Hydroxypropyl methyl cellulose HPMC, yomwe imadziwikanso kuti hydroxypromellose, ndi yoyera mpaka yoyera ya cellulose ether powder kapena granule yomwe imakhala ndi madzi ozizira komanso osasungunuka madzi otentha mofanana ndi methyl cellulose.Gulu la Hydroxypropyl ndi gulu la methyl ndi ether bond ndi mphete ya shuga ya anhydrous ya cellulose yophatikizidwa, ndi mtundu wa ether wopanda ionic cellulose.Ndi semi-synthetic, inactive, viscoelastic polima yomwe imagwiritsidwa ntchito ngati mafuta mu ophthalmology, kapena ngati chothandizira kapena chothandizira pamankhwala amkamwa.
1. Njira yopangira
Kraft zamkati zokhala ndi 97% ya cellulose, kukhuthala kwamkati kwa 720mL / g ndi kutalika kwa fiber 2.6mm kudaviikidwa mu 49% NaOH yankho pa 40 ℃ kwa masekondi 50.Kenako zamkati anali extruded kuchotsa owonjezera 49% NaOH njira kupeza zamchere mapadi.Kulemera kwa chiŵerengero cha (49% NaOH amadzimadzi njira) kuti (olimba chigawo cha zamkati) mu sitepe impregnation anali 200. Kulemera chiŵerengero cha NaOH mu alkali mapadi kuti olimba zamkati ndi 1.49.Ma cellulose a alkali omwe amapezedwa (20kg) amayikidwa mu cholumikizira choponderezedwa ndi kugwedezeka kwamkati, kenako amatsukidwa ndikutsukidwa ndi nayitrogeni kuti achotse mpweya wabwino kuchokera ku riyakitala.Kenako, kutentha kwa riyakitala kumayendetsedwa pa 60 ℃ pomwe kuyambitsa kwamkati kunkachitika.
Kenako 2.4kg dME idawonjezedwa ndipo kutentha mu riyakitala kumayendetsedwa mpaka 60 ℃.Pambuyo Kuwonjezera dimethyl efa, methylene mankhwala enaake anawonjezera kuti molar chiŵerengero cha methylene kolorayidi kuti NaOH mu zamchere mapadi 1.3, propylene okusayidi anawonjezera kuti kulemera chiŵerengero cha propylene okusayidi kuti olimba zamkati 1.97, ndi kutentha mu riyakitala. imayendetsedwa kuchokera ku 60 ℃ mpaka 80 ℃.Pambuyo powonjezera chloromethane ndi propylene oxide, kutentha kwa riyakitala kumayendetsedwa kuchokera ku 80 ℃ mpaka 90 ℃.Kuphatikiza apo, zomwe zidachitikazo zidatenga mphindi 20 pa 90 ℃.
The mpweya ndiye chatsanulidwa pa riyakitala ndi yosakongola hydroxypropyl methyl cellulose amachotsedwa riyakitala.Kutentha kwa hydroxypropyl methyl cellulose kunali 62 ℃.Kuyeza kuchuluka kwa 50% tinthu kukula mu cumulative kulemera zochokera tinthu kukula kugawa kutengera chiŵerengero cha hydroxypropyl methyl mapadi kudzera mipata asanu sieving, aliyense kukhala osiyana kutsegula kukula.
Zotsatira zake, pafupifupi tinthu kukula kwa coarse particles anali 6.2mm.The analandira yaiwisi hydroxypropyl methyl cellulose anadzetsa mosalekeza biaxial kneader (KRC kneader S1, L / D = 10.2, voliyumu mkati 0,12 L, kasinthasintha liwiro 150rpm) pa liwiro la 10kg/hr, ndi decomposed yaiwisi analandira hydroxypropyl methyl cellulose.Chifukwa cha miyeso yofananira pogwiritsa ntchito zowonera 5 zokhala ndi makulidwe osiyanasiyana otsegulira, pafupifupi kukula kwa tinthu kunali 1.4mm.Kuonjezera 80 ℃ madzi otentha ku crude hydroxypropyl methyl cellulose mu thanki ndi kutentha kwa jekete.kuchuluka kwa kulemera kwa chiŵerengero cha crude hydroxypropyl methyl cellulose ku chiwerengero chonse cha slurry ndi 0.1, ndipo slurry amapezeka.slurry imatenthedwa pa kutentha kosalekeza kwa 80 ℃ kwa mphindi 60.
Kenako, slurry imaperekedwa ku liwiro lozungulira la 0.5 RPM ndi preheated rotary pressure filter (BHS Sonthofen products).Kutentha kwa grout ndi 93 ℃.Gwiritsani ntchito mpope kuti mupereke slurry, kuthamanga kwa pampu ndi 0.2mpa.Kukula kotsegulira kwa fyuluta yamagetsi ya rotary ndi 80μm, ndipo malo osefa ndi 0.12m2.Slurry yomwe imaperekedwa ku fyuluta ya rotary pressure imasefedwa kudzera mu fyuluta ndikusinthidwa kukhala keke ya fyuluta.Keke yotsatiridwayo imaperekedwa ndi nthunzi ya 0.3mpa ndi madzi otentha 95 ℃ okhala ndi chiyerekezo cha kulemera kwa 10.0 ku gawo lolimba la HYDROXYpropyl methyl cellulose, yomwe imasefedwa kudzera mu fyuluta.
Madzi otentha amaperekedwa kudzera pa mpope pa kuthamanga kwa 0.2mpa.Madzi otentha akaperekedwa, nthunzi ya 0.3mpa imaperekedwa.Ndiye, pambuyo kutsuka mankhwala amachotsedwa pa fyuluta pamwamba ndi scraper ndi kutulutsidwa kunja kwa makina ochapira.Masitepe kuchokera pakupereka slurry mpaka kutulutsa zinthu zotsuka zimachitidwa mosalekeza.Monga momwe amayezera pogwiritsa ntchito kutentha - kuyanika hygrometer, madzi omwe adatsukidwa adatulutsidwa anali 52.8%.Zinthu zotsukidwa zomwe zimatulutsidwa mu fyuluta ya rotary zowumitsidwa ndi chowumitsira mpweya pa 80 ℃, ndikuphwanyidwa mu chigayo cha Victory kuti mupeze hydroxypropyl methyl cellulose.
2.Akupempha
HPMC mankhwala ntchito thickener, dispersant, binder, emulsifier ndi stabilizer mu makampani nsalu.Amagwiritsidwanso ntchito popanga utomoni, petrochemical, ceramic, pepala, zikopa, mankhwala, chakudya, zodzoladzola ndi mafakitale ena.
Nthawi yotumiza: Mar-23-2022