Vim li cas HEMC yog qhov kev xaiv zoo dua li HPMC?

Hypromellose (HPMC) thiab hydroxyethylmethylcellulose (HEMC) yog ob qho kev siv cellulose derivatives nrog rau kev siv hauv kev lag luam tshuaj, zaub mov thiab tshuaj pleev ib ce. Txawm hais tias HPMC thiab HEMC sib koom ntau qhov sib xws, lawv txawv ntawm qee txoj hauv kev, ua rau ib qho zoo tshaj rau lwm yam rau qee yam kev siv.

HEMC yog hloov kho cellulose ether tau los ntawm reacting methyl cellulose nrog ethylene oxide thiab ethyl chloride, thiab ces hloov ethyl rau hydroxyl. Yog li, HEMC muaj qib siab ntawm kev hloov pauv (DS) dua li HPMC. DS hais txog qhov nruab nrab ntawm cov neeg hloov pauv hauv ib chav tsev piam thaj, uas cuam tshuam rau lub cev thiab tshuaj lom neeg ntawm polymer. Feem ntau, DS siab dua ua rau muaj kev ua kom zoo dua hauv cov kuab tshuaj organic, qhov kev sib cais sai dua, thiab muaj zog ntxiv kom nqus dej. DS ntawm HEMC feem ntau yog 1.7-2.0, thaum DS ntawm HPMC feem ntau yog nyob nruab nrab ntawm 1.2 thiab 1.5.

Ib qho txiaj ntsig zoo ntawm HEMC tshaj HPMC yog nws lub peev xwm khaws dej zoo heev, ua rau nws zoo tagnrho rau cov ntawv nplaum, cov khoom siv thiab lwm yam khoom uas yuav tsum tau khaws cov dej zoo. HEMC kuj tseem tiv taus cov kab mob microbial ntau dua li HPMC thiab muaj lub neej txee ntev dua. Qhov nce hydrophobicity ntawm HEMC thiab muaj cov pab pawg ethyl nyob rau hauv nws cov caj qaum ua rau nws yog ib qho zoo heev emulsifier thiab tuaj yeem txhim kho lub sijhawm ntev ntawm emulsions.

Lwm qhov txiaj ntsig ntawm kev siv HEMC yog nws txoj kev sib raug zoo nrog rau feem ntau lwm yam tshuaj, uas ua rau nws muaj peev xwm ua tau zoo hauv ntau daim ntawv thov. Tsis tas li ntawd, HEMC muaj cov cuab yeej ua yeeb yaj kiab zoo, uas ua rau nws muaj txiaj ntsig zoo rau kev tsim cov coatings thiab binders hauv kev tsim cov ntsiav tshuaj, tshuaj thiab granules.

Ntawm qhov tod tes, HPMC muaj cov khoom siv thermal gelling zoo dua, uas ua rau nws yog qhov kev xaiv zoo tshaj plaws rau kev tso tshuaj qeeb qeeb uas xav tau cov gels kub-rhiab. HPMC kuj muaj cov dej solubility zoo dua thiab tsis tshua muaj kev tsim coagglomerates, uas yog insoluble aggregates ntawm polymers hauv kev daws.

Hauv kev xaus, ob qho tib si HEMC thiab HPMC yog cov txiaj ntsig ntawm cellulose derivatives uas muaj qhov zoo sib txawv nyob ntawm daim ntawv thov. HEMC muaj cov dej tuav zoo dua, emulsification, thiab kev sib raug zoo nrog lwm cov tshuaj, thaum HPMC muaj cov khoom siv thermogelling zoo thiab dej solubility. Yog li, kev xaiv ntawm HEMC thiab HPMC nyob ntawm qhov xav tau daim ntawv thov, txheej txheem tsim khoom thiab cov khoom siv kawg.