Methylcellulose (MC)
Iyo molecular formula ye methylcellulose (MC) ndeye:
[C6H7O2(OH)3-h(OCH3)n\]x
Maitiro ekugadzira ndeekugadzira cellulose ether kuburikidza neakatevedzana maitiro mushure mekunge donje rakanatswa rabatwa nealkali, uye methyl chloride inoshandiswa seetherification agent. Kazhinji, dhigirii rekutsiva i1.6 ~ 2.0, uye kunyungudika kwakasiyanawo nemadhigirii akasiyana ekutsiva. Iyo ndeye isiri-ionic cellulose ether.
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.
Kuchengetwa kwemvura kwemethylcellulose 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.
Carboxymethylcellulose (CMC)
Carboxymethyl cellulose, inozivikanwawo se sodium carboxymethyl cellulose, inowanzo zivikanwa se cellulose, cmc, nezvimwewo, is an anionic linear polymer, sodium munyu we cellulose carboxylate, uye inogona kuvandudzwa uye isingapere. Kemikari raw materials.
Inonyanya kushandiswa muindasitiri yekuchenesa, indasitiri yechikafu uye mafuta ekuchera mvura yemumunda, uye huwandu hunoshandiswa muzvizora hunoita 1%.
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.
CMC ine yakanakisa kusunga kugona, uye mhinduro yayo yemvura ine yakanaka kumisa kugona, asi hapana chaiyo yepurasitiki deformation kukosha.
Kana iyo CMC yanyungudika, depolymerization inoitika chaizvo. Iyo viscosity inotanga kusimuka panguva yekuparara, inopfuura nepakati pepamusoro, uye yobva yadonha kune bani. Iyo inoguma viscosity ine hukama ne depolymerization.
Iyo dhigirii ye depolymerization inowirirana zvakanyanya nehuwandu hwehurombo hwekunyungudutsa (mvura) mukuumbwa. Mune isina kunaka yekunyungudutsa sisitimu, senge mushonga wemazino une glycerin nemvura, CMC haizonyatso depolymerize uye inosvika pakuenzana.
Panyaya yemvura yakapihwa, iyo yakanyanya hydrophilic inotsiva CMC iri nyore kuita depolymerize pane yakaderera inotsiva CMC.
Hydroxyethyl cellulose (HEC)
HEC inogadzirwa nekurapa donje rakanatswa nealkali, uyezve kuita ne ethylene oxide se etherification agent pamberi peacetone. Dhigirii rekutsiva kazhinji 1.5 ~ 2.0. Iyo ine yakasimba hydrophilicity uye iri nyore kutora unyoro.
Hydroxyethyl cellulose inonyungudika mumvura inotonhora, asi yakaoma kunyungudika mumvura inopisa. Mhinduro yaro yakagadzikana pakupisa kwepamusoro pasina gelling.
Yakagadzikana kune zvakajairika acids uye mabhesi. Alkalis inogona kukurumidza kuparara kwayo uye zvishoma kuwedzera viscosity yayo. Kupararira kwayo mumvura kwakashata zvishoma kupfuura iyo yemethyl cellulose uye hydroxypropyl methyl cellulose.
Hydroxypropyl Methyl Cellulose (HPMC)
Iyo molecular formula yeHPMC ndeye:
\[C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3\]n\]x
Hydroxypropyl methylcellulose imhando ye cellulose iyo kubuda kwayo uye kushandiswa kuri kuwedzera nekukurumidza.
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 zvaro zvakasiyana nekuda kweiyo reshiyo yakasiyana yemethoxyl yemukati uye hydroxypropyl yemukati.
Hydroxypropyl methylcellulose inonyungudika nyore nyore mumvura inotonhora, asi ichasangana nekunetseka 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.
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, iyo yakakwira viscosity ine yakaderera tembiricha mhedzisiro pane methyl cellulose. Mushonga waro wakagadzikana kana wakachengetwa pakushambidzika kwekamuri.
Kuchengetwa kwemvura kwehydroxypropyl methylcellulose kunoenderana nehuwandu hwayo hwekuwedzera, viscosity, nezvimwewo, uye chiyero chekuchengetedza mvura pachiyero chimwe chekuwedzera chakakwira kupfuura icho chemethyl cellulose.
Hydroxypropyl methylcellulose yakagadzikana kune acid uye alkali, uye mhinduro yayo ine aqueous yakagadzikana muhuwandu hwepH = 2 ~ 12. Caustic soda uye mvura yeraimu haina mhedzisiro pakuita kwayo, asi alkali inogona kukurumidzira kuparara kwayo uye kuwedzera viscosity yayo.
Hydroxypropyl methylcellulose yakagadzikana kune yakajairwa munyu, asi kana kusanganiswa kwemunyu munyu kwakakwira, viscosity yehydroxypropyl methylcellulose mhinduro inowedzera kuwedzera.
Hydroxypropyl methylcellulose inogona kusanganiswa nemvura-inonyungudika polymer komisheni kuita yunifomu uye yakakwirira viscosity mhinduro. Zvakadai se polyvinyl doro, starch ether, muriwo gum, nezvimwe.
Hydroxypropyl methylcellulose ine nani enzyme kuramba kupfuura methylcellulose, uye mhinduro yayo haine mukana wekuti inzymatic iparare kupfuura methylcellulose.
Nguva yekutumira: Feb-14-2023