IHydroxyethyl methyl I-Cellulose

I-Cellulose ether iyisisetshenziswa samakhemikhali e-polymer esihle esetshenziswa kabanzi eyenziwe nge-polymer cellulose yemvelo ngokwelashwa ngamakhemikhali. Ngemva kokukhiqizwa kwe-cellulose nitrate ne-cellulose acetate ekhulwini le-19, osokhemisi baye basungula uchungechunge lokuphuma kwe-cellulose kwama-cellulose ethers amaningi, futhi izinkambu ezintsha zokufaka isicelo ziye zatholwa ngokuqhubekayo, ezibandakanya imikhakha eminingi yezimboni. Imikhiqizo ye-cellulose ether efana ne-sodium carboxymethyl cellulose (CMC), i-ethyl cellulose (EC), i-hydroxyethyl cellulose (HEC), i-hydroxypropyl cellulose (HPC), i-methyl hydroxyethyl cellulose (MHEC) kanye ne-methyl hydroxypropyl cellulose (MHPC) namanye ama-cellulose ethers aziwa ngokuthi "i-industrial monosodium glutamate" futhi isetshenziswe kabanzi ekubholeni amafutha, ukwakha, ukumboza, ukudla, imithi kanye namakhemikhali nsuku zonke.

I-Hydroxyethyl methylcellulose(MHEC) iyimpushana emhlophe engenaphunga, enganambitheki, engenabuthi engancibilika emanzini abandayo ukuze yakhe isixazululo se-viscous esisobala. Inezici zokuqina, ukubopha, ukusabalalisa, i-emulsifying, ukwenza ifilimu, ukumisa okwesikhashana, i-adsorbing, i-gelling, i-surface esebenzayo, ukugcina umswakama nokuvikela i-colloid. Ngenxa yomsebenzi osebenzayo wesisombululo se-aqueous, ingasetshenziswa njenge-ejenti yokuzivikela ye-colloidal, i-emulsifier ne-dispersant. Isixazululo samanzi se-Hydroxyethyl methylcellulose sine-hydrophilicity enhle futhi iyi-ejenti esebenza kahle yokugcina amanzi. Ngenxa yokuthi i-hydroxyethyl methylcellulose iqukethe amaqembu e-hydroxyethyl, inekhono elihle lokunqanda isikhutha, ukuzinza okuhle kwe-viscosity kanye nokumelana nesikhutha ngesikhathi sokugcina isikhathi eside.

I-Hydroxyethyl methylcellulose (HEMC) ilungiswa ngokwethula izingxenye ze-ethylene oxide (MS 0.3~0.4) ku-methylcellulose (MC), futhi ukumelana nosawoti wayo kungcono kunama-polymers angashintshiwe. Izinga lokushisa le-gelation le-methylcellulose nalo liphakeme kunalelo le-MC.

Isakhiwo:

Isici:

Izici eziyinhloko ze-hydroxyethyl methylcellulose (HEMC) yilezi:

1. I-Solubility: Incibilika emanzini nakwezinye izincibilikisi eziphilayo. I-HEMC ingancibilika emanzini abandayo. Ukugxila kwayo okuphezulu kunqunywa kuphela yi-viscosity. I-Solubility iyahlukahluka ngokuya nge-viscosity. I-viscosity ephansi, i-solubility enkulu.
2. Ukumelana nosawoti: Imikhiqizo ye-HEMC i-non-ionic cellulose ethers futhi ayiwona ama-polyelectrolyte, ngakho-ke azinzile kuzixazululo ezinamanzi lapho usawoti wensimbi noma ama-electrolyte ephilayo ekhona, kodwa ukwengezwa ngokweqile kwama-electrolyte kungabangela i-gelation kanye nemvula.
3. Umsebenzi ongaphezulu: Ngenxa yomsebenzi osebenzayo ongaphezulu wesisombululo esinamanzi, singasetshenziswa njenge-ejenti yokuvikela ye-colloidal, i-emulsifier ne-dispersant.
4. Ijeli elishisayo: Uma isixazululo samanzi semikhiqizo ye-HEMC sishiselwa ekushiseni okuthile, siba yi-opaque, ama-gel, kanye nemvula, kodwa lapho sipholile ngokuqhubekayo, sibuyela esimweni sokuqala sesisombululo, kanye nezinga lokushisa lapho leli jeli kanye nemvula. kwenzeka ikakhulukazi Ngokuya kubo izinto zokugcoba, izinsiza ezimisiwe, ama-colloid okuzivikela, ama-emulsifiers njll.
5. I-Metabolism inert kanye nephunga eliphansi kanye nephunga: I-HEMC isetshenziswa kakhulu ekudleni nasemthini ngoba ngeke isetshenziswe futhi inephunga eliphansi kanye nephunga elimnandi.
6. Ukumelana nesikhunta: I-HEMC inokumelana okuhle nesikhutha kanye nokuzinza okuhle kwe-viscosity ngesikhathi sokugcina isikhathi eside.
7. Ukuzinza kwe-PH: I-viscosity yesisombululo esinamanzi semikhiqizo ye-HEMC ayithinteki neze i-asidi noma i-alkali, futhi inani le-pH lizinzile ngokuqhathaniswa phakathi kwebanga lika-3.0 kuya ku-11.0.

Isicelo:

IHydroxyethyl methylcellulose ingasetshenziswa njenge-ejenti evikelayo ye-colloidal, i-emulsifier kanye ne-dispersant ngenxa yomsebenzi wayo osebenza phezulu kusisombululo esinamanzi. Izibonelo zokusetshenziswa kwayo zimi kanje:

1. Umphumela we-hydroxyethyl methylcellulose ekusebenzeni kukasimende. IHydroxyethyl methylcellulose iyimpushana emhlophe engenaphunga, enganambitheki, engenabuthi engancibilika emanzini abandayo ukuze yakhe isixazululo se-viscous esisobala. Inezici zokuqina, ukubopha, ukusabalalisa, i-emulsifying, ukwenza ifilimu, ukumisa okwesikhashana, i-adsorbing, i-gelling, i-surface esebenzayo, ukugcina umswakama nokuvikela i-colloid. Njengoba isixazululo esinamanzi sinomsebenzi osebenzayo, singasetshenziswa njenge-ejenti yokuzivikela ye-colloidal, i-emulsifier ne-dispersant. Isixazululo samanzi se-Hydroxyethyl methylcellulose sine-hydrophilicity enhle futhi iyi-ejenti esebenza kahle yokugcina amanzi.
2. Upende wokusiza onokuguquguquka okuphezulu ulungiswa, owenziwe ngezinto zokusetshenziswa ezilandelayo ezingxenyeni ngesisindo: 150-200 g wamanzi deionized; 60-70 g we-emulsion ehlanzekile ye-acrylic; 550-650 g we-calcium enzima; 70-90 g we-talcum powder; 30-40g base cellulose isixazululo aqueous; 10-20g isixazululo samanzi se-lignocellulose; 4-6g ifilimu yokwenza ifilimu; 1.5-2.5g isinqamuleli kanye bactericide; 1.8-2.2g dispersant; 3.5-4.5g; i-ethylene glycol 9-11g; Isixazululo samanzi se-hydroxyethyl methylcellulose senziwa ngokuncibilikisa i-2-4% ye-hydroxyethyl methylcellulose emanzini; Isixazululo samanzi se-lignocellulose senziwe nge-1-3 % I-Lignocellulose yenziwa ngokuncibilika emanzini.

Ukulungiselela:

Indlela yokulungiselela i-hydroxyethyl methylcellulose, indlela yokusebenzisa ukotini ocolisisiwe njengempahla eluhlaza kanye ne-ethylene oxide njenge-etherification ejenti yokulungisa i-hydroxyethyl methylcellulose. Izingxenye zesisindo zezinto zokusetshenziswa zokulungiselela i-hydroxyethyl methyl cellulose zimi kanje: izingxenye ezingama-700-800 ze-toluene nengxube ye-isopropanol njenge-solvent, izingxenye ezingama-30-40 zamanzi, izingxenye ezingama-70-80 ze-sodium hydroxide, izingxenye ezingama-80-85 zikakotini ocwengekile, indandatho 20-28 izingxenye oxyethane, 80-90 izingxenye methyl chloride, 16-19 izingxenye glacial acetic acid; izinyathelo eziqondile yilezi:

Isinyathelo sokuqala, ku-kettle yokusabela, engeza ingxube ye-toluene ne-isopropanol, amanzi, ne-sodium hydroxide, ukushisa kufika ku-60-80 ° C, hlala ufudumele imizuzu engu-20-40;

Isinyathelo sesibili, i-alkalization: pholisa izinto ezingenhla zibe ku-30-50°C, engeza ukotini ocolisisiwe, fafaza i-toluene ne-isopropanol ingxube encibilikisayo, uyipompa iye ku-0.006Mpa, ugcwalise i-nitrogen ngokushintshanisa oku-3, futhi wenze ngemva kokufaka esikhundleni se-Alkalinization, izimo ze-alkalization yilezi: isikhathi se-alkalization amahora angu-2, futhi izinga lokushisa le-alkalization lingu-30 ° C kuya ku-50 ° C;

Isinyathelo sesithathu, i-etherification: ngemva kokuqedwa kwe-alkalization, i-reactor ikhishwa ku-0.05-0.07MPa, futhi i-ethylene oxide ne-methyl chloride yengezwe imizuzu engu-30-50; isigaba sokuqala se-etherification: 40-60 ° C, 1.0-2.0 Amahora, ingcindezi ilawulwa phakathi kuka-0.15 no-0.3Mpa; isigaba sesibili se-etherification: 60～90℃, 2.0～2.5 amahora, ingcindezi ilawulwa phakathi kuka-0.4 no-0.8Mpa;

Isinyathelo sesine, ukungathathi hlangothi: Faka i-glacial acetic acid elinganisiwe kusengaphambili eketelani lemvula, cindezela ku-etherified material ukuze ungabi nalutho, nyusa izinga lokushisa libe ku-75-80°C ukuze kunemvula, izinga lokushisa likhuphukela ku-102°C, kanye ne-pH. inani liyi-6 Ngehora lesi-8, ukuchithwa kwe-desolventization kuqediwe; ithangi le-desolventization ligcwele amanzi kampompi aphathwe idivayisi ye-osmosis e-90 ° C kuya ku-100 ° C;

Isinyathelo sesihlanu, ukugeza kwe-centrifugal: into esiteji sesine i-centrifuged ngokusebenzisa i-screw centrifuge enezingqimba, futhi impahla ehlukanisiwe idluliselwa ku-tank yokugeza egcwele amanzi ashisayo kusengaphambili ukuze kugezwe impahla;

Isinyathelo sesithupha, ukomiswa kwe-centrifugal: izinto eziwashiwe zidluliselwa esomisini nge-screw centrifuge enezingqimba, futhi izinto zomisiwe zomiswe ku-150-170 ° C, futhi izinto ezomile ziyachotshozwa futhi zihlanganiswe.

Uma kuqhathaniswa nobuchwepheshe obukhona bokukhiqiza i-cellulose ether, ukusungulwa kwamanje kusebenzisa i-ethylene oxide njenge-etherification agent ukuze kulungiswe i-hydroxyethyl methyl cellulose, enekhono elihle lokulwa nesikhunta ngenxa yokuqukatha amaqembu e-hydroxyethyl. Inokuqina okuhle kwe-viscosity kanye nokumelana nesikhutha ngesikhathi sokugcina isikhathi eside. Ingasetshenziswa esikhundleni sama-cellulose ethers.