Hydroxyethyl Methyl Cellulose

Cellulose ether ke sesebelisoa sa lik'hemik'hale se sebelisoang haholo sa polymer se entsoeng ka selulose ea tlhaho ea polymer ka kalafo ea lik'hemik'hale. Kamora ho etsoa ha cellulose nitrate le cellulose acetate lekholong la bo19 la lilemo, litsebi tsa k'hemistri li thehile letoto la li-cellulose tse nkiloeng ho li-cellulose ethers tse ngata, 'me masimo a macha a ts'ebeliso a 'nile a sibolloa khafetsa, a kenyelletsang mafapha a mangata a indasteri. Lihlahisoa tsa cellulose ether tse kang sodium carboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methyl hydroxyethyl cellulose (MHEC) le methyl hydroxypropyl cellulose (MHPC) le tse ling tsa cellulose ethers li tsejoa e le "industrial monosodium glutamate" 'me e sebelisitsoe haholo ho cheka oli, ho haha, ho roala, lijo, meriana le lik'hemik'hale tsa letsatsi le letsatsi.

Hydroxyethyl methylcellulose(MHEC) ke phofo e tšoeu e se nang monko, e se nang chefo, e se nang chefo e ka qhibilihang metsing a batang ho etsa tharollo e hlakileng ea viscous. E na le litšoaneleho tsa ho teteana, ho tlama, ho qhalakanya, emulsifying, filimi-forming, suspending, adsorbing, gelling, surface active, ho boloka mongobo le ho sireletsa colloid. Ka lebaka la ts'ebetso e sebetsang ea holim'a metsi a metsi, e ka sebelisoa e le moemeli oa tšireletso ea colloidal, emulsifier le dispersant. Hydroxyethyl methylcellulose aqueous solution e na le hydrophilicity e ntle mme ke sesebelisoa se sebetsang sa ho boloka metsi. Hobane hydroxyethyl methylcellulose e na le lihlopha tsa hydroxyethyl, e na le bokhoni bo botle ba ho thibela hlobo, botsitso bo botle ba viscosity le ho hanyetsa hlobo nakong ea polokelo ea nako e telele.

Hydroxyethyl methylcellulose (HEMC) e lokiselitsoe ka ho hlahisa li-substituents tsa ethylene oxide (MS 0.3 ~ 0.4) ho methylcellulose (MC), 'me ho hanyetsa ha eona letsoai ho molemo ho feta ho li-polymers tse sa fetoloang. Mocheso oa mocheso oa methylcellulose o boetse o phahame ho feta oa MC.

Sebopeho:

Sebopeho:

Litšobotsi tsa mantlha tsa hydroxyethyl methylcellulose (HEMC) ke:

1. Solubility: Ho qhibiliha ka metsing le lihlapolli tse ling tsa tlhaho. HEMC e ka qhibiliha ka metsing a batang. Boemo ba eona bo phahameng ka ho fetisisa bo khethoa feela ke viscosity. Sollubility e fapana ho ea ka viscosity. The viscosity e ka tlaase, e kholoanyane ea ho qhibiliha.
2. Ho hanyetsa letsoai: Lihlahisoa tsa HEMC ha li na ionic cellulose ethers 'me ha li polyelectrolyte, kahoo li batla li tsitsitse ka tharollo ea metsi ha letsoai la tšepe kapa li-electrolyte tsa tlhaho li le teng, empa ho eketsoa ho feteletseng ha li-electrolyte ho ka baka gelation le pula.
3. Mosebetsi o ka holimo: Ka lebaka la ts'ebetso e sebetsang ea holim'a metsi a metsi, e ka sebelisoa e le moemeli oa tšireletso ea colloidal, emulsifier le dispersant.
4. Thermal gel: Ha tharollo ea metsi ea lihlahisoa tsa HEMC e futhumetse mocheso o itseng, e fetoha opaque, gel, le precipitates, empa ha e ntse e pholile, e khutlela sebakeng sa pele sa tharollo, le mocheso oo gel ena le pula e nang le eona. etsahalang ke haholo-holo Ho itšetlehile ka bona lubricants, suspending lithuso, colloids sireletsang, emulsifiers joalo-joalo.
5. Metabolism inert le monko o fokolang le monko o monate: HEMC e sebelisoa haholo lijong le meriana hobane e ke ke ea e-ba le metabolized mme e na le monko o fokolang le monko o monate.
6. Ho hanyetsa hlobo: HEMC e na le khanyetso e ntle ea hlobo le botsitso bo botle ba viscosity nakong ea polokelo ea nako e telele.
7. PH botsitso: The viscosity ea tharollo e nang le metsi a lihlahisoa tsa HEMC ha e amehe haholo ke acid kapa alkali, 'me boleng ba pH bo batla bo tsitsitse ka har'a mefuta ea 3.0 ho ea ho 11.0.

Kopo:

Hydroxyethyl methylcellulose e ka sebelisoa e le moemeli oa tšireletso ea colloidal, emulsifier le dispersant ka lebaka la ts'ebetso ea eona e sebetsang ka holim'a metsi ka tharollo ea metsi. Mehlala ea tšebeliso ea eona ke e latelang:

1. Phello ea hydroxyethyl methylcellulose ts'ebetsong ea samente. Hydroxyethyl methylcellulose ke phofo e tšoeu e sa nkheng, e sa latsoeheng, e se nang chefo e ka qhalloang metsing a batang ho etsa tharollo e hlakileng ea viscous. E na le litšoaneleho tsa ho teteana, ho tlama, ho qhalakanya, emulsifying, filimi-forming, suspending, adsorbing, gelling, surface active, ho boloka mongobo le ho sireletsa colloid. Kaha tharollo ea metsi e na le bokaholimo bo sebetsang, e ka sebelisoa e le moemeli oa tšireletso ea colloidal, emulsifier le dispersant. Hydroxyethyl methylcellulose aqueous solution e na le hydrophilicity e ntle mme ke sesebelisoa se sebetsang sa ho boloka metsi.
2. Pente ea liphallelo e nang le phetoho e phahameng e lokiselitsoe, e entsoeng ka lisebelisoa tse latelang tse tala likarolong ka boima ba 'mele: 150-200 g ea metsi a deionized; 60-70 g ea emulsion e hloekileng ea acrylic; 550-650 g ea k'halsiamo e boima; 70-90 g ea phofo ea talcum; 30-40g base cellulose aqueous tharollo; 10-20g lignocellulose tharollo ea metsi; 4-6g thuso ea ho etsa filimi; 1.5-2.5g sebolaya dikokwana-hloko le bactericide; 1.8-2.2g dispersant; 3.5-4.5g; Ethylene glycol 9-11g; Tharollo ea metsi a hydroxyethyl methylcellulose e entsoe ka ho qhibiliha 2-4% hydroxyethyl methylcellulose metsing; Tharollo ea metsi a lignocellulose e entsoe ka 1-3% Lignocellulose e entsoe ka ho qhibiliha ka metsing.

Boitokisetso:

Mokhoa oa ho itokisa oa hydroxyethyl methylcellulose, mokhoa ona ke ho sebelisa k'hothone e hloekisitsoeng e le thepa e tala le ethylene oxide e le moemeli oa etherification ho lokisa hydroxyethyl methylcellulose. Likarolo tsa boima ba lisebelisoa tse tala bakeng sa ho lokisa hydroxyethyl methyl cellulose ke tse latelang: likarolo tse 700-800 tsa toluene le isopropanol e le solvent, likarolo tse 30-40 tsa metsi, likarolo tse 70-80 tsa sodium hydroxide, likarolo tse 80-85 tsa k'hothone e hloekisitsoeng, selikalikoe sa 20-28 likarolo tsa oxyethane, likarolo tse 80-90 tsa methyl chloride, likarolo tse 16-19 tsa glacial acetic acid; mehato e khethehileng ke:

Mohato oa pele, ka kettle e arabelang, eketsa toluene le motsoako oa isopropanol, metsi, le sodium hydroxide, mocheso ho fihlela ho 60-80 ° C, o futhumale ka metsotso e 20-40;

Mohato oa bobeli, alkalization: pholisa lisebelisoa tse kaholimo ho 30-50 ° C, eketsa k'hothone e hloekisitsoeng, fafatsa toluene le isopropanol motsoako oa motsoako, o e pompe ho 0.006Mpa, tlatsa naetrojene bakeng sa tse ling tse 3, 'me u e etse kamora ho khutlisa Alkalinization. maemo a alkalization ke: nako ea alkalization ke lihora tse 2, 'me mocheso oa alkalization ke 30 ° C ho 50 ° C;

Mohato oa boraro, etherification: ka mor'a hore alkalization e phethoe, mochine o tlosoa ho 0.05-0.07MPa, 'me ethylene oxide le methyl chloride li eketsoa ka metsotso e 30-50; mohato oa pele oa etherification: 40-60 ° C, 1.0-2.0 Lihora, khatello e laoloa pakeng tsa 0.15 le 0.3Mpa; mohato oa bobeli oa etherification: 60～90℃, 2.0～2.5 lihora, khatello e laoloa pakeng tsa 0.4 le 0.8Mpa;

Mohato oa bone, ho se nke lehlakore: Kenya glacial acetic acid esale pele ka ketleleng ea pula, tobetsa ka har'a lintho tse etherified bakeng sa neutralization, phahamisa mocheso ho 75-80 ° C bakeng sa pula, mocheso o nyolohela ho 102 ° C, 'me pH. boleng ke 6 Ka hora ea 8, desolventization e phethiloe; tanka ea desolventization e tletse metsi a pompo a tšoaroang ke sesebelisoa sa reverse osmosis ho 90 ° C ho isa ho 100 ° C;

Mohato oa bohlano, ho hlatsoa centrifugal: thepa ea mohato oa bone ke centrifuged ka centrifuge screw centrifuge, 'me thepa e arohaneng e fetisetsoa tanka ea ho hlatsoa e tletseng metsi a chesang esale pele bakeng sa ho hlatsoa thepa;

Mohato oa botšelela, ho omisoa ha centrifugal: thepa e hlatsoitsoeng e fetisetsoa ka har'a se omisitsoeng ka sekontiri se otlolohileng, 'me thepa e omisitsoe ka 150-170 ° C,' me thepa e omisitsoeng e siloa ebe e kenngoa.

Ha ho bapisoa le theknoloji e teng ea tlhahiso ea cellulose ether, moqapi oa hona joale o sebelisa ethylene oxide e le etherification agent ho lokisetsa hydroxyethyl methyl cellulose, e nang le bokhoni bo botle ba ho thibela hlobo ka lebaka la ho ba le lihlopha tsa hydroxyethyl. E na le botsitso bo botle ba viscosity le ho hanyetsa hlobo nakong ea polokelo ea nako e telele. E ka sebelisoa sebakeng sa ethers tse ling tsa cellulose.