Cellulose ether izwi rinowanzoreva nhevedzano yezvigadzirwa zvinogadzirwa nekuita kwealkali cellulose uye etherifying agent mune mamwe mamiriro. Alkali cellulose inotsiviwa nema etherifying agents akasiyana kuti awane akasiyana cellulose ethers. Zvinoenderana neiyo ionization yezvinhu zvinotsiva, cellulose ethers inogona kukamurwa kuita mapoka maviri: ionic (senge carboxymethyl cellulose) uye nonionic (senge methyl cellulose). Zvinoenderana nerudzi rweinotsiva, cellulose ether inogona kukamurwa kuita monoether (senge methyl cellulose) uye yakasanganiswa ether (senge hydroxypropyl methyl cellulose). Zvinoenderana nekunyungudika kwakasiyana, inogona kukamurwa kuita kunyungudika kwemvura (senge hydroxyethyl cellulose) uye organic solvent solubility (senge ethyl cellulose). Dry-mixed dhaka inonyanya kunyungudika mvura selulosi, uye mvura-soluble cellulose yakakamurwa kuita yekukurumidza mhando uye pamusoro-yakagadziriswa kunonoka-kuparara mhando.
Maitiro ekuita kwe cellulose ether mudhaka ndeaya anotevera:
(1) Mushure mekunge cellulose ether mudhaka yanyungudutswa mumvura, kugovaniswa kwakanaka uye kwakafanana kwezvinhu esimende muhurongwa kunovimbiswa nekuda kwebasa repamusoro, uye cellulose ether, senge inodzivirira, "inoputira" yakasimba. zvimedu uye A layer yefirimu yekuzora inoumbwa pane yayo yekunze, iyo inoita kuti dhaka rigadzikane, uye zvakare inovandudza fluidity yedhaka panguva yekusanganiswa uye kutsetseka kwekuvaka.
(2) Nekuda kwehunhu hwayo hwemamorekuru, iyo cellulose ether solution inoita kuti mwando uri mudhaka usave nyore kurasikirwa, uye zvishoma nezvishoma inouburitsa kwenguva yakareba, ichipa dhaka nekuchengetedza mvura zvakanaka uye kushanda.
1. Methylcellulose: (MC)
Mushure mekunge donje rakanatswa ragadziriswa nealkali, cellulose ether inogadzirwa kuburikidza neyakatevedzana maitiro ane methane chloride se etherification agent. Kazhinji, dhigirii rekutsiva i1.6 ~ 2.0, uye kunyungudika kwakasiyanawo nemadhigirii akasiyana ekutsiva. Iyo ndeye isiri-ionic cellulose ether.
(1) Methylcellulose inonyungudika mumvura inotonhora, uye zvichave zvakaoma kunyungudika mumvura inopisa. Mushonga wayo une aqueous wakanyatsogadzikana muhupamhi hwepH = 3 ~ 12. Iine kuwirirana kwakanaka ne starch, guar gum, nezvimwewo uye akawanda ma surfactants. Kana tembiricha inosvika tembiricha yegelation, gelation inoitika.
(2) Kuchengetwa kwemvura kwemethyl cellulose kunoenderana nehuwandu hwayo hwekuwedzera, viscosity, particle fineness uye dissolution rate. Kazhinji, kana huwandu hwekuwedzera hwakakura, hunyoro hudiki, uye viscosity yakakura, mwero wekuchengetedza mvura wakakwira. Pakati pavo, huwandu hwekuwedzera hune simba guru pahuwandu hwekuchengetedza mvura, uye chiyero che viscosity hachina kuenzana zvakananga nehuwandu hwekuchengetedza mvura. Mwero wekunyungudika unonyanya kuenderana nehuwandu hwekugadziriswa kwepasi kwe cellulose particles uye particle fineness. Pakati pema cellulose ethers ari pamusoro, methyl cellulose uye hydroxypropyl methyl cellulose vane mwero wepamusoro wekuchengetedza mvura.
(3) Shanduko mutembiricha ichakanganisa zvakanyanya mwero wekuchengetedza mvura yemethyl cellulose. Kazhinji, kukwirisa tembiricha, kunowedzera kuchengetedzeka kwemvura. Kana tembiricha yevhu ichipfuura 40 ° C, kuchengetwa kwemvura kwemethyl cellulose kuchaderedzwa zvakanyanya, kunokanganisa zvakanyanya kuvakwa kwedhaka.
(4) Methyl cellulose ine simba guru pakuvaka uye kubatana kwedhaka. “Kunamira” pano kunoreva simba rekubatanidza rinonzwikwa pakati pemudziyo wemudziyo wekushandisa nemadziro emadziro, ndiko kuti, kugerwa kwedhaka. Kunamatira kwakakwirira, kupikisa kweshear kwevhu kwakakura, uye simba rinodiwa nevashandi vari mukugadzirisa kushandiswa kwakakurawo, uye kushanda kwekuvaka kwedhaka kwakashata. Iko kubatana kwemethyl cellulose iri padanho repakati mune cellulose ether zvigadzirwa.
2. Hydroxypropyl methyl cellulose (HPMC):
Hydroxypropyl methylcellulose imhando ye cellulose iyo kubuda kwayo uye kushandiswa kwave kuwedzera nekukurumidza mumakore achangopfuura. Iyo isiri-ionic cellulose yakasanganiswa ether yakagadzirwa kubva kudonje rakanatswa mushure me alkalization, uchishandisa propylene oxide uye methyl chloride se etherification agent, kuburikidza neakatevedzana maitiro. Dhigirii rekutsiva kazhinji 1.2 ~ 2.0. Zvimiro zvayo zvinosiyana zvichienderana nereshiyo yemethoxyl yemukati kune hydroxypropyl yemukati.
(1) Hydroxypropyl methylcellulose inonyungudika nyore nyore mumvura inotonhora, uye ichasangana nematambudziko mukunyungudika mumvura inopisa. Asi tembiricha yayo yegelation mumvura inopisa yakanyanya kukwirira kupfuura yemethyl cellulose. Iyo solubility mumvura inotonhora zvakare yakagadziridzwa zvakanyanya kana ichienzaniswa nemethyl cellulose.
(2) Iyo viscosity yehydroxypropyl methylcellulose inoenderana nehuremu hwayo hwemamorekuru, uye iyo yakakura huremu hwemamorekuru, inokwirisa viscosity. Kupisa kunokanganisawo viscosity yayo, sezvo tembiricha inowedzera, viscosity inoderera. Nekudaro, pesvedzero yeayo high viscosity uye tembiricha yakaderera pane iyo yemethyl cellulose. Mushonga waro wakagadzikana kana wakachengetwa pakushambidzika kwekamuri.
(3) Kuchengetwa kwemvura kwehydroxypropyl methylcellulose kunoenderana nehuwandu hwayo hwekuwedzera, viscosity, nezvimwewo, uye chiyero chekuchengetedza mvura pasi peiyo imwechete yekuwedzera yakakwira kupfuura iyo yemethyl cellulose.
(4) Hydroxypropyl methylcellulose yakagadzikana kune asidhi uye alkali, uye mhinduro yayo yemvura yakanyatsogadzikana muhuwandu hwepH = 2 ~ 12. Caustic soda uye mvura yeraimu haina mhedzisiro pakuita kwayo, asi alkali inogona kukurumidzira kuparara kwayo uye kuwedzera zvishoma viscosity yayo. Hydroxypropyl methylcellulose yakagadzikana kune yakajairwa munyu, asi kana kusanganiswa kwemunyu munyu kwakakwira, viscosity yehydroxypropyl methylcellulose mhinduro inowedzera kuwedzera.
(5) Hydroxypropyl methylcellulose inogona kusanganiswa nemvura-soluble polymer compounds kuti iite yunifomu uye yakakwirira viscosity mhinduro. Zvakadai se polyvinyl doro, starch ether, muriwo gum, nezvimwe.
(6) Hydroxypropyl methylcellulose ine nani enzyme kuramba kupfuura methylcellulose, uye mukana we enzymatic degradation yemhinduro yayo yakaderera pane iyo yemethylcellulose.
(7) Iko kunamatira kwehydroxypropyl methylcellulose kukuvaka kwedhaka kwakakwira kupfuura iyo yemethylcellulose.
3. Hydroxyethyl cellulose (HEC):
Yakagadzirwa kubva mukotoni yakanatswa yakabatwa nealkali, uye yakaitwa ne ethylene oxide se etherification agent pamberi peacetone. Dhigirii rayo rekutsiva kazhinji 1.5 ~ 2.0. Iyo ine yakasimba hydrophilicity uye iri nyore kutora unyoro.
(1) Hydroxyethyl cellulose inonyungudika mumvura inotonhora, asi yakaoma kunyungudika mumvura inopisa. Mhinduro yaro yakagadzikana pakupisa kwepamusoro pasina gelling. Inogona kushandiswa kwenguva yakareba pasi pekushisa kwepamusoro mumatope, asi kuchengetedza kwayo mvura kwakaderera pane iyo yemethyl cellulose.
(2) Hydroxyethyl cellulose yakagadzikana kune general acid uye alkali. Alkali inogona kukurumidza kuparara kwayo uye zvishoma kuwedzera viscosity yayo. Kupararira kwayo mumvura kwakashata zvishoma kupfuura iyo yemethyl cellulose uye hydroxypropyl methyl cellulose. .
(3) Hydroxyethyl cellulose ine yakanaka anti-sag performance yedhaka, asi ine nguva yakareba yekudzosa simende.
(4) Kuita kwehydroxyethyl cellulose inogadzirwa nemamwe mabhizinesi epamba yakaderera zvakanyanya pane iyo yemethyl cellulose nekuda kweiyo yakakwira-mvura yemukati uye yakakwira madota.
4. Carboxymethyl cellulose (CMC):
Ionic cellulose ether inogadzirwa kubva kune yakasikwa fibers (donje, nezvimwewo) mushure mekurapa kwealkali, uchishandisa sodium monochloroacetate se etherification agent, uye ichiitwa nhevedzano yemaitiro ekurapwa. Dhigirii rekutsiva kazhinji 0.4 ~ 1.4, uye kuita kwayo kunokanganisa zvakanyanya nedhigirii rekutsiva.
(1) Carboxymethyl cellulose inowedzera hygroscopic, uye ichange iine mvura yakawanda kana yakachengetwa pasi pemamiriro ezvinhu.
(2) Carboxymethyl cellulose aqueous solution haizobudisi gel, uye viscosity inoderera nekuwedzera kwekushisa. Kana tembiricha inopfuura 50 ° C, viscosity haidzoreki.
(3) Kugadzikana kwayo kunokonzerwa zvikuru nePH. Kazhinji, inogona kushandiswa mune gypsum-based mortar, asi kwete musimende-based mortar. Kana yakanyanya alkaline, inorasikirwa neviscosity.
(4) Kuchengeta kwayo mvura kwakadzikira zvakanyanya kupfuura kwemethyl cellulose. Iyo ine mhedzisiro yekudzosera pane gypsum-based mortar uye inoderedza simba rayo. Nekudaro, mutengo wecarboxymethyl cellulose wakaderera zvakanyanya pane wemethyl cellulose.
Nguva yekutumira: Feb-27-2023