HPMC los yog hydroxypropyl methylcellulose yog ib yam khoom siv ntau yam siv hauv ntau yam lag luam xws li tshuaj, tshuaj pleev ib ce thiab zaub mov. Nws yog dav siv los ua cov thickener thiab emulsifier, thiab nws cov viscosity hloov nyob ntawm qhov kub thiab txias nws raug. Hauv tsab xov xwm no, peb yuav tsom mus rau kev sib raug zoo ntawm viscosity thiab kub hauv HPMC.
Viscosity txhais tau hais tias yog ib qho kev ntsuas ntawm cov kua dej tsis kam ntws. HPMC yog ib yam khoom ib nrab uas nws qhov kev ntsuas kuj nyob ntawm ntau yam, nrog rau qhov kub thiab txias. Txhawm rau kom nkag siab txog kev sib raug zoo ntawm viscosity thiab kub hauv HPMC, peb yuav tsum xub paub seb cov khoom tsim li cas thiab nws yog dab tsi.
HPMC yog muab los ntawm cellulose, ib txwm tshwm sim polymer nyob rau hauv cov nroj tsuag. Txhawm rau tsim HPMC, cellulose yuav tsum tau hloov kho tshuaj nrog propylene oxide thiab methyl chloride. Qhov kev hloov kho no ua rau tsim cov hydroxypropyl thiab methyl ether pawg hauv cov saw cellulose. Qhov tshwm sim yog ib qho khoom siv semi-tshuaj uas tuaj yeem yaj hauv dej thiab cov kuab tshuaj organic thiab siv ntau yam kev siv, nrog rau cov txheej txheem rau cov ntsiav tshuaj thiab ua cov thickening agent rau cov zaub mov, thiab lwm yam.
Lub viscosity ntawm HPMC nyob ntawm qhov concentration ntawm cov khoom thiab qhov kub ntawm qhov nws raug. Feem ntau, cov viscosity ntawm HPMC txo qis nrog nce concentration. Qhov no txhais tau hais tias ntau dua ntawm HPMC ua rau qis dua viscosities thiab rov ua dua.
Txawm li cas los xij, kev sib raug zoo ntawm viscosity thiab kub yog qhov nyuaj dua. Raws li tau hais ua ntej, viscosity ntawm HPMC nce nrog qhov kub thiab txias. Qhov no txhais tau hais tias thaum HPMC raug qhov kub thiab txias, nws lub peev xwm ntws qis thiab nws ua kom khov. Ib yam li ntawd, thaum HPMC raug kub siab, nws lub peev xwm ntws nce thiab nws cov viscosity txo.
Muaj ntau yam cuam tshuam rau kev sib raug zoo ntawm qhov kub thiab viscosity hauv HPMC. Piv txwv li, lwm cov kua uas muaj nyob hauv cov kua tuaj yeem cuam tshuam rau cov viscosity, xws li pH ntawm cov kua. Feem ntau, txawm li cas los xij, muaj kev sib cuam tshuam ntawm viscosity thiab qhov kub thiab txias hauv HPMC vim qhov cuam tshuam ntawm qhov kub thiab txias ntawm hydrogen bonding thiab molecular cuam tshuam ntawm cellulose chains hauv HPMC.
Thaum HPMC raug rau qhov kub thiab txias, cov cellulose chains ua nruj dua, uas ua rau muaj zog hydrogen bonding. Cov hydrogen bonds ua rau cov tshuaj tiv thaiv ntws, yog li ua rau nws viscosity. Hloov pauv, thaum HPMCs raug kub siab, cov cellulose chains tau hloov tau yooj yim dua, uas ua rau muaj tsawg dua hydrogen bonds. Qhov no txo cov tshuaj tiv thaiv kom ntws, ua rau qis viscosity.
Nws yog ib qho tsim nyog sau cia tias thaum feem ntau muaj kev sib cuam tshuam ntawm qhov viscosity thiab kub ntawm HPMC, qhov no tsis yog ib txwm muaj rau txhua hom HPMC. Qhov kev sib raug zoo ntawm viscosity thiab qhov kub thiab txias yuav txawv nyob ntawm cov txheej txheem tsim khoom thiab qib tshwj xeeb ntawm HPMC siv.
HPMC yog cov khoom siv ntau yam siv dav hauv ntau lub lag luam rau nws cov thickening thiab emulsifying zog. Lub viscosity ntawm HPMC nyob ntawm ntau yam, nrog rau cov concentration ntawm cov khoom thiab qhov kub ntawm qhov nws raug. Feem ntau, cov viscosity ntawm HPMC yog inversely proportional rau kub, uas txhais tau hais tias raws li qhov kub thiab txias, lub viscosity nce. Qhov no yog vim qhov tshwm sim ntawm qhov kub thiab txias ntawm hydrogen bonding thiab molecular kev cuam tshuam ntawm cellulose chains hauv HPMC.
Post lub sij hawm: Sep-08-2023