Methylcellulose (MC) imhando ye cellulose ether. Cellulose ether compounds imhando ye cellulose inogadzirwa ne chemical modification ye natural cellulose, uye methylcellulose i cellulose derivative yakakosha inoumbwa ne methylating (methyl substitution) chikamu che hydroxyl che cellulose. Saka, methylcellulose haisi cellulose derivative chete, asiwo cellulose ether yakajairika.
1. Kugadzirira methylcellulose
Methylcellulose inogadzirwa nekuita reactive cellulose nemushonga wemethylating (wakaita semethyl chloride kana dimethyl sulfate) pasi pemamiriro ealkaline kuti iite methylate chikamu chehydroxyl checellulose. Kuita uku kunonyanya kuitika pamapoka ehydroxyl panzvimbo dzeC2, C3 neC6 dzecellulose kuti igadzire methylcellulose ine madhigirii akasiyana ekutsiva. Maitiro ekuita izvi ndeekuti:
Cellulose (polysaccharide inoumbwa nemayuniti eglucose) inotanga yashanda mumamiriro ezvinhu ealkaline;
Zvadaro mushonga we methylating unounzwa kuti uite etherification reaction kuti uwane methylcellulose.
Nzira iyi inogona kugadzira zvigadzirwa zve methylcellulose zvine viscosities dzakasiyana uye solubility properties nekutonga mamiriro e reaction uye mwero we methylation.
2. Hunhu hwemethylcellulose
Methylcellulose ine zvinhu zvikuru zvinotevera:
Kunyungudika: Kusiyana ne cellulose yechisikigo, methylcellulose inogona kunyungudika mumvura inotonhora asi kwete mumvura inopisa. Izvi zvinodaro nekuti kuiswa kwe methyl substituents kunoparadza hydrogen bonds pakati pemamorekuru e cellulose, nokudaro zvichideredza crystallinity yayo. Methylcellulose inoumba mhinduro yakajeka mumvura uye inoratidza hunhu hwe gelation pakupisa kwakanyanya, kureva kuti, mhinduro yacho inokora kana yapiswa uye inodzoka pakunyorova mushure mekutonhora.
Haisi chepfu: Methylcellulose haina chepfu uye hainyudzwe nekugaya kwevanhu. Nokudaro, inowanzoshandiswa muzvikafu uye mumishonga sechinosimbisa, chinosimbisa uye chinosimbisa.
Kudzora kusimba kwemuviri: Methylcellulose ine hunhu hwakanaka hwekudzora kusimba kwemuviri, uye kusimba kwemuviri wayo kunoenderana nekuwanda kwemushonga uye huremu hwemamorekuru. Nekudzora mwero wekutsiva mu etherification reaction, zvigadzirwa zve methylcellulose zvine huwandu hwakasiyana hwekusimba kwemuviri zvinogona kuwanikwa.
3. Mashandisirwo emethylcellulose
Nekuda kwehunhu hwayo hwepanyama nemakemikari, methylcellulose yave ichishandiswa zvakanyanya mumaindasitiri mazhinji.
3.1 Indasitiri yezvekudya
Methylcellulose chinhu chinowanzo shandiswa mukugadzira chikafu zvakasiyana-siyana, kunyanya sechinosimbisa, chinosanganisa makemikari uye chinosimbisa. Sezvo methylcellulose ichigona kunyorova kana yadziiswa uye ichidzoreredza kuyerera kwemvura mushure mekutonhora, inowanzoshandiswa muzvikafu zvakachengetwa mufiriji, zvakabikwa uye mumasobho. Pamusoro pezvo, hunhu hwemethylcellulose husina macalorie akawanda hunoita kuti ive chinhu chakakosha mune mamwe maforomamu echikafu ane macalorie mashoma.
3.2 Maindasitiri emishonga nekurapa
Methylcellulose inoshandiswa zvakanyanya muindasitiri yemishonga, kunyanya mukugadzirwa kwemapiritsi, sechinhu chinobatsira uye chinosunga. Nekuda kwekugona kwayo kugadzirisa viscosity, inogona kuvandudza simba remuchina uye hunhu hwekuputsika kwemapiritsi. Pamusoro pezvo, methylcellulose inoshandiswawo sechinhu chekugadzira kubvaruka mumaziso kurapa maziso akaoma.
3.3 Indasitiri yekuvaka nezvinhu zvekushandisa
Pakati pezvinhu zvekuvaka, methylcellulose inoshandiswa zvakanyanya mu simende, gypsum, machira uye zvinonamatira sechinosimbisa, chinochengetedza mvura uye chinoumba firimu. Nekuda kwekuchengetedza kwayo mvura zvakanaka, methylcellulose inogona kuvandudza kuyerera uye kushanda kwezvinhu zvekuvaka uye kudzivirira kutsemuka nemaburi.
3.4 Indasitiri yezvekunaka
Methylcellulose inowanzoshandiswawo muindasitiri yezvizoro sechinosimbisa uye chinosimbisa ganda kuti rigadzire ma emulsion nema gels anogara kwenguva refu. Inogona kunatsiridza kunzwa kwechigadzirwa uye kuwedzera hunyoro. Haina allergies uye haina kunyorova, uye yakakodzera ganda rinonzwa kurwadza.
4. Kuenzanisa kwemethylcellulose nedzimwe ether dze cellulose
Cellulose ethers imhuri yakakura. Pamusoro pemethylcellulose, kunewo ethyl cellulose (EC), hydroxypropyl methylcellulose (HPMC), hydroxyethyl cellulose (HEC) nedzimwe mhando. Musiyano wavo mukuru uri murudzi uye mwero wekutsiva zvinhu zvinotsiva pane cellulose molecule, izvo zvinosarudza kunyunguduka kwadzo, viscosity uye nzvimbo dzekushandiswa.
Methylcellulose vs Hydroxypropyl Methylcellulose (HPMC): HPMC imhando yakagadziridzwa yemethylcellulose. Pamusoro pemethyl substituent, hydroxypropyl inounzwawo, izvo zvinoita kuti HPMC inyunguduke zvakasiyana-siyana. HPMC inogona kunyungudutswa mumhando yekupisa yakakura, uye tembiricha yayo yekupisa yakakwira kupfuura yemethylcellulose. Saka, muzvivakwa zvekuvaka uye maindasitiri emishonga, HPMC ine mhando dzakasiyana dzemashandisirwo.
Methylcellulose vs Ethyl Cellulose (EC): Ethyl cellulose hainyungudike mumvura, asi inonyungudika muzvinhu zvinonyungudika zve organic. Inowanzo shandiswa muzvinhu zvinoburitswa ne membrane zvinogara kwenguva refu zvekuputira nemishonga. Methyl cellulose inonyungudika mumvura inotonhora uye inonyanya kushandiswa sechinhu chinosimbisa uye chinochengetedza mvura. Nzvimbo dzayo dzekushandisa dzakasiyana nedze ethyl cellulose.
5. Kufambira mberi kwekukura kwe cellulose ethers
Nekuwedzera kuri kuita kudiwa kwezvinhu zvinogara kwenguva refu uye makemikari akasvibira, makemikari e-cellulose ether, kusanganisira methyl cellulose, ari kuva chikamu chakakosha chezvinhu zvisingakuvadzi nharaunda. Anobva mumiti yechisikigo, anogona kudzokororwa, uye anogona kuora zvakasikwa munzvimbo yakapoteredza. Mune ramangwana, nzvimbo dzinoshandiswa dze-cellulose ethers dzinogona kuwedzerwa, senge musimba idzva, zvivakwa zvakasvibira uye biomedicine.
Semhando ye cellulose ether, methyl cellulose inoshandiswa zvakanyanya mumaindasitiri mazhinji nekuda kwehunhu hwayo hwepanyama nemakemikari. Haingogumiri pakunyunguduka kwakanaka, kusakuvadza chepfu, uye kugona kugadzirisa viscosity zvakanaka, asiwo ine basa rakakosha mukudya, mishonga, kuvaka uye zvizoro. Mune ramangwana, nekudiwa kuri kuwedzera kwezvinhu zvisina njodzi kunharaunda, mikana yekushandiswa kwemethyl cellulose ichave yakakura.
Nguva yekutumira: Gumiguru-23-2024