntawm kev kho nws qhov hnyav molecular thiab qib ntawm kev hloov pauv (xws li methoxy thiab hydroxypropyl hloov pauv) kom tau raws li qhov xav tau ntawm cov ntawv thov sib txawv. Piv txwv li, hauv kev lag luam txheej, HPMC nrog cov viscosities sib txawv tuaj yeem muab cov qib sib txawv thiab ua haujlwm tau zoo rau cov txheej txheem.
Kev hloov kho rheological zoo heev: Cov khoom rheological ntawm HPMC tuaj yeem hloov pauv nrog kev hloov pauv ntawm cov nqi shear. Qhov no txhais tau hais tias thaum zoo li qub, nws tsim cov qauv viscos heev, thiab cov viscosity txo qis thaum shearing quab yuam siv (xws li nplawm lossis txau), ua rau cov khoom siv yooj yim. Ntawm qee cov khoom siv hauv pem teb, tus yam ntxwv ntawm HPMC yog qhov tseem ceeb tshwj xeeb.
Zoo biocompatibility thiab non-toxicity: HPMC yog muab los ntawm tej yam ntuj tso cellulose, muaj zoo biocompatibility, yog tsis muaj tshuaj lom, tsis ua rau khaus, thiab ua tau raws li tej kev tiv thaiv ib puag ncig. Yog li ntawd, nws muaj kev ruaj ntseg ntau dua nyob rau hauv cov tshuaj pleev ib ce, tshuaj, khoom noj khoom haus, thiab lwm yam. Nws kuj yog dav siv nyob rau hauv high-end teb.
Thickening mechanism ntawm HPMC hauv cov khoom lag luam
Cov khoom thickening ntawm HPMC feem ntau yog vim nws cov qauv molecular thiab kev cuam tshuam ntawm cov molecules hauv cov tshuaj. Thaum HPMC yaj nyob rau hauv dej los yog lwm yam kuab tshuaj, nws macromolecular chains yuav nthuav thiab tsim muaj zog hydrogen bonds thiab van der Waals rog nrog hnyav molecules, yog li ua rau lub viscosity ntawm lub system. Tsis tas li ntawd, peb-dimensional network qauv tsim los ntawm HPMC hauv kev daws teeb meem kuj yog tus yuam sij rau nws cov thickening kev ua tau zoo. Cov saw hlau molecular nyob rau hauv cov tshuaj HPMC yog intertwined los tsim ib tug network qauv, uas yuav txo tau cov fluidity ntawm cov tshuaj thiab yog li nthuav tawm viscosity ntau dua.
Rau cov xwm txheej sib txawv, qhov viscosity ntawm HPMC tuaj yeem hloov kho raws li hauv qab no:
Kev hloov ntawm qhov hnyav molecular: Lub viscosity ntawm HPMC feem ntau yog proportional rau nws qhov hnyav molecular. Qhov loj dua qhov hnyav molecular, qhov siab dua qhov viscosity ntawm cov tshuaj. Yog li ntawd, los ntawm kev xaiv HPMC cov khoom uas muaj qhov sib txawv molecular hnyav, kev daws teeb meem nrog cov viscosities sib txawv tuaj yeem ua tau raws li qhov xav tau ntawm ntau yam khoom lag luam.
Kev tswj hwm qib ntawm kev hloov pauv: Cov nyhuv thickening ntawm HPMC kuj tseem cuam tshuam nrog nws qhov kev hloov pauv. Qhov siab dua qhov kev hloov pauv, qhov muaj zog ntawm hydrophilicity thiab qhov zoo dua cov nyhuv thickening. Los ntawm kev tswj cov qib ntawm kev hloov ntawm HPMC cov methoxy thiab hydroxypropyl pawg, nws cov viscosity muaj peev xwm tswj tau meej.
Cov nyhuv ntawm cov tshuaj concentration: Lub concentration ntawm HPMC nyob rau hauv cov tshuaj kuj ncaj qha cuam tshuam nws viscosity. Feem ntau hais lus, qhov siab dua qhov concentration ntawm cov tshuaj, qhov viscosity ntau dua. Yog li, los ntawm kev kho qhov concentration ntawm HPMC, kev tswj xyuas meej ntawm kev daws cov viscosity tuaj yeem ua tiav.
Cov cheeb tsam thov thiab thickening los ntawm HPMC
Cov ntaub ntawv hauv tsev: HPMC feem ntau yog siv los ua cov thickener thiab viscosity regulator nyob rau hauv cov cement-based mortars, pobzeb adhesives, thiab self-leveling pem teb cov ntaub ntawv nyob rau hauv lub tsev cov ntaub ntawv. Nws cov nyhuv thickening ua rau kom cov dej khaws cia ntawm cov ntaub ntawv no, txhim kho lawv cov kev ua haujlwm, thiab tiv thaiv kev tawg lossis shrinkage. Tshwj xeeb tshaj yog nyob rau hauv ib puag ncig kub, HPMC tuaj yeem txuas ntxiv lub sijhawm qhib ntawm cov khoom siv thiab ua kom nws ua haujlwm tau zoo.
Txheej thiab xim: Hauv kev lag luam coatings, HPMC yog siv los ua cov thickener thiab tshem tawm cov neeg sawv cev los txhim kho cov adhesion ntawm txheej thiab txhim kho lawv cov qib thiab sag kuj thaum lub sij hawm txheej. Nyob rau tib lub sijhawm, HPMC tuaj yeem pab cov xim kom muaj cov khoom sib xws, tiv thaiv cov xim sib haum xeeb, thiab ua rau cov yeeb yaj kiab txheej smoother thiab zoo ib yam.
Tshuaj thiab Tshuaj pleev ib ce: Hauv kev npaj tshuaj, HPMC feem ntau yog siv los tswj tus nqi tso tawm ntawm cov tshuaj, raws li cov ntsiav tshuaj txheej cov ntaub ntawv thiab capsule plhaub. Nws cov khoom zoo thickening pab txhim kho kev ruaj ntseg ntawm cov tshuaj thiab ncua lub sij hawm ntawm cov nyhuv tshuaj. Nyob rau hauv cov tshuaj pleev ib ce, HPMC yog dav siv nyob rau hauv cov tshuaj pleev ib ce, cream, conditioners thiab lwm yam khoom los ua kom lub viscosity thiab stability ntawm cov khoom thaum pab txhawb lub silky xav thiab moisturizing nyhuv thaum thov.
Kev lag luam khoom noj khoom haus: HPMC feem ntau siv hauv kev lag luam khoom noj khoom haus ua cov thickener thiab stabilizer, tshwj xeeb tshaj yog nyob rau hauv cov khoom noj siv mis, condiments, jellies thiab dej haus. Nws cov khoom tsis muaj tshuaj lom thiab tsis muaj ntxhiab tsw ua rau nws muaj kev nyab xeeb thiab txhim khu kev qha thickening tus neeg sawv cev uas txhim kho kev ntxhib los mos thiab qhov ncauj ntawm cov khoom noj.
HPMC tau dhau los ua cov khoom siv tseem ceeb hauv cov khoom lag luam niaj hnub no vim nws qhov kev ua haujlwm zoo heev thiab muaj peev xwm tswj tau viscosity. Los ntawm kev kho nws qhov hnyav molecular, qib kev hloov pauv thiab kev daws teeb meem, HPMC tuaj yeem ua tau raws li qhov xav tau ntawm viscosity ntawm cov khoom lag luam sib txawv. Nyob rau tib lub sijhawm, nws cov khoom tsis muaj tshuaj lom, nyab xeeb thiab ib puag ncig zoo kuj tau ua rau nws siv dav hauv cov khoom noj, tshuaj thiab tshuaj pleev ib ce thiab lwm yam. Nyob rau hauv lub neej yav tom ntej, nrog kev nce qib ntawm kev tshawb fawb thiab thev naus laus zis, kev thov cov xwm txheej ntawm HPMC yuav nthuav dav dua, thiab nws cov txiaj ntsig hauv kev tswj viscosity thiab thickening kev ua tau zoo yuav raug tshawb nrhiav thiab siv ntxiv.
Post lub sij hawm: Sep-25-2024