Ka seretse se kopantsoeng se itokiselitseng, palo ea tlatsetso ea cellulose ether e tlase haholo, empa e ka ntlafatsa haholo ts'ebetso ea seretse se metsi, 'me ke tlatsetso e kholo e amang ts'ebetso ea kaho ea seretse.Khetho e utloahalang ea li-cellulose ethers tsa mefuta e sa tšoaneng, li-viscosities tse fapaneng, boholo bo fapaneng ba likaroloana, likhato tse fapaneng tsa viscosity le chelete e eketsehileng e tla ba le phello e ntle ntlafatsong ea ts'ebetso ea seretse se omeletseng sa phofo.Hajoale, liretse tse ngata tsa masonry le plastering li na le ts'ebetso e mpe ea ho boloka metsi, 'me seretse sa metsi se tla arohana kamora metsotso e seng mekae ea ho ema.Ho boloka metsi ke ts'ebetso ea bohlokoa ea methyl cellulose ether, hape ke ts'ebetso eo bahlahisi ba bangata ba seretse se ommeng malapeng, haholo-holo ba libakeng tse ka boroa tse nang le mocheso o phahameng, ba e ela hloko.Lintlha tse amang phello ea ho boloka metsi ea seretse sa motsoako o omileng li kenyelletsa palo ea MC e ekelitsoeng, viscosity ea MC, botle ba likaroloana le mocheso oa tikoloho ea tšebeliso.
1. Khopolo
Cellulose ether ke polymer ea maiketsetso e entsoeng ka selulose ea tlhaho ka phetoho ea lik'hemik'hale.Cellulose ether e tsoa ho cellulose ea tlhaho.Tlhahiso ea cellulose ether e fapane le li-polymers tsa maiketsetso.Thepa ea eona ea mantlha ke cellulose, motsoako oa tlhaho oa polymer.Ka lebaka la ho khetheha ha sebopeho sa cellulose ea tlhaho, selulose ka boeona ha e na bokhoni ba ho itšoara ka li-etherification agents.Leha ho le joalo, ka mor'a ho phekoloa ha moemeli oa ho ruruha, maqhama a matla a hydrogen pakeng tsa liketane tsa molek'hule le liketane li senyeha, 'me ho lokolloa ka mafolofolo ha sehlopha sa hydroxyl ho fetoha selulose e sebetsang ea alkali.Fumana ether ea cellulose.
Thepa ea cellulose ethers e itšetlehile ka mofuta, palo le kabo ea li-substituent.Ho hlophisoa ha cellulose ethers ho boetse ho ipapisitse le mofuta oa li-substituent, tekanyo ea etherification, solubility le thepa e amanang le kopo.Ho ea ka mofuta oa li-substituents ka ketane ea molek'hule, e ka aroloa ka monoether le ether e tsoakiloeng.MC eo re tloaetseng ho e sebelisa ke monoether, 'me HPMC ke ether e tsoakiloeng.Methyl cellulose ether MC ke sehlahisoa ka mor'a hore sehlopha sa hydroxyl se karolong ea tsoekere ea cellulose ea tlhaho e nkeloe sebaka ke methoxy.Ke sehlahisoa se fumanoang ka ho kenya karolo ea sehlopha sa hydroxyl sebakeng sa sehlopha ka sehlopha sa methoxy le karolo e 'ngoe ka sehlopha sa hydroxypropyl.Foromo ea sebopeho ke [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethyl methyl cellulose ether HEMC, ena ke mefuta e meholo e sebelisoang haholo le e rekisoang' marakeng.
Mabapi le solubility, e ka aroloa ka ionic le non-ionic.Li-ether tse qhibilihang ka metsing tseo e seng tsa ionic cellulose ethers haholo-holo li entsoe ka lihlopha tse peli tsa alkyl ethers le hydroxyalkyl ethers.Ionic CMC e sebelisoa haholo ho li-detergents tsa maiketsetso, khatiso ea masela le ho daea, ho hlahloba lijo le oli.Non-ionic MC, HPMC, HEMC, joalo-joalo li sebelisoa haholo-holo ka thepa ea kaho, liaparo tsa latex, meriana, lik'hemik'hale tsa letsatsi le letsatsi, joalo-joalo E sebelisoa e le motenya, moemeli oa ho boloka metsi, stabilizer, dispersant le moemeli oa ho etsa filimi.
Ea bobeli, ho boloka metsi a cellulose ether
Ho boloka metsi a cellulose ether: Ha ho etsoa thepa ea mohaho, haholo-holo seretse sa phofo se omeletseng, cellulose ether e phetha karolo e ke keng ea nkeloa sebaka, haholo-holo tlhahiso ea seretse se khethehileng (seretse se fetotsoeng), ke karolo ea bohlokoa le ea bohlokoa .
Karolo ea bohlokoa ea selulose e qhibilihang ka metsing ka seretse e na le likarolo tse tharo, e 'ngoe ke bokhoni bo babatsehang ba ho boloka metsi, e' ngoe ke tšusumetso ea ho lumellana le thixotropy ea seretse, 'me ea boraro ke ho sebelisana le samente.Phello ea ho boloka metsi ea cellulose ether e itšetlehile ka ho kenngoa ha metsi a lera la motheo, sebopeho sa seretse, botenya ba lera la seretse, tlhokahalo ea metsi ea seretse, le nako ea ho beha thepa.Ho boloka metsi a cellulose ether ka boeona ho tsoa ho solubility le dehydration ea cellulose ether ka boeona.Joalokaha bohle re tseba, le hoja ketane ea molek'hule ea cellulose e na le palo e kholo ea lihlopha tsa OH tse nang le metsi a mangata haholo, ha e qhibilihe ka metsing, hobane sebopeho sa cellulose se na le tekanyo e phahameng ea crystallinity.
Bokhoni ba hydration ba lihlopha tsa hydroxyl feela ha boa lekana ho koahela litlamo tse matla tsa hydrogen le matla a van der Waals pakeng tsa limolek'hule.Ka hona, e ruruha feela empa ha e qhibilihe ka metsing.Ha substituent e hlahiswa ka ketane ea limolek'hule, e seng feela substituent timetsa ketane ea haedrojene, empa hape interchain hydrogen tlamo timetsoa ka lebaka la wedging ea substituent pakeng tsa liketane tse haufi.Ha sebaka se seng se le seholo, sebaka se pakeng tsa limolek'hule se ba seholoanyane.Bohole bo boholo.Phello e kholoanyane ea ho senya likamano tsa hydrogen, cellulose ether e fetoha metsi a qhibilihang ka mor'a hore lesela la cellulose le atolohe 'me tharollo e kene, e etsa tharollo e phahameng ea viscosity.Ha mocheso o phahama, hydration ea polymer e fokola, 'me metsi a pakeng tsa liketane a lelekoa.Ha phello ea ho felloa ke metsi e lekaneng, limolek'hule li qala ho bokellana, ho etsa gel ea sebopeho sa marang-rang a mararo le ho phuthoa.
Lintlha tse amang ho bolokoa ha seretse li kenyelletsa cellulose ether viscosity, palo ea tlatsetso, botle ba likaroloana le mocheso oa tšebeliso:
Ha ho na le viscosity e kholo ea cellulose ether, ho na le ts'ebetso e ntle ea ho boloka metsi.Viscosity ke karolo ea bohlokoa ea ts'ebetso ea MC.Hajoale, bahlahisi ba fapaneng ba MC ba sebelisa mekhoa le lisebelisoa tse fapaneng ho lekanya viscosity ea MC.Mekhoa e ka sehloohong ke Haake Rotovisko, Hoppler, Ubbelohde le Brookfield.Bakeng sa sehlahisoa se le seng, liphetho tsa viscosity tse lekantsoeng ka mekhoa e fapaneng li fapane haholo, 'me tse ling li bile li na le phapang e habeli.Ka hona, ha ho bapisoa viscosity, e tlameha ho etsoa lipakeng tsa mekhoa e tšoanang ea liteko, ho kenyelletsa mocheso, rotor, jj.
Ha re bua ka kakaretso, ha viscosity e phahame, phello e ntle ea ho boloka metsi.Leha ho le joalo, ha viscosity e phahame le boima ba limolek'hule tsa MC, ho fokotseha ho lekanang le ho qhibiliha ha eona ho tla ba le tšusumetso e mpe ho matla le ts'ebetso ea kaho ea seretse.Ha li-viscosity li phahame, ho hlakile haholoanyane phello e teteaneng holim'a seretse, empa ha e lekane ka ho toba.Ha li-viscosity li phahame, seretse se metsi se tla ba le viscous haholoanyane, ke hore, nakong ea kaho, se bonahatsoa e le ho khomarela sekoti le ho khomarela holimo ho substrate.Empa ha ho na thuso ho eketsa matla a sebopeho sa seretse se metsi ka boeona.Nakong ea kaho, ts'ebetso ea anti-sag ha e hlake.Ho fapana le hoo, li-viscosity tse ling tse mahareng le tse tlase empa tse fetotsoeng tsa methyl cellulose ethers li na le ts'ebetso e ntle haholo ho ntlafatsa matla a sebopeho sa seretse se metsi.
Ha palo e kholo ea ether ea cellulose e kentsoeng seretseng, e ntlafatsa ts'ebetso ea ho boloka metsi, 'me ha ponahalo ea viscosity e phahame, e ntlafatsa ts'ebetso ea ho boloka metsi.
Mabapi le boholo ba karoloana, ha karoloana e le ntle, ho boloka metsi ho betere.Ka mor'a hore likaroloana tse kholo tsa cellulose ether li kopane le metsi, bokaholimo bo qhibiliha hang-hang 'me bo etse gel ho phuthela thepa ho thibela limolek'hule tsa metsi ho tsoela pele ho kenella.Ka nako e 'ngoe ha e khone ho qhalakanngoa le ho qhibiliha ka mokhoa o ts'oanang le ka mor'a ho sisinyeha ha nako e telele, ho etsa tharollo e koahetsoeng ke maru kapa agglomeration.E ama haholo ho boloka metsi a cellulose ether, 'me ho qhibiliha ke e' ngoe ea lintlha tsa ho khetha cellulose ether.
Fineness hape ke index ea bohlokoa ea ts'ebetso ea methyl cellulose ether.MC e sebelisoang bakeng sa seretse sa phofo e omeletseng e hlokeha hore e be phofo, e nang le metsi a tlaase, 'me botle bo boetse bo hloka 20% ~ 60% ea boholo ba likaroloana ho ba ka tlase ho 63um.Bonolo bo ama ho qhibiliha ha methyl cellulose ether.Coarse MC hangata ke granular, 'me ho bonolo ho qhibiliha ka metsing ntle le agglomeration, empa sekhahla sa ho qhibiliha se lieha haholo, kahoo ha sea lokela ho sebelisoa ka seretse se omeletseng sa phofo.Ka seretse sa phofo se omeletseng, MC e hasane har'a lisebelisoa tsa samente tse kang aggregate, filler e ntle le samente, 'me phofo e lekaneng feela e ka qoba methyl cellulose ether agglomeration ha e kopanya le metsi.Ha MC e eketsoa ka metsi ho qhaqha li-agglomerate, ho thata haholo ho qhala le ho qhaqha.
Coarse fineness ea MC ha e senya feela, empa hape e fokotsa matla a sebaka sa seretse.Ha seretse se joalo sa phofo se ommeng se sebelisoa sebakeng se seholo, lebelo la ho folisa la seretse se omileng sa sebaka seo se tla fokotseha haholo, 'me mapetsong a tla hlaha ka lebaka la linako tse fapaneng tsa ho folisa.Bakeng sa seretse se fafalitsoeng se nang le mohaho oa mechine, tlhokahalo ea fineness e phahame ka lebaka la nako e khutšoanyane ea ho kopanya.
Botle ba MC bo boetse bo na le phello e itseng ho bolokeng metsi ha eona.Ka kakaretso, bakeng sa li-ether tsa methyl cellulose tse nang le viscosity e tšoanang empa botle bo fapaneng, tlas'a tekanyo e tšoanang ea tlatsetso, ho ntlafala ho hoholo ho ka ba molemo ho boloka metsi.
Ho boloka metsi a MC ho boetse ho amana le mocheso o sebelisoang, 'me ho boloka metsi a methyl cellulose ether ho fokotseha ka ho eketseha ha mocheso.Leha ho le joalo, lits'ebetsong tsa 'nete, seretse sa phofo se omeletseng se sebelisoa hangata ho li-substrates tse chesang ka mocheso o phahameng (ho feta likhato tse 40) libakeng tse ngata, joalo ka bokantle ba lebota la putty plaster tlas'a letsatsi lehlabula, hangata bo potlakisang Pholiso ea samente le ho thatafala ha seretse. seretse sa phofo se ommeng.Ho fokotseha ha sekhahla sa ho boloka metsi ho lebisa boikutlong bo totobetseng ba hore bobeli ba ho sebetsa le ho hanyetsa ho phatloha ho ameha, 'me ho bohlokoa haholo ho fokotsa tšusumetso ea maemo a mocheso tlas'a boemo bona.
Le hoja li-additives tsa methyl hydroxyethyl cellulose ether hona joale li nkoa e le tsona tse ka pele ho nts'etsopele ea theknoloji, ho itšetleha ha bona ka mocheso ho ntse ho tla lebisa ho fokolisa ts'ebetso ea seretse se omeletseng sa phofo.Le hoja palo ea methyl hydroxyethyl cellulose e eketsehile (formula ea lehlabula), ho sebetsa le ho hanyetsa ha crack ho ntse ho sa khone ho finyella litlhoko tsa tšebeliso.Ka phekolo e khethehileng ho MC, joalo ka ho eketsa tekanyo ea etherification, joalo-joalo, phello ea ho boloka metsi e ka bolokoa ka mocheso o phahameng, e le hore e ka fana ka ts'ebetso e ntlafetseng tlas'a maemo a thata.
3. Thickening le Thixotropy ea Cellulose Ether
Thickening le thixotropy ea cellulose ether: Mosebetsi oa bobeli oa cellulose ether-thickening effect e itšetlehile ka: tekanyo ea polymerization ea cellulose ether, mahloriso a tharollo, sekhahla sa shear, mocheso le maemo a mang.Thepa ea gelling ea tharollo e ikhethile ho alkyl cellulose le li-derivatives tsa eona tse fetotsoeng.Thepa ea gelation e amana le tekanyo ea ho fetola, mahloriso a tharollo le li-additives.Bakeng sa li-derivatives tse fetotsoeng tsa hydroxyalkyl, thepa ea gel e boetse e amana le boemo ba phetoho ea hydroxyalkyl.Bakeng sa viscosity tlaase MC le HPMC, 10% -15% tharollo ka lokisoa, mahareng viscosity MC le HPMC ka lokisoa 5% -10% tharollo, ha phahameng viscosity MC le HPMC ka feela lokisetsa 2% -3% tharollo, 'me Hangata. sehlopha sa viscosity sa cellulose ether se boetse se hlophisoa ka tharollo ea 1% -2%.
Limolek'hule tse phahameng tsa cellulose ether li na le bokhoni bo phahameng ba ho tiea.Tharollong e tšoanang ea mahloriso, li-polymer tse nang le boima bo fapaneng ba limolek'hule li na le li-viscosity tse fapaneng.Tekanyo e phahameng.Sepheo sa viscosity se ka finyelloa feela ka ho eketsa palo e kholo ea boima bo tlaase ba molek'hule cellulose ether.Viscosity ea eona ha e itšetlehe haholo ka sekhahla sa ho kuta, 'me viscosity e phahameng e fihla ho viscosity e reriloeng,' me palo e hlokahalang ea tlatsetso e nyane, 'me viscosity e ipapisitse le katleho e kholo.Ka hona, ho finyella ts'ebetso e itseng, palo e itseng ea cellulose ether (ho tsepamisa maikutlo ho tharollo) le viscosity ea tharollo e tlameha ho tiisetsoa.Mocheso oa mocheso oa gel oa tharollo o boetse o fokotseha ka mokhoa o ts'oanang le ho eketseha ha motsoako oa tharollo, le li-gel ka mocheso oa motsoako ka mor'a hore li fihle boemong bo itseng.Motsoako oa gelling oa HPMC o batla o phahame mocheso oa kamore.
Ho lumellana ho ka boela ha fetoloa ka ho khetha boholo ba likaroloana le ho khetha li-cellulose ethers tse nang le likhato tse fapaneng tsa phetoho.Seo ho thoeng ke phetoho ke ho hlahisa tekanyo e itseng ea ho fetola lihlopha tsa hydroxyalkyl holim'a sebopeho sa skeleton sa MC.Ka ho fetola litekanyetso tse lekanyelitsoeng tsa phapanyetso ea li-substitute tse peli, ke hore, DS le ms e amanang le phapanyetso ea boleng ba lihlopha tsa methoxy le hydroxyalkyl tseo re li buang hangata.Litlhoko tse fapaneng tsa ts'ebetso ea cellulose ether li ka fumanoa ka ho fetola litekanyetso tse amanang le tse ling tse peli.
Kamano pakeng tsa ho tsitsa le ho fetola: ho eketsoa ha cellulose ether ho ama tšebeliso ea metsi ea seretse, ho fetola tekanyo ea metsi-binder ea metsi le samente ke phello e matla, e phahameng ea litekanyetso, ho sebelisoa ha metsi ho feta.
Li-cellulose ethers tse sebelisoang ka thepa ea mohaho ea phofo li tlameha ho qhibiliha ka potlako metsing a batang 'me li fane ka mokhoa o loketseng oa tsamaiso.Haeba ho fanoa ka sekhahla se itseng sa ho kuta, se ntse se fetoha flocculent le colloidal block, e leng sehlahisoa sa boleng bo tlaase kapa se tlaase.
Ho boetse ho na le kamano e ntle pakeng tsa ho lumellana ha pente ea samente le tekanyo ea cellulose ether.Cellulose ether e ka eketsa viscosity ea seretse haholo.Ha tekanyo e le kholoanyane, phello e totobetse haholoanyane.High-viscosity cellulose ether aqueous solution e na le thixotropy e phahameng, eo hape e leng tšobotsi e kholo ea cellulose ether.Litharollo tsa metsi tsa MC polymers hangata li na le pseudoplastic le non-thixotropic fluidity ka tlase ho mocheso oa bona oa gel, empa thepa ea phallo ea Newtonian ka litheko tse tlase tsa ho kuta.Pseudoplasticity e eketseha ka boima ba molek'hule kapa bongata ba cellulose ether, ho sa tsotelehe mofuta oa ntho e nkeloang sebaka le tekanyo ea ho e nkela sebaka.Ka hona, li-cellulose ethers tsa sehlopha se tšoanang sa viscosity, ho sa tsotellehe MC, HPMC, HEMC, li tla lula li bontša litšobotsi tse tšoanang tsa rheological hafeela mahloriso le mocheso li bolokiloe kamehla.
Li-gels tsa mohaho li thehoa ha mocheso o phahama, 'me ho phalla ha thixotropic haholo ho etsahala.Mahloriso a phahameng le a tlaase a viscosity cellulose ethers a bontša thixotropy esita le ka tlase ho mocheso oa gel.Thepa ena e na le molemo o moholo ho lokisoeng ha maemo le ho putlama ha kaho ea seretse sa moaho.Hoa hlokahala ho hlalosa mona hore ho phahama ha viscosity ea cellulose ether, ho boloka metsi ho ntlafala, empa ho phahama ha viscosity, ho phahamisa boima ba molek'hule ea cellulose ether, le ho fokotseha ho tšoanang ha ho qhibiliha ha eona, ho nang le phello e mpe. mabapi le mahloriso a seretse le ts'ebetso ea kaho.Ha li-viscosity li phahame, ho hlakile haholoanyane phello e teteaneng holim'a seretse, empa ha e lekane ka ho feletseng.Li-viscosity tse ling tse mahareng le tse tlase, empa cellulose ether e fetotsoeng e na le ts'ebetso e ntle ho ntlafatsa matla a sebopeho sa seretse se metsi.Ka ho eketseha ha viscosity, ho boloka metsi a cellulose ether ho ntlafala.4. Ho lieha ha cellulose ether
Ho lieha ha cellulose ether: Mosebetsi oa boraro oa cellulose ether ke ho liehisa ts'ebetso ea hydration ea samente.Cellulose ether e fana ka seretse se nang le lisebelisoa tse fapaneng tse molemo, hape e fokotsa mocheso oa pele oa hydration oa samente le ho liehisa ts'ebetso ea hydration e matla ea samente.Sena ha se monate bakeng sa tšebeliso ea seretse libakeng tse batang.Phello ena ea ho lieha e bakoa ke ho ata ha limolek'hule tsa cellulose ether lihlahisoa tsa hydration tse kang CSH le ca(OH)2.Ka lebaka la ho eketseha ha viscosity ea tharollo ea pore, cellulose ether e fokotsa ho tsamaea ha li-ion ka tharollo, kahoo e liehisa ts'ebetso ea hydration.
Nako ea poso: Feb-04-2023