HPMC, tseem hu ua hydroxypropyl methylcellulose, yog cov polymer uas yaj tau hauv dej uas siv dav hauv kev lag luam pleev kom zoo nkauj, tshuaj thiab khoom noj. Cov polymer no yog los ntawm cellulose, ib yam khoom ntuj uas pom muaj nyob hauv cov nroj tsuag. HPMC yog ib qho khoom ua kom tuab zoo heev uas siv dav los ua kom cov viscosity ntawm ntau yam kev daws teeb meem ntau ntxiv. Nws lub peev xwm los tsim cov gels thixotropic kuj ua rau nws yog ib qho kev xaiv nrov hauv ntau daim ntawv thov.
Cov khoom ntawm HPMC ua kom tuab
Cov yam ntxwv ua kom tuab ntawm HPMC paub zoo hauv kev lag luam. HPMC tuaj yeem ua rau kom cov kua nplaum nplaum los ntawm kev tsim cov gel network uas ntes cov dej molecules. Cov khoom me me ntawm HPMC tsim cov gel network thaum hydrated hauv dej thiab rub ib leeg los ntawm cov hydrogen bonds. Lub network tsim cov matrix peb-seem uas ua rau kom cov kua nplaum nplaum ntau ntxiv.
Ib qho ntawm cov txiaj ntsig tseem ceeb ntawm kev siv HPMC ua cov khoom ua kom tuab yog tias nws tuaj yeem ua rau cov tshuaj tuab yam tsis cuam tshuam rau nws qhov meej lossis xim. HPMC yog cov polymer tsis-ionic, uas txhais tau tias nws tsis muab cov nqi rau cov tshuaj. Qhov no ua rau nws zoo tagnrho rau kev siv hauv cov qauv meej lossis pob tshab.
Lwm qhov zoo ntawm HPMC yog tias nws tuaj yeem ua rau cov tshuaj tuab ntawm qhov tsis tshua muaj zog. Qhov no txhais tau tias tsuas yog xav tau me ntsis ntawm HPMC kom ua tiav qhov viscosity xav tau. Qhov no tuaj yeem txuag cov nqi rau cov chaw tsim khoom thiab muab cov neeg siv khoom nrog cov khoom lag luam pheej yig dua.
Thixotropy ntawm HPMC
Thixotropy yog lub cuab yeej ntawm cov khoom siv kom txo qis viscosity thaum raug kev ntxhov siab shear thiab rov qab mus rau nws qhov viscosity qub thaum kev ntxhov siab raug tshem tawm. HPMC yog cov khoom siv thixotropic, txhais tau tias nws kis tau lossis nchuav tau yooj yim hauv qab kev ntxhov siab shear. Txawm li cas los xij, thaum kev ntxhov siab raug tshem tawm, nws rov qab mus rau qhov nplaum thiab tuab dua.
Cov khoom thixotropic ntawm HPMC ua rau nws zoo tagnrho rau ntau daim ntawv thov. Piv txwv li, nws feem ntau siv rau hauv cov xim pleev xim, ua ib txheej tuab ntawm ib qho chaw. Cov khoom thixotropic ntawm HPMC ua kom ntseeg tau tias cov txheej tseem nyob ntawm qhov chaw yam tsis muaj sagging lossis khiav. HPMC kuj tseem siv rau hauv kev lag luam zaub mov ua ib qho thickener rau cov kua ntses thiab cov khaub ncaws hnav. Cov khoom thixotropic ntawm HPMC ua kom ntseeg tau tias cov kua ntses lossis cov khaub ncaws hnav tsis ntws los ntawm cov diav lossis cov phaj, tab sis hloov chaw tseem tuab thiab sib xws.
HPMC yog ib qho polymer uas siv tau ntau yam hauv ntau yam lag luam. Nws cov khoom ua kom tuab thiab thixotropic ua rau nws zoo tagnrho rau kev ua kom zoo nkauj, tshuaj thiab cov khoom noj. HPMC yog ib qho thickener zoo heev, ua rau cov kua nplaum tsis muaj kev cuam tshuam rau nws qhov meej lossis xim. Nws cov khoom thixotropic ua kom cov kua nplaum tsis tuab dhau lossis nyias dhau, nyob ntawm seb daim ntawv thov. HPMC yog ib qho khoom xyaw tseem ceeb hauv ntau yam khoom, thiab nws cov txiaj ntsig ntau ua rau nws yog qhov kev xaiv nrov rau cov chaw tsim khoom thiab cov neeg siv khoom.
Lub sijhawm tshaj tawm: Lub Yim Hli-25-2023