Ka kakaretso, ka ho kopanya hahydroxypropyl methylcellulose, selulose e hloekisitsoeng ea k'hothone e phekoloa ka tharollo ea alkali ho 35-40 ° C ka halofo ea hora, e petelitsoe, selulose e silafatsoa, 'me ka tsela e loketseng e tsofetse ho 35 ° C, e le hore likhoele tse fumanoeng tsa alkali li na le tekanyo ea polymerized ka hare ho sebaka se hlokahalang. Kenya fiber ea alkali ka har'a kettle ea etherification, eketsa propylene oxide le methyl chloride ka lehlakoreng le leng, 'me u etherify ho 50-80 ℃ lihora tse 5 ho khatello e phahameng ea hoo e ka bang 1.8 MPa. Ebe u eketsa palo e loketseng ea hydrochloric acid le oxalic acid ho metsi a chesang a 90 ° C ho hlatsoa thepa ho atolosa molumo. Dehydrate e nang le centrifuge. Hlatsoa ho fihlela u sa nke lehlakore, ha metsi a ka har'a thepa a le ka tlase ho 60%, o omise ka moea o chesang o tsoang ho 130 ° C ho ea tlase ho 5%.
Alkalization: K'hothone e hloekisitsoeng e phofshoana ka mor'a ho buloa e kenngoa ka har'a motsoako oa inert, 'me o kenngoa ka alkali le metsi a bonolo ho ruruha lesela la kristale la k'hothone e hloekisitsoeng, e leng se loketseng ho kenella ha limolek'hule tsa etherifying agent le ho ntlafatsa ho tšoana ha karabelo ea etherification. Alkali e sebelisoang ho alkalization ke tšepe ea hydroxide kapa setsi sa tlhaho. Palo ea alkali e ekelitsoeng (ka boima, e tšoanang ka tlase) ke makhetlo a 0.1-0.6 a k'hothone e hloekisitsoeng, 'me boholo ba metsi a bonolo ke makhetlo a 0.3-1.0 a k'hothone e hloekisitsoeng; solvent inert ke motsoako oa joala le hydrocarbon, 'me palo ea solvent inert e kenyelletsoeng ke k'hothone e hloekisitsoeng. 7-15 linako tse ling: solvent inert e ka boela ea e-ba joala bo nang le liathomo tsa carbon tse 3-5 (tse kang joala, propanol), acetone. E ka boela ea e-ba li-hydrocarbon tsa aliphatic le li-hydrocarbon tse nkhang hamonate; mocheso o lokela ho laoloa ka hare ho 0-35 ° C nakong ea alkalization; nako ea alkalization ke hoo e ka bang 1hr. Tokiso ea mocheso le nako e ka khethoa ho latela litlhoko tsa thepa le sehlahisoa.
Etherification: Ka mor'a phekolo ea alkalization, tlas'a maemo a vacuum, etherification e etsoa ka ho eketsa moemeli oa etherifying, 'me moemeli oa etherifying ke propylene oxide. E le ho fokotsa tšebeliso ea moemeli oa etherifying, moemeli oa etherifying o ile a eketsoa habeli nakong ea ts'ebetso ea etherification.
Nako ea poso: Apr-28-2024