Hydroxyethyl Methyl Cellulose

Cellulose ether bụ ihe a na-ejikarị eme ihe dị mma nke polymer sitere na cellulose polymer sitere n'okike site na ọgwụgwọ kemịkal. Mgbe emechara cellulose nitrate na cellulose acetate na narị afọ nke 19, ndị na-ahụ maka kemịkalụ ewepụtala usoro mkpụrụ ndụ cellulose nke ọtụtụ cellulose ethers, na achọpụtala mpaghara ngwa ọhụrụ na-aga n'ihu, gụnyere ọtụtụ ngalaba mmepụta ihe. Cellulose ether ngwaahịa dị ka sodium carboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methyl hydroxyethyl cellulose (MHEC) na methyl hydroxypropyl cellulose (MHPC) na ndị ọzọ cellulose ethers ka amara dị ka "Monosodium glutamate ụlọ ọrụ" na ejirila ya mee ihe n'ịgba mmanụ, ihe owuwu, ihe mkpuchi, nri, ọgwụ na kemịkalụ kwa ụbọchị.

Hydroxyethylmethylcellulose(MHEC) bụ ihe na-esi ísì ụtọ, nke na-enweghị ụtọ, ntụ ntụ na-adịghị egbu egbu nke enwere ike ịgbaze na mmiri oyi iji mepụta ngwọta viscous na-enweghị atụ. Ọ nwere àgwà nke ndim, njide, na-achụsasị, emulsifying, film-akpụ, suspending, adsorbing, gelling, elu-arụ ọrụ, ịnọgide na-enwe mmiri mmiri na-echebe colloid. N'ihi ọrụ na-arụ ọrụ elu nke ngwọta mmiri, enwere ike iji ya dị ka onye na-echebe colloidal, emulsifier na dispersant. Hydroxyethyl methylcellulose aqueous ngwọta nwere ezigbo hydrophilicity ma bụrụ onye na-ejigide mmiri nke ọma. N'ihi na hydroxyethyl methylcellulose nwere otu hydroxyethyl, ọ nwere ikike mgbochi mildew dị mma, nkwụsi ike viscosity dị mma na nguzogide mildew n'oge nchekwa ogologo oge.

A na-akwado Hydroxyethyl methylcellulose (HEMC) site na iwebata ethylene oxide substituents (MS 0.3 ~ 0.4) n'ime methylcellulose (MC), na nguzogide nnu ya dị mma karịa nke polymers na-adịghị agbanwe agbanwe. Okpomọkụ gelation nke methylcellulose dịkwa elu karịa nke MC.

Nhazi:

Njirimara:

Isi njirimara nke hydroxyethyl methylcellulose (HEMC) bụ:

1. Solubility: Solubility na mmiri na ụfọdụ ihe mgbaze organic. Enwere ike ịgbaze HEMC na mmiri oyi. A na-ekpebi itinye uche ya kachasị elu naanị site na viscosity. Solubility dị iche na viscosity. Na ala viscosity, ka ukwuu solubility.
2. Nguzogide nnu: ngwaahịa HEMC bụ ndị na-abụghị ionic cellulose ethers na ọ bụghị polyelectrolytes, n'ihi ya, ha na-adịtụ kwụsiri ike na mmiri mmiri ngwọta mgbe metal salts ma ọ bụ organic electrolytes dị, ma oké mgbakwunye nke electrolytes nwere ike ime ka gelation na mmiri ozuzo.
3. Ọrụ dị n'elu: N'ihi ọrụ na-arụ ọrụ elu nke ngwọta mmiri, enwere ike iji ya dị ka onye na-ahụ maka nchebe colloidal, emulsifier na dispersant.
4. Gel thermal: Mgbe ngwọta mmiri nke ngwaahịa HEMC na-ekpo ọkụ na okpomọkụ, ọ na-aghọ opaque, gels, na precipitates, ma mgbe ọ na-anọgide na-ajụ oyi, ọ na-alaghachi na ọnọdụ ngwọta mbụ, na okpomọkụ nke gel na mmiri ozuzo. emee bụ tumadi Dabere na ha mmanu mmanu, suspending aids, echebe colloid, emulsifiers wdg.
5. Metabolism inert na obere isi na isi ísì: A na-eji HEMC eme ihe n'ọtụtụ nri na ọgwụ n'ihi na ọ gaghị eme ka ọ bụrụ metabolized ma nwee obere isi na isi ísì.
6. Nguzogide mildew: HEMC nwere nguzogide mildew dị mma yana nkwụsi ike viscosity dị mma n'oge nchekwa ogologo oge.
7. Nkwụsi ike PH: Acid ma ọ bụ alkali adịghị emetụta viscosity nke ngwọta mmiri mmiri nke ngwaahịa HEMC, yana uru pH kwụsiri ike n'etiti 3.0 ruo 11.0.

Ngwa:

Enwere ike iji Hydroxyethyl methylcellulose mee ihe dị ka onye na-ahụ maka nchebe colloidal, emulsifier na dispersant n'ihi ọrụ elu ya na-arụ ọrụ na ngwọta mmiri. Ọmụmaatụ ngwa ya bụ ndị a:

1. Mmetụta nke hydroxyethyl methylcellulose na arụ ọrụ ciment. Hydroxyethyl methylcellulose bụ ihe na-esighi ísì, enweghị ụtọ, ntụ ntụ ọcha na-adịghị egbu egbu nke enwere ike igbari na mmiri oyi iji mepụta ngwọta viscous na-apụta ìhè. Ọ nwere àgwà nke ndim, njide, na-achụsasị, emulsifying, film-akpụ, suspending, adsorbing, gelling, elu-arụ ọrụ, ịnọgide na-enwe mmiri mmiri na-echebe colloid. Ebe ọ bụ na ngwọta mmiri nwere elu na-arụsi ọrụ ike, enwere ike iji ya dị ka onye na-echebe colloidal, emulsifier na dispersant. Hydroxyethyl methylcellulose aqueous ngwọta nwere ezigbo hydrophilicity ma bụrụ onye na-ejigide mmiri nke ọma.
2. A na-edozi agba enyemaka nke nwere mgbanwe dị elu, nke a na-eji ihe ndị na-esonụ na-eme ka ọ bụrụ ihe dị arọ: 150-200 g nke mmiri deionized; 60-70 g nke acrylic emulsion dị ọcha; 550-650 g nke calcium dị arọ; 70-90 g nke ntụ ntụ ntụ ntụ; 30-40g isi cellulose mmiri ngwọta; 10-20 g lignocellulose ngwọta mmiri; 4-6g ihe eji eme ihe nkiri; 1.5-2.5 g nke antiseptik na bactericides; 1.8-2.2g nkesa; 3.5-4.5g; Ethylene glycol 9-11 g; A na-eme ngwọta mmiri hydroxyethyl methylcellulose site na igbari 2-4% hydroxyethyl methylcellulose na mmiri; A na-eme ngwọta mmiri lignocellulose nke 1-3% Lignocellulose site na igbari na mmiri.

Nkwadebe:

Usoro nkwadebe nke hydroxyethyl methylcellulose, usoro a bụ iji owu a nụchara anụcha dị ka ihe eji eme ihe na ethylene oxide dị ka ihe etherification iji kwadebe hydroxyethyl methylcellulose. Akụkụ dị arọ nke akụrụngwa maka ịkwadebe hydroxyethyl methyl cellulose bụ ndị a: akụkụ 700-800 nke toluene na ngwakọta isopropanol dị ka ihe mgbaze, akụkụ 30-40 mmiri, akụkụ 70-80 nke sodium hydroxide, akụkụ 80-85 nke owu a nụchara anụcha, mgbanaka 20-28 akụkụ nke oxyethane, 80-90 akụkụ nke methyl chloride, 16-19 akụkụ nke glacial acetic acid; usoro ndị a kapịrị ọnụ bụ:

Nzọụkwụ mbụ, na kettle mmeghachi omume, tinye toluene na ngwakọta isopropanol, mmiri, na sodium hydroxide, na-ekpo ọkụ ruo 60-80 Celsius C, na-ekpo ọkụ maka nkeji 20-40;

Nzọụkwụ nke abụọ, alkalization: mee ka ihe ndị dị n'elu dị jụụ ruo 30-50 ° C, gbakwunye owu a nụchara anụcha, fesa toluene na isopropanol ngwakọta ihe mgbaze, gbanye ya na 0.006Mpa, jupụta nitrogen maka 3 ndochi, ma mee mgbe dochie Alkalinization, na Ọnọdụ alkalization bụ: oge ​​alkalization bụ awa 2, na alkalisation okpomọkụ bụ 30 ° C ruo 50 ° C;

Nzọụkwụ nke atọ, etherification: mgbe emechara alkalization, a na-ewepụ onye na-emepụta ihe na 0.05-0.07MPa, na ethylene oxide na methyl chloride na-agbakwunye maka nkeji 30-50; ọkwa mbụ nke etherification: 40-60 ° C, 1.0-2.0 Awa, a na-achịkwa nrụgide n'etiti 0.15 na 0.3Mpa; nke abụọ ogbo nke etherification: 60 ~ 90 ℃, 2.0 ~ 2.5 awa, a na-achịkwa nrụgide n'etiti 0.4 na 0.8Mpa;

Nzọụkwụ nke anọ, neutralization: Tinye ntụ ntụ glacial acetic acid tupu oge eruo na kettle mmiri ozuzo, pịa n'ime ihe etherified maka neutralization, bulie okpomọkụ ruo 75-80 ° C maka mmiri ozuzo, okpomọkụ na-ebili na 102 ° C, na pH. uru bụ 6 N'elekere asatọ nke ụtụtụ, a na-emecha desolventization; A na-ejupụta tankị na-emebi emebi na mmiri mgbata nke ngwaọrụ reverse osmosis na-edozi na 90 Celsius C ruo 100 Celsius;

Nzọụkwụ nke ise, ịsacha centrifugal: ihe dị na nzọụkwụ nke anọ bụ ihe na-eme ka ọ bụrụ ihe na-eme ka ọ bụrụ ihe na-eme ka ọ dị elu site na nkwụsị nke centrifuge, na ihe ndị ahụ kewara ekewa na-ebufe na tankị ịsacha nke jupụtara na mmiri ọkụ tupu oge eruo maka ịsacha ihe;

Nzọụkwụ nke isii, ihicha centrifugal: a na-ebufe ihe ndị a na-asacha n'ime igwe na-ekpo ọkụ site na centrifuge screw centrifuge, na ihe a na-akpọnwụ na 150-170 ° C, na-egweri ihe a mịrị amị na ngwugwu.

Tụnyere teknụzụ mmepụta cellulose ether dị ugbu a, ihe a na-emepụta ugbu a na-eji ethylene oxide dị ka onye na-ahụ maka etherification iji kwadebe hydroxyethyl methyl cellulose, nke nwere ikike mgbochi ebu n'ihi na ọ nwere otu hydroxyethyl. Ọ nwere ezigbo nkwụsi ike viscosity na iguzogide mildew n'oge nchekwa ogologo oge. Enwere ike iji ya kama ethers cellulose ndị ọzọ.