Sodium carboxymethyl cellulose, inonzi carboxymethyl cellulose (CMC) imhando yepamusoro-polymer fiber ether inogadzirwa nekemikari shanduko yeyakasikwa cellulose. Chimiro chayo chinonyanya D-glucose unit kuburikidza ne β (1→ 4) Makiyi akabatanidzwa pamwechete.
CMC ichena kana mukaka chena fibrous poda kana granules, ine density ye 0.5-0.7 g/cm3, inenge isinganhuhwi, isinganakidze, uye hygroscopic. Inonyatso kuparadzirwa mumvura kuita inoonekera colloidal mhinduro, isinganyunguriki muorganic solvents senge ethanol. Iyo pH ye1% aqueous solution ndeye 6.5-8.5, kana pH> 10 kana <5, viscosity yemuchubhu inodzikira zvakanyanya, uye kuita ndiko kwakanyanya kana pH = 7. Yakagadzikana pakupisa, viscosity inokwira nekukurumidza pasi pe20 ° C, uye inoshanduka zvishoma nezvishoma pa45 ° C. Kupisa kwenguva refu pamusoro pe80 ° C kunogona kukanganisa colloid uye kuderedza zvakanyanya viscosity uye kushanda. Inonyungudika nyore nyore mumvura uye mhinduro yacho iri pachena; yakanyatsogadzikana mune alkaline solution, asi inonyorerwa nyore nyore hydrolyzed kana ikasangana neasidhi, uye inonaya kana pH kukosha iri 2-3, uye ichaitawo ne multivalent metal salts.
Chimiro chechimiro: C6H7(OH)2OCH2COONa Molecular formula: C8H11O5Na
Mhedzisiro huru ndeye: cellulose yechisikigo inotanga kusangana nealkalinization reaction neNaOH, uye nekuwedzera kwechloroacetic acid, iyo hydrogen paboka rehydroxyl paglucose unit inopindirana neiyo carboxymethyl boka mu chloroacetic acid. Zvinogona kuonekwa kubva muchimiro chechimiro kuti kune matatu mapoka ehydroxyl pane yega yega glucose unit, kureva, C2, C3, uye C6 hydroxyl mapoka. Iyo hydrogen paboka rega rega re hydroxyl inotsiviwa ne carboxymethyl, iyo inotsanangurwa sedhigirii yekutsiviwa kwe 3. Dhigirii yekutsiviwa kweCMC inobata zvakananga kunyungudika, emulsification, thickening, kugadzikana, asidi kuramba uye munyu.CMC .
Zvinowanzotendwa kuti kana dhigirii yekutsiva yakapoteredza 0.6-0.7, emulsifying performance iri nani, uye nekuwedzera kwedhigirii yekutsiva, zvimwe zvivakwa zvinovandudzwa zvinoenderana. Kana iyo dhigirii yekutsiva yakakura kupfuura 0.8, acid yayo kuramba uye munyu kuramba inowedzerwa zvakanyanya. .
Mukuwedzera, inotaurwawo pamusoro apa kuti kune mapoka matatu e-hydroxyl pane imwe neimwe unit, kureva, yechipiri hydroxyl mapoka eC2 neC3 uye yekutanga hydroxyl boka reC6. Muchirevo, basa rekutanga hydroxyl boka rakakura kudarika rechipiri hydroxyl boka, asi maererano ne isotopic effect yeC, iyo -OH boka paC2 Inowedzera acidic, kunyanya munharaunda yealkali yakasimba, basa rayo. yakasimba kudarika C3 neC6, saka inonyanya kutarisana nekugadzirisa maitiro, inoteverwa neC6, uye C3 ndiyo isina simba.
Muchokwadi, kuita kweCMC hakunechekuita chete nedhigirii rekutsiva, asiwo nekufanana kwekugoverwa kwemapoka ecarboxymethyl mune yese cellulose molecule uye kutsiviwa kwemapoka ehydroxymethyl muchikamu chimwe nechimwe chine C2, C3, uye C6 mu. molecule imwe neimwe. zvinoenderana nekufanana. Sezvo CMC iri yakanyanyisa polymerized linear komisheni, uye boka rayo recarboxymethyl rine inhomogeneous kutsiva mumorekuru, mamorekuru ane mativi akasiyana kana mhinduro yasara yakamira, uye kureba kwemutsetse molecule kwakasiyana kana paine simba rekugera mumhinduro. . Iyo axis ine tsika yekutendeukira kunzira yekuyerera, uye tsika iyi inova yakasimba nekuwedzera kweiyo shear rate kusvika iyo yekupedzisira kutungamira yarongeka zvachose. Ichi chimiro cheCMC chinonzi pseudoplasticity. Iyo pseudoplasticity yeCMC inobatsira kune homogenization uye pombi yekufambisa, uye haizoravira yakanyanyisa girisi mumukaka wemvura, izvo zvinoita kuti kuburitswa kwekunhuhwirira kwemukaka. .
Kuti tishandise zvigadzirwa zveCMC, isu tinofanirwa kuve nekunzwisisa kwakanaka kweiyo mikuru paramita senge kugadzikana, viscosity, acid kuramba, uye viscosity. Ziva kuti tinosarudza sei chigadzirwa chakanaka.
Yakaderera-viscosity CMC zvigadzirwa zvine inozorodza kuravira, yakaderera viscosity, uye anenge asina gobvu kunzwa. Iwo anonyanya kushandiswa mumasosi anokosha uye zvinwiwa. Utano hwezvinwiwa zvemukanwa zvakare isarudzo yakanaka.
Medium-viscosity CMC zvigadzirwa zvinonyanya kushandiswa muzvinwiwa zvakasimba, zvakajairwa mapuroteni zvinwiwa uye muto wemichero. Maitiro ekusarudza zvinoenderana nemaitiro ega einjiniya. Mukugadzikana kwezvinwiwa zvemukaka, CMC yakapa zvakawanda.
High-viscosity CMC zvigadzirwa zvine yakakura nzvimbo yekushandisa. Kuenzaniswa nestarch, guar gum, xanthan gum uye zvimwe zvigadzirwa, kugadzikana kweCMC kuchiri kuoneka, kunyanya muzvigadzirwa zvenyama, mukana wekuchengetedza mvura weCMC unonyanya kuoneka! Pakati pekudzikamisa senge ice cream, CMC zvakare isarudzo yakanaka.
Iwo makuru anoratidza kuyera kunaka kweCMC idhigirii rekutsiva (DS) uye kuchena. Kazhinji, zvinhu zveCMC zvakasiyana kana DS yakasiyana; iyo yakakwirira dhigirii yekutsiva, iyo yakasimba kunyungudika, uye zviri nani kuve pachena uye kugadzikana kwemhinduro. Sekureva kwemishumo, kujeka kweCMC kuri nani kana dhigirii rekutsiva iri 0.7-1.2, uye viscosity yemushonga wayo wemvura ndiyo yakakura kana iyo pH kukosha iri 6-9.
Kuti ive nechokwadi chemhando yayo, kunze kwesarudzo ye etherification agent, zvimwe zvinhu zvinokanganisa dhigirii rekutsiva uye kuchena zvinofanirwa kutariswa, sehukama pakati pehuwandu hwealkali uye etherification agent, etherification nguva, mvura yemukati. iyo system, tembiricha, kukosha kweDH, mhinduro Concentration uye munyu nezvimwe.
Hunhu hweCMC dzakapedzwa zvigadzirwa zvakanyanya zvinoenderana nemhinduro yechigadzirwa. Kana mhinduro yechigadzirwa ichijeka, kune mashoma gel particles, mahara fiber, uye mavara matema etsvina, zvinonyatsosimbiswa kuti mhando yeCMC yakanaka. Kana iyo mhinduro yakasara kwemazuva mashomanana, mhinduro haioneki. Ichena kana turbid, asi ichiri kujeka, icho chiri nani chigadzirwa!
Nguva yekutumira: Zvita-14-2022