Cellulose ether ni polymer yubukorikori ikozwe muri selile naturel binyuze muburyo bwo guhindura imiti.Cellulose ether ni inkomoko ya selile naturel.Umusaruro wa selulose ether uratandukanye na polymrike ya synthique.Ibikoresho byibanze byingenzi ni selile, ibinyabuzima bisanzwe bya polymer.Bitewe numwihariko wimiterere ya selile isanzwe, selile ubwayo ntabwo ifite ubushobozi bwo kubyitwaramo na etherification.Ariko, nyuma yo kuvura imiti yabyimbye, imiyoboro ikomeye ya hydrogène iri hagati yiminyururu ya molekile n'iminyururu irasenyuka, kandi kurekura gukomeye kwitsinda hydroxyl bihinduka selile ya alkali selile.Shakisha selile.
Ibiranga selile ya selile biterwa n'ubwoko, umubare no gukwirakwiza insimburangingo.Itondekanya rya selile ya selile nayo ishingiye ku bwoko bwinsimburangingo, urwego rwa etherification, solubile hamwe nibisabwa bijyanye.Ukurikije ubwoko bwinsimburangingo kumurongo wa molekile, irashobora kugabanywamo monoether hamwe na ether ivanze.Mubisanzwe dukoresha mc nka monoether, na HPmc nka ether ivanze.Methyl selulose ether mc nigicuruzwa nyuma yitsinda rya hydroxyl kumurongo wa glucose ya selile ya selile isanzwe isimburwa nitsinda ryimikorere.Nibicuruzwa byabonetse mugusimbuza igice cyitsinda rya hydroxyl kumurongo hamwe nitsinda ryimikorere naho ikindi gice hamwe nitsinda rya hydroxypropyl.Imiterere yuburyo ni [C6H7O2 (OH) 3-mn (OCH3) m [OCH2CH (OH) CH3] n] x Hydroxyethyl methyl selulose ether HEmc, ubu ni ubwoko bwingenzi bukoreshwa cyane kandi bugurishwa ku isoko.
Kubijyanye no kwikemurira ibibazo, birashobora kugabanywamo ionic na non-ionic.Amazi ashonga adafite ionic selulose ethers agizwe ahanini nuruhererekane rwibintu bibiri bya alkyl ethers na hydroxyalkyl ethers.Ionic Cmc ikoreshwa cyane mubikoresho byogeza, gucapa imyenda no gusiga irangi, ibiryo nubushakashatsi bwamavuta.Non-ionic mc, HPmc, HEmc, nibindi bikoreshwa cyane mubikoresho byubwubatsi, gutwikira latx, imiti, imiti ya buri munsi, nibindi bikoreshwa nkibibyimbye, bigumana amazi, stabilisateur, ikwirakwiza hamwe nogukora firime.
Kubika amazi ya selile ether
Mu gukora ibikoresho byubwubatsi, cyane cyane byumye-bivanze na minisiteri, selile ether ifite uruhare rudasimburwa, cyane cyane mugukora minisiteri idasanzwe (minisiteri yahinduwe), nikintu cyingenzi kandi cyingenzi.
Uruhare rwingenzi rwa selulose ether-ether-ether-ether muri minisiteri ahanini ifite ibintu bitatu, kimwe nubushobozi buhebuje bwo gufata amazi, ikindi ni ingaruka ku guhuza hamwe na thixotropy ya minisiteri, naho icya gatatu ni imikoranire na sima.
Ingaruka yo gufata amazi ya selile ya selile biterwa no kwinjiza amazi kurwego rwibanze, imiterere ya minisiteri, ubunini bwikigero cya minisiteri, amazi akenerwa na minisiteri, nigihe cyo kugenera ibikoresho.Kugumana amazi ya selile ether ubwayo bituruka kumashanyarazi no kubura umwuma wa selile ubwayo.Nkuko twese tubizi, nubwo urunigi rwa selile ya selile irimo umubare munini wamatsinda ya OH afite ingufu nyinshi, ntabwo ashonga mumazi, kuko imiterere ya selile ifite urwego rwo hejuru rwa kristu.Ubushobozi bwo kuyobora amatsinda ya hydroxyl yonyine ntibihagije kugirango uhuze imigozi ikomeye ya hydrogène nimbaraga za van der Waals hagati ya molekile.Kubwibyo, irabyimba gusa ariko ntishonga mumazi.Iyo insimburangingo yinjijwe mumurongo wa molekile, ntabwo insimburangingo yangiza urunigi rwa hydrogène gusa, ariko kandi isano ya hydrogène ihuza imiyoboro irasenywa bitewe no guhuza insimburangingo hagati yiminyururu yegeranye.Ninini isimbuye, niko intera iri hagati ya molekile.Intera nini.Ingaruka nini zo gusenya imigozi ya hydrogène, ether ya selulose ihinduka amazi-nyuma ya latulice ya selile yagutse kandi igisubizo kikinjira, kigakora igisubizo cyinshi cyane.Iyo ubushyuhe buzamutse, hydrated ya polymer igabanuka, kandi amazi ari hagati yiminyururu yirukanwa.Iyo ingaruka zo kubura umwuma zihagije, molekile zitangira kwegeranya, zikora imiterere-yimiterere-yimiterere-itatu igizwe na gel hanyuma ikazunguruka.Ibintu bigira ingaruka ku gufata amazi ya minisiteri harimo ubwiza bwa selile ya selile, umubare wongeyeho, ubwiza bwibice hamwe nubushyuhe bwo gukoresha.
Iyo hejuru ya viscosity ya selulose ether, niko imikorere myiza yo gufata amazi, hamwe nubusembwa bwumuti wa polymer.Ukurikije uburemere bwa molekuline (polymerisiyasi) ya polymer, bigenwa kandi nuburebure bwurunigi rwimiterere ya molekile n'imiterere y'urunigi, kandi ikwirakwizwa ryubwoko nubwinshi bwibisimbura nabyo bigira ingaruka muburyo butagaragara.[η] = Kmα
[η] Ubwiza bwimbere bwumuti wa polymer
m uburemere bwa polymer
α polymer iranga guhoraho
K coefficient de coiffe
Ubukonje bwumuti wa polymer biterwa nuburemere bwa molekuline ya polymer.Ubukonje hamwe nubushakashatsi bwa selulose ether igisubizo kijyanye no gusaba mubice bitandukanye.Kubwibyo, buri selire ya ether ifite ibintu byinshi bitandukanye byijimye, kandi ihinduka ryubwiza bigaragarira cyane cyane no kwangirika kwa alkali selile, ni ukuvuga kumena ingoyi ya selile.
Umubare munini wa selulose ether wongeyeho kuri minisiteri, niko imikorere myiza yo gufata amazi, hamwe nubukonje bwinshi, nuburyo bwiza bwo gufata amazi.
Ku bunini bw'ingirangingo, ni byiza cyane, gufata neza amazi (reba Ishusho 3).Nyuma yuko ibice binini bya selile ya selile ihuye namazi, ubuso burahita bushonga hanyuma bugakora jel yo gupfunyika ibikoresho kugirango birinde molekile zamazi gukomeza kwinjira.Rimwe na rimwe, ntishobora gutandukana kimwe no gushonga nubwo nyuma yigihe kirekire ikurura, igakora igisubizo cyijimye cyangwa igiterane.Ifite cyane cyane kubika amazi ya selile ya selile, kandi gukomera ni kimwe mubintu byo guhitamo selile.
Umubyimba na Thixotropy ya Cellulose Ether
Igikorwa cya kabiri cya selulose ether - kubyimba biterwa na: urwego rwa polymerisation ya selile ya ether, kwibanda kumuti, igipimo cyogosha, ubushyuhe nibindi bihe.Umutungo wa gelling wigisubizo wihariye kuri alkyl selulose nibiyikomokaho.Imiterere ya gelation ifitanye isano nurwego rwo gusimbuza, kwibanda kubisubizo hamwe ninyongera.Kuri hydroxyalkyl yahinduwe ikomokaho, imiterere ya gel nayo ifitanye isano nimpinduka ya hydroxyalkyl.Kuri mc na HPmc hamwe nubukonje buke, 10% -15% yumuti wibisubizo birashobora gutegurwa, 5% -10% igisubizo kirashobora gutegurwa kubiciriritse biciriritse mc na HPmc, naho 2% -3% birashobora gutegurwa kubwinshi bwa mc kandi HPmc, kandi mubisanzwe Ubwiza bwurwego rwa selulose ether nayo yashyizwe hamwe na 1% -2% yumuti.Uburemere buke bwa selile selile ether ifite ubushobozi bwo kubyimba cyane.Mubisubizo bimwe byo kwibandaho, polymers ifite uburemere butandukanye bwa molekile ifite viscosities zitandukanye.Urwego rwo hejuru.Intego yo kwiyegereza irashobora kugerwaho gusa wongeyeho umubare munini wuburemere buke bwa selile selile.Ubukonje bwabwo ntaho butaniye nigipimo cyogosha, kandi ubukonje bwinshi bugera ku ntego yo kwiyegereza, kandi amafaranga asabwa yongeweho ni make, kandi ubwiza buterwa no kubyimba neza.Kubwibyo, kugirango ugere kumurongo runaka, umubare munini wa selile ya selile (kwibanda kumuti) hamwe nubwiza bwibisubizo bigomba kwemezwa.Ubushyuhe bwa gel bwumuti nabwo bugabanuka kumurongo hamwe no kwiyongera kwumuti wibisubizo, hamwe na geles mubushyuhe bwicyumba nyuma yo kugera kumurongo runaka.Ubushuhe bwa HPmc buri hejuru mubushyuhe bwicyumba.
Guhuzagurika birashobora kandi guhinduka muguhitamo ingano yingingo no guhitamo selile ya selile hamwe nimpamyabumenyi zitandukanye.Ibyo bita guhindura ni ukumenyekanisha urwego runaka rwo gusimbuza hydroxyalkyl matsinda kumiterere ya skeleton ya mc.Muguhindura indangagaciro yo gusimbuza indangagaciro zibiri zasimbuwe, ni ukuvuga, DS na ms ugereranije no gusimbuza indangagaciro za methoxy na hydroxyalkyl amatsinda dukunze kuvuga.Ibikorwa bitandukanye bisabwa bya selile ether birashobora kuboneka muguhindura agaciro kagereranijwe gusimbuza ibintu byombi.
Ether ya selile ikoreshwa mubikoresho byubwubatsi bigomba gushonga vuba mumazi akonje kandi bigatanga uburyo bukwiye kuri sisitemu.Niba uhaye igipimo runaka cyogosha, iracyahinduka flocculent na colloidal block, nigicuruzwa kitujuje ubuziranenge cyangwa cyiza.
Hariho kandi umurongo mwiza uhuza umurongo hagati ya sima paste na dosiye ya selile ether.Cellulose ether irashobora kongera cyane ubwiza bwa minisiteri.Nini nini, niko bigaragara ingaruka, reba Ishusho ya 6
Umuvuduko mwinshi wa selileose ether amazi yo mumazi afite thixotropy nyinshi, nayo nikintu gikomeye kiranga selile ether.Ibisubizo byamazi ya polimeri yo mu bwoko bwa Mc mubusanzwe bifite pseudoplastique na non-thixotropic fluid munsi yubushyuhe bwa gel, ariko ibintu bitemba bya Newtonian ku gipimo gito.Pseudoplastique yiyongera hamwe nuburemere bwa molekuline cyangwa kwibumbira hamwe kwa selile ya ether, hatitawe ku bwoko bwinsimburangingo no kurwego rwo gusimburwa.Kubwibyo, selulose ethers yo murwego rumwe rwa viscosity, ntakibazo mc, HPmc, HEmc, izahora yerekana imiterere imwe ya rheologiya mugihe cyose ubushyuhe nubushyuhe bikomeza guhoraho.Gele yubaka ikorwa mugihe ubushyuhe buzamutse, kandi tixotropique itemba cyane.Ubushuhe bwinshi hamwe na selile nkeya ya selile yerekana thixotropy ndetse no munsi yubushyuhe bwa gel.Uyu mutungo ufite akamaro kanini muguhindura kuringaniza no kugabanuka mukubaka inyubako ya minisiteri.Hagomba gusobanurwa hano ko uko ubukonje bwa ether ya selulose, niko gufata amazi neza, ariko uko ubukonje bugenda bwiyongera, niko uburemere bwa molekuline bugereranije na selile ya selile, hamwe no kugabanuka gukwiranye kwayo, bigira ingaruka mbi kuri concentration ya minisiteri nibikorwa byubwubatsi.Iyo hejuru ya viscosity, niko bigaragara ingaruka zo kubyimba kuri minisiteri, ariko ntabwo ihwanye rwose.Bimwe mubiciriritse kandi bito, ariko selile yahinduwe ya selile ifite imikorere myiza mugutezimbere imbaraga zimiterere ya minisiteri itose.Hamwe no kwiyongera kwijimye, kugumana amazi ya selile ether biratera imbere.
Igihe cyo kohereza: Ugushyingo-22-2022