Thonje woyengedwa-kutsegula-alkalization-etherification-neutralization-kupatukana-kutsuka-kupatukana-kuyanika-kuphwanyidwa-kuyika-kumaliza kutsegulidwa kwa mankhwala a HPMC: Thonje loyengedwa limatsegulidwa kuchotsa chitsulo kenako n'kuphwanyidwa. Thonje woyengedwa woyengedwa uli ngati ufa, wokhala ndi tinthu tating'ono ting'onoting'ono 80 mesh ndi transmittance 100%. Apo ayi, n'zosavuta coalesce pamodzi pa ndondomeko anachita ndi kuchepetsa etherification dzuwa.
Alkalization: Onjezani thonje la ufa woyengedwa pambuyo pa kutsegulidwa kwa thonje ku chosungunulira cha inert, ndikuyambitsa ndi alkali ndi madzi ofewa kuti mufufuze matope a thonje woyengedwa kuti mulowetse mamolekyu a etherification ndikusintha kufanana kwa etherification reaction. The alkali ntchito alkalization ndi zitsulo hydroxide kapena organic alkali. Kuchuluka kwa alkali kuwonjezeredwa (ndi misa, momwemonso pansipa) ndi 0.1-0.6 nthawi ya thonje yoyengedwa, kuchuluka kwa madzi ofewa owonjezera ndi 0.3-1.0 nthawi ya thonje yoyengedwa; zosungunulira inert ndi chisakanizo cha mowa ndi hydrocarbon, ndipo kuchuluka kwa inert zosungunulira anawonjezera ndi 0.3-1.0 nthawi ya thonje woyengedwa. 7 -15 nthawi za izo: Chosungunulira cha inert chingakhalenso mowa wokhala ndi maatomu a carbon 3-5 (monga mowa, propanol), acetone. Itha kukhalanso ma hydrocarbon aliphatic ndi ma hydrocarbon onunkhira; kutentha kuyenera kuyendetsedwa mkati mwa 0-35 ° C panthawi ya alkalization; nthawi ya alkalization ndi pafupifupi 1hr. Kusintha kwa kutentha ndi nthawi kungadziwike molingana ndi zofunikira zakuthupi ndi mankhwala.
Etherification: Pambuyo pa chithandizo cha alkalization, pansi pazimenezi, wothandizira etherification amawonjezedwa kwa etherification, ndipo wothandizira ndi propylene oxide. Pofuna kuchepetsa kugwiritsidwa ntchito kwa etherification wothandizira, panthawi ya etherification, wothandizira etherification amawonjezeredwa kawiri, kuchuluka kwa kuwonjezera koyamba ndi 1-3.5 nthawi ya thonje woyengedwa, ndipo kuchuluka kwa zowonjezera ziwirizo ndi 1.5 - 4 nthawi ya thonje woyengedwa. nthawi. Pambuyo powonjezera etherifying wothandizira kwa nthawi yoyamba, yambitsani pa ≤30 ° C kwa 45min-90min, kenaka kwezani kutentha kwa 50-100 ° C kwa etherification kwa 1-5h, kenako kuzizira mpaka ≤30 ° C, kachiwiri. kuwonjezera etherification oyambitsa, oyambitsa nthawi ndi 30-120min, ndiyeno mkangano kuti? ? ? Chitani etherification, nthawi ndi 1-4h, panthawiyi, thonje woyengedwa bwino amakumana ndi etherification agent kuti apange hYDROXYPROPYL METHYLCELLULOSE HPMC.
Kuphwanya ndi kulongedza: kuphwanya ndi kusefa zouma zomwe zapangidwa pano, kukula kwa tinthu tating'ono ta HPMC zomwe zidapangidwa pano pambuyo pophwanya ndi kusefa ndi ma mesh 40 ndipo transmittance ndi 10096, kapena malinga ndi zosowa za ogwiritsa ntchito. Kenako pangani HPMC.
Nthawi yotumiza: Nov-24-2022