Hydroxyethyl cellulose (HEC) ba ionic ba ne, polymer mai narkewa da ruwa wanda aka samu daga cellulose, polymer na halitta da aka samu a bangon tantanin halitta. Ana amfani da shi sosai a masana'antu daban-daban, ciki har da magunguna, kayan kwalliya, fenti, da adhesives, saboda kyakkyawan kauri, ƙirƙirar fim, da halayen rheological. Shirye-shiryen hydroxyethyl cellulose ya haɗa da etherification na cellulose tare da ethylene oxide a ƙarƙashin yanayin alkaline. Za a iya raba wannan tsari zuwa matakai masu mahimmanci: tsarkakewar cellulose, alkalization, etherification, neutralization, wanke, da bushewa.
1. Tsaftace Cellulose
Mataki na farko a cikin shirye-shiryen hydroxyethyl cellulose shine tsarkakewar cellulose, yawanci ana samo shi daga ɓangaren litattafan itace ko auduga. Raw cellulose ya ƙunshi ƙazanta irin su lignin, hemicellulose, da sauran abubuwan cirewa waɗanda dole ne a cire su don samun cellulose mai tsabta mai tsabta wanda ya dace da gyaran sinadarai.
Matakan da ke ciki:
Sarrafa Injini: Ana sarrafa ɗanyen cellulose da injina don rage girmansa da ƙara sararin samansa, yana sauƙaƙe jiyya na sinadarai na gaba.
Maganin sinadarai: Ana maganin cellulose da sinadarai irin su sodium hydroxide (NaOH) da sodium sulfite (Na2SO3) don wargaza lignin da hemicellulose, sannan a yi wanka da bleaching don cire sauran ƙazanta da samun farin cellulose mai fibrous.
2. Alkalisation
Selulose da aka tsarkake sannan aka sanya alkalized don kunna shi don amsawar etherification. Wannan ya ƙunshi maganin cellulose tare da maganin ruwa na sodium hydroxide.
Martani:
Cellulose+NaOH→Alkali cellulose
Tsari:
An dakatar da cellulose a cikin ruwa, kuma an ƙara maganin sodium hydroxide. Matsakaicin NaOH yawanci jeri daga 10-30%, kuma ana aiwatar da martani a yanayin zafi tsakanin 20-40 ° C.
Ana zuga cakuda don tabbatar da ɗaukar alkali iri ɗaya, wanda ke haifar da samuwar alkali cellulose. Wannan tsaka-tsakin ya fi mayar da martani ga ethylene oxide, yana sauƙaƙe tsarin etherification.
3. Etherification
Babban mataki a cikin shirye-shiryen hydroxyethyl cellulose shine etherification na alkali cellulose tare da ethylene oxide. Wannan halayen yana gabatar da ƙungiyoyin hydroxyethyl (-CH2CH2OH) a cikin kashin bayan cellulose, yana mai da shi ruwa mai narkewa.
Martani:
Alkali cellulose+Ethylene oxide→Hydroxyethyl cellulose+NaOH
Tsari:
Ana ƙara Ethylene oxide zuwa alkali cellulose, ko dai a cikin tsari ko ci gaba. Yawanci ana gudanar da martanin a cikin na'urar motsa jiki ta autoclave ko matsa lamba.
Yanayin halayen, gami da zafin jiki (50-100 ° C) da matsa lamba (1-5 ATM), ana sarrafa su a hankali don tabbatar da mafi kyawun maye gurbin ƙungiyoyin hydroxyethyl. Matsayin maye gurbin (DS) da maye gurbin molar (MS) sune mahimman sigogi waɗanda ke tasiri ga kaddarorin samfurin ƙarshe.
4. Neutralization
Bayan amsawar etherification, cakuda ya ƙunshi hydroxyethyl cellulose da ragowar sodium hydroxide. Mataki na gaba shine neutralization, inda alkali ya wuce gona da iri ya zama neutralized ta amfani da acid, yawanci acetic acid (CH3COOH) ko hydrochloric acid (HCl).
Amsa:NaOH+HCl→NaCl+H2O
Tsari:
Ana ƙara acid ɗin sannu a hankali zuwa gaurayar amsawa a ƙarƙashin yanayin sarrafawa don gujewa zafi mai yawa da hana lalatawar hydroxyethyl cellulose.
Ana sanya cakudawar da ba ta dace ba don daidaita pH don tabbatar da yana cikin kewayon da ake so, yawanci a kusa da pH tsaka tsaki (6-8).
5. Wanka
Bayan neutralization, dole ne a wanke samfurin don cire gishiri da sauran abubuwan da aka gyara. Wannan mataki yana da mahimmanci don samun tsarkin hydroxyethyl cellulose.
Tsari:
A dauki cakuda da aka diluted da ruwa, da kuma hydroxyethyl cellulose rabu da tacewa ko centrifugation.
Ana maimaita wanke hydroxyethyl cellulose da ke rabu da ruwa mai lalacewa don cire ragowar gishiri da ƙazanta. Ana ci gaba da aikin wankewa har sai ruwan wanka ya kai ga ƙayyadadden ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun ƙayyadaddun abubuwa, yana nuna kawar da datti mai narkewa.
6. Bushewa
Mataki na ƙarshe a cikin shirye-shiryen hydroxyethyl cellulose yana bushewa. Wannan matakin yana kawar da wuce haddi da ruwa, samar da bushe, foda samfurin dace da daban-daban aikace-aikace.
Tsari:
Ana bazuwar hydroxyethyl cellulose da aka wanke akan busassun tire ko isar da shi ta rami mai bushewa. Ana sarrafa zafin jiki na bushewa a hankali don guje wa lalatawar thermal, yawanci jere daga 50-80 ° C.
A madadin, ana iya amfani da bushewar feshi don bushewa cikin sauri da inganci. A cikin bushewar bushewa, maganin hydroxyethyl cellulose na ruwa mai ruwa yana jujjuya shi cikin ɗigon ruwa masu kyau kuma a bushe a cikin rafin iska mai zafi, yana haifar da foda mai kyau.
Ana niƙa busasshen samfurin zuwa girman ɓawon da ake so kuma a kwashe don ajiya da rarrabawa.
Kula da inganci da Aikace-aikace
A cikin tsarin shirye-shiryen, ana aiwatar da matakan kulawa mai mahimmanci don tabbatar da daidaito da ingancin hydroxyethyl cellulose. Mahimmin sigogi kamar danko, matakin maye gurbin, abun cikin danshi, da girman barbashi ana kulawa akai-akai.
Aikace-aikace:
Pharmaceuticals: Ana amfani da shi azaman wakili mai kauri, ɗaure, da stabilizer a cikin tsari kamar allunan, dakatarwa, da man shafawa.
Kayan shafawa: Yana ba da danko da rubutu ga samfuran kamar creams, lotions, da shampoos.
Paints da Coatings: Ayyukan aiki azaman thickener da rheology modifier, inganta aikace-aikacen Properties da kwanciyar hankali na fenti.
Masana'antar Abinci: Ayyuka azaman thickener, stabilizer, da emulsifier a cikin samfuran abinci daban-daban.
Shirye-shiryen hydroxyethyl cellulose ya ƙunshi jerin ingantattun sinadarai da matakan injiniya da nufin canza cellulose don gabatar da ƙungiyoyin hydroxyethyl. Kowane mataki, daga tsarkakewar cellulose zuwa bushewa, yana da mahimmanci wajen tantance inganci da aikin samfurin ƙarshe. Abubuwan da ke tattare da hydroxyethyl cellulose sun sa ya zama wani abu mai mahimmanci a cikin masana'antu da yawa, yana nuna mahimmancin ingantattun ayyukan masana'antu don saduwa da takamaiman buƙatun aikace-aikace daban-daban.
Lokacin aikawa: Mayu-28-2024