HPMC (hydroxypropyl methylcellulose) yog ib hom polymer siv hauv kev lag luam kws tshuaj, zaub mov thiab tshuaj pleev ib ce. Nws yog ib qho cellulose derivative ua los ntawm chemically modifying natural cellulose. Ib qho ntawm cov khoom tseem ceeb ntawm HPMC yog nws cov viscosity, uas hloov pauv nyob ntawm ntau yam xws li qhov kub thiab txias.
Viscosity yog ib qho kev ntsuas ntawm cov kua los yog cov khoom tsis kam mus rau ntws. Rau HPMC polymers, viscosity yog ib qho tseem ceeb parameter uas cuam tshuam cov ntaub ntawv kev ua tau zoo nyob rau hauv ntau yam kev siv. Lub viscosity ntawm HPMC cuam tshuam los ntawm ntau yam xws li qhov hnyav molecular, qib hloov pauv, thiab kub.
Viscosity-Temperature Relationship ntawm HPMC Polymers
HPMC polymers qhia txog kev sib raug zoo ntawm cov viscosity thiab kub. Feem ntau hais lus, qhov kub thiab txias ua rau txo qis viscosity. Qhov kev coj cwj pwm no tuaj yeem piav qhia los ntawm:
1. Kub muaj feem xyuam rau hydrogen bonding
Nyob rau hauv HPMC polymers, intermolecular hydrogen bonds yog lub luag hauj lwm rau tsim ib tug muaj zog network qauv. Cov qauv network no pab txhawb cov viscosity ntawm cov khoom. Qhov kub thiab txias ua rau cov hydrogen bonds tawg, yog li txo cov kev sib cuam tshuam ntawm cov rog thiab yog li txo cov viscosity. Piv txwv li, qhov txo qis hauv qhov kub thiab txias ua rau muaj hydrogen bonds ntau dua, uas ua rau muaj kev nce hauv viscosity.
2. Qhov kub thiab txias cuam tshuam rau kev txav molecular
Ntawm qhov kub siab dua, cov molecules hauv HPMC polymer chains muaj zog kinetic ntau dua thiab tuaj yeem txav tau yooj yim dua. Qhov no nce molecular zog cuam tshuam cov polymer cov qauv thiab txo nws cov viscosity.
3. Kub muaj feem xyuam rau cov khoom hnyav
Lub viscosity ntawm HPMC polymer cov kev daws teeb meem kuj nyob ntawm qhov xwm txheej ntawm cov kuab tshuaj. Qee cov kuab tshuaj, xws li dej, pom qhov txo qis hauv viscosity vim qhov kub nce vim qhov tsis muaj zog ntawm hydrogen bonds. Hauv qhov sib piv, qee cov kuab tshuaj ua kom muaj viscosity ntawm qhov kub siab dua, xws li glycerol.
Nws yog tsim nyog sau cia tias qhov tshwj xeeb ntawm qhov kub-viscosity kev sib raug zoo rau HPMC yuav nyob ntawm seb cov qib tshwj xeeb ntawm polymer siv nrog rau cov concentration thiab hnyav siv. Piv txwv li, qee cov qib HPMC muaj qhov kub thiab txias, thaum lwm tus muaj qhov ruaj khov dua. Ntxiv mus, qhov viscosity ntawm HPMC nce raws li qhov concentration nce, thiab kev sib raug zoo ntawm kub thiab viscosity kuj hloov.
Qhov tseem ceeb ntawm Viscosity hauv HPMC Daim Ntawv Thov
Hauv kev lag luam kws tshuaj, HPMC yog cov khoom siv polymer feem ntau hauv cov tshuab xa tshuaj, qhov twg yuav tsum muaj kev tswj hwm tus nqi tso tshuaj thiab tus cwj pwm. Viscosity plays lub luag haujlwm tseem ceeb hauv cov tshuaj tso tawm raws li nws cuam tshuam cov tshuaj diffusion los ntawm polymer matrix. Tsis tas li ntawd, qhov viscosity ntawm HPMC kuj tseem ceeb hauv cov txheej txheem txheej txheej, vim tias cov viscosity siab dua yuav tsum tau ua kom zoo ib yam thiab txuas ntxiv.
Cov khoom noj khoom haus uas siv HPMC ua tus neeg sawv cev gelling thiab emulsifier yuav tsum muaj qhov tshwj xeeb viscosity los xyuas kom meej tias cov khoom tseem nyob ruaj khov thiab zoo ib yam hauv kev ntxhib los mos thiab thaum lub sij hawm ua. Ib yam li ntawd, cov tshuaj pleev ib ce uas siv HPMC ua cov khoom ua kom tuab, xws li tshuaj zawv plaub hau thiab tshuaj pleev ib ce, yuav tsum tau hloov kho qhov concentration thiab viscosity ntawm HPMC raws li cov khoom xav tau.
nyob rau hauv xaus
HPMC yog cov khoom siv ntau yam polymer uas ua rau muaj kev sib raug zoo ntawm cov viscosity thiab kub. Qhov kub nce ntxiv ua rau txo qis hauv viscosity, feem ntau yog vim qhov kub ntawm qhov kub ntawm qhov sib txuas ntawm hydrogen, molecular zog, thiab cov khoom hnyav. Kev nkag siab txog qhov kub-viscosity kev sib raug zoo ntawm HPMC polymers tuaj yeem pab tsim cov khoom nrog cov khoom zoo sib xws thiab xav tau. Yog li ntawd, txoj kev kawm ntawm HPMC viscosity yog qhov tseem ceeb los xyuas kom meej qhov ua tau zoo ntawm ntau yam kev siv hauv kev lag luam tshuaj, zaub mov thiab tshuaj pleev ib ce.
Post lub sij hawm: Oct-08-2023