Hydroxypropyl Methyl Cellulose Ether Technology

Hydroxypropyl methyl cellulose ether bụ ụdị nonpolar cellulose ether soluble na mmiri oyi enwetara site eke cellulose site alkalization na etherification mgbanwe.

Okwu:hydroxypropyl methylcellulose ether; mmeghachi omume alkalization; mmeghachi omume etherification

1. Teknụzụ

Natural cellulose bụ insoluble na mmiri na organic solvents, ike ka ìhè, okpomọkụ, acid, nnu na ndị ọzọ chemical media, na ike moistened na itughari alkali ngwọta ịgbanwe elu nke cellulose.

Hydroxypropyl methyl cellulose ether bụ ụdị na-abụghị polar, oyi mmiri-soluble cellulose ether enwetara site eke cellulose site alkalization na etherification mgbanwe.

2. Isi usoro mmeghachi omume chemical

2.1 mmeghachi omume Alkalization

Enwere ohere abụọ maka mmeghachi omume nke cellulose na sodium hydroxide, ya bụ, dị ka ọnọdụ dị iche iche si emepụta ogige molecular, R - OH - NaOH; ma ọ bụ imepụta ogige mmanya na-egbu igwe, R - ONa.

Ọtụtụ ndị ọkà mmụta kwenyere na cellulose na-emeghachi omume na alkali gbanyere mkpọrọgwụ iji mepụta ihe edozi, ma na-eche na otu glucose ma ọ bụ abụọ jikọtara ya na otu molecule NaOH (otu glucose na-ejikọta ya na mkpụrụ ndụ NaOH atọ mgbe mmeghachi omume zuru ezu).

C6H10O5 + NaOH→C6H10O5 NaOH ma ọ bụ C6H10O5 + NaOH→C6H10O4 ONa + H2O

C6H10O5 + NaOH→(C6H10O5 ) 2 NaOH ma ọ bụ C6H10O5 + NaOH→C6H10O5 C6H10O4 ONa + H2O

N'oge na-adịbeghị anya, ụfọdụ ndị ọkà mmụta kwenyere na mmekọrịta dị n'etiti cellulose na alkali na-etinye uche ga-enwe mmetụta abụọ n'otu oge.

N'agbanyeghị usoro ahụ, ọrụ kemịkalụ nke cellulose nwere ike gbanwee mgbe ọrụ cellulose na alkali gasịrị, ọ pụkwara imeghachi omume na usoro mgbasa ozi dị iche iche iji nweta ụdị bara uru.

2.2 mmeghachi omume etherification

Mgbe alkalization gasịrị, alkali cellulose na-arụ ọrụ na-emeghachi omume na onye na-ahụ maka etherification iji mepụta cellulose ether. Ihe ndị na-eme ka etherifying na-eji bụ methyl chloride na propylene oxide.

Sodium hydroxide na-arụ ọrụ dị ka ihe na-akpali akpali.

n na m na-anọchi anya ogo ngbanwe nke hydroxypropyl na methyl na akụkụ cellulose, n'otu n'otu. Nchikota kacha nke m + n bụ 3.

Na mgbakwunye na mmeghachi omume bụ isi a kpọtụrụ aha n'elu, enwerekwa mmeghachi omume akụkụ:

CH2CH2OCH3 + H2O→HOCH2CH2OHCH3

CH3Cl + NaOH→CH3OH + NaCl

3. Usoro nkọwa nke hydroxypropyl methylcellulose ether

Usoro nke hydroxypropyl methyl cellulose ether ("cellulose ether" maka nkenke) bụ ihe mejupụtara nke usoro 6, ya bụ: ihe ọkụkụ na-egwepịa ihe, (alkalinization) etherification, mwepụ ihe mgbaze, filtration na ihicha, nchicha na ịgwakọta, na nkwakọ ngwaahịa emecha.

3.1 Nkwadebe akụrụngwa

A na-egwepịa cellulose dị mkpụmkpụ-lint eke eke zụtara n'ahịa ka ọ bụrụ ntụ ntụ site na pulverizer iji kwado nhazi na-esote; A na-agbaze alkali siri ike (ma ọ bụ alkali mmiri mmiri) ma kwadebe ya, wee kpoo ọkụ ruo ihe dịka 90°C ime ka 50% caustic soda ngwọta maka ojiji. Kwadebe mmeghachi omume methyl chloride, propylene oxide etherification agent, isopropanol na toluene ihe mgbaze n'otu oge.

Tụkwasị na nke ahụ, usoro mmeghachi omume chọrọ ihe enyemaka dị ka mmiri ọkụ na mmiri dị ọcha; uzuoku, mmiri jụrụ oyi dị ala, na mmiri jụrụ oyi na-ekesa ka achọrọ iji nyere ike aka.

Mpempe akwụkwọ dị mkpirikpi, methyl chloride, na propylene oxide etherification agents bụ ihe ndị bụ isi maka imepụta cellulose etherified, na obere linters na-eji nnukwu ego. Methyl chloride na propylene oxide na-ekere òkè na mmeghachi omume dị ka ndị na-eme ka etherification gbanwee cellulose eke, ọnụ ọgụgụ nke ojiji adịghị nnukwu.

Ihe mgbaze (ma ọ bụ ihe ndị na-edozi ahụ) na-agụnyekarị toluene na isopropanol, bụ ndị a na-adịghị ericha ya, ma n'ihi mfu ndị na-emepụta ihe na ndị na-agbanwe agbanwe, a na-enwe ntakịrị mfu na mmepụta, na ego ejiri ya dị ntakịrị.

Usoro nkwadebe akụrụngwa nwere mpaghara tankị akụrụngwa yana ụlọ nkwakọba ihe ejikọtara. A na-echekwa ihe ndị na-emepụta ihe na ihe mgbaze, dị ka toluene, isopropanol, na acetic acid (nke a na-eji dozie uru pH nke ndị na-eme ihe), na-echekwa na mpaghara tankị akụrụngwa. Ọbịbịa nke obere lint zuru oke, ahịa nwere ike ịnye ya n'oge ọ bụla.

A na-eziga lint dị mkpụmkpụ a gbajiri agbaji na ogbako ahụ yana ụgbọ ala maka ojiji.

3.2 (Alkalinization) etherification

(Alkaline) etherification bụ usoro dị mkpa na usoro etherification nke cellulose. Na usoro mmepụta mbụ, a na-eme mmeghachi omume abụọ ahụ iche iche. Ugbu a, a na-eme ka usoro ahụ dịkwuo mma, a na-ejikọta mmeghachi omume abụọ ahụ n'otu ọkwa ma mee n'otu oge.

Nke mbụ, kpochapu tankị etherification iji wepụ ikuku, wee dochie ya na nitrogen iji mee ka tank ahụ ghara inwe ikuku. Gbakwunye ihe ngwọta sodium hydroxide a kwadebere, gbakwunye ụfọdụ isopropanol na toluene solvent, malite ịkpali, wee tinye obere owu owu, gbanye mmiri na-ekesa ka ọ dị jụụ, ma mgbe okpomọkụ dara na ọkwa ụfọdụ, gbanye obere ala- mmiri okpomọkụ iji wedata okpomọkụ ihe sistemu ahụ Wedata ihe dịka 20℃, ma nọgide na-emeghachi omume maka oge ụfọdụ iji mezue alkalization.

Mgbe alkalization gasịrị, gbakwunye onye na-ahụ maka etherifying methyl chloride na propylene oxide tụrụ site na tank nke dị elu, nọgide na-amalite ịkpali, jiri uzuoku mee ka usoro okpomọkụ dị ihe fọrọ nke nta ka ọ bụrụ 70.℃~ 80℃, wee jiri mmiri ọkụ na-aga n'ihu na-ekpo ọkụ na ịnọgide na-enwe okpomọkụ mmeghachi omume na-achịkwa, mgbe ahụ, a na-achịkwa okpomọkụ mmeghachi omume na oge mmeghachi omume, na ọrụ ahụ nwere ike mechaa site n'ịkpali na ịgwakọta ruo oge ụfọdụ.

A na-eme mmeghachi omume ahụ n'ihe dịka 90°C na 0.3 MPa.

3.3 Ntọgbọrọ n'efu

A na-ezigara ihe ndị a na-emeghachi omume n'elu na desolventizer, a na-ewepụkwa ihe ndị ahụ ma kpoo ọkụ na uzuoku, na toluene na isopropanol solvents na-ekpochapụ ma nwetaghachi maka imegharị ya.

A na-ebu ụzọ mee ka ihe mgbaze na-ekpo ọkụ na-eme ka ọ dị jụụ ma na-ekpuchi ya na mmiri na-ekesa, wee kpoo ya na mmiri dị ala, na ngwakọta condensate na-abanye n'ime mmiri mmiri na ihe nkesa iji kewaa mmiri na ihe mgbaze. A na-edozi ihe mgbaze agwakọta nke toluene na isopropanol dị n'elu oyi akwa n'ụzọ kwesịrị ekwesị. Jiri ya ozugbo, ma weghachite mmiri na ngwọta isopropanol na oyi akwa dị ala na desolventizer maka ojiji.

Tinye acetic acid na reactant mgbe ọ tọgbọrọ n'efu iji wepụ oke sodium hydroxide, wee jiri mmiri ọkụ na-asa ihe ahụ, jiri njirimara coagulation nke cellulose ether mee ihe n'ụzọ zuru ezu na mmiri ọkụ iji sachaa cellulose ether, ma nụchaa ihe na-emeghachi omume. A na-ezigara ihe ndị a nụchara anụcha na usoro ọzọ maka nkewa na ihicha.

3.4 Nzacha na nkụ

The nụchara anụcha ihe na-eziga na kehoraizin ịghasa separator site elu-nrụgide ịghasa mgbapụta ikewapụ free mmiri, na ndị fọdụrụ siri ike ihe na-abanye ikuku draya site na ịghasa feeder, na akpọnwụwo na kọntaktị na-ekpo ọkụ ikuku, na mgbe ahụ gafere site cyclone. nkewa na ikuku nkewa, ihe siri ike na-abanye n'ọkpụkpụ na-esote.

Mmiri nke kewapụrụ site na onye na-ahụ maka gburugburu ebe obibi na-abanye n'ime mmiri na-edozi mmiri mgbe ọ na-agbaze n'ime mmiri na-ekpo ọkụ iji kewapụ cellulose a na-agbanye.

3.5 Na-etipịa na ịgwakọta

Mgbe ihicha, na etherified cellulose ga-enweghi uru urughuru size, nke kwesịrị ka-echi ọnụ n'ala na agwakọta nke mere na urughuru size nkesa na n'ozuzu ọdịdị nke ihe izute ngwaahịa ọkọlọtọ chọrọ.

3. 6 Nkwakọ ngwaahịa emechara

Ihe a na-enweta mgbe a na-egwepịa ya na ịgwakọta ọrụ bụ cellulose etherified emechara, nke nwere ike ịkwado ma tinye ya na nchekwa.

4. Nchịkọta

Mmiri mkpofu ahụ kewapụrụ nwere ntakịrị nnu, ọkachasị sodium chloride. A na-ekpochapụ mmiri mkpofu iji kewaa nnu, na uzuoku nke abụọ ekpochapụ nwere ike ịgbanye ka ọ nwetaghachi mmiri a gbakọrọ agbakọ, ma ọ bụ wepụ ya ozugbo. Akụkụ bụ isi nke nnu kewapụrụ iche bụ sodium chloride, nke nwekwara ụfọdụ sodium acetate n'ihi nkwụsịtụ na acetic acid. Nnu a nwere uru eji arụ ọrụ ụlọ ọrụ naanị mgbe recrystallization, nkewa na sachaa.