Hydroxyethyl cellulose (HEC) ndi non-ionic cellulose ether yomwe imagwiritsidwa ntchito kwambiri pomanga, zokutira, mafuta, mankhwala a tsiku ndi tsiku ndi zina. Ili ndi makulidwe abwino, kuyimitsidwa, kubalalitsidwa, emulsification, kupanga filimu, zoteteza colloid ndi zinthu zina, ndipo ndizofunikira thickener ndi stabilizer.
1. Kukonzekera kwa zipangizo
Zopangira zazikulu za hydroxyethyl cellulose ndi cellulose yachilengedwe. Cellulose nthawi zambiri amachotsedwa ku nkhuni, thonje kapena zomera zina. The m'zigawo za mapadi ndi yosavuta, koma amafuna mkulu chiyero kuonetsetsa ntchito yomaliza mankhwala. Pachifukwa ichi, njira zamakina kapena zamakina nthawi zambiri zimagwiritsidwa ntchito popangira mankhwala a cellulose, kuphatikiza defatting, de-imprity, bleaching ndi njira zina zochotsera zonyansa ndi zida zopanda cellulose.
2. Alkalization mankhwala
Chithandizo cha alkalization ndi gawo lofunikira popanga hydroxyethyl cellulose. Cholinga cha sitepe iyi ndikuyambitsa gulu la hydroxyl (-OH) pa unyolo wa cellulose kuti muthandizire zomwe zimachitika motsatira etherification. Sodium hydroxide (NaOH) yankho nthawi zambiri amagwiritsidwa ntchito ngati alkalizing agent. Njira yeniyeni ndi: kusakaniza mapadi ndi sodium hydroxide yankho kuti kutupa kwathunthu ndi kumwaza mapadi pansi pa zinthu zamchere. Panthawiyi, magulu a hydroxyl pa ma cellulose amakhala otanganidwa kwambiri, akukonzekera zotsatira za etherification.
3. Etherification reaction
Etherification reaction ndiye gawo lofunikira popanga hydroxyethyl cellulose. Izi ndi kuyambitsa ethylene okusayidi (wotchedwanso ethylene okusayidi) kwa mapadi pambuyo mankhwala alkalinization, ndipo anachita ndi magulu hydroxyl mu mapadi mamolekyu kupanga hydroxyethyl mapadi. Zomwe zimachitika nthawi zambiri zimachitika mu riyakitala yotsekedwa, kutentha komwe kumayendetsedwa nthawi zambiri kumayendetsedwa pa 50-100 ° C, ndipo nthawi yake imakhala kuyambira maola angapo mpaka maola opitilira khumi. Chomaliza cha zomwe zimachitika ndi gawo la hydroxyethylated cellulose ether.
4. Kusalowerera ndale ndi kutsuka
Pambuyo etherification anachita anamaliza, ndi reactants kawirikawiri amakhala ndi kuchuluka kwa alkali osakhudzidwa ndi-zogulitsa. Kuti mupeze chopangidwa choyera cha hydroxyethyl cellulose, chithandizo cha neutralization ndi kutsuka chiyenera kuchitidwa. Kawirikawiri, kuchepetsa asidi (monga dilute hydrochloric acid) amagwiritsidwa ntchito kuti achepetse zotsalira za alkali zomwe zimachitika, ndiyeno zowonongeka zimatsuka mobwerezabwereza ndi madzi ambiri kuti zichotse zonyansa zosungunuka ndi madzi. Ma cellulose otsuka a hydroxyethyl alipo ngati keke yonyowa.
5. Kutaya madzi m'thupi ndi Kuyanika
Keke yonyowa ikatsuka imakhala ndi madzi ambiri ndipo imayenera kuchotsedwa ndi kuuma kuti ipeze mankhwala a hydroxyethyl cellulose. Kutaya madzi m'thupi kumachitika ndi kusefera kwa vacuum kapena kupatukana kwapakati kuti muchotse madzi ambiri. Pambuyo pake, keke yonyowa imatumizidwa ku zida zoyanika kuti ziume. Zipangizo zowumitsira wamba zimaphatikizapo zowumitsira ng'oma, zowumitsira ma flash ndi zowumitsa zopopera. Kutentha kowumitsa nthawi zambiri kumayendetsedwa pa 60-120 ℃ kuti tipewe kutentha kwambiri kuti zisapangitse kusintha kwazinthu kapena kuwonongeka kwa magwiridwe antchito.
6. Kupera ndi Kujambula
Ma cellulose owuma a hydroxyethyl nthawi zambiri amakhala chipika chachikulu kapena granular. Kuti zithandizire kugwiritsiridwa ntchito ndikuwongolera kufalikira kwa chinthucho, kuyenera kugwa ndikuwunikiridwa. Pogaya nthawi zambiri amagwiritsa ntchito chopukusira chomakina pogaya midadada ikuluikulu kukhala ufa wabwino. Screening ndi kulekanitsa coarse particles kuti safika chofunika tinthu kukula mu ufa wabwino kudzera zowonetsera ndi apertures osiyana kuonetsetsa yunifolomu fineness wa chomaliza mankhwala.
7. Kupaka katundu ndi Kusungirako
The hydroxyethyl mapadi mankhwala pambuyo akupera ndi kuwunika ali ndi fluidity ndi dispersibility, amene ali oyenera ntchito mwachindunji kapena processing zina. Chomalizacho chiyenera kupakidwa ndikusungidwa kuti chiteteze chinyezi, kuipitsidwa kapena kutulutsa okosijeni panthawi yoyendetsa ndi kusunga. Zida zopakira zotsimikizira chinyezi komanso anti-oxidation monga matumba a aluminiyamu zojambulazo kapena matumba amitundu yambiri nthawi zambiri amagwiritsidwa ntchito kulongedza. Pambuyo pakulongedza, mankhwalawa ayenera kusungidwa pamalo ozizira komanso owuma, kupewa kuwala kwa dzuwa komanso kutentha kwambiri komanso chinyezi chambiri kuti zitsimikizire kuti zimagwira ntchito bwino.
Kupanga kwa hydroxyethyl cellulose kumaphatikizapo kukonza zinthu zopangira, mankhwala alkalization, etherification reaction, neutralization ndi kutsuka, kutaya madzi m'thupi ndi kuyanika, kugaya ndi kuwunika, komanso kuyika komaliza ndi kusunga. Gawo lirilonse liri ndi zofunikira zake zapadera ndi mfundo zowongolera. Zomwe zimachitikira komanso zofunikira zogwirira ntchito ziyenera kuyendetsedwa mosamalitsa panthawi yopanga kuti zitsimikizidwe kuti ntchitoyo ndi yabwino komanso yokhazikika. Zinthu zambiri zama polima izi zimakhala ndi ntchito zosiyanasiyana pakupanga mafakitale komanso moyo watsiku ndi tsiku, kuwonetsa kufunikira kwake kosasinthika.
Nthawi yotumiza: Aug-21-2024