Hydroxypropyl methylcellulose (Hypromellose), oo sidoo kale loo yaqaano hypromellose, waa budada cellulose ama granule cad ama cad, kaas oo leh sifooyinka lagu milmo biyo qabow oo aan lagu milmin biyaha kulul ee la mid ah methyl cellulose. Kooxda hydroxypropyl iyo kooxda methyl waxaa lagu daraa giraanta gulukooska anhydrous ee cellulose by ether bond, kaas oo ah nooc ka mid ah unugyada isku qasan ee cellulose. Waa semisynthetic, aan firfircoonayn, polymer viscoelastic oo caadi ahaan loo isticmaalo saliidaha indhaha, ama qalab ahaan ama gaadiid ahaan dawooyinka afka.
diyaarinta
Saxarka xaashida ee saxarka warqadda kraft ee laga helay alwaax alfa cellulose ah oo ka kooban 97%, viscosity gudaha ah 720 ml/g, iyo celceliska dhererka fiber-ka ee 2.6 mm ayaa lagu dhex milmay 49% NaOH aqueous solution at 40°C 50 ilbiriqsi; Saxarka ka soo baxay ayaa markaa la tuujiyey si looga saaro 49% aqueous NaOH si loo helo cellulose alkali ah. Saamiga miisaanka ee (49% NaOH xal aqueous) ilaa (content adag in saxarka) ee tallaabada impregnation ahaa 200. 1.49. cellulose-ka alkali-ka ah ee sidaas lagu helay (20 kg) ayaa lagu dhejiyay reactor-ka cadaadiska jaakada leh oo kicin gudaha ah, ka dibna la daadgureeyay oo lagu nadiifiyay nitrogen si si waafi ah looga saaro ogsijiinta fal-celinta. Marka xigta, walaaq gudaha ah ayaa la sameeyay iyadoo la xakameynayo heerkulka ku jira reactor ilaa 60 ° C. Kadib, 2.4 kg oo dimethyl ether ah ayaa lagu daray, heerkulka ku jira reactor-ka ayaa la kontaroolay si loogu ilaaliyo 60 ° C. Ka dib marka lagu daro dimethyl ether, ku dar dichloromethane si saamiga molar ee (dichloromethane) ilaa (Qaybta NaOH ee cellulose alkaline) waa 1.3, oo ku dar propylene oxide si aad u sameyso (propylene oxide) iyo (in saxarka) Saamiga miisaanka maadada adag) waxaa loo beddelay 1.97, halka heerkulka ku jira reactor-ka laga xakameeyay 60 ° C ilaa 80 ° C. Ka dib marka lagu daro methyl chloride iyo propylene oxide, heerkulka ku jira reactor-ka waxaa la xakameeyey 80 ° C ilaa 90 ° C. Intaa waxaa dheer, falcelinta ayaa lagu sii waday 90 ° C 20 daqiiqo. Kadib, gaaska ayaa laga soo saaray reactor-ka, ka dibna waxaa laga soo saaray reactor-ka hydroxypropyl methylcellulose cayriin. Heerkulka hydroxypropyl methylcellulose cayriin wakhtiga la soo saarayay wuxuu ahaa 62 digrii C. Baaxadda walxaha 50% ee qaybinta cabbirka walxaha ku salaysan miisaanka isugaynta ee la go'aamiyay iyadoo lagu salaynayo saamiga hydroxypropyl methylcellulose cayriin ee maraaya furayaasha shan shaandheeyo, shaandho kasta oo leh cabbir furan oo kala duwan, ayaa la qiyaasay. Natiijo ahaan, celceliska cabbirka qayb ka mid ah qaybaha aan fiicneyn wuxuu ahaa 6.2 mm. Sidaa darteed la helay hydroxypropyl methylcellulose ceyriin ah ayaa lagu soo bandhigay cajiinka biaxial joogto ah (KRC kneader S1, L/D = 10.2, mugga gudaha 0.12 litir, xawaaraha wareega 150 rpm) ee heerka 10 kg / hr, iyo burburka ayaa la helay. ee hydroxypropyl methylcellulose cayriin. Celcelis ahaan cabbirka walxaha wuxuu ahaa 1.4 mm sida lagu qiyaasay si isku mid ah iyadoo la isticmaalayo shaandho 5 cabbir kala duwan ah. Si aad u qurmay hydroxypropyl methylcellulose ceyriin ee taangiga leh heerkulka jaakada, ku dar biyo kulul at 80 ° C in qadar sida (Samiga miisaanka ee qadarka cellulose) ilaa (wadarta xadiga slurry) waxaa loo beddelay 0.1, iyo slurry ayaa la helay. Soodhaha ayaa lagu walaaqay heerkul joogto ah oo ah 80 ° C 60 daqiiqo. Marka xigta, slurry-ga waxaa lagu quudiyay shaandhada cadaadiska wareegga hore ee kuleylka ah (wax soo saarka BHS-Sonthofen) oo leh xawaare wareeg ah 0.5 rpm. Heerkulka slurry wuxuu ahaa 93 ° C. Biyo-mareenka waxaa lagu keenay iyadoo la adeegsanayo bamka, cadaadiska dheecaanka bamka wuxuu ahaa 0.2 MPa. Baaxadda furitaanka shaandhada shaandhada cadaadiska wareega waxay ahayd 80 μm, aagga shaandhayntana waxay ahayd 0.12 m 2. slurry-ka la keeno shaandhada cadaadiska wareega ayaa loo beddelaa kee shaandhayn iyadoo sifaysan shaandhayn. Ka dib markii la siiyo uumi ah 0.3 MPa keega sidaas la helay, biyaha kulul ee 95 ° C ayaa la keenay xaddi in saamiga miisaanka (biyaha kulul) ilaa (content adag ee hydroxypropyl methylcellulose ka dib markii la dhaqay) ahaa 10.0, ka dibna, sifee iyada oo loo marayo filtarka. Biyaha kulul waxaa lagu keenay bamka cadaadiska dareeraha ah ee 0.2 MPa. Ka dib markii biyaha kulul la keenay, uumiga 0.3 MPa ayaa la keenay. Kadib, alaabta la dhaqay ee dusha shaandhada ayaa laga saarayaa xoqo oo laga soo saaraa mashiinka dharka. Tallaabooyinka laga bilaabo quudinta dareeraha ilaa soo daynta alaabta la dhaqay si joogto ah ayaa loo fuliyaa. Natiijadu waxay tahay cabbiraadda iyadoo la isticmaalayo nooca hygrometer-ku-qallajinta kulaylka, nuxurka biyaha ee alaabta la dhaqay ee sidaas lagu sii daayay waxay ahayd 52.8%. Alaabta la dhaqay ee laga soo saaray shaandhada cadaadiska wareega ayaa la engejiyey iyadoo la isticmaalayo qalajiyaha hawada 80° C., waxaana lagu miiray warshad wax-qabad leh si loo helo hydroxypropyl methylcellulose.
codsi
Alaabtan waxaa loo isticmaalaa sidii dhumucdiye, kala firdhiye, binder, emulsifier iyo xasiliyaha warshadaha dharka. Waxa kale oo si weyn loogu isticmaalaa xabagta synthetic, petrochemical, ceramics, waraaqaha, maqaarka, daawada, cuntada, qurxinta iyo warshadaha kale.
Waqtiga boostada: Nov-15-2022