Mehaho e tloaelehileng ea tse pelili-cellulose ethersli fanoe ho Lipapiso 1.1 le 1.2. Morara o mong le o mong oa β-D-dehydrate oa molek'hule ea cellulose
Yuniti ea tsoekere (yuniti e pheta-phetoang ea cellulose) e nkeloa sebaka ke sehlopha se le seng sa ether se seng le se seng maemong a C(2), C(3) le C(6), ke hore ho fihla ho tse tharo.
sehlopha sa ether. Ka lebaka la boteng ba lihlopha tsa hydroxyl, li-cellulose macromolecules li na le li-intramolecular le intermolecular hydrogen bond, tseo ho leng thata ho li qhibiliha ka metsing.
'Me ho thata ho qhibiliha hoo e batlang e le lihlapolli tsohle tsa manyolo. Leha ho le joalo, ka mor'a etherification ea cellulose, lihlopha tsa ether li kenngoa ka har'a ketane ea limolek'hule,
Ka tsela ena, maqhama a haedrojene ka hare le pakeng tsa limolek'hule tsa selulose li senyeha, 'me hydrophilicity ea eona e boetse e ntlafatsoa, e le hore ho qhibiliha ha eona ho ka ntlafatsoa.
e ntlafetse haholo. Har'a tsona, Setšoantšo sa 1.1 ke sebopeho se akaretsang sa li-unit tse peli tsa anhydroglucose tsa cellulose ether molecular chain, R1-R6 = H.
kapa lintho tse nkeloang sebaka. 1.2 ke sekhechana sa ketane ea molek'hule ea carboxymethyl hydroxyethyl cellulose, tekanyo ea ho kenya sebaka sa carboxymethyl ke 0.5,4
Tekanyo ea sebaka sa hydroxyethyl ke 2.0, 'me degree ea molar substitution ke 3.0.
Bakeng sa sebaka se seng le se seng sa selulose, kakaretso ea palo ea etherification ea eona e ka hlalosoa e le tekanyo ea ho fetola (DS). e entsoeng ka likhoele
E ka bonoa ho tsoa sebopehong sa molek'hule ea mantlha hore tekanyo ea phetoho e tloha ho 0-3. Ka mantsoe a mang, selikalikoe se seng le se seng sa anhydroglucose unit ea cellulose
, palo e tloaelehileng ea lihlopha tsa hydroxyl tse nkeloang sebaka ke lihlopha tsa etherifying tsa etherifying agent. Ka lebaka la sehlopha sa hydroxyalkyl sa cellulose, e nkeloa sebaka
Etherification e lokela ho qalisoa bocha ho tsoa sehlopheng se secha sa mahala sa hydroxyl. Ka hona, tekanyo ea ho kenya sebaka sa mofuta ona oa cellulose ether e ka hlahisoa ka moles.
degree of substitution (MS). Ho thoeng ke "molar degree of substitution" e bonts'a palo ea etherifying e kenyellelitsoeng yuniti e 'ngoe le e 'ngoe ea anhydroglucose ea selulose.
Kakaretso ea boima ba li-reactants.
1 Sebopeho se akaretsang sa yuniti ea tsoekere
2 Likhechana tsa liketane tsa limolek'hule tsa cellulose ether
1.2.2 Ho aroloa ha cellulose ethers
Hore na li-cellulose ethers ke li-ether tse le 'ngoe kapa li-ether tse tsoakiloeng, thepa ea tsona e batla e fapane. Cellulose macromolecules
Haeba sehlopha sa hydroxyl sa selikalikoe sa yuniti se nkeloa sebaka ke sehlopha sa hydrophilic, sehlahisoa se ka ba le tekanyo e tlaase ea ho fetola tlas'a boemo ba boemo bo tlaase ba ho fetola.
E na le ho qhibiliha ho itseng ha metsi; haeba e nkeloa sebaka ke sehlopha sa hydrophobic, sehlahisoa se na le tekanyo e itseng ea ho fetola feela ha tekanyo ea ho kenya sebaka e lekanyelitsoe.
Lihlahisoa tse qhibilihang ka metsing, tse sa nkeloe sebaka ke cellulose etherification li ka kokomoha feela ka metsing, kapa tsa qhibiliha ka har'a litharollo tse sa tebang haholo tsa alkali.
bohareng.
Ho ea ka mefuta ea li-substitute, li-cellulose ethers li ka aroloa ka lihlopha tse tharo: lihlopha tsa alkyl, tse kang methyl cellulose, ethyl cellulose;
Hydroxyalkyls, joalo ka hydroxyethyl cellulose, hydroxypropyl cellulose; ba bang, tse kang carboxymethyl cellulose, joalo-joalo Haeba ionization
Classification, cellulose ethers e ka aroloa ka: ionic, joalo ka carboxymethyl cellulose; e seng ionic, joalo ka hydroxyethyl cellulose; kopanetsoe
mofuta, joalo ka hydroxyethyl carboxymethyl cellulose. Ho ea ka sehlopha sa solubility, selulose e ka aroloa ka: metsi a qhibilihang, joalo ka carboxymethyl cellulose,
Hydroxyethyl cellulose; e sa keneng metsi, joalo ka methyl cellulose, joalo-joalo.
1.2.3 Thepa le ts'ebeliso ea li-cellulose ethers
Cellulose ether ke mofuta oa sehlahisoa ka mor'a phetoho ea cellulose etherification, 'me cellulose ether e na le lintho tse ngata tsa bohlokoa haholo. joalo ka
E na le thepa e ntle ea ho etsa lifilimi; e le pente ea khatiso, e na le ho qhibiliha ha metsi hantle, thepa e teteaneng, ho boloka metsi le botsitso;
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Plain ether ha e na monko, ha e chefo, 'me e na le biocompatibility e ntle. Har'a tsona, carboxymethyl cellulose (CMC) e na le "industrial monosodium glutamate"
lebitso la bosoasoi.
1.2.3.1 Sebopeho sa lifilimi
Tekanyo ea etherification ea cellulose ether e na le tšusumetso e kholo linthong tsa eona tsa ho etsa lifilimi tse kang bokhoni ba ho etsa lifilimi le matla a ho kopanya. Cellulose ether
Ka lebaka la matla a eona a matle a mochine le ho lumellana hantle le li-resin tse sa tšoaneng, e ka sebelisoa lifiliming tsa polasetiki, li-adhesives le lisebelisoa tse ling.
ho lokisetsa lintho tse bonahalang.
1.2.3.2 Solubility
Ka lebaka la boteng ba lihlopha tse ngata tsa hydroxyl lesale la yuniti ea tsoekere e nang le oksijene, li-cellulose ethers li na le ho qhibiliha ha metsi ho betere. le
Ho itšetlehile ka sebaka sa cellulose ether le tekanyo ea ho fetola, ho boetse ho na le khetho e fapaneng bakeng sa metsoako ea manyolo.
1.2.3.3 Ho teteana
Cellulose ether e qhibiliha ka tharollo ea metsi ka mokhoa oa colloid, moo tekanyo ea polymerization ea cellulose ether e khethollang selulose.
Viscosity ea tharollo ea ether. Ho fapana le maro a Newtonian, viscosity ea litharollo tsa cellulose ether e fetoha ka matla a ho kuta, le
Ka lebaka la sebopeho sena sa macromolecules, viscosity ea tharollo e tla eketseha ka potlako ka ho eketseha ha lintho tse tiileng tsa cellulose ether, leha ho le joalo, viscosity ea tharollo.
Viscosity e boetse e fokotseha ka potlako ka mocheso o ntseng o eketseha [33].
1.2.3.4 Ho senyeha ha maemo
Tharollo ea cellulose ether e qhibilihisitsoeng metsing ka nako e itseng e tla holisa baktheria, ka hona e hlahise libaktheria tsa enzyme le ho senya karolo ea cellulose ether.
Li-unit tsa glucose tse haufi tse sa nkeloang sebaka, ka hona li fokotsa boima ba molek'hule ea macromolecule. Ka hona, li-cellulose ethers
Ho boloka litharollo tse nang le metsi a mangata ho hloka ho eketsoa ha li-preservatives tse itseng.
Ntle le moo, li-cellulose ethers li na le lisebelisoa tse ling tse ngata tse ikhethang joalo ka ts'ebetso ea holim'a metsi, ts'ebetso ea ionic, botsitso ba foam le litlatsetso.
ketso ea gel. Ka lebaka la thepa ena, li-cellulose ethers li sebelisoa ka masela, ho etsa pampiri, li-detergents, litlolo, lijo, meriana,
E sebelisoa haholo mafapheng a mangata.
1.3 Selelekela sa ho lema thepa e tala
Ho latela kakaretso ea 1.2 cellulose ether, ho ka bonoa hore thepa e tala bakeng sa ho lokisoa ha cellulose ether ke haholo-holo k'hothone cellulose, 'me e' ngoe ea litaba tsa sehlooho sena.
Ke ho sebelisa cellulose e ntšitsoeng linthong tse tala tsa semela ho nka sebaka sa cellulose ea k'hothone ho lokisa cellulose ether. Se latelang ke kenyelletso e khutšoane ea semela
thepa.
Ha lisebelisoa tse tloaelehileng tse kang oli, mashala le khase ea tlhaho li ntse li fokotseha, nts'etsopele ea lihlahisoa tse fapaneng tse thehiloeng ho tsona, tse kang li-synthetic fibers le lifilimi tsa fiber, le tsona li tla thibeloa ka ho eketsehileng. Ka nts'etsopele e tsoelang pele ea sechaba le linaha lefatšeng ka bophara (haholo-holo
Ke naha e tsoetseng pele) e elang hloko haholo bothata ba tšilafalo ea tikoloho. Selulose ea tlhaho e na le biodegradability le khokahano ea tikoloho.
Butle-butle e tla fetoha mohloli o ka sehloohong oa lisebelisoa tsa fiber.
Nako ea poso: Sep-26-2022