Methylcellulose (MC)
Fomura yemamorekuru yemethylcellulose (MC) ndeiyi:
[C6H7O2(OH)3-h(OCH3)n\]x
Maitiro ekugadzira ndeyekugadzira cellulose ether kuburikidza nematanho akasiyana-siyana mushure mekunge donje rakanatswa ragadziriswa nealkali, uye methyl chloride inoshandiswa se etherification agent. Kazhinji, mwero wekutsiva i1.6 ~ 2.0, uye kunyunguduka kwakasiyanawo nemazinga akasiyana ekutsiva. Ndeye non-ionic cellulose ether.
Methylcellulose inonyungudika mumvura inotonhora, uye zvichave zvakaoma kunyungudika mumvura inopisa. Mvura yayo inonyungudika zvikuru kana iri pakati pe pH = 3 ~ 12.
Inoshanda zvakanaka nestarch, guar gum, nezvimwewo uye ma surfactants akawanda. Kana tembiricha yasvika patembiricha ye gelation, gelation inoitika.
Kuchengetwa kwemvura kwemethylcellulose kunoenderana nehuwandu hwayo, viscosity, kupfava kwezvikamu uye mwero wekunyungudika kwayo.
Kazhinji, kana huwandu hwekuwedzera huri hukuru, hutete hushoma, uye hutete hwakawanda, mwero wekuchengetedza mvura wakakwira. Pakati pazvo, huwandu hwekuwedzera hune simba guru pahuwandu hwekuchengetedza mvura, uye mwero wehutete hauenderane zvakananga nehuwandu hwehuwandu hwekuchengetedza mvura. Mwero wekuparadzwa unonyanya kuenderana nehuwandu hwekuchinja kwepamusoro pezvikamu zve cellulose uye hutete hwezvikamu.
Pakati pema cellulose ethers ari pamusoro apa, methyl cellulose nehydroxypropyl methyl cellulose zvine mwero wepamusoro wekuchengetedza mvura.
Carboxymethylcellulose (CMC)
Carboxymethyl cellulose, inozivikanwawo sesodium carboxymethyl cellulose, inowanzozivikanwa secellulose, cmc, nezvimwewo, ipolymer ine anionic linear, munyu wesodium we cellulose carboxylate, uye inogona kushandiswazve uye haiperi. Zvinhu zvemakemikari.
Inonyanya kushandiswa muindasitiri yekuchenesa, indasitiri yezvekudya uye mvura inocherwa muminda yemafuta, uye huwandu hunoshandiswa muzvizoro hunosvika 1% chete.
Ionic cellulose ether inogadzirwa kubva mufibers dzechisikigo (donje, nezvimwewo) mushure mekurapwa nealkali, ichishandisa sodium monochloroacetate se etherification agent, uye ichirapwa kakawanda.
Dhigirii rekutsiva rinowanzova 0.4 ~ 1.4, uye mashandiro aro anokanganiswa zvakanyanya nedhigirii rekutsiva.
CMC ine kugona kwakanaka kwekusunga, uye mhinduro yayo yemvura ine kugona kwakanaka kwekumisa, asi hapana kukosha kwechokwadi kwekuchinja kwepurasitiki.
Kana CMC yanyungudika, depolymerization inoitika zvechokwadi. Viscosity inotanga kukwira panguva yekunyungudika, inopfuura nepakati pepamusoro, yozodonha kusvika pakakwirira. Viscosity inobuda inoenderana ne depolymerization.
Kuwanda kwe depolymerization kwakabatana zvakanyanya nehuwandu hwe solvent isina kunaka (mvura) muchimiro. Mu system isina kunaka yekusolvent, senge toothpaste ine glycerin nemvura, CMC haizombobvisi polymer zvachose uye ichasvika padanho rekuenzanisa.
Kana paine huwandu hwakati hwemvura, CMC inotsiva mvura yakawanda inonyungudika zvikuru iri nyore kubvisa polymer pane CMC inotsiva yakaderera.
Hydroxyethylcellulose (HEC)
HEC inogadzirwa nekushandisa donje rakanatswa nealkali, uye yozosanganiswa ne ethylene oxide se etherification agent kana paine acetone. Mwero wekutsiva unowanzova 1.5 ~ 2.0. Ine hydrophilicity yakasimba uye iri nyore kunwisa hunyoro.
Hydroxyethyl cellulose inonyungudika mumvura inotonhora, asi inonetsa kunyungudika mumvura inopisa. Mhinduro yayo inogara yakasimba kana tembiricha yakakwira isina gelling.
Yakasimba kune maasidhi nemabhesi akajairika. Alkalis inogona kukurumidzisa kunyungudika kwayo uye kuwedzera viscosity yayo zvishoma. Kupararira kwayo mumvura kwakaipa zvishoma pane kwemethyl cellulose uye hydroxypropyl methyl cellulose.
Hydroxypropyl Methyl Cellulose (HPMC)
Fomura yemamorekuru yeHPMC ndeiyi:
\[C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3\]n\]x
Hydroxypropyl methylcellulose rudzi rwe cellulose iyo kubuda kwayo uye kushandiswa kwayo kuri kuwedzera nekukurumidza.
Imhando ye ether isina ionic cellulose yakagadzirwa nedonje rakacheneswa mushure mekugadziriswa kwe alkali, ichishandisa propylene oxide ne methyl chloride se etherification agent, kuburikidza nekuita kwakasiyana-siyana. Dhigirii rekutsiva rinowanzova 1.2 ~ 2.0.
Hunhu hwayo hwakasiyana nekuda kwehuwandu hwakasiyana hwemethoxyl nehuwandu hwehydroxypropyl.
Hydroxypropyl methylcellulose inonyungudika nyore nyore mumvura inotonhora, asi ichaomerwa nekunyungudika mumvura inopisa. Asi tembiricha yayo ye gelation mumvura inopisa yakakwira zvakanyanya kupfuura yemethyl cellulose. Kunyungudika mumvura inotonhora kwakawedzerawo zvikuru kana tichienzanisa nemethyl cellulose.
Kuwanda kwehydroxypropyl methylcellulose kwakabatana nehuremu hwayo hwemamorekuru, uye kana huremu hwemamorekuru hwakakura, kuwanda kwesimba. Tembiricha inokanganisawo kuwanda kwayo, sezvo tembiricha ichiwedzera, kuderera kwesimba. Zvisinei, kuwanda kwayo kune tembiricha yakaderera pane methyl cellulose. Mhinduro yayo inogara yakagadzikana kana yakachengetwa patembiricha yemumba.
Kuchengetwa kwemvura kwehydroxypropyl methylcellulose kunoenderana nehuwandu hwayo hwekuwedzera, viscosity, nezvimwewo, uye mwero wayo wekuchengetedza mvura nehuwandu hwayo hwekuwedzera hwakakwira kupfuura hwemethyl cellulose.
Hydroxypropyl methylcellulose inogara yakasimba kune acid nealkali, uye mvura yayo inogadzikana zvakanyanya muhuwandu hwe pH = 2 ~ 12. Caustic soda nemvura ye lime hazvina zvazvinobatsira pakushanda kwayo, asi alkali inogona kukurumidzisa kunyungudika kwayo uye kuwedzera viscosity yayo.
Hydroxypropyl methylcellulose inogara yakagadzikana kune munyu wakajairika, asi kana huwandu hwemunyu hwakanyanya, viscosity ye hydroxypropyl methylcellulose solution inowanzo kuwedzera.
Hydroxypropyl methylcellulose inogona kusanganiswa nepolymer inonyungudika mumvura kuti igadzire mhinduro yakafanana uye yakakwira ye viscosity. Zvakadai se polyvinyl alcohol, starch ether, vegetable gum, nezvimwewo.
Hydroxypropyl methylcellulose ine simba rekudzivirira ma enzymes zviri nani kupfuura methylcellulose, uye mhinduro yayo haina mukana wekuora enzymes kupfuura methylcellulose.
Nguva yekutumira: Kukadzi-14-2023