Cov hydroxypropyl cellulose uas tsis muaj ntau yam hloov pauv (L-HPC) yog ib qho derivative ntawm cellulose, ib qho polymer ntuj pom muaj nyob rau hauv cov phab ntsa cell ntawm cov nroj tsuag. L-HPC tau raug hloov kho kom txhim kho nws cov solubility thiab lwm yam khoom, ua rau nws yog ib yam khoom siv ntau yam nrog ntau daim ntawv thov hauv kev lag luam tshuaj, khoom noj, thiab kev lag luam pleev xim.
Hydroxypropylcellulose uas tsis muaj kev hloov pauv ntau (L-HPC) yog ib qho cellulose derivative uas tsis muaj kev hloov pauv ntau uas tau hloov kho kom txhim kho nws cov solubility hauv dej thiab lwm yam solvents. Cellulose yog ib qho polysaccharide linear uas muaj cov glucose units uas muaj ntau nyob rau hauv xwm thiab yog ib qho khoom siv ntawm cov phab ntsa cell ntawm cov nroj tsuag. L-HPC yog synthesized los ntawm kev hloov kho cellulose, qhia txog hydroxypropyl pawg los txhim kho nws cov solubility thaum tswj qee qhov zoo ntawm cellulose.
Cov qauv tshuaj ntawm cov hydroxypropyl cellulose uas tsis tshua muaj hloov pauv
Cov qauv tshuaj ntawm L-HPC muaj cov cellulose backbone thiab hydroxypropyl pawg txuas rau hydroxyl (OH) pawg ntawm ib chav glucose. Qhov degree of substitution (DS) txhais tau hais tias tus lej nruab nrab ntawm hydroxypropyl pawg ib chav glucose hauv cov saw cellulose. Hauv L-HPC, DS raug khaws cia qis kom sib npaug zoo dua solubility nrog kev tswj cov khoom intrinsic ntawm cellulose.
Kev tsim cov hydroxypropyl cellulose uas tsis tshua muaj hloov pauv
Kev tsim cov L-HPC cuam tshuam nrog kev sib xyaw ntawm cellulose nrog propylene oxide nyob rau hauv qhov muaj cov tshuaj alkaline. Qhov kev sib xyaw no ua rau muaj cov pab pawg hydroxypropyl rau hauv cov saw hlau cellulose. Kev tswj hwm cov xwm txheej sib xyaw ua ke, suav nrog qhov kub thiab txias, lub sijhawm sib xyaw ua ke, thiab cov tshuaj catalyst concentration, yog qhov tseem ceeb kom ua tiav qib kev hloov pauv xav tau.
Cov yam tseem ceeb uas cuam tshuam rau kev yaj
1. Qib ntawm kev hloov pauv (DS):
Qhov solubility ntawm L-HPC raug cuam tshuam los ntawm nws cov DS. Thaum DS nce ntxiv, qhov hydrophilicity ntawm hydroxypropyl pawg ua rau pom tseeb dua, yog li txhim kho solubility hauv dej thiab cov kuab tshuaj polar.
2. Qhov hnyav ntawm cov molecule:
Qhov hnyav molecular ntawm L-HPC yog lwm yam tseem ceeb. Qhov hnyav molecular siab dua L-HPC yuav ua rau pom tias muaj kev yaj tsawg dua vim muaj kev sib cuam tshuam ntawm cov molecular thiab cov saw hlau sib txuas.
3. Kub:
Feem ntau qhov kev yaj yuav nce ntxiv nrog rau qhov kub thiab txias vim tias qhov kub siab dua muab zog ntau dua los rhuav tshem cov zog intermolecular thiab txhawb kev sib cuam tshuam ntawm polymer-solvent.
4. Tus nqi pH ntawm cov tshuaj:
Qhov pH ntawm cov tshuaj cuam tshuam rau qhov ionization ntawm cov pab pawg hydroxypropyl. Hauv qee kis, kev kho qhov pH yuav ua rau kom muaj kev yaj ntawm L-HPC ntau ntxiv.
5. Hom tshuaj yaj:
L-HPC ua rau pom tias nws yaj tau zoo hauv dej thiab ntau yam tshuaj yaj polar. Kev xaiv cov tshuaj yaj nyob ntawm seb siv rau qhov twg thiab cov khoom zoo li cas ntawm cov khoom kawg.
Daim ntawv thov ntawm cov hydroxypropyl cellulose uas tsis tshua muaj hloov pauv
1. Cov Tshuaj:
L-HPC siv dav hauv kev lag luam tshuaj ua tus binder, disintegrant thiab tswj kev tso tawm hauv cov tshuaj ntsiav. Nws cov solubility hauv cov kua hauv plab ua rau nws tsim nyog rau kev siv xa tshuaj.
2. Kev lag luam zaub mov:
Hauv kev lag luam khoom noj, L-HPC siv ua cov khoom ua kom tuab thiab ruaj khov hauv ntau yam khoom. Nws lub peev xwm los tsim cov gel ntshiab yam tsis cuam tshuam rau saj lossis xim ntawm cov khoom noj ua rau nws muaj txiaj ntsig zoo hauv cov qauv khoom noj.
3. Tshuaj pleev ib ce:
L-HPC siv rau hauv cov tshuaj pleev ib ce rau nws cov khoom ua zaj duab xis thiab ua kom tuab. Nws pab txhim kho qhov ruaj khov thiab cov qauv ntawm cov tshuaj pleev ib ce xws li tshuaj pleev, tshuaj pleev, thiab cov gels.
4. Daim ntawv thov txheej:
L-HPC siv tau ua cov khoom siv txheej zaj duab xis hauv kev lag luam tshuaj thiab khoom noj khoom haus los muab ib txheej tiv thaiv rau cov ntsiav tshuaj lossis cov khoom qab zib.
Hydroxypropyl cellulose uas tsis muaj ntau yam hloov pauv yog ib qho polymer ntau yam uas muaj kev yaj zoo dua los ntawm cov cellulose ntuj uas pom muaj nyob rau hauv cov nroj tsuag. Nws cov yam ntxwv tshwj xeeb ua rau nws muaj txiaj ntsig zoo hauv ntau yam lag luam suav nrog tshuaj, khoom noj thiab tshuaj pleev ib ce. Kev nkag siab txog cov yam ntxwv uas cuam tshuam rau nws qhov kev yaj yog qhov tseem ceeb rau kev ua kom zoo dua nws siv hauv ntau daim ntawv thov. Raws li kev tshawb fawb polymer thiab kev txhim kho txuas ntxiv mus, L-HPC thiab cov cellulose derivatives zoo sib xws yuav pom cov ntawv thov tshiab thiab tshiab hauv ntau qhov chaw.
Lub sijhawm tshaj tawm: Lub Kaum Ob Hlis-26-2023