Hydroxypropyl cellulose (HPC) yog ib qho khoom siv polymer hauv ntau yam lag luam, suav nrog tshuaj, tshuaj pleev ib ce, thiab zaub mov.Zoo li ntau cov polymers, nws cov thermal stability thiab degradation kub nyob ntawm ntau yam xws li qhov hnyav molecular, qib ntawm kev hloov pauv, muaj cov khoom ntxiv, thiab kev ua haujlwm.Txawm li cas los xij, kuv yuav muab rau koj nrog cov ntsiab lus ntawm cov xwm txheej cuam tshuam rau cov thermal degradation ntawm HPC, nws qhov kub thiab txias degradation ntau, thiab qee qhov ntawm nws cov ntawv thov.
1. Chemical Structure ntawm HPC:
Hydroxypropyl cellulose yog derivative ntawm cellulose tau los ntawm kev kho cellulose nrog propylene oxide.Qhov kev hloov kho tshuaj no qhia txog kev solubility thiab lwm yam khoom tsim nyog rau cellulose, ua rau nws muaj txiaj ntsig hauv ntau daim ntawv thov.
2. Tej yam cuam tshuam rau Thermal Degradation:
ib.Molecular Luj: Siab molecular hnyav HPC nyhav kom muaj thermal stability ntau dua vim muaj zog intermolecular rog.
b.Degree of Hloov (DS): Qhov kev hloov pauv ntawm hydroxypropyl cuam tshuam qhov thermal stability ntawm HPC.DS siab dua tuaj yeem ua rau qis qis qis vim qhov muaj qhov tsis zoo rau thermal cleavage.
c.Muaj Cov Khoom Ntxiv: Qee cov tshuaj ntxiv tuaj yeem txhim kho qhov thermal stability ntawm HPC los ntawm kev ua cov stabilizers lossis antioxidants, thaum lwm tus tuaj yeem ua kom lub zog degradation.
d.Cov Txheej Txheem Ua Haujlwm: Cov xwm txheej raws li HPC tau ua tiav, xws li kub, siab, thiab raug huab cua lossis lwm qhov chaw ua haujlwm, tuaj yeem cuam tshuam rau nws cov thermal stability.
3. Thermal Degradation Mechanism:
Lub thermal degradation ntawm HPC feem ntau cuam tshuam nrog kev tawg ntawm glycosidic daim ntawv cog lus nyob rau hauv cov pob txha cellulose thiab cov cleavage ntawm ether linkages qhia los ntawm hydroxypropyl hloov.Cov txheej txheem no tuaj yeem ua rau tsim cov khoom tsis hloov pauv xws li dej, carbon dioxide, thiab ntau yam hydrocarbons.
4. Hom Degradation Temperature Range:
Qhov kub degradation ntawm HPC tuaj yeem sib txawv dav nyob ntawm seb cov xwm txheej tau hais los saum toj no.Feem ntau, thermal degradation ntawm HPC pib nyob ib ncig ntawm 200 ° C thiab tej zaum yuav mus txog rau qhov kub ntawm 300-350 ° C.Txawm li cas los xij, qhov ntau yam no tuaj yeem hloov pauv nyob ntawm cov yam ntxwv tshwj xeeb ntawm HPC qauv thiab cov xwm txheej uas nws raug.
5. Kev siv ntawm HPC:
Hydroxypropyl cellulose pom daim ntawv thov nyob rau hauv ntau yam lag luam:
ib.Pharmaceuticals: Nws yog siv los ua thickener, binder, zaj duab xis qub, thiab tswj-tso tus neeg saib xyuas hauv cov tshuaj formulations xws li ntsiav tshuaj, tshuaj ntsiav, thiab tshuaj pleev.
b.Tshuaj pleev ib ce: HPC yog siv nyob rau hauv cov tshuaj pleev ib ce thiab cov khoom tu tus kheej raws li ib tug thickening neeg sawv cev, stabilizer, thiab zaj duab xis yav dhau los nyob rau hauv cov khoom xws li tshuaj pleev ib ce, cream, thiab tu plaub hau formulations.
c.Kev lag luam khoom noj khoom haus: Hauv kev lag luam khoom noj, HPC ua hauj lwm ua cov thickener, stabilizer, thiab emulsifier hauv cov khoom xws li kua ntses, kua zaub, thiab khoom qab zib.
d.Cov ntawv thov kev lag luam: HPC tseem ua haujlwm rau ntau yam kev lag luam xws li inks, coatings, thiab adhesives vim nws cov yeeb yaj kiab tsim thiab rheological zog.
Lub thermal degradation kub ntawm hydroxypropyl cellulose nws txawv nyob ntawm seb yam xws li qhov hnyav molecular, degree ntawm kev hloov, muaj cov additives, thiab ua tej yam kev mob.Thaum nws qhov degradation feem ntau pib ntawm 200 ° C, nws tuaj yeem txuas mus rau qhov kub ntawm 300-350 ° C.Kev nkag siab txog yam cuam tshuam rau nws cov thermal stability yog qhov tseem ceeb rau kev ua kom zoo dua nws cov kev ua tau zoo hauv ntau daim ntawv thov thoob plaws kev lag luam sib txawv.
Post lub sij hawm: Mar-26-2024