Kedu ka esi eme cellulose ether?

Cellulose ether bụ ụdị mkpụrụ ndụ cellulose nwetara site na mgbanwe etherification nke cellulose. A na-eji ya n'ọtụtụ ebe n'ihi nkwụsi ike ya dị mma, emulsification, nkwusioru, mmepụta ihe nkiri, colloid nchebe, njigide mmiri, na ihe nrapado. Ọ na-arụ ọrụ dị mkpa na mmepe nke akụ na ụba mba na nyocha sayensị na ngalaba mmepụta ihe dị ka nri, ọgwụ, ide akwụkwọ, mkpuchi, ihe ụlọ, mgbake mmanụ, textiles na electronic components. N'akwụkwọ a, a na-enyocha ọganihu nyocha nke etherification modification nke cellulose.

Celluloseetherbụ ihe kasị ukwuu organic polymer na ọdịdị. Ọ bụ mmeghari ohuru, akwụkwọ ndụ akwụkwọ ndụ yana dakọtara. Ọ bụ ihe dị mkpa bụ isi akụrụngwa maka injinịa kemịkalụ. Dị ka ihe dị iche iche dị iche iche dị na molekul enwetara site na mmeghachi omume etherification, enwere ike kewaa ya na otu ethers na ngwakọta. cellulose ethers.Ebe a anyi na-enyocha ọganihu nyocha na njikọ nke otu ethers, gụnyere alkyl ethers, hydroxyalkyl ethers, carboxyalkyl ethers, na ngwakọta ethers.

Isi okwu: cellulose ether, etherification, otu ether, ngwakọta ether, ọganihu nyocha

1.Etherification mmeghachi omume nke cellulose

Mmeghachi omume etherification nke cellulose ether bụ ihe kacha mkpa cellulose derivatization mmeghachi omume. Etherification nke cellulose bụ usoro nke mmepụta nke mmeghachi omume nke hydroxyl otu na cellulose molekul chains na alkylating agents n'okpuru alkaline ọnọdụ. E nwere ọtụtụ ụdị cellulose ether ngwaahịa, nke nwere ike kewaa n'ime otu ethers na ngwakọta ethers dị iche iche substituents na molekul enwetara site etherification mmeghachi omume. Enwere ike kewaa otu ethers n'ime alkyl ethers, hydroxyalkyl ethers na carboxyalkyl ethers, na ethers agwakọta na-ezo aka na ethers nwere otu abụọ ma ọ bụ karịa jikọtara na nhazi ihe omimi. N'ime ngwaahịa ether cellulose, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC) na-anọchi anya, n'ime nke a na-ere ahịa ụfọdụ ngwaahịa.

2.Synthesis nke cellulose ether

2.1 Nkwekọrịta nke otu ether

Otu ethers na-agụnye alkyl ethers (dị ka ethyl cellulose, propyl cellulose, phenyl cellulose, cyanoethyl cellulose, wdg), hydroxyalkyl ethers (dị ka hydroxymethyl cellulose, hydroxyethyl cellulose, wdg), carboxyalkyl ethers (dị ka carboxymethyl cellulose, carboxymethyl cellulose, carboxymethyl cellulose). wdg).

2.1.1 Njikọ nke alkyl ethers

Berglund et al nke mbụ mesoro cellulose na ngwọta NaOH agbakwunyere na ethyl chloride, wee tinye methyl chloride na okpomọkụ nke 65.°C ruo 90°C na nrụgide nke 3bar ruo 15bar, ma meghachi omume iji mepụta methyl cellulose ether. Usoro a nwere ike ịrụ ọrụ nke ọma iji nweta ethers methyl cellulose na-agbaze mmiri na ogo dị iche iche nke nnọchi.

Ethylcellulose bụ granule ọcha ma ọ bụ ntụ ntụ. Ngwa ahịa n'ozuzu nwere 44% ~ 49% ethoxy. Soluble na ọtụtụ organic solvents, insoluble na mmiri. na pulp ma ọ bụ owu linters na 40% ~ 50% sodium hydroxide aqueous ngwọta, na alkalized cellulose e ethoxylated na ethyl chloride na-emepụta ethyl cellulose. ahazi nke ọma ethyl cellulose (EC) na ethoxy ọdịnaya nke 43.98% site a otu nzọụkwụ usoro site na-emeghachi omume cellulose na ngafe ethyl chloride na sodium hydroxide, na-eji toluene dị ka diluent. A na-eji Toluene mee ihe dị ka ihe na-edozi ahụ na nnwale ahụ. N'oge mmeghachi omume etherification, ọ bụghị naanị ịkwalite mgbasa nke ethyl chloride na cellulose alkali, kamakwa ịgbari ethyl cellulose nke ukwuu dochie anya. N'oge mmeghachi omume ahụ, akụkụ ahụ a na-emeghị eme nwere ike ikpughe na-aga n'ihu, na-eme ka onye na-ahụ maka etherification Ọ dị mfe ịwakpo, nke mere na mmeghachi omume ethylation na-agbanwe site na heterogeneous gaa n'otu n'otu, na nkesa nke ihe ndị na-anọchi anya na ngwaahịa ahụ bụ otu.

A na-eji ethyl bromide mee ihe dị ka onye na-ahụ maka etherification na tetrahydrofuran dị ka diluent iji mepụta ethyl cellulose (EC), ma kọwaa usoro ngwaahịa site na infrared spectroscopy, resonance magnetik na gel permeation chromatography. A na-agbakọ na ogo nke nnọchi nke ethyl cellulose synthesized bụ ihe dịka 2.5, nkesa nke molekụla dị warara, ọ nwekwara ezigbo solubility na ihe mgbaze organic.

cyanoethyl cellulose (CEC) site homogeneous na heterogeneous ụzọ iji cellulose na dị iche iche degrees nke polymerization dị ka akụrụngwa, na kwadebere ok CEC membrane ihe site ngwọta nkedo na-ekpo ọkụ ịpị. Ejiri teknụzụ NIPS kwadebere membranes CEC nwere oghere site na teknụzụ nkewa nke na-akpata mgbaze (NIPS), yana barium titanate/cyanoethyl cellulose (BT/CEC) nanocomposite membranes bụ teknụzụ NIPS kwadebere, ma mụọ ihe owuwu na akụrụngwa ha.

jiri onwe-mepụtara cellulose mgbaze (alkali / urea ngwọta) dị ka mmeghachi omume-ajụ ka homogeneously synthesize cyanoethyl cellulose (CEC) na acrylonitrile dị ka etherification gị n'ụlọnga, na mere nnyocha na Ọdịdị, Njirimara na ngwa nke ngwaahịa. mụọ omimi. Na site na ijikwa ọnọdụ mmeghachi omume dị iche iche, enwere ike nweta usoro CEC nwere ụkpụrụ DS sitere na 0.26 ruo 1.81.

2.1.2 Nkwekọrịta nke hydroxyalkyl ethers

Fan Junlin et al kwadebere hydroxyethyl cellulose (HEC) na 500 L reactor na-eji owu a nụchara anụcha dị ka akụrụngwa na 87.7% isopropanol-mmiri dị ka ihe mgbaze site na otu nzọụkwụ alkalization, nkwụsịtụ site na nkwụsịtụ na nzọụkwụ-site-nzọụkwụ etherification. . Nsonaazụ gosiri na hydroxyethyl cellulose a kwadebere (HEC) nwere ngbanwe molar MS nke 2.2-2.9, na-eru otu ụkpụrụ dị mma dị ka ọkwa azụmahịa Dows 250 HEC ngwaahịa nwere ngbanwe molar nke 2.2-2.4. Iji HEC na-emepụta ihe nkedo latex nwere ike imeziwanye ihe nkiri na-emepụta ihe na nhazi nke agba latex.

Liu Dan na ndị ọzọ tụlere nkwadebe nke quaternary ammonium nnu cationic hydroxyethyl cellulose site ọkara akọrọ usoro hydroxyethyl cellulose (HEC) na 2,3-epoxypropyltrimethylammonium chloride (GTA) n'okpuru edinam alkali catalysis. ọnọdụ ether. Achọpụtara mmetụta nke ịgbakwunye cationic hydroxyethyl cellulose ether na akwụkwọ. Nsonaazụ nnwale na-egosi na: na pulp hardwood na-acha ọcha, mgbe ogo ngbanwe nke cationic hydroxyethyl cellulose ether bụ 0.26, ngụkọta njigide na-abawanye site na 9%, na nzacha mmiri na-abawanye site na 14%; na pulp hardwood na-acha ọcha, mgbe ọnụọgụ nke cationic hydroxyethyl cellulose ether bụ 0.08% nke eriri pulp, ọ na-enwe mmetụta dị ike na akwụkwọ; nke ukwuu nke ngbanwe nke cellulose cationic cellulose, ka njupụta ụgwọ cationic na-abawanye, na mmetụta na-eme ka ọ dịkwuo mma.

Zhanhong na-eji usoro nhazi nke mmiri mmiri iji kwadebe hydroxyethyl cellulose nwere uru viscosity nke 5.×104mpa·s ma ọ bụ karịa na uru ntụ nke na-erughị 0.3% site na usoro nzọụkwụ abụọ nke alkalization na etherification. Eji ụzọ abụọ alkalization mee ihe. Usoro nke mbụ bụ iji acetone dị ka ihe mgbaze. Akụrụngwa cellulose na-adabere ozugbo na ụfọdụ ntinye nke ngwọta mmiri sodium hydroxide. Mgbe emechara mmeghachi omume basification, a na-agbakwunye onye na-ahụ maka etherification iji mee mmeghachi omume etherification ozugbo. Ụzọ nke abụọ bụ na cellulose raw material na-alkalized na mmiri mmiri ngwọta nke sodium hydroxide na urea, na alkali cellulose nke a kwadebere usoro a ga-squeezed iji wepụ ngafe lye tupu etherification mmeghachi omume. Nsonaazụ nnwale na-egosi na ihe ndị dị ka ọnụọgụ diluent ahọpụtara, ọnụọgụ ethylene oxide agbakwunyere, oge alkalization, okpomọkụ na oge mmeghachi omume mbụ, na okpomọkụ na oge mmeghachi omume nke abụọ niile nwere mmetụta dị ukwuu na arụmọrụ. nke ngwaahịa.

Xu Qin et al. rụrụ etherification mmeghachi omume nke alkali cellulose na propylene oxide, na synthesized hydroxypropyl cellulose (HPC) na ala nnọchi ogo site gas siri ike na-adọ usoro. A mụrụ mmetụta nke oke ntakiri nke propylene oxide, squeeze ratio na etherification okpomọkụ na ogo etherification nke HPC na iji propylene oxide dị irè. Nsonaazụ gosiri na ezigbo njikọ ọnọdụ nke HPC bụ propylene oxide mass 20% (mass ratio to cellulose), alkali cellulose extrusion ratio 3.0, na etherification okpomọkụ 60.°C. The Ọdịdị ule nke HPC site nuclear magnetik resonance na-egosi na ogo nke etherification nke HPC bụ 0.23, irè itinye n'ọrụ ọnụego nke propylene oxide bụ 41.51%, na cellulose molekul yinye na-ọma jikọọ na hydroxypropyl otu.

Kong Xingjie et al. kwadebere hydroxypropyl cellulose na ionic mmiri mmiri dị ka ihe mgbaze na-aghọta homogeneous mmeghachi omume nke cellulose ka ghọta ụkpụrụ nke mmeghachi omume usoro na ngwaahịa. N'oge nnwale ahụ, a na-eji sịntetik imidazole phosphate ionic liquid 1, 3-diethylimidazole diethyl phosphate gbazere microcrystalline cellulose, na hydroxypropyl cellulose nwetara site alkalization, etherification, acidification, na ịsa.

2.1.3 Nchịkọta nke ethers carboxyalkyl

Carboxymethyl cellulose kacha ahụkarị bụ carboxymethyl cellulose (CMC). The aqueous ngwọta nke carboxymethyl cellulose nwere ọrụ nke ndim, film akpụ, bonding, mmiri njigide, colloid nchedo, emulsification na nkwusioru, na ọtụtụ ebe na-asa. Ngwọta ọgwụ, nri, ntacha eze, textiles, ibipụta na ịcha akwa, imepụta akwụkwọ, mmanụ ala, Ngwuputa, ọgwụ, ceramik, ihe elektrọnik, rọba, agba, pesticides, ihe ịchọ mma, akpụkpọ anụ, plastik na igwu mmanụ, wdg.

Na 1918, German E. Jansen chepụtara usoro njikọ nke carboxymethyl cellulose. Na 1940, ụlọ ọrụ Kalle nke German IG Farbeninaustrie Company ghọtara mmepụta mmepụta ihe. N'afọ 1947, Wyandotle Chemical Company nke United States mepụtara usoro mmepụta ihe na-aga n'ihu nke ọma. Mba m buru ụzọ tinye n'ime mmepụta mmepụta ihe nke CMC na Shanghai Celluloid Factory na 1958. Carboxymethyl cellulose bụ cellulose ether emepụtara site na owu a nụchara anụcha n'okpuru ọrụ nke sodium hydroxide na chloroacetic acid. Enwere ike kewaa ụzọ mmepụta mmepụta ihe ya ụzọ abụọ: usoro mmiri na usoro ihe mgbaze dị ka mgbasa ozi etherification dị iche iche. Usoro eji mmiri eme ihe dị ka usoro mmeghachi omume ka a na-akpọ usoro mmiri mmiri, na usoro nwere ihe mgbaze organic na mmeghachi omume mmeghachi omume na-akpọ usoro mgbaze.

Site na omimi nke nyocha na ọganihu nke nkà na ụzụ, a na-etinye ọnọdụ mmeghachi omume ọhụrụ na njikọ nke carboxymethyl cellulose, na usoro ihe mgbaze ọhụrụ nwere mmetụta dị ukwuu na usoro mmeghachi omume ma ọ bụ àgwà ngwaahịa. Olaru et al. chọpụtara na mmeghachi omume carboxymethylation nke cellulose site na iji usoro agwakọta ethanol-acetone dị mma karịa nke ethanol ma ọ bụ acetone naanị. Nicholson et al. N'ime usoro ahụ, a kwadebere CMC nwere obere ngbanwe. Philipp et al kwadoro CMC nke ukwuu dochie ya N-methylmorpholine-N oxide na N, N dimethylacetamide/lithium chloride ihe mgbaze usoro n'otu n'otu. Cai et al. mepụtara usoro maka ịkwadebe CMC na NaOH/urea solvent system. Ramos et al. jiri sistemu mmiri mmiri DMSO/tetrabutylammonium fluoride ionic mee ihe dị ka ihe mgbaze na carboxymethylate nke cellulose akụrụngwa a nụchara anụcha site na owu na sisal, wee nweta ngwaahịa CMC nwere ogo nnọchi dị elu dị ka 2.17. Chen Jinghuan et al. A na-eji cellulose nwere nnukwu mkpokọta pulp (20%) dị ka akụrụngwa, sodium hydroxide na acrylamide dị ka mgbanwe reagents, rụrụ mmeghachi omume mgbanwe carboxyethylation n'oge oge na ọnọdụ okpomọkụ, ma mesịa nweta carboxyethyl base cellulose. Enwere ike ịhazi ọdịnaya carboxyethyl nke ngwaahịa a gbanwere site n'ịgbanwe ọnụọgụ sodium hydroxide na acrylamide.

2.2 Njikọ nke ethers agwakọta

Hydroxypropyl methyl cellulose ether bụ ụdị na-abụghị polar cellulose ether soluble na mmiri oyi enwetara site eke cellulose site alkalization na etherification mgbanwe. A na-etinye ya na ngwọta sodium hydroxide ma gbakwunye ego ole nke isopropanol na toluene mgbaze, ihe etherification na-anabata bụ methyl chloride na propylene oxide.

Dai Mingyun et al. eji hydroxyethyl cellulose (HEC) dị ka ọkpụkpụ azụ nke hydrophilic polymer, wee nyadokwa hydrophobizing agent butyl glycidyl ether (BGE) n'ime ọkpụkpụ azụ site na mmeghachi omume etherification iji dozie otu ìgwè butyl hydrophobic. Ogo nke nnọchi nke otu ahụ, ka o wee nwee uru nguzozi hydrophilic-lipophilic kwesịrị ekwesị, yana 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC) na-anabata okpomọkụ; A na-akwado ihe onwunwe na-anabata okpomọkụ Ihe na-arụ ọrụ nke cellulose na-enye ụzọ ọhụrụ maka ntinye nke ihe ndị na-arụ ọrụ n'ọhịa nke ntọhapụ ọgwụ na usoro ndu.

Chen Yangming na ndị ọzọ na-eji hydroxyethyl cellulose dị ka akụrụngwa, na na isopropanol ngwọta usoro, gbakwunyere obere ego nke Na2B4O7 na reactant maka homogeneous mmeghachi omume iji kwadebe ngwakọta ether hydroxyethyl carboxymethyl cellulose. Ngwaahịa bụ ngwa ngwa na mmiri, na viscosity kwụsiri ike.

Wang Peng na-eji eke cellulose nụchara anụcha owu dị ka isi akụrụngwa, na-eji a otu nzọụkwụ etherification usoro na-emepụta carboxymethyl hydroxypropyl cellulose na otu mmeghachi omume, elu viscosity, ezi acid iguzogide na nnu nguzogide site alkalization na etherification mmeghachi omume Compound ether. N'iji usoro etherification nke otu nzọụkwụ, carboxymethyl hydroxypropyl cellulose emepụtara nwere ezigbo nguzogide nnu, nguzogide acid na solubility. Site n'ịgbanwe nha nke propylene oxide na chloroacetic acid, enwere ike ịkwadebe ngwaahịa nwere ọdịnaya carboxymethyl na hydroxypropyl dị iche iche. Nsonaazụ ule na-egosi na carboxymethyl hydroxypropyl cellulose mepụtara site na otu nzọụkwụ nwere obere mmepụta okirikiri, obere ihe mgbaze oriri, na ngwaahịa nwere magburu onwe iguzogide monovalent na divalent salts na ezi acid iguzogide. E jiri ya tụnyere ngwaahịa ether cellulose ndị ọzọ, ọ nwere asọmpi siri ike na mpaghara nri na nchọpụta mmanụ.

Hydroxypropylmethylcellulose (HPMC) bụ ụdị dị iche iche na-arụ ọrụ nke ọma na nke kachasị mma n'etiti ụdị cellulose niile, ọ bụkwa ihe nnọchianya nke ịzụ ahịa n'etiti ethers agwakọta. Na 1927, hydroxypropylmethylcellulose (HPMC) arụpụtara nke ọma ma kewapụ ya. Na 1938, Dow Chemical Co. nke United States ghọtara mmepụta mmepụta nke methyl cellulose ma mepụta akara ụghalaahịa a ma ama "Methocel". Nnukwu mmepụta mmepụta nke hydroxypropyl methylcellulose malitere na United States na 1948. Usoro mmepụta nke HPMC nwere ike kewaa ụzọ abụọ: usoro gas na usoro mmiri mmiri. Ka ọ dị ugbu a, mba ndị mepere emepe dị ka Europe, America na Japan na-agbaso usoro nke gas, na mmepụta ụlọ nke HPMC na-adabere na usoro mmiri mmiri.

Zhang Shuangjian na ndị ọzọ nụchara anụcha ntụ ntụ dị ka akụrụngwa, alkalized ya na sodium hydroxide na mmeghachi omume mgbaze ọkara toluene na isopropanol, etherified ya na etherifying gị n'ụlọnga propylene oxide na methyl chloride, meghachi omume na kwadebere ụdị ozugbo hydroxypropyl methyl mmanya base cellulose ether.

3. Outlook

Cellulose bụ ihe dị mkpa kemịkalụ na kemịkalụ akụrụngwa nke bara ụba na akụrụngwa, akwụkwọ ndụ akwụkwọ ndụ na enyi na gburugburu ebe obibi, yana mmeghari ohuru. Ihe mmepụta nke cellulose etherification modification nwere arụmọrụ dị mma, ọtụtụ ihe eji eme ihe na mmetụta dị mma nke ọma, na-egbo mkpa nke akụ na ụba mba ruo n'ókè dị ukwuu. Na mkpa nke na-elekọta mmadụ mmepe, na-aga n'ihu na nkà na ụzụ ọganihu na mmezu nke azụmahịa na-eme n'ọdịnihu, ma ọ bụrụ na sịntetik akụrụngwa na sịntetik ụzọ nke cellulose mmepụta nwere ike ọzọ ulo oru, ha ga-n'ụzọ zuru ezu tinye n'ọrụ na-aghọta a wider nso nke ngwa. Uru.