Bayanan Bayani da Bayani
Cellulose ether shine kayan sinadarai masu kyau na polymer da aka yi amfani da su da yawa waɗanda aka yi daga cellulose na polymer na halitta ta hanyar magani. Bayan ƙera cellulose nitrate da cellulose acetate a cikin karni na 19, masana kimiyya sun haɓaka jerin abubuwan da suka samo asali na cellulose ethers da yawa, kuma an ci gaba da gano sababbin filayen aikace-aikacen, wanda ya ƙunshi sassa na masana'antu da yawa. Cellulose ether kayayyakin kamar sodiumCarboxymethyl cellulose (CMC), ethyl cellulose (EC), hydroxyethyl cellulose (HEC), hydroxypropyl cellulose (HPC), methyl hydroxyethyl cellulose (MHEC)kumamethyl hydroxypropyl cellulose (MHPC)da sauran ethers cellulose an san su da "monosodium glutamate masana'antu" kuma an yi amfani da su sosai wajen hako mai, gine-gine, sutura, abinci, magani da sinadarai na yau da kullum.
Hydroxyethyl methyl cellulose (MHPC) wani wari ne, marar ɗanɗano, farin foda mara guba wanda za'a iya narkar da shi cikin ruwan sanyi don samar da bayani mai haske. Yana da halaye na thickening, dauri, dispersing, emulsifying, film-forming, suspending, adsorbing, gelling, surface aiki, rike danshi da kuma kare colloid. Saboda saman aiki aiki na ruwa bayani, shi za a iya amfani da colloidal m wakili, emulsifier da dispersant. Hydroxyethyl methylcellulose aqueous bayani yana da kyau hydrophilicity kuma shi ne ingantaccen ruwa mai riƙe da ruwa. Saboda hydroxyethyl methylcellulose ya ƙunshi ƙungiyoyin hydroxyethyl, yana da kyakkyawan ikon rigakafin ƙwayar cuta, kwanciyar hankali mai kyau da juriya na mildew yayin ajiya na dogon lokaci.
An shirya Hydroxyethyl methylcellulose (HEMC) ta hanyar gabatar da abubuwan maye gurbin ethylene oxide (MS 0.3 ~ 0.4) a cikin methylcellulose (MC), kuma juriya na gishiri ya fi na polymers da ba a canza su ba. Yawan zafin jiki na methylcellulose shima ya fi na MC.
Tsarin
Siffar
Babban halayen hydroxyethyl methylcellulose (HEMC) sune:
1. Solubility: Mai narkewa a cikin ruwa da wasu kaushi na halitta. Ana iya narkar da HEMC a cikin ruwan sanyi. Mafi girman maida hankalinsa ana ƙaddara ta danko ne kawai. Solubility ya bambanta da danko. Ƙananan danko, mafi girma da solubility.
2. Juriya na Gishiri: Abubuwan HEMC ba su ne ethers cellulose na ionic ba kuma ba polyelectrolytes ba, don haka suna da kwanciyar hankali a cikin maganin ruwa lokacin da salts na ƙarfe ko kwayoyin halitta sun kasance, amma ƙari mai yawa na electrolytes na iya haifar da gelation da hazo.
3. Surface aiki: Saboda da surface aiki aiki na ruwa bayani, shi za a iya amfani da a matsayin colloidal m wakili, emulsifier da dispersant.
4. Thermal gel: Lokacin da ruwa mai ruwa na kayayyakin HEMC ya dumama zuwa wani yanayin zafi, ya zama opaque, gels, kuma precipitate, amma idan aka ci gaba da sanyaya, ya koma zuwa asali bayani yanayin, da kuma yawan zafin jiki a wanda wannan gel da hazo faruwa yawanci dangane da su lubricants, suspending aids, m colloids, emuls.
5. Rashin kuzari da rashin wari da kamshi: HEMC ana amfani da shi sosai wajen abinci da magunguna domin ba zai zama mai narkewa ba kuma yana da karancin kamshi da kamshi.
6. Juriya na Mildew: HEMC yana da ingantacciyar juriya mai kyau da kwanciyar hankali mai kyau a lokacin ajiya na dogon lokaci.
7. PH kwanciyar hankali: Danko na ruwa bayani na HEMC kayayyakin ba shi da wuya acid ko alkali ya shafa, kuma pH darajar ne in mun gwada da barga a cikin kewayon 3.0 zuwa 11.0.
Aikace-aikace
Hydroxyethyl methylcellulose za a iya amfani da a matsayin colloidal m wakili, emulsifier da dispersant saboda ta surface-aiki aiki a cikin ruwa bayani. Misalan aikace-aikacen sa sune kamar haka:
1. Tasirin hydroxyethyl methylcellulose akan aikin siminti. Hydroxyethyl methylcellulose wani wari ne, marar ɗanɗano, farin foda mara guba wanda za'a iya narkar da shi cikin ruwan sanyi don samar da bayani mai haske. Yana da halaye na thickening, dauri, dispersing, emulsifying, film-forming, suspending, adsorbing, gelling, surface aiki, rike danshi da kuma kare colloid. Tun da mai ruwa bayani yana da saman aiki aiki aiki, shi za a iya amfani da a matsayin colloidal m wakili, emulsifier da dispersant. Hydroxyethyl methylcellulose aqueous bayani yana da kyau hydrophilicity kuma shi ne ingantaccen ruwa mai riƙe da ruwa.
2. An shirya fenti mai sauƙi mai sauƙi, wanda aka yi da kayan albarkatun da aka yi a cikin sassa da nauyin nauyi: 150-200 g na ruwa mai tsabta; 60-70 g na acrylic emulsion mai tsabta; 550-650 g na alli mai nauyi; 70-90 g na talcum foda; Base cellulose ruwa bayani 30-40 g; lignocellulose ruwa bayani 10-20 g; Taimakon yin fim 4-6g; maganin rigakafi da fungicides 1.5-2.5 g; mai watsawa 1.8-2.2 g; wakilin wetting 1.8-2.2g; 3.5-4.5 g; Ethylene glycol 9-11 g; Ana yin maganin ruwa na hydroxyethyl methylcellulose ta hanyar narkar da 2-4% hydroxyethyl methylcellulose a cikin ruwa; Ana yin maganin ruwa na lignocellulose na 1-3% Lignocellulose ana yin shi ta hanyar narkewa cikin ruwa.
Shiri
Hanyar shiri na hydroxyethyl methyl cellulose, hanyar ita ce ana amfani da auduga mai ladabi azaman albarkatun ƙasa, kuma ana amfani da ethylene oxide azaman wakili na etherification don shirya hydroxyethyl methyl cellulose. The nauyi sassa na albarkatun kasa shirya hydroxyethyl methylcellulose ne kamar haka: 700-800 sassa na toluene da isopropanol cakuda kamar sauran ƙarfi, 30-40 sassa na ruwa, 70-80 sassa na sodium hydroxide, 80-85 sassa na mai ladabi auduga, zobe 20-28 sassa na oxy0-90 chloride sassa, 80-28 sassa na oxy0-90 chloride sassa, 80-28 sassa na oxy0-90 ethane, 8 chloride 19-1 methyl. glacial acetic acid; takamaiman matakai sune:
Mataki na farko, a cikin kettle dauki, ƙara toluene da cakuda isopropanol, ruwa, da sodium hydroxide, zafi har zuwa 60-80 ° C, dumi na minti 20-40;
Mataki na biyu, alkalization: sanyaya kayan da ke sama zuwa 30-50 ° C, ƙara auduga mai ladabi, fesa toluene da sauran kaushi na isopropanol, vacuumize zuwa 0.006Mpa, cika nitrogen don maye gurbin 3, da aiwatar da bayan maye gurbin Alkalinization, yanayin alkalization shine: lokacin alkalization shine 2 hours, kuma zafin jiki na 300C shine alkalization.
Mataki na uku, etherification: bayan an gama alkalization, ana fitar da reactor zuwa 0.05-0.07MPa, kuma an ƙara ethylene oxide da methyl chloride na minti 30-50; mataki na farko na etherification: 40-60 ° C, 1.0-2.0 Hours, ana sarrafa matsa lamba tsakanin 0.15 da 0.3Mpa; mataki na biyu na etherification: 60～90 ℃, 2.0～2.5 hours, da matsa lamba da ake sarrafawa tsakanin 0.4 da 0.8Mpa;
Mataki na hudu, neutralization: ƙara ma'auni glacial acetic acid a gaba zuwa hazo kettle, danna cikin etherified abu don neutralization, tada zafin jiki zuwa 75-80 ° C don hazo, da zazzabi ya tashi zuwa 102 ° C, da kuma pH darajar da aka gano zuwa 6 A karfe 8, da desolventization an kammala; tankin narkar da ruwa yana cike da ruwan famfo da na'urar osmosis na baya da aka bi da shi a 90 ° C zuwa 100 ° C;
Mataki na biyar, centrifugal wanka: kayan da ke cikin mataki na hudu an yi amfani da su ta hanyar centrifuge na kwance a kwance, kuma an canja kayan da aka raba zuwa wani tankin wanka da aka cika da ruwan zafi a gaba don wanke kayan;
Mataki na shida, bushewa na centrifugal: ana isar da kayan da aka wanke a cikin na'urar bushewa ta hanyar kwancen centrifuge a kwance, kuma an bushe kayan a 150-170 ° C, kuma busassun busassun an murƙushe su kuma an tattara su.
Idan aka kwatanta da fasahar samar da ether na cellulose, abin da aka kirkiro na yanzu yana amfani da ethylene oxide a matsayin wakili na etherification don shirya hydroxyethyl methyl cellulose, wanda ke da kyakkyawan juriya na mildew saboda yana dauke da kungiyoyin hydroxyethyl. Yana da kyau danko kwanciyar hankali da mildew juriya a lokacin dogon lokacin ajiya. Ana iya amfani dashi maimakon sauran ethers cellulose.
Lokacin aikawa: Afrilu-25-2024