Cellulose ether i polymer yakagadzirwa kubva kune yakasikwa cellulose kuburikidza nekugadzirisa kemikari.Cellulose ether inobva kune yakasikwa cellulose.Kugadzirwa kwe cellulose ether kwakasiyana nemapolymer ekugadzira.Yayo inonyanya kukosha ndeye cellulose, yakasikwa polymer musanganiswa.Nekuda kwekusarudzika kwechisikigo cellulose chimiro, iyo cellulose pachayo haina kugona kuita ne etherification agents.Zvisinei, mushure mekurapwa kwechirwere chekuzvimba, zvisungo zvakasimba zvehydrogen pakati pemaketani emaketani nemaketani zvinoparadzwa, uye kusunungurwa kunoshingaira kweboka rehydroxyl kunova reactive alkali cellulose.Wana cellulose ether.
Zvinhu zve cellulose ethers zvinoenderana nerudzi, nhamba uye kugovera kwezvinotsiva.Kurongeka kwe cellulose ethers zvakare kwakavakirwa pamhando yezvinotsiva, dhigirii reetherification, solubility uye zvine chekuita nekushandisa zvivakwa.Zvinoenderana nerudzi rwezvinotsiva pane molecular cheni, inogona kukamurwa kuita monoether uye yakasanganiswa ether.Iyo MC yatinowanzo shandisa ndeye monoether, uye iyo HPMC yakasanganiswa ether.Methyl cellulose ether MC ndicho chigadzirwa mushure meboka re hydroxyl pane glucose unit ye natural cellulose inotsiviwa ne methoxy.Icho chigadzirwa chinowanikwa nekutsiva chikamu cheboka rehydroxyl payuniti neboka remethoxy uye chimwe chikamu neboka rehydroxypropyl.Iyo yemaitiro fomula ndeye [C6H7O2(OH)3-mn(OCH3)m[OCH2CH(OH)CH3]n]x Hydroxyethyl methyl cellulose ether HEMC, aya ndiwo makuru emhando anoshandiswa zvakanyanya uye anotengeswa pamusika.
Panyaya yekunyungudika, inogona kukamurwa kuita ionic uye isiri-ionic.Mvura inonyungudika isiri-ionic cellulose ethers inonyanya kuumbwa maviri akatevedzana ealkyl ethers uye hydroxyalkyl ethers.Ionic CMC inonyanya kushandiswa mukugadzira dhizaini, machira kudhinda uye dhayi, chikafu uye kuongorora mafuta.Non-ionic MC, HPMC, HEMC, nezvimwewo zvinonyanya kushandiswa mukuvaka zvinhu, latex coatings, mishonga, makemikari ezuva nezuva, etc. Inoshandiswa seyakasviba, mvura inochengetedza agent, stabilizer, dispersant uye film forming agent.
Kuchengetwa kwemvura ye cellulose ether
Mukugadzirwa kwezvinhu zvekuvaka, kunyanya yakaoma-yakasanganiswa dhaka, cellulose ether inoita basa risingadzokerike, kunyanya mukugadzirwa kwedhaka rakakosha (modified mortar), chinhu chakakosha uye chakakosha chikamu.
Basa rakakosha remvura-soluble cellulose ether mudhaka rinonyanya kuve nemativi matatu, imwe yakanakisa kuchengetedza mvura, imwe isimba pakuenderana uye thixotropy wedhaka, uye chechitatu ndiko kudyidzana nesamende.
Kuchengetedzwa kwemvura kweselulosi ether kunoenderana nekutorwa kwemvura kwegadziko layer, kuumbwa kwedhaka, ukobvu hwedhaka redhaka, kudiwa kwemvura kwedhaka, uye nguva yekumisikidzwa kwechinhu chekugadzika.Kuchengetwa kwemvura kwe cellulose ether pachayo kunobva mukunyungudika uye kupera simba kweselulosi ether pachayo.Sezvo isu tose tinoziva, kunyange zvazvo cellulose molecular chain ine nhamba yakawanda yeakanyanya hydratable OH mapoka, haisi kunyunguduka mumvura, nokuti chimiro che cellulose chine hukuru hwekristallinity.Kugona kwe hydration kwemapoka ehydroxyl chete hakuna kukwana kuvhara mabhondi akasimba ehydrogen uye van der Waals masimba pakati pemamorekuru.Naizvozvo, inongozvimba asi hainyungudika mumvura.Kana chinotsiva chinopinzwa mucheni yemamorekuru, kwete chete chinotsiva chinoparadza cheni yehydrogen, asiwo iyo interchain hydrogen bond inoparadzwa nekuda kwekuroora kweiyo inotsiva pakati pemaketani ari padyo.Iyo yakakura inotsiva, yakakura chinhambwe pakati pemamorekuru.Iyo yakakura chinhambwe.Iyo yakakura mhedzisiro yekuparadza hydrogen zvisungo, iyo cellulose ether inonyungudika mumvura mushure mekunge cellulose lattice ichiwedzera uye mhinduro inopinda, ichigadzira yakakwirira-viscosity mhinduro.Kana kutonhora kuchikwira, hydration yepolymer inopera, uye mvura pakati pemaketani inodzingwa kunze.Kana iyo dehydration effect yakakwana, mamorekuru anotanga kuungana, achigadzira matatu-dimensional network dhizaini gel uye akapetwa kunze.Zvinhu zvinokanganisa kuchengetwa kwemvura yedhaka zvinosanganisira viscosity ye cellulose ether, huwandu hwakawedzerwa, kunaka kwezvimedu uye tembiricha yekushandisa.
Iyo yakakwirira viscosity ye cellulose ether, zviri nani kuchengetedza mvura kuita, uye yakakwirira viscosity yemushonga wepolymer.Zvichienderana nehuremu hwemamorekuru (polymerization dhigirii) yepolymer, inotemerwawo nehurefu hwemaketani echimiro chemamorekuru uye chimiro checheni, uye kugoverwa kwemhando uye huwandu hwezvinotsiva zvinokanganisawo zvakananga chiyero chayo che viscosity.[η]=Kmα
[η] Intrinsic viscosity yepolymer solution
m polymer molecular uremu
α polymer maitiro anogara aripo
K viscosity solution coefficient
Iyo viscosity yemushonga wepolymer zvinoenderana nehuremu hwema molecular epolymer.Iyo viscosity uye kusangana kwe cellulose ether mhinduro ine hukama nekushandiswa munzvimbo dzakasiyana siyana.Nokudaro, imwe neimwe cellulose ether ine zvakawanda zvakasiyana-siyana zveviscosity tsanangudzo, uye kugadzirisa kwe viscosity kunonyanya kuonekwa nekuora kwe alkali cellulose, kureva, kuputika kwe cellulose molecular cheni.
Iyo yakawanda yakawanda ye cellulose ether yakawedzerwa kune dhaka, zviri nani kuchengetedza kwemvura kushanda, uye yakakwirira viscosity, zviri nani kuchengetedza mvura kushanda.
Pakukura kwechidimbu, iyo yakatsetseka chidimbu, zviri nani kuchengetedza mvura.Ona Mufananidzo 3. Mushure mokunge chikamu chikuru che cellulose ether chasangana nemvura, nzvimbo yacho inonyunguduka pakarepo uye inoumba gel rekuputira zvinhu kudzivirira mamorekuru emvura kuti arambe achipinda.Zvisingasviki kupararira kweyunifomu kunonyunguduka, kuumba cloudy flocculent solution kana agglomerates.Inobata zvakanyanya kuchengetwa kwemvura ye cellulose ether, uye solubility chimwe chezvinhu zvekusarudza cellulose ether.
Thickening uye Thixotropy yeCellulose Ether
Basa rechipiri re cellulose ether - thickening, zvinoenderana ne: dhigirii yepolymerization ye cellulose ether, kugadziriswa kwekugadzirisa, shear rate, tembiricha uye mamwe mamiriro.Iyo gelling midziyo yemushonga yakasarudzika kune alkyl cellulose uye yakagadziridzwa maderivatives.Iyo gelation zvivakwa zvine hukama neiyo dhigirii yekutsiva, kugadzirisa kugadzirisa uye zvinowedzera.Kune hydroxyalkyl yakagadziridzwa derivatives, iyo gel zvivakwa zvine hukamawo nedhigirii rekuchinja rehydroxyalkyl.Kune yakaderera viscosity MC uye HPMC, 10% -15% mhinduro inogona kugadzirirwa, yepakati viscosity MC uye HPMC inogona kugadzirirwa 5% -10% mhinduro, uye yakakwirira viscosity MC uye HPMC inogona chete kugadzirira 2% -3% mhinduro, uye kazhinji. Iyo viscosity classification ye cellulose ether inoiswawo grade 1% -2% mhinduro.High molecular weight cellulose ether ine high thickening kunyatsoita.Mune imwecheteyo yekugadzirisa mhinduro, mapolymer ane akasiyana ma molecular uremu ane akasiyana viscosities.High degree.Iyo inonangwa viscosity inogona kuwanikwa chete nekuwedzera yakawanda yakaderera molecular uremu cellulose ether.Viscosity yaro haina kutsamira pachiyero chekuveura, uye iyo yakakwira viscosity inosvika painotariswa viscosity, uye iyo inodiwa yekuwedzera mari idiki, uye viscosity zvinoenderana nekukora kwekuita.Naizvozvo, kuti uwane kumwe kuenderana, imwe chiyero che cellulose ether (concentration yemhinduro) uye mhinduro viscosity inofanira kuvimbiswa.Iyo tembiricha yegel yemushonga zvakare inodzikira mutsetse nekuwedzera kwekusangana kwemhinduro, uye gels pane tembiricha yekamuri mushure mekusvika kumwe kusungwa.Iyo gelling concentration yeHPMC yakakwira zvakanyanya pakamuri tembiricha.
Consistency inogonawo kugadziriswa nekusarudza particle size uye kusarudza cellulose ethers ane madhigirii akasiyana ekugadzirisa.Iyo inonzi shanduko ndeye kuunza imwe dhigirii yekutsiva yemapoka ehydroxyalkyl pane skeleton chimiro cheMC.Nekushandura hukama hwekutsinhanisa hunhu hwezviviri zvinotsiva, kureva, iyo DS neMS inotsinhanisa tsika dzemapoka emethoxy nehydroxyalkyl atinowanzo kutaura.Zvido zvakasiyana-siyana zvekushanda zve cellulose ether zvinogona kuwanikwa kuburikidza nekushandura hukama hunotsiviwa hwezviviri zvinotsiva.
Cellulose ethers inoshandiswa muupfu zvivakwa zvekuvaka inofanirwa kunyungudika nekukurumidza mumvura inotonhora uye inopa kuenderana kwakakodzera kwehurongwa.Kana yakapihwa imwe shear rate, inoramba ichivhurika uye colloidal block, iri pasi pemhando kana yakashata mhando chigadzirwa.
Kune zvakare hukama hwakanaka hwemutsara pakati pekuenderana kwesamende paste uye dosi ye cellulose ether.Cellulose ether inogona kuwedzera zvakanyanya viscosity yedhaka.Iyo yakakura dosage, zvinonyanya kuoneka mugumisiro.
High-viscosity cellulose ether aqueous solution ine high thixotropy, iyo iriwo hunhu hukuru hwe cellulose ether.Aqueous solutions yeMC polymers kazhinji ane pseudoplastic uye isiri-thixotropic fluidity pazasi petembiricha yavo yegel, asi Newtonian inoyerera zvivakwa pazasi shear mitengo.Pseudoplasticity inowedzera nehuremu hwemamorekuru kana kuungana kweselulosi ether, zvisinei nerudzi rwechinotsiva uye dhigirii rekutsiva.Nokudaro, cellulose ethers yegiredhi rimwechete viscosity, zvisinei MC, HPMC, HEMC, inogara ichiratidza zvakafanana rheological properties chero bedzi kusungirirwa uye kutonhora kuchichengetwa nguva dzose.Magero ekugadzira anoumbwa kana tembiricha yakasimudzwa, uye yakanyanya thixotropic inoyerera inoitika.High concentration uye low viscosity cellulose ethers inoratidza thixotropy kunyange pasi pekushisa kwegel.Ichi chivakwa chinobatsira zvikuru kugadziridzwa kwemazinga uye kusagika mukuvaka dhaka rekuvaka.Zvinoda kutsanangurwa pano kuti kukwirisa viscosity ye cellulose ether, zviri nani kuchengetwa kwemvura, asi iyo yakakwira viscosity, iyo inokwira yakaenzana molecular uremu hwe cellulose ether, uye kuderera kunoenderana mukunyungudika kwayo, uko kune kukanganisa kwakashata. pamusoro pekugadzirisa kwedhaka uye kushanda kwekuvaka.Iyo yakakwirira viscosity, iyo inonyanya kuoneka iyo thickening maitiro padhaka, asi haina kuenzana zvachose.Imwe yepakati uye yakaderera viscosity, asi iyo yakagadziridzwa cellulose ether ine kuita kuri nani mukuvandudza kusimba kwechimiro chedhaka rakanyorova.Nekuwedzera kwe viscosity, kuchengetwa kwemvura kwe cellulose ether kunovandudza
Nguva yekutumira: Nov-22-2022