Boleng ba Hydroxypropyl Methyl Cellulose

Hydroxypropyl methylcellulose e hloekisoa ho tloha k'hothone ka mor'a alkalization, e sebelisa propylene oxide le methyl chloride e le li-etherification agents, 'me e etsa letoto la liketso ho hlahisa ether e se nang ionic cellulose. Hydroxypropyl methylcellulose ke non-ionic cellulose ether, e tšoeu ka chebahalo, ha e na monko ebile ha e latsoehe. Tekanyo ea ho nka sebaka ka kakaretso ke . Thepa ea eona e fapana ho latela karolelano ea methoxyl ho hydroxypropyl content.

Taba ea pele, sheba pele motsoako oa hydroxypropyl methylcellulose:

Selulose e hloekisitsoeng ea k'hothone e tšoaroa ka tharollo ea alkali ho 35-40 ° C bakeng sa halofo ea hora, e hatelloa, 'me selulose e silafatsoa ka 35 ° C le ho tsofala hantle, e le hore tekanyo e tloaelehileng ea polymerization ea fiber e fumanoeng ea alkali e ka hare ho sebaka se hlokahalang. Kenya fiber ea alkali ka har'a tanka ea etherification, eketsa propylene oxide le methyl chloride ka tatellano, etherify ho 50-80 ° C bakeng sa lihora tse 5, 'me khatello e phahameng ke hoo e ka bang. Ebe u eketsa tekanyo e loketseng ea hydrochloric acid le oxalic acid metsing a chesang a 90 ° C ho atolosa molumo. Dehydrate ka centrifuge. Ha mongobo oa thepa o le tlase ho 60%, o hlatsoe ho se nke lehlakore, ebe o o omisa ka tlase ho 5% ka phallo ea moea o chesang ka 130 ° C. Qetellong o ile oa pshatla ka sefe ea 20-mesh ho fumana sehlahisoa se felileng.

Likarolo tsa Sehlahisoa sa Hydroxypropyl Methyl Cellulose:

1. Hydroxypropyl methylcellulose e qhibiliha habonolo metsing a batang 'me e tla qhibiliha metsing a chesang. Leha ho le joalo, mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methylcellulose. Ho qhibiliha ka metsing a batang ho boetse ho ntlafala haholo ho feta methyl cellulose.

2. The viscosity ea hydroxypropyl methylcellulose e amana le boima ba molek'hule, 'me viscosity e phahame ha boima ba molek'hule bo le boholo. Mocheso o boetse o ama viscosity ea eona, ha mocheso o ntse o eketseha, viscosity e fokotseha. Empa viscosity ea eona e phahameng e tlase ho feta methyl cellulose. Tharollo ea eona e tsitsitse mocheso oa kamore.

Bokhoni ba ho boloka metsi ba hydroxypropyl methylcellulose bo ipapisitse le palo ea eona ea tlatsetso, viscosity, joalo-joalo, mme sekhahla sa eona sa ho boloka metsi se phahame ho feta sa methyl cellulose.

3. Hydroxypropyl methylcellulose e tsitsitse ho acid le alkali, 'me tharollo ea eona ea metsi e tsitsitse ka har'a pH = 2-12. Soda ea Caustic le metsi a lime ha li na phello e fokolang ho thepa ea eona, empa alkali e ka potlakisa ho qhibiliha ha eona 'me ea eketsa viscosity ea eona hanyenyane. Hydroxypropyl methylcellulose e tsitsitse ho matsoai a tloaelehileng, empa ha motsoako oa motsoako oa letsoai o phahame, viscosity ea tharollo ea hydroxypropyl methylcellulose e atisa ho eketseha.

4. Hydroxypropyl methylcellulose e ka kopanngoa le li-polymers tse qhibilihisang metsi ho etsa setlolo se lekaneng, se nang le viscosity e phahameng. Joalo ka joala ba polyvinyl, ether ea phofo ea metsi a letša, boka ba meroho, jj.

Hydroxypropyl methylcellulose e na le khanyetso e ntle ea enzyme ho feta methylcellulose, 'me tharollo ea eona ha e na monyetla oa ho senyeha ka mokhoa oa enzymatic ho feta methylcellulose.

5. Ho khomarela pakeng tsa hydroxypropyl methylcellulose le sebopeho sa seretse se phahameng ho feta sa methylcellulose.

Seretse se kopantseng metsi ke samente, kakaretso e ntle, li-additives le metsi, 'me likarolo tse fapaneng li khethoa ho latela ts'ebetso. Ka mor'a hore motsoako o lekanyetsoe 'me o kopane ka tekanyo e itseng setsing sa ho kopanya, motsoako o isoa sebakeng sa ho sebelisoa ke teraka e kopanyang ebe o bolokoa ka sejaneng se khethehileng,' me motsoako o metsi o sebelisoa ka nako e behiloeng.

Joang ho ahlola boleng ba hydroxypropyl methylcellulose?

Ho ahlola boleng ba hydroxypropyl methylcellulose haholo-holo ho ipapisitse le matšoao a mabeli, e 'ngoe ke degree of substitution (DS) mme e' ngoe ke bohloeki. Ka kakaretso, thepa ea carboxymethyl cellulose e fapane haeba tekanyo ea ho fetola e fapane; ho phahama ha tekanyo ea ho fetola, ho matlafala ha solubility, le ho ntlafatsa pepeneneng le botsitso ba tharollo. Ho latela litlaleho tse amehang, pepeneneng ea carboxymethyl cellulose e batla e le ntle ha tekanyo ea phetisetso e le ~, 'me viscosity ea tharollo ea eona e nang le metsi e phahame ha pH ea boleng e le 6-9. Ka mantsoe a mang, ho lekanya boleng ba carboxymethyl cellulose, hoa hlokahala ho ba le kutloisiso e ntle ea tekanyo ea eona ea ho fetola le ho hloeka. Matšoao ana a mabeli a finyella litlhoko, ho bolelang hore boleng ba eona bo botle haholo.