Focus on Cellulose ethers

E faʻapefea ona faia le Cellulose ether?

E faʻapefea ona faia le Cellulose ether?

Cellulose ether o se ituaiga cellulose derivative maua mai etherification suiga o cellulose.E faʻaaogaina lautele ona o lona mafiafia sili ona lelei, emulsification, faʻamalolo, faʻatulagaina ata, colloid puipuia, faʻamauina o le susu, ma mea faʻapipiʻi.E iai sona sao taua i le atinaʻeina o le tamaoaiga o le atunuʻu i suʻesuʻega faʻasaienisi ma vaega faʻapisinisi e pei o meaʻai, vailaʻau, fai pepa, faʻapipiʻi, mea faufale, toe faʻaleleia o suauʻu, ie ma mea faʻaeletoroni.I totonu o lenei pepa, o loʻo iloiloina le alualu i luma o suʻesuʻega o suiga ole etherification ole cellulose.

Selulosaeteruo le polymer organic sili ona tele i le natura.E fa'afouina, lanu meamata ma biocompatible.Ose mea fa'avae taua mo le inisinia kemisi.E tusa ai ma suiga eseese i luga o le mole maua mai le etherification tali, e mafai ona vaevaeina i ethers tasi ma fefiloi. selulosa eteru.O i matou nei toe iloilo le alualu i luma o suʻesuʻega i le tuʻufaʻatasia o ethers e tasi, e aofia ai alkyl ethers, hydroxyalkyl ethers, carboxyalkyl ethers, ma ethers fefiloi.

upu autu: selulosa eteru, etherification, eter e tasi, eter fefiloi, alualu i luma suʻesuʻega

 

1. Etherification tali ole cellulose

 

O le fa'afefeteina o le cellulose eteru o le sili ona taua cellulose derivatization reaction.Etherification o cellulose o se faasologa o derivatives gaosia e le tali o vaega hydroxyl i luga o filifili mole mole cellulose ma sui alkylating i lalo o tulaga alkaline.E tele ituaiga o cellulose ether oloa, lea e mafai ona vaevaeina i ethers e tasi ma ethers fefiloi e tusa ai ma suitulaga eseese i luga o molelaʻau maua mai le tali etherification.E mafai ona vaevaeina ethers nofofua i alkyl ethers, hydroxyalkyl ethers ma carboxyalkyl ethers, ma ethers fefiloi e faasino i ethers e lua pe sili atu vaega e fesoʻotaʻi i le fausaga mole.I totonu o oloa cellulose ether, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), hydroxypropyl methyl cellulose (HPMC) o loʻo faʻatusalia, faatasi ai ma nisi o oloa ua faʻatau pisinisi.

 

2.Synthesis o le cellulose ether

 

2.1 Fa'asologa o se eter e tasi

O ethers nofofua e aofia ai alkyl ethers (e pei o le ethyl cellulose, propyl cellulose, phenyl cellulose, cyanoethyl cellulose, ma isi), hydroxyalkyl ethers (e pei o le hydroxymethyl cellulose, hydroxyethyl cellulose, ma isi), carboxyalkyl ethers (e pei o le carboxylosemethyl cellulose, cellulose carboxymethylyethyl. ma isi).

2.1.1 Fa'asologa o alkyl ethers

Na muamua togafitia e Berglund ma le cellulose i le NaOH solution faaopoopo i le ethyl chloride, ona faaopoopo lea o le methyl chloride i le vevela o le 65.°C i le 90°C ma le mamafa o le 3bar i le 15bar, ma tali atu e maua ai le methyl cellulose ether.O lenei metotia e mafai ona sili ona lelei Ina ia maua le vai-soluble methyl cellulose ethers ma tikeri eseese o suiga.

Ethylcellulose o se paʻepaʻe paʻepaʻe paʻu poʻo se paʻu.O oloa lautele e aofia ai le 44% ~ 49% ethoxy.Solu i le tele o solu fa'aletino, e le mafai ona solu i le vai.le pulupulu po o le cotton linters ma 40% ~ 50% sodium hydroxide vaifofo vai, ma le cellulose alkalized sa ethoxylated ma ethyl chloride e maua ai le ethyl cellulose.fa'alelei fa'atasi le ethyl cellulose (EC) fa'atasi ai ma le ethoxy anotusi o le 43.98% i se auala e tasi-laasaga e ala i le taliina o le cellulose ma le sili atu o le ethyl chloride ma le sodium hydroxide, e fa'aaoga ai le toluene e fai ma fa'afefiloi.O le Toluene na fa'aaogaina e fai ma vaisu i le su'ega.I le taimi o le etherification tali, e le gata e mafai ona faʻalauteleina le faʻasalalauina o le ethyl chloride i le alkali cellulose, ae faʻamavae foi le ethyl cellulose sili ona sui.I le taimi o le tali, e mafai ona faʻaauau pea ona faʻaalia le vaega e leʻi faʻaalia, faia le etherification agent E faigofie ona osofaʻia, ina ia suia le tali o le ethylation mai le heterogeneous i le homogeneous, ma o le tufatufaina atu o sui i totonu o le oloa e sili atu le tutusa.

fa'aaogaina le ethyl bromide e fai ma sui etherification ma le tetrahydrofuran e fa'afefiloi e fa'apipi'i ai le ethyl cellulose (EC), ma fa'aalia le fausaga o oloa e ala ile infrared spectroscopy, nuclear magnetic resonance ma gel permeation chromatography.Ua fuafuaina o le tikeri o le suitulaga o le synthesized ethyl cellulose e tusa ma le 2.5, o le tufatufaina atu o mole mole e vaapiapi, ma e lelei le solubility i solvents organic.

cyanoethyl cellulose (CEC) e ala i metotia tutusa ma heterogeneous e faʻaaoga ai le cellulose ma tikeri eseese o le polymerization e pei o mea mata, ma saunia mea faʻapipiʻi CEC e ala i le fofo o le fofo ma le vevela vevela.Porous CEC membranes na saunia e solvent-induced phase separation (NIPS) technology, ma le barium titanate / cyanoethyl cellulose (BT / CEC) nanocomposite membrane material na saunia e tekinolosi NIPS, ma o latou fausaga ma meatotino sa suʻesuʻeina.

faʻaaogaina le solvent cellulose na faʻavaeina e le tagata lava ia (alkali / urea solution) e pei o le tali atu i le homogeneously synthesize cyanoethyl cellulose (CEC) ma le acrylonitrile e avea ma sui etherification, ma faia suʻesuʻega i luga o le fausaga, meatotino ma le faʻaogaina o le oloa.suesue loloto.Ma e ala i le faʻatonutonuina o tulaga faʻaalia eseese, e mafai ona maua se faasologa o CEC faʻatasi ai ma tau DS mai le 0.26 i le 1.81.

2.1.2 Fa'atupuina ole hydroxyalkyl ethers

Fan Junlin et al saunia hydroxyethyl cellulose (HEC) i le 500 L reactor faʻaaogaina le cotton faʻamamaina e pei o mea mata ma le 87.7% isopropanol-vai e pei o le solvent e ala i le tasi-step alkalization, laʻasaga-i-step neutralization ma laʻasaga-laasaga etherification..O faʻaiʻuga na faʻaalia ai o le hydroxyethyl cellulose (HEC) ua saunia sa i ai se MS molar sui o le 2.2-2.9, e oʻo atu i le tulaga tutusa lelei e pei o le oloa faʻatau oloa Dows 250 HEC faʻatasi ai ma se sui molar o le 2.2-2.4.O le fa'aogaina o le HEC i le gaosiga o le latex vali e mafai ona fa'aleleia atili ai le fa'aogaina o ata ma le fa'avasegaina o mea o le vali latex.

Na talanoaina e Liu Dan ma isi le sauniuniga o le quaternary ammonium salt cationic hydroxyethyl cellulose e ala i le semi-dry method of hydroxyethyl cellulose (HEC) ma le 2,3-epoxypropyltrimethylammonium chloride (GTA) i lalo o le gaioiga o le alkali catalysis.tulaga eter.O le a'afiaga o le fa'aopoopoina o le cationic hydroxyethyl cellulose ether i luga o pepa sa su'esu'eina.O faʻataʻitaʻiga faʻataʻitaʻiga o loʻo faʻaalia ai: i totonu o le pulupulu laupapa faʻamaʻi, pe a oʻo i le tikeri sui o le cationic hydroxyethyl cellulose ether o le 0.26, o le aofaʻi o le faʻatumauina o le faʻatuputeleina e 9%, ma le faʻaleleia o le vai e 14%;i le pulupulu laupapa malo bleached, pe a A o le aofaiga o le cationic hydroxyethyl cellulose eter e 0.08% o le alava pulupulu, e i ai se aafiaga malosi faamalosia i luga o pepa;o le maualuga o le tikeri o le suia o le cationic cellulose ether, o le sili atu lea o le mamafa o le cationic charge, ma sili atu le faʻamalosia.

E fa'aogaina e Zhanhong le fa'aogaina o le vai-vaega auala e saunia ai le hydroxyethyl cellulose fa'atasi ai ma le tau viscosity o le 5.×104mPa·s pe sili atu ma se tau lefulefu e itiiti ifo i le 0.3% e ala i le laasaga e lua o le alkalization ma etherification.E lua auala e fa'aaogaina ai le alkali.O le auala muamua o le faʻaaogaina o le acetone e fai ma faʻafefe.Ole mea mata ole cellulose o lo'o fa'avae sa'o i se fa'atonuga o le vaifofo vai o le sodium hydroxide.A maeʻa ona faʻataunuʻuina le tali faʻavae, e faʻaopoopoina se sui etherification e faʻataunuʻu saʻo ai le tali etherification.O le auala lona lua e faapea o le cellulose mea mata ua alkalized i se vaifofo vai o le sodium hydroxide ma urea, ma le cellulose alkali saunia e lenei metotia e tatau ona oomi e aveese le sili atu lye i luma o le etherification tali.O faʻataʻitaʻiga faʻataʻitaʻiga o loʻo faʻaalia ai o mea taua e pei o le aofaʻi filifilia, le aofaʻi o le ethylene oxide ua faʻaopoopoina, le taimi o le alkalization, le vevela ma le taimi o le tali muamua, ma le vevela ma le taimi o le tali lona lua o loʻo i ai uma se aafiaga tele i le faatinoga. o le oloa.

Xu Qin et al.faia tali etherification o alkali cellulose ma propylene oxide, ma synthesized hydroxypropyl cellulose (HPC) ma le maualalo tikeri suitulaga e ala kasa-malosi auala vaega.O aʻafiaga o le vaega tele o le propylene oxide, o le faʻaogaina o le fua ma le vevela o le etherification i luga o le tikeri o le etherification o le HPC ma le faʻaogaina lelei o le propylene oxide na suʻesuʻeina.O faʻaiʻuga na faʻaalia ai o tulaga sili ona lelei o le faʻapipiʻiina o le HPC o le propylene oxide vaega o le tele o le 20% (faʻasologa o le mamafa i le cellulose), fua faatatau o le faʻaogaina o le cellulose alkali 3.0, ma le vevela o le etherification 60°C. O le suʻega o le fausaga o le HPC e ala i le faʻamaneta faaniukilia e faʻaalia ai o le tikeri o le etherification o le HPC o le 0.23, o le faʻaogaina lelei o le propylene oxide o le 41.51%, ma o le filifili mole mole cellulose e fesoʻotaʻi lelei ma vaega hydroxypropyl.

Kong Xingjie et al.saunia hydroxypropyl cellulose ma vai ionic e pei o se solvent e iloa ai le tali tutusa o cellulose ina ia iloa ai le tulafono faatonutonu o le faagasologa tali ma oloa.I le taimi o le faʻataʻitaʻiga, o le synthetic imidazole phosphate ionic liquid 1, 3-diethylimidazole diethyl phosphate na faʻaaogaina e faʻaumatia ai le microcrystalline cellulose, ma le hydroxypropyl cellulose na maua e ala i le alkalization, etherification, acidification, ma le fufuluina.

2.1.3 Fa'asologa o carboxyalkyl ethers

Ole carboxymethyl cellulose sili ona masani ole carboxymethyl cellulose (CMC).O le vaifofo vai o le carboxymethyl cellulose o loʻo i ai galuega o le mafiafia, faʻapipiʻiina o ata, faʻapipiʻi, taofi vai, puipuiga colloid, emulsification ma faʻamalolo, ma e faʻaaogaina lautele i le fufuluina.Pharmaceuticals, food, toothpaste, textiles, lomitusi ma vali, faipepa, petroleum, mining, vailaau, ceramics, mea faaeletonika, paʻu, vali, vailaau faʻamaʻi, mea teuteu, paʻu, palasitika ma suauʻu vili, ma isi.

I le 1918, na faia ai e Siamani E. Jansen le auala faʻapipiʻi o le carboxymethyl cellulose.I le 1940, o le fale gaosi Kalle o le Siamani IG Farbeninaustrie Kamupani na iloa ai le gaosiga o pisinisi.I le 1947, o le Wyandotle Chemical Company a le Iunaite Setete na faʻataunuʻuina ma le manuia se faʻagasologa o gaosiga faifaipea.o loʻu atunuu na muamua tuʻuina i totonu o le CMC gaosiga faʻapisinisi i Shanghai Celluloid Factory i le 1958. Carboxymethyl cellulose o se cellulose ether na gaosia mai le cotton faʻamamaina i lalo o le gaioiga o le sodium hydroxide ma le chloroacetic acid.E mafai ona vaevaeina lona gaosiga o alamanuia auala i ni vaega se lua: vai-faavae auala ma solvent-faavae auala e tusa ai ma ala o faasalalauga etherification eseese.O le fa'agasologa o le fa'aogaina o le vai e pei o le ala fa'afoliga e ta'ua o le auala vai, ma o le fa'agasologa o lo'o i ai se solvent organic i totonu o le tali fa'afefe e ta'ua o le solvent method.

Faatasi ai ma le faʻalolotoina o suʻesuʻega ma le alualu i luma o tekinolosi, ua faʻaaogaina tulaga fou o tali i le tuʻufaʻatasia o le carboxymethyl cellulose, ma o le faiga fou o le solvent ei ai sona aafiaga taua i le gaioiga o le tali poʻo le lelei o oloa.Olaru et al.na maua ai e sili atu le tali atu o le carboxymethylation o le cellulose e faʻaaogaina ai le ethanol-acetone nai lo le ethanol poʻo le acetone naʻo ia.Nicholson et al.I totonu o le faiga, na saunia le CMC ma le maualalo o le suiga.Philipp et al saunia sili ona suitulaga CMC ma N-methylmorpholine-N oxide ma le N, N dimethylacetamide/lithium chloride solvent systems i le faasologa.Cai et al.fausia se auala mo le saunia CMC i le NaOH/urea solvent system.Ramos et al.faʻaaogaina le DMSO / tetrabutylammonium fluoride ionic liquid system e avea o se solvent e carboxymethylate le cellulose raw material faʻamamaina mai le cotton ma le sisal, ma maua ai se oloa CMC ma se tikeri suitulaga maualuga e pei o le 2.17.Chen Jinghuan et al.fa'aogaina le cellulose ma le maualuga o le pulupulu (20%) e pei o mea mata, sodium hydroxide ma acrylamide e fai ma sui suiga, fa'ataunu'u le suiga o le carboxyethylation i le taimi ma le vevela, ma mulimuli ane maua ai le cellulose faavae carboxyethyl.Ole mea ole carboxyethyl ole oloa faʻaleleia e mafai ona faʻatonutonuina e ala ile suia ole aofaʻi ole sodium hydroxide ma acrylamide.

2.2 Fa'asologa o ethers fefiloi

Hydroxypropyl methyl cellulose ether o se ituaiga e le polar cellulose ether soluble i vai malulu maua mai cellulose natura e ala i alkalization ma etherification suiga.E alkalized i le vaifofo sodium hydroxide ma faaopoopo se aofaiga o le aofaiga o le isopropanol ma toluene solvent, o le etherification sui e faaaogaina o le methyl chloride ma propylene oxide.

Dai Mingyun et al.fa'aaoga le hydroxyethyl cellulose (HEC) e fai ma ivi tua o le polymer hydrophilic, ma fa'apipi'i le hydrophobizing agent butyl glycidyl eter (BGE) i luga o le ivi tua e ala i le etherification tali e fetuunai ai le vaega hydrophobic butyl vaega.Le tikeri o le suitulaga o le vaega, ina ia i ai se aoga paleni hydrophilic-lipophilic talafeagai, ma se vevela-tali 2-hydroxy-3-butoxypropyl hydroxyethyl cellulose (HBPEC) ua saunia;ua saunia se meatotino e tali atu i le vevela O mea faigaluega e fa'avae i luga ole cellulose e maua ai se auala fou mo le fa'aogaina o mea aoga i totonu o vaega o le fa'asa'olotoina o vaila'au ma le biology.

Chen Yangming ma isi na faʻaaogaina le hydroxyethyl cellulose e avea o se mea mata, ma i le isopropanol solution system, faʻaopoopoina se vaega itiiti o Na2B4O7 i le reactant mo tali tutusa e saunia ai le eter hydroxyethyl carboxymethyl cellulose fefiloi.O le oloa e vave i le vai, ma O le viscosity e mautu.

Fa'aaoga e Wang Peng le cotton fa'amamāina fa'anatura e pei o le mea mata'utia, ma fa'aaogaina se la'asaga e tasi le fa'agasologa o le etherification e maua ai le carboxymethyl hydroxypropyl cellulose ma le tali tutusa, maualuga viscosity, fa'ato'aga lelei ma le masima e ala i le alkalization ma le etherification reactions Compound eter.I le faʻaaogaina o le tasi-laasaga etherification process, o le gaosiga o le carboxymethyl hydroxypropyl cellulose o loʻo i ai le malosi o le masima, teteʻe o le acid ma le solubility.E ala i le suia o le aofaʻi o le propylene oxide ma le chloroacetic acid, e mafai ona saunia oloa e eseese carboxymethyl ma hydroxypropyl.O faʻaiʻuga o suʻega o loʻo faʻaalia ai o le carboxymethyl hydroxypropyl cellulose o loʻo gaosia e le tasi-laasaga auala o loʻo i ai se taamilosaga puupuu o le gaosiga, maualalo le faʻaaogaina o le solvent, ma o le oloa e sili ona tetee atu i masima monovalent ma divalent ma le malosi o le acid resistance.Pe a faatusatusa i isi oloa ether cellulose, e sili atu le malosi o le tauvaga i le fanua o meaʻai ma suʻesuʻega suauʻu.

Hydroxypropylmethylcellulose (HPMC) o le ituaiga sili ona lelei ma sili ona lelei i totonu o ituaiga uma o cellulose, ma o se sui masani foi o fefaʻatauaʻiga i totonu o ethers fefiloi.I le 1927, o le hydroxypropylmethylcellulose (HPMC) na faʻapipiʻiina lelei ma faʻaesea.I le 1938, na iloa ai e le Dow Chemical Co. o le Iunaite Setete le gaosiga o fale gaosi oloa o le methyl cellulose ma fausia ai le faailoga lauiloa lauiloa "Methocel".O le gaosiga o pisinisi tetele o le hydroxypropyl methylcellulose na amata i le Iunaite Setete i le 1948. O le gaosiga o le gaosiga o le HPMC e mafai ona vaevaeina i ni vaega se lua: metotia o le vaega o le kesi ma le auala o le vai.I le taimi nei, o atunuʻu atinaʻe e pei o Europa, Amerika ma Iapani o loʻo faʻaaogaina le faʻagasologa o le kesi, ma o le gaosiga i totonu o le atunuʻu o le HPMC e faʻavae i luga o le faʻagasologa o le vai.

O Zhang Shuangjian ma isi na faʻamamaina le paʻu o le cotton e pei o mea mata, alkalized i le sodium hydroxide i le tali solvent medium toluene ma le isopropanol, faʻamalosia i le etherifying agent propylene oxide ma le methyl chloride, faʻaalia ma saunia se ituaiga vave hydroxypropyl methyl alcohol base cellulose eter.

 

3. Vaaiga

O le cellulose ose vaila'au taua ma vaila'au mata'utia e mauoa i puna'oa, lanu meamata ma fa'alelei le si'osi'omaga, ma fa'afouina.O mea e maua mai i le cellulose etherification modification e sili ona lelei le faʻatinoga, lautele o faʻaoga ma faʻaoga lelei aʻafiaga, ma faʻafetaui manaʻoga o le tamaoaiga o le atunuʻu i se tulaga tele.Ma o manaʻoga o le atinaʻeina o agafesootai, faʻatasi ai ma le faʻaauauina o tekinolosi ma le faʻataunuʻuina o pisinisi i le lumanaʻi, pe afai e mafai ona sili atu le faʻaogaina o mea faʻapipiʻi ma metotia faʻaogaina o cellulose derivatives, o le a sili atu ona faʻaaogaina atoatoa ma iloa ai se lautele lautele o talosaga. Taua.

 

 


Taimi meli: Ian-06-2023
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