Focus on Cellulose ethers

Hydroxypropyl methyl cellulose (HPMC) yog dab tsi yog qhov kev qhia tseem ceeb?

Hydroxypropyl methyl cellulose (HPMC) yog ntau yam thiab dav siv uas tsis yog-ionic cellulose ether, feem ntau siv hauv ntau qhov kev lag luam vim nws cov khoom tshwj xeeb. Cov kev qhia tseem ceeb ntawm HPMC tuaj yeem faib dav dav rau hauv lub cev, tshuaj, thiab kev ua haujlwm, txhua qhov ua rau nws tsim nyog rau cov ntawv thov tshwj xeeb.

1. Lub cev muaj zog
a. Qhov tshwm sim
HPMC feem ntau yog cov hmoov dawb rau cov hmoov dawb, tsis muaj ntxhiab thiab tsis qab, qhia nws txoj kev huv thiab tsim nyog rau kev siv hauv cov ntawv thov xws li tshuaj thiab khoom noj.

b. Particle Loj
Qhov loj me me ntawm HPMC tuaj yeem cuam tshuam nws cov solubility thiab dispersibility hauv dej los yog lwm yam kuab tshuaj. Nws yog feem ntau muaj nyob rau hauv ntau qib, qhov twg cov particle loj tis ranges ntawm nplua mus rau coarse hmoov. Ib qho me me me me feem ntau ua rau kom nrawm nrawm dua.

c. Kev ceev ceev
Kev ceev ntom yog qhov ntsuas tseem ceeb, tshwj xeeb rau kev tuav thiab ua cov hom phiaj. Nws feem ntau yog li ntawm 0.25 txog 0.70 g / cm³, cuam tshuam rau cov khoom ntws thiab cov khoom ntim khoom.

d. Cov ntsiab lus noo noo
Cov dej noo nyob rau hauv HPMC yuav tsum tsawg heev kom muaj kev ruaj ntseg thiab tiv thaiv clumping thaum khaws cia. Cov ntsiab lus noo noo feem ntau yog qis dua 5%, feem ntau nyob ib ncig ntawm 2-3%.

2. Cov khoom siv tshuaj
a. Methoxy thiab Hydroxypropyl Cov ntsiab lus
Cov qib hloov pauv ntawm methoxy (–OCH₃) thiab hydroxypropyl (–OCH₂CH₂OH) pawg yog cov cim tseem ceeb ntawm cov tshuaj, cuam tshuam rau kev solubility, gelation kub, thiab viscosity ntawm HPMC. Cov ntsiab lus methoxy zoo li ntawm 19-30%, thiab cov ntsiab lus hydroxypropyl los ntawm 4-12%.

b. viscosity
Viscosity yog ib qho ntawm cov khoom tseem ceeb tshaj plaws, txhais tau tias HPMC qhov kev ua tau zoo hauv kev siv. Nws yog ntsuas nyob rau hauv aqueous daws, feem ntau siv ib tug viscometer rotational. Viscosity tuaj yeem nyob ntawm ob peb centipoises (cP) mus rau ntau dua 100,000 cP. Qhov ntau yam no tso cai rau customization nyob rau hauv ntau yam kev lag luam txheej txheem.

c. Tus nqi pH
Cov pH ntawm 2% HPMC cov tshuaj feem ntau poob ntawm 5.0 thiab 8.0. Qhov kev tsis sib haum xeeb no yog qhov tseem ceeb rau kev sib raug zoo hauv cov qauv tsim, tshwj xeeb hauv cov tshuaj thiab cov khoom noj.

d. Purity thiab impurities
High purity yog qhov tseem ceeb, tshwj xeeb tshaj yog rau cov zaub mov thiab qib tshuaj. Cov impurities xws li cov hlau hnyav (xws li, txhuas, arsenic) yuav tsum tsawg heev. Cov lus qhia tshwj xeeb feem ntau xav tau cov hlau hnyav tsawg dua 20 ppm.

3. Cov khoom siv ua haujlwm
a. Solubility
HPMC yog soluble nyob rau hauv ob qho tib si dej txias thiab kub, tsim kom meej meej los yog me ntsis turbid, viscous daws. Qhov no dual solubility yog qhov zoo rau ntau yam formulations, tso cai rau kev hloov pauv hauv kev ua haujlwm.

b. Thermal Gelation
Cov cuab yeej tshwj xeeb ntawm HPMC yog nws lub peev xwm los tsim cov gels thaum cua sov. Qhov kub ntawm gelation nyob ntawm seb qhov kev hloov pauv thiab qhov concentration. Hom gelation kub yog li ntawm 50 ° C txog 90 ° C. Cov cuab yeej no yog siv nyob rau hauv daim ntawv thov xws li kev tswj-tso formulations nyob rau hauv pharmaceuticals.

c. Muaj peev xwm ua yeeb yaj kiab
HPMC tuaj yeem tsim cov yeeb yaj kiab muaj zog, hloov tau yooj yim, thiab pob tshab. Cov cuab yeej no yog siv dav hauv coatings, encapsulation ntawm pharmaceuticals, thiab zaub mov glazing.

d. Kev ua Ntog
HPMC nthuav tawm cov khoom ua haujlwm saum npoo av, muab emulsification thiab stabilization teebmeem. Qhov no yog tshwj xeeb tshaj yog pab tau nyob rau hauv cov tshuaj pleev ib ce, tshuaj, thiab zaub mov industries qhov twg emulsions ruaj khov yuav tsum tau.

e. Kev tuav dej
Ib qho ntawm cov khoom tseem ceeb ntawm HPMC yog nws lub peev xwm tuav dej. Nws muaj txiaj ntsig zoo hauv kev khaws cov dej noo, uas yog qhov tseem ceeb hauv kev siv xws li mortars, plasters, thiab tshuaj pleev ib ce.

4. Cov ntawv thov tshwj xeeb thiab lawv cov kev xav tau
a. Pharmaceuticals
Hauv kev lag luam kws tshuaj, HPMC yog siv los ua cov ntaub ntawv, zaj duab xis-yav dhau los, thiab tswj-tso tus neeg sawv cev. Cov kev ntsuas xws li purity siab, cov qib viscosity tshwj xeeb, thiab cov qib hloov pauv tau yog qhov tseem ceeb los xyuas kom meej qhov ua tau zoo thiab kev nyab xeeb hauv kev xa tshuaj.

b. Kev tsim kho
Hauv kev tsim kho, tshwj xeeb hauv cov khoom siv cement-based thiab gypsum-based, HPMC yog siv los txhim kho kev ua haujlwm, dej tuav, thiab adhesion. Ntawm no, viscosity, particle loj, thiab cov khoom tuav dej yog qhov tseem ceeb.

c. Kev lag luam zaub mov
HPMC yog ua hauj lwm raws li ib tug thickener, emulsifier, thiab stabilizer nyob rau hauv ntau yam khoom noj khoom haus. Rau cov ntawv thov zaub mov, cov ntsuas kev txaus siab suav nrog kev ua siab dawb huv, tsis muaj tshuaj lom, thiab tshwj xeeb viscosity profiles kom ntseeg tau tias kev ntxhib los mos thiab ruaj khov.

d. Kev Kho Tus Kheej thiab Tshuaj pleev ib ce
Hauv cov khoom siv tu tus kheej, HPMC muaj nuj nqis rau nws cov thickening, emulsifying, thiab cov khoom ua yeeb yaj kiab. Cov ntsuas tseem ceeb suav nrog solubility, viscosity, thiab purity, kom ntseeg tau tias muaj kev sib raug zoo nrog lwm cov khoom xyaw thiab kev ruaj ntseg ntawm cov khoom kawg.

5. Kev Tswj Xyuas Zoo thiab Kev Ntsuas Kev Ntsuas
Kev tswj hwm zoo ntawm HPMC suav nrog kev sim nruj ntawm nws lub cev thiab tshuaj lom neeg. Cov kev sim ua haujlwm feem ntau suav nrog:

a. Kev ntsuas viscosity
Siv cov viscometer rotational los txiav txim siab viscosity ntawm HPMC cov kev daws teeb meem.

b. Hloov Kev Ntsuas
Cov txheej txheem zoo li NMR spectroscopy yog siv los txiav txim siab cov ntsiab lus methoxy thiab hydroxypropyl.

c. Moisture Content Determination
Karl Fischer titration lossis poob ntawm kev ziab (LOD) yog ua haujlwm.

d. Kev ntsuas particle loj
Laser diffraction thiab sieving txoj kev los xyuas kom meej particle loj tis.

e. Kev ntsuas pH
Lub pH meter yog siv los ntsuas pH ntawm HPMC cov kev daws teeb meem kom ntseeg tau tias lawv poob rau hauv qhov kev teev tseg.

f. Heavy Metal Testing
Atomic absorption spectroscopy (AAS) lossis inductively coupled plasma (ICP) tsom xam rau kev kuaj xyuas cov hlau tsis huv.

Hydroxypropyl methyl cellulose (HPMC) yog multifunctional additive nrog ntau yam kev siv, yuav tsum muaj kev nkag siab ntxaws txog nws cov kev qhia. Lub zog lub cev xws li cov tsos, particle loj, ntom ntom ntom, thiab cov ntsiab lus noo noo, kev ua. Cov khoom siv tshuaj muaj xws li methoxy thiab hydroxypropyl cov ntsiab lus, viscosity, pH, thiab purity dictate nws tsim nyog rau cov kev siv tshwj xeeb. Cov khoom ua haujlwm xws li solubility, thermal gelation, film-forming muaj peev xwm, deg kev ua si, thiab dej tuav ntxiv underscore nws versatility. Los ntawm kev ua raws li kev tswj hwm nruj, HPMC tuaj yeem siv tau zoo thoob plaws kev lag luam, ua tiav ntau lub luag haujlwm los ntawm kev siv tshuaj mus rau kev tsim kho.


Post lub sij hawm: May-22-2024
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