Hydroxypropyl methylcellulose (Hypromellose), tseem hu ua hypromellose, yog dawb mus rau dawb cellulose hmoov los yog granule, uas muaj cov yam ntxwv ntawm soluble nyob rau hauv dej txias thiab insoluble nyob rau hauv dej kub zoo li methyl cellulose. Cov pab pawg hydroxypropyl thiab pawg methyl tau ua ke nrog lub nplhaib anhydrous qabzib ntawm cellulose los ntawm ether daim ntawv cog lus, uas yog ib hom non-ionic cellulose sib xyaw ether. Nws yog ib qho semisynthetic, tsis muaj zog, viscoelastic polymer feem ntau siv los ua cov roj nplua nyeem hauv ophthalmology, lossis ua ib qho khoom siv lossis tsheb hauv cov tshuaj hauv qhov ncauj.
kev npaj
Cov ntaub ntawv ntawm cov ntawv kraft ntawv tau los ntawm ntoo thuv nrog cov ntsiab lus alpha cellulose ntawm 97%, ib qho viscosity ntawm 720 ml / g, thiab qhov nruab nrab fiber ntau ntev ntawm 2.6 hli tau muab tso rau hauv 49% NaOH aqueous tov ntawm 40 ° C. 50 vib nas this; Lub resulting pulp yog ces nyem kom tshem tawm tshaj 49% aqueous NaOH kom tau alkali cellulose. Qhov hnyav piv ntawm (49% NaOH aqueous tov) rau (cov ntsiab lus hauv cov ntaub so ntswg) hauv cov kauj ruam impregnation yog 200. Qhov hnyav piv ntawm (cov ntsiab lus NaOH hauv alkali cellulose yog li tau) thiab (cov ntsiab lus hauv cov ntaub so ntswg) yog 1.49 ib. Cov alkali cellulose yog li tau txais (20 kg) tau muab tso rau hauv lub tsho siab siab reactor nrog rau sab hauv nplawm, ces tshem tawm thiab purged nrog nitrogen kom txaus tshem tawm cov pa tawm ntawm lub reactor. Tom qab ntawd, sab hauv stirring tau ua thaum tswj qhov kub hauv lub reactor mus rau 60 ° C. Tom qab ntawd, 2.4 kg ntawm dimethyl ether tau ntxiv, thiab qhov kub ntawm lub reactor raug tswj kom khaws cia ntawm 60 ° C. Tom qab ntxiv dimethyl ether, ntxiv dichloromethane kom cov molar ratio ntawm (dichloromethane) mus rau (NaOH tivthaiv nyob rau hauv alkaline cellulose) yog 1.3, thiab ntxiv propylene oxide los ua (propylene oxide) thiab (nyob rau hauv pulp) Qhov hnyav piv ntawm cov khoom muaj nqis) tau hloov mus rau 1.97, thaum qhov kub ntawm lub reactor tau tswj los ntawm 60 ° C mus rau 80 ° C. Tom qab ntxiv methyl chloride thiab propylene oxide, qhov kub ntawm lub reactor tau tswj los ntawm 80 ° C mus rau 90 ° C. Tsis tas li ntawd, cov tshuaj tiv thaiv tau txuas ntxiv ntawm 90 ° C rau 20 feeb. Tom qab ntawd, cov roj tau tso tawm los ntawm lub reactor, thiab tom qab ntawd cov crude hydroxypropyl methylcellulose raug tshem tawm ntawm lub reactor. Qhov kub ntawm cov crude hydroxypropyl methylcellulose thaum lub sij hawm tshem tawm yog 62 ° C. Qhov sib npaug 50% particle loj nyob rau hauv particle loj faib raws li cumulative hnyav txiav txim raws li qhov piv ntawm crude hydroxypropyl methylcellulose dhau los ntawm qhov qhib ntawm tsib sieves, txhua lub sieve muaj ib tug txawv qhib loj, yog ntsuas. Yog li ntawd, qhov nruab nrab particle loj ntawm coarse hais yog 6.2 hli. Yog li tau txais crude hydroxypropyl methylcellulose tau nkag mus rau hauv lub tshuab biaxial txuas ntxiv (KRC kneader S1, L / D = 10.2, sab hauv ntim 0.12 litres, rotational ceev 150 rpm) ntawm tus nqi ntawm 10 kg / hr, thiab decomposition tau. ntawm crude hydroxypropyl methylcellulose. Qhov nruab nrab particle loj yog 1.4 hli raws li ntsuas zoo sib xws siv sieves ntawm 5 qhov sib txawv qhov ntau thiab tsawg. Rau decomposed crude hydroxypropyl methylcellulose nyob rau hauv lub tank nrog lub tsho kub tswj, ntxiv dej kub ntawm 80 ° C nyob rau hauv ib tug npaum li ntawd (Qhov hnyav piv ntawm tus nqi ntawm cellulose) mus rau (tag nrho cov nyiaj ntawm slurry) tau hloov mus rau 0.1, thiab tau ib tug slurry. Lub slurry yog nplawm ntawm qhov kub thiab txias ntawm 80 ° C rau 60 feeb. Tom ntej no, cov slurry tau muab tso rau hauv lub preheated rotary siab lim (cov khoom ntawm BHS-Sonthofen) nrog kev sib hloov ceev ntawm 0.5 rpm. Qhov kub ntawm cov slurry yog 93 ° C. Lub slurry tau muab los ntawm lub twj tso kua mis, thiab qhov tso tawm siab ntawm lub twj tso kua mis yog 0.2 MPa. Qhov qhib qhov loj ntawm lub lim dej ntawm lub tshuab lim siab yog 80 μm, thiab qhov chaw pom yog 0.12 m 2. Lub slurry nkag mus rau lub tshuab lim siab hloov pauv mus rau lub ncuav mog qab zib lim los ntawm lim lim. Tom qab muab chav ntawm 0.3 MPa rau lub ncuav mog qab zib yog li tau, cov dej kub ntawm 95 ° C tau muab rau hauv qhov sib piv ntawm qhov hnyav ntawm (dej kub) rau (cov ntsiab lus ntawm hydroxypropyl methylcellulose tom qab ntxuav) yog 10.0, Tom qab ntawd, lim los ntawm lub lim. Cov dej kub tau muab los ntawm lub twj tso kua mis ntawm qhov tso tawm siab ntawm 0.2 MPa. Tom qab cov dej kub tau muab, chav ntawm 0.3 MPa tau muab. Tom qab ntawd, cov khoom ntxuav ntawm lub tshuab lim dej raug tshem tawm los ntawm scraper thiab tawm ntawm lub tshuab ntxhua khaub ncaws. Cov kauj ruam los ntawm kev pub cov slurry kom tso tawm cov khoom ntxuav yog ua tsis tu ncua. Raws li qhov tshwm sim ntawm kev ntsuas siv lub tshuab ziab khaub ncaws kom qhuav, cov ntsiab lus ntawm cov khoom ntxuav yog li 52.8%. Cov khoom ntxuav tawm tawm los ntawm lub tshuab lim dej tau qhuav siv lub tshuab ziab khaub ncaws ntawm 80 ° C., thiab pulverized nyob rau hauv ib qho kev cuam tshuam zeb Victory zeb kom tau hydroxypropyl methylcellulose.
daim ntawv thov
Cov khoom no yog siv los ua thickener, dispersant, binder, emulsifier thiab stabilizer hauv kev lag luam textile. Nws kuj yog siv dav hauv cov khoom siv hluavtaws, petrochemical, ceramics, ntawv, tawv, tshuaj, zaub mov, tshuaj pleev ib ce thiab lwm yam lag luam.
Post lub sij hawm: Nov-15-2022