Hydroxyethyl methylcellulose yog dab tsi?

alias: hydroxyethyl methyl cellulose; hydroxyethyl methyl cellulose; hydroxymethyl ethyl cellulose; 2-hydroxyethyl methyl ether cellulose
Lus Askiv lub npe: Methylhydroxyethylcellulose; Cellulose; 2-hydroxyethyl methyl ether; HEMC; Tyopur MH[1]
Chemistry: Hydroymethylmethylcellulose;Hydroxyethylmethylcellulose; Hydroxymethylethyl cellulose.
CAS: 9032-42-2 Nr

Molecule: C2H6O2 xCH4O x PhEur 2002 txhais tau hais tias hydroxyethyl methylcellulose ua ib nrab O-methylated, ib nrab O-hydroxymethylated cellulose. Cov kev qhia tshwj xeeb sib txawv tau qhia los ntawm qhov pom tseeb viscosity tus nqi ntawm 2% w / v aqueous tov ntawm 20 ° C, thiab chav tsev yog mPa s.
Molecular Luj: PhEur 2002 txhais tau hais tias hydroxyethyl methylcellulose ua ib feem O-methylated, ib nrab O-hydroxymethylated cellulose. Cov kev qhia tshwj xeeb sib txawv tau qhia los ntawm qhov pom tseeb viscosity tus nqi ntawm 2% w / v aqueous tov ntawm 20 ° C, thiab chav tsev yog mPa s.

Cov yam ntxwv tseem ceeb ntawm hydroxyethyl methylcellulose (HEMC) yog:

1. Solubility: Soluble hauv dej thiab qee cov organic solvents. HEMC tuaj yeem yaj hauv dej txias. Nws qhov siab tshaj plaws concentration tsuas yog txiav txim siab los ntawm viscosity. Solubility sib txawv nrog viscosity. Qhov qis dua qhov viscosity, qhov ntau dua qhov solubility.

2. Ntsev tsis kam: HEMC cov khoom yog non-ionic cellulose ethers thiab tsis yog polyelectrolytes, yog li lawv muaj kev ruaj khov nyob rau hauv aqueous daws thaum hlau ntsev los yog organic electrolytes muaj, tab sis ntau ntxiv ntawm electrolytes yuav ua rau gelation thiab nag lossis daus.

3. Kev ua haujlwm saum npoo: Vim yog lub ntsej muag ua haujlwm ntawm cov tshuaj aqueous, nws tuaj yeem siv los ua cov tshuaj tiv thaiv colloidal, emulsifier thiab dispersant.

4. Thermal gel: Thaum HEMC cov khoom aqueous tov yog rhuab mus rau ib tug tej yam kub, nws yuav opaque, gels, thiab precipitates, tab sis thaum nws yog tsis tu ncua txias, nws rov qab mus rau lub qub tshuaj, thiab cov gel thiab nag los tshwm sim. Qhov kub yog nyob ntawm lawv cov roj nplua nyeem, ncua kev pab cuam, tiv thaiv colloids, emulsifiers, thiab lwm yam.

5. Metabolic inertness thiab tsis tshua muaj tsw thiab tsw: HEMC yog dav siv nyob rau hauv cov zaub mov thiab tshuaj vim hais tias nws yuav tsis metabolized thiab tsis muaj ntxhiab thiab tsw.

6. Mildew tsis kam: HEMC muaj cov kab mob mildew kuj zoo thiab zoo viscosity stability thaum lub sij hawm ntev cia.

7. PH stability: Lub viscosity ntawm aqueous tov ntawm HEMC cov khoom yog tsis tshua muaj kev cuam tshuam los ntawm acid los yog alkali, thiab pH tus nqi kuj tseem ruaj khov nyob rau hauv thaj tsam ntawm 3.0-11.0.
Daim ntawv thov: Hydroxyethyl methylcellulose tuaj yeem siv los ua tus neeg saib xyuas kev tiv thaiv colloidal, emulsifier thiab dispersant vim nws qhov chaw ua haujlwm hauv cov kua dej. Nws daim ntawv thov piv txwv yog raws li nram no: lub zog ntawm hydroxyethyl methylcellulose ntawm kev ua tau zoo ntawm cov cement. Hydroxyethyl methylcellulose yog ib qho tsis muaj ntxhiab, tsis qab, tsis muaj tshuaj lom cov hmoov dawb uas tuaj yeem yaj hauv dej txias los tsim cov kua nplaum pob tshab. Nws muaj cov yam ntxwv ntawm thickening, khi, dispersing, emulsifying, film-forming, suspending, adsorbing, gelling, nto active, tuav noo noo thiab tiv thaiv colloid. Txij li cov tshuaj aqueous muaj qhov ua haujlwm saum npoo av, nws tuaj yeem siv los ua tus neeg sawv cev tiv thaiv colloidal, emulsifier thiab dispersant. Hydroxyethyl methylcellulose aqueous tov muaj hydrophilicity zoo thiab yog cov dej tuav tus neeg sawv cev zoo.