Kodi hydroxypropyl methyl cellulose ndi hydroxyethyl cellulose ndi chiyani?

1.Hydroxypropyl methyl cellulose

Hydroxypropyl methylcellulosendi mitundu ya cellulose yomwe kutulutsa kwake ndikugwiritsa ntchito kukuchulukirachulukira. Ndi cellulose yopanda ionic yosakaniza ether yopangidwa kuchokera ku thonje woyengedwa pambuyo pa alkalization, pogwiritsa ntchito propylene oxide ndi methyl chloride monga etherification agent, kupyolera muzotsatira zingapo. Mlingo wolowa m'malo nthawi zambiri ndi 1.2 ~ 2.0. Katundu wake amasiyana malinga ndi kuchuluka kwa methoxyl zomwe zili ndi hydroxypropyl.

(1) Hydroxypropyl methylcellulose imasungunuka mosavuta m'madzi ozizira, ndipo imakumana ndi zovuta pakusungunuka m'madzi otentha. Koma kutentha kwake kwa gelation m'madzi otentha ndikokwera kwambiri kuposa kwa methyl cellulose. Kusungunuka m'madzi ozizira kumakhalanso bwino kwambiri poyerekeza ndi methyl cellulose.

(2) (2) The viscosity ya hydroxypropyl methylcellulose imagwirizana ndi kulemera kwake kwa maselo, ndipo kukula kwake kwa molekyulu, kumapangitsanso kukhuthala. Kutentha kumakhudzanso kukhuthala kwake, pamene kutentha kumawonjezeka, kukhuthala kumachepa. Komabe, chikoka cha mamasukidwe ake apamwamba komanso kutentha kwake kumakhala kotsika kuposa kwa methyl cellulose. Yankho lake ndi lokhazikika likasungidwa kutentha.

(3) Kusungidwa kwa madzi kwa hydroxypropyl methylcellulose kumadalira kuchuluka kwake, kukhuthala kwake, ndi zina zambiri, ndipo kuchuluka kwake komwe kumasungira madzi pansi pa kuchuluka komweko ndikokwera kuposa kwa methyl cellulose.

(4) Hydroxypropyl methylcellulose ndi yokhazikika ku asidi ndi alkali, ndipo njira yake yamadzimadzi imakhala yokhazikika pa pH = 2 ~ 12. Madzi a caustic ndi laimu sakhala ndi zotsatira zochepa pa ntchito yake, koma alkali amatha kufulumizitsa kusungunuka kwake ndikuwonjezera kukhuthala kwake pang'ono. Hydroxypropyl methylcellulose ndi yokhazikika ku mchere wamba, koma pamene mchere wa mchere uli wambiri, kukhuthala kwa hydroxypropyl methylcellulose solution kumawonjezeka.

(5) Hydroxypropyl methylcellulose ikhoza kusakanikirana ndi ma polima osungunuka ndi madzi kuti apange njira yofanana, yapamwamba-makamaka. Monga polyvinyl mowa, wowuma ether, masamba chingamu, etc.

(6) Hydroxypropyl methylcellulose imakhala ndi kukana bwino kwa enzyme kuposa methylcellulose, ndipo yankho lake silingawonongeke ndi michere kuposa methylcellulose.

(7) Kumamatira kwa hydroxypropyl methylcellulose kumapangidwe amatope ndikokwera kuposa methylcellulose.

2. Ma cellulose a Hydroxyethyl

Amapangidwa kuchokera ku thonje loyengedwa lopangidwa ndi alkali, ndipo amachita ndi ethylene oxide ngati etherification agent pamaso pa isopropanol. Madigiri ake olowa m'malo nthawi zambiri amakhala 1.5 ~ 2.0. Ili ndi hydrophilicity yamphamvu ndipo ndiyosavuta kuyamwa chinyezi.

(1) Hydroxyethyl cellulose imasungunuka m'madzi ozizira, koma ndizovuta kusungunuka m'madzi otentha. Yankho lake ndi khola pa kutentha popanda gelling. Ikhoza kugwiritsidwa ntchito kwa nthawi yaitali pansi pa kutentha kwakukulu mumatope, koma kusungirako madzi kumakhala kochepa kusiyana ndi methyl cellulose.

(2)Hydroxyethyl cellulosendi okhazikika kwa asidi ambiri ndi zamchere, ndi zamchere akhoza imathandizira kuvunda ndi pang'ono kuonjezera mamasukidwe akayendedwe ake. Kuwonongeka kwake m'madzi kumakhala koyipa pang'ono kuposa methyl cellulose ndi hydroxypropyl methyl cellulose.

(3) Ma cellulose a Hydroxyethyl ali ndi ntchito yabwino yotsutsa-sag pamatope, koma amakhala ndi nthawi yayitali yochepetsera simenti.

(4) Kuchita kwa hydroxyethyl cellulose yopangidwa ndi mabizinesi am'nyumba mwachiwonekere ndi yotsika kuposa ya methyl cellulose chifukwa chokhala ndi madzi ambiri komanso phulusa lalitali.

(5) Kutentha kwa madzi a hydroxyethyl cellulose ndizovuta kwambiri. Pa kutentha pafupifupi 40 ° C, mildew imatha kuchitika mkati mwa masiku atatu mpaka 5, zomwe zingakhudze ntchito yake.