Hydroxypropyl methylcellulose (HPMC) yog ntau yam polymer siv nyob rau hauv ntau yam kev lag luam xws li tshuaj, kev tsim kho, khoom noj khoom haus, thiab tshuaj pleev ib ce. Nws yog ib qho cellulose derivative uas nthuav tawm ntau yam khoom nyob ntawm nws cov qib tshwj xeeb. Cov qib sib txawv ntawm HPMC feem ntau yog qhov txawv ntawm lawv cov viscosity, qib ntawm kev hloov pauv, qhov loj me, thiab lub hom phiaj ntawm kev thov tshwj xeeb.
1. Qib viscosity
Viscosity yog ib qho tseem ceeb parameter uas txhais cov qib ntawm HPMC. Nws hais txog lub thickness los yog tsis kam mus ntws ntawm HPMC tov. HPMC muaj viscosity ntau los ntawm qis mus rau siab thiab feem ntau yog ntsuas hauv centipoise (cP) thaum yaj hauv dej. Qee cov qib viscosity feem ntau suav nrog:
Cov qib viscosity tsawg (piv txwv li, 3 txog 50 cP): Cov qib no yog siv rau hauv cov ntawv thov uas xav tau cov tshuaj viscosity tsawg, xws li hauv kev lag luam khoom noj xws li stabilizers, thickeners, lossis emulsifiers.
Cov qib viscosity nruab nrab (piv txwv li, 100 txog 4000 cP): Nruab nrab viscosity HPMC yog siv los tswj cov tshuaj tsim tawm thiab ua cov binders hauv cov ntsiav tshuaj.
Cov qib viscosity siab (piv txwv li, 10,000 txog 100,000 cP): Cov qib viscosity siab feem ntau yog siv rau hauv kev tsim kho, tshwj xeeb tshaj yog cov cement-based mortars, adhesives, thiab plasters, uas lawv txhim kho kev ua haujlwm, dej tuav, thiab adhesion.
2. Degree of Hloov (DS) thiab Molar Hloov (MS)
Qib ntawm kev hloov pauv yog hais txog qhov nruab nrab ntawm cov pawg hydroxyl ntawm cov cellulose molecule uas hloov los ntawm methoxy (-OCH3) lossis hydroxypropyl (-OCH2CHOHCH3) pawg. Qhov degree ntawm kev hloov pauv cuam tshuam rau solubility, gelation kub, thiab viscosity ntawm HPMC. Cov qib HPMC raug cais raws li cov ntsiab lus methoxy thiab hydroxypropyl:
Cov ntsiab lus Methoxy (28-30%): Cov ntsiab lus methoxy ntau dua feem ntau ua rau qis dua gelation thiab siab dua viscosities.
Hydroxypropyl cov ntsiab lus (7-12%): Ua kom cov hydroxypropyl cov ntsiab lus feem ntau txhim kho solubility hauv dej txias thiab ua kom yooj yim dua.
3. Particle loj faib
Qhov loj me me ntawm HPMC hmoov tuaj yeem sib txawv, cuam tshuam rau lawv qhov kev sib cais thiab kev ua haujlwm hauv ib daim ntawv thov. Qhov zoo dua cov khoom, lawv yaj sai dua, ua rau lawv zoo dua rau cov ntawv thov uas xav tau dej sai, xws li kev lag luam khoom noj. Hauv kev tsim kho, nws yog qhov zoo tshaj plaws los siv cov qib coarser kom zoo dua dispersion nyob rau hauv qhuav mix.
4. Cov qhab nias tshwj xeeb
HPMC muaj nyob rau hauv ntau qib, haum rau cov kev xav tau tshwj xeeb hauv kev lag luam:
Pharmaceutical grade: Siv los ua ib daim ntawv khi, zaj duab xis qub, thiab tus neeg saib xyuas kev tso tawm hauv qhov ncauj cov ntaub ntawv. Nws ua tau raws li cov qauv purity nruj thiab feem ntau muaj cov viscosity tshwj xeeb thiab cov khoom hloov pauv.
Qib kev tsim kho: HPMC qib no yog tsim los siv rau hauv cov cement thiab gypsum-based khoom. Nws txhim kho kev tuav dej, ua haujlwm tau zoo, thiab ua kom zoo hauv plasters, mortars, thiab pobzeb adhesives. Cov qib viscosity siab feem ntau yog siv hauv cheeb tsam no.
Khoom noj khoom haus qib: HPMC qib zaub mov tau pom zoo siv los ua khoom noj khoom haus ntxiv (E464) thiab tuaj yeem siv ua cov thickener, emulsifier, thiab stabilizer nyob rau hauv ntau yam khoom, nrog rau cov khoom ci thiab khoom noj siv mis. Nws yuav tsum ua raws li cov cai tswj kev nyab xeeb zaub mov thiab feem ntau tsis muaj impurities.
Qib Tshuaj pleev ib ce: Hauv cov khoom tu tus kheej, HPMC yog siv los ua cov thickener, emulsifier, thiab zaj duab xis qub. Nws muab kev ntxhib los mos rau cream, tshuaj pleev, thiab tshuaj zawv plaub hau.
5. Hloov cov qib
Qee daim ntawv thov yuav tsum tau hloov kho HPMC qib, qhov twg cov polymer yog hloov kho los txhim kho cov khoom tshwj xeeb:
Hla-txuas HPMC: Qhov kev hloov kho no txhim kho gel lub zog thiab kev ruaj ntseg hauv kev tswj-tso formulations.
Hydrophobic modified HPMC: Hom HPMC no yog siv rau hauv cov formulations uas yuav tsum tau txhim khu kev tiv thaiv dej, xws li coatings thiab xim.
6. Gel kub qib
Lub gel kub ntawm HPMC yog qhov kub ntawm qhov kev daws teeb meem pib tsim cov gel. Nws nyob ntawm qhov kev hloov pauv thiab viscosity. Cov qib sib txawv muaj nyob ntawm qhov xav tau gel kub:
Qib gel kub qis: Cov qib gel no nyob rau hauv qis qis, ua rau lawv haum rau cov huab cua kub lossis cov txheej txheem tshwj xeeb uas yuav tsum muaj qhov kub thiab txias.
Cov qib siab gel kub: Cov no yog siv rau hauv cov ntawv thov uas yuav tsum tau tsim cov gel ntawm qhov kub siab dua, xws li qee cov tshuaj formulations.
HPMC muaj nyob rau ntau qib kom tau raws li cov kev xav tau tshwj xeeb ntawm kev lag luam sib txawv. Kev xaiv ntawm qib HPMC nyob ntawm qhov xav tau viscosity, qib ntawm kev hloov pauv, qhov loj me, thiab cov ntawv thov tshwj xeeb. Txawm hais tias siv hauv cov tshuaj, kev tsim kho, khoom noj lossis tshuaj pleev ib ce, qib raug ntawm HPMC yog qhov tseem ceeb rau kev ua tiav cov khoom xav tau thiab kev ua haujlwm ntawm cov khoom kawg.
Post lub sij hawm: Aug-27-2024