Tala'aga ma Vaaiga Aoao
O le Cellulose ether o se mea fa'aonaponei e fa'aaogaina lautele e faia mai le cellulose polymer masani e ala i togafitiga vaila'au. Ina ua maeʻa le gaosiga o le cellulose nitrate ma le cellulose acetate i le 19th seneturi, ua atiaʻe e chemists se faasologa o mea e maua mai i le cellulose o le tele o cellulose ethers, ma o loʻo maua pea avanoa fou, e aofia ai le tele o vaega o pisinisi. Cellulose ether oloa e pei ole sodiumcarboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methyl hydroxyethyl cellulose (MHEC)mamethyl hydroxypropyl cellulose (MHPC)ma isi cellulose ethers ua lauiloa o le "industrial monosodium glutamate" ma ua faʻaaogaina lautele i le suauʻu suauʻu, fausiaina, faʻaofuofu, meaʻai, vailaʻau ma vailaʻau i aso uma.
O le Hydroxyethyl methyl cellulose (MHPC) o se pa'epa'e pa'epa'e e leai se manogi, e leai se tofo, e le'o'ona e mafai ona fa'amavae i le vai malulu e fai ai se vaifofo viscous manino. O loʻo i ai uiga o le mafiafia, fusifusia, faʻasalalau, emulsifying, ata tifaga, faʻagata, adsorbing, gelling, galue i luga, tausia le susu ma le puipuia o colloid. Ona o luga o le galuega galue malosi o le vaifofo vai, e mafai ona faaaogaina e avea o se colloidal puipuiga sooupu, emulsifier ma dispersant. Hydroxyethyl methylcellulose vaifofo vai e lelei le hydrophilicity ma o se so'o lelei taofi vai. Talu ai ona o le hydroxyethyl methylcellulose o loʻo i ai vaega hydroxyethyl, e lelei lona malosi e tetee atu i le palapala, lelei le mautu o le viscosity ma le mildew i le taimi o le teuina umi.
Hydroxyethyl methylcellulose (HEMC) ua saunia e ala i le tuʻuina atu o le ethylene oxide substituents (MS 0.3 ~ 0.4) i le methylcellulose (MC), ma o lona masima e sili atu nai lo polymers e leʻi faʻaleleia. O le vevela gelation o le methylcellulose e maualuga atu foi nai lo le MC.
Fauga
Fa'aaliga
O uiga autu o le hydroxyethyl methylcellulose (HEMC) o:
1. Solubility: Solu i le vai ma nisi solvents organic. HEMC e mafai ona solo i vai malulu. O lona maualuga maualuga e na'o le fuaina o le viscosity. E eseese le solu ma le viscosity. O le maualalo o le viscosity, o le tele o le solubility.
2. Masima tetee: HEMC oloa e le-ionic cellulose ethers ma e le o polyelectrolytes, o lea e fai si mautu i vaifofo vai pe a iai masima uʻamea po electrolytes organic, ae o le faaopoopo tele o electrolytes e mafai ona mafua ai gelation ma timuga.
3. Fa'asagaga gaioioiga: Ona o le galuega galue i luga o le vaifofo vai, e mafai ona faaaogaina e avea o se colloidal puipuiga sooupu, emulsifier ma dispersant.
4. Thermal gel: Pe a vevela le vaifofo vai o oloa HEMC i se vevela faapitoa, e avea opaque, gels, ma precipitates, ae pe a faaauau pea cooled, e toe foi atu i le tulaga muamua fofo, ma le vevela lea e tupu ai lenei gel ma timuga e tele lava Faalagolago ia i latou lubricants, suspending fesoasoani, emulifiers colloids etc.
5. Metabolic inertness ma maualalo le manogi ma le manogi: HEMC e masani ona faʻaaogaina i meaʻai ma vailaʻau aua o le a le faʻafefeteina ma e maualalo le manogi ma le manogi.
6. Mildew tete'e: HEMC e fai si lelei mildew tetee ma lelei viscosity mautu i taimi umi teuina.
7. PH mautu: O le viscosity o le vaifofo vai o oloa HEMC e tau le afaina i le acid po o le alkali, ma o le tau o le pH e matua mautu i totonu ole va ole 3.0 i le 11.0.
Fa'atatauga
Hydroxyethyl methylcellulose e mafai ona faʻaaogaina e avea o se mea e puipuia ai colloidal, emulsifier ma faʻasalalau ona o lona gaioiga galue i luga o le vai. O ana fa'ata'ita'iga e fa'apea:
1. Aafiaga ole hydroxyethyl methylcellulose ile faʻatinoga ole sima. Hydroxyethyl methylcellulose ose pa'epa'e pa'epa'e e leai se manogi, e leai se tofo, e le'o'ona e mafai ona fa'amavae i le vai malulu e fai ai se vaifofo manino. O loʻo i ai uiga o le mafiafia, fusifusia, faʻasalalau, emulsifying, ata tifaga, faʻagata, adsorbing, gelling, galue i luga, tausia le susu ma le puipuia o colloid. Talu ai o le vaifofo vai o loʻo i ai se galuega galue i luga, e mafai ona faʻaaogaina e avea o se mea e puipuia ai colloidal, emulsifier ma dispersant. Hydroxyethyl methylcellulose vaifofo vai e lelei le hydrophilicity ma o se so'o lelei taofi vai.
2. Ua saunia se vali fesoasoani sili ona fetuutuunai, lea e faia i mea mataʻutia nei i vaega i le mamafa: 150-200 g o vai faʻafefe; 60-70 g o le emulsion acrylic mama; 550-650 g o le calcium mamafa; 70-90 g o le paʻu paʻu; Fofo vai o le cellulose faavae 30-40g; lignoscellulose vaifofo vai 10-20g; fesoasoani e fai ata tifaga 4-6g; antiseptic ma fungicide 1.5-2.5g; faʻasalalau 1.8-2.2g; fa'asusu susu 1.8-2.2g; 3.5-4.5g; Ethylene glycol 9-11g; O le vaifofo vai o le hydroxyethyl methylcellulose e faia e ala i le faʻamavaeina o le 2-4% hydroxyethyl methylcellulose i le vai; O le vaifofo lignoscellulose e faia i le 1-3% Lignocellulose e faia e ala i le solo i le vai.
Sauniuniga
O se metotia sauniuni o le hydroxyethyl methyl cellulose, o le auala e faʻaaogaina ai le cotton faʻamamaina e fai ma mea mata, ma o le ethylene oxide e faʻaaogaina e fai ma sui eterification e saunia ai le hydroxyethyl methyl cellulose. O vaega mamafa o meafaitino mata mo le saunia o le hydroxyethyl methylcellulose o loʻo taua i lalo: 700-800 vaega o toluene ma le isopropanol faʻafefiloi e pei o le solvent, 30-40 vaega o le vai, 70-80 vaega o le sodium hydroxide, 80-85 vaega o le cotton faʻamamaina, mama 20-28 vaega o le oxy ethane, 90-16 vaega o le oxy ethane, methyl 90, 80-90 vaega o le methyl. o le suka acetic acid; o laasaga patino o:
O le laasaga muamua, i le ulo tali, faaopoopo toluene ma isopropanol paluga, vai, ma le sodium hydroxide, vevela i le 60-80 ° C, faʻamafanafana mo le 20-40 minute;
O le laasaga lona lua, alkalization: faamalū mea i luga i le 30-50 ° C, faaopoopo cotton faamamaina, fufulu le toluene ma isopropanol paluga solvent, vacuumize i le 0.006Mpa, faatumu nitrogen mo 3 suitulaga, ma faia pe a uma le sui Alkalinization, tulaga alkalization e: o le alkalization taimi o le 2 itula, ma le alkalization 2 itula, ma le 30°C vevela;
O le laasaga lona tolu, etherification: ina ua maeʻa le alkalization, e aveese le reactor i le 0.05-0.07MPa, ma faʻaopoopo le ethylene oxide ma le methyl chloride mo le 30-50 minute; le laasaga muamua o le etherification: 40-60 ° C, 1.0-2.0 Itula, o le mamafa e pulea i le va o le 0.15 ma le 0.3Mpa; le vaega lona lua o le etherification: 60 ~ 90 ℃, 2.0 ~ 2.5 itula, o le mamafa e pulea i le va o le 0.4 ma le 0.8Mpa;
O le laasaga lona fa, neutralization: faaopoopo le fua o le suka acetic acid i luma i le ulo timuga, fetaomi atu i le etherified mea mo le neutralization, siitia le vevela i le 75-80 ° C mo timuga, o le vevela e oo atu i le 102 ° C, ma ua iloa le pH tau 6 i le 8 itula, ua maeʻa le desolventization; o le tane fa'amama e fa'atumuina i vai paipa e fa'aogaina e se masini fa'asolosolo i le 90 ° C i le 100 ° C;
O le laasaga lona lima, fufuluina centrifugal: o mea i le laasaga lona fa o loʻo faʻapipiʻiina e ala i se centrifuge faʻalava faʻalava, ma o mea tuʻueseese e faʻafeiloaʻi i se tane fufulu faʻatumu i vai vevela muamua mo le fufuluina o mea;
O le laasaga lona ono, faʻamago centrifugal: o mea fufulu e momoli atu i totonu o le mea faʻagogo e ala i se centrifuge faʻalava faʻalava, ma faʻamago mea i le 150-170 ° C, ma o mea mamago e nutimomoia ma afifi.
Pe a faatusatusa i le cellulose ether gaosiga tekinolosi, o le mea fou fou e faaaoga ethylene oxide e fai ma sui etherification e saunia ai le hydroxyethyl methyl cellulose, lea e lelei tetee mildew ona o loo i ai vaega hydroxyethyl. E lelei le viscosity mautu ma mildew tetee i taimi umi teuina. E mafai ona faʻaaogaina nai lo isi ethers cellulose.
Taimi meli: Apr-25-2024