I-Hydroxypropyl methylcellulose (HPMC) sisixhobo sepolymer esinyibilikayo emanzini esisetyenziswa kakhulu kumayeza, ukutya, ulwakhiwo kunye nezinye iinkalo. Sinozinzo oluhle lobushushu, kodwa sisenokuwohloka phantsi kobushushu obuphezulu. Ubushushu bokuwohloka kwe-HPMC buchaphazeleka kakhulu bulwakhiwo lwayo lweemolekyuli, iimeko zokusingqongileyo (ezifana nokufuma, ixabiso le-pH) kunye nexesha lokufudumeza.
Ubushushu bokubola kwe-HPMC
Ukwehla kobushushu be-HPMC kudla ngokuqala ukubonakala ngaphezulu kwama-200℃, kwaye ukubola okucacileyo kuya kwenzeka phakathi kwama-250℃-300℃Ngokukodwa:
Ngaphantsi kwe-100℃: I-HPMC ikakhulu ibonisa ukufuma kwamanzi kunye notshintsho kwiimpawu zomzimba, kwaye akukho kubola kwenzekayo.
100℃-200℃: I-HPMC inokubangela i-oxidation engaphelelanga ngenxa yokunyuka kobushushu bendawo, kodwa iyonke izinzile.
200℃-250℃: I-HPMC ibonisa kancinci kancinci ukonakala kobushushu, okubonakala kakhulu njengokuqhekeka kwesakhiwo kunye nokukhululwa kwezinto ezincinci eziguquguqukayo zemolekyuli.
250℃-300℃: I-HPMC ibola ngokucacileyo, umbala uba mnyama, iimolekyuli ezincinci ezifana namanzi, i-methanol, i-acetic acid ziyakhutshwa, kwaye kwenzeka i-carbonization.
Ngaphezulu kwama-300℃: I-HPMC ibola ngokukhawuleza kwaye i-carbonize, kwaye ezinye izinto ezingaphiliyo zihlala ekugqibeleni.
Izinto ezichaphazela ukonakala kwe-HPMC
Ubunzima beemolekyuli kunye nenqanaba lokutshintshwa
Xa ubunzima be-molecular ye-HPMC bukhulu, ukumelana kwayo nobushushu kudla ngokuba phezulu.
Umlinganiselo wokutshintshwa kwamaqela e-methoxy kunye ne-hydroxypropoxy uya kuchaphazela ukuzinza kobushushu bayo. I-HPMC enezinga eliphezulu lokutshintshwa ibola lula xa kushushu kakhulu.
Izinto ezisingqongileyo
Umswakama: I-HPMC ine-hygroscopicity enamandla, kwaye umswakama unokukhawulezisa ukuwohloka kwayo xa amaqondo obushushu ephezulu.
Ixabiso le-pH: I-HPMC isengozini enkulu yokuchithwa yi-hydrolysis kunye nokuwohloka phantsi kweemeko ze-asidi enamandla okanye i-alkali.
Ixesha lokufudumeza
Ukufudumeza ukuya kuma-250℃ixesha elifutshane lisenokungaboli ngokupheleleyo, ngelixa ukugcina ubushushu obuphezulu ixesha elide kuya kukhawulezisa inkqubo yokubola.
Iimveliso zokubola kwe-HPMC
I-HPMC ikakhulu ifumaneka kwi-cellulose, kwaye iimveliso zayo zokubola zifana ne-cellulose. Ngexesha lenkqubo yokufudumeza, oku kulandelayo kunokukhululwa:
Umphunga wamanzi (ovela kumaqela e-hydroxyl)
I-Methanol, i-ethanol (evela kumaqela e-methoxy kunye ne-hydroxypropoxy)
I-Acetic acid (evela kwiimveliso zokubola)
Ii-carbon oxides (CO2, CO2₂, eveliswa kukutsha kwezinto eziphilayo)
Inani elincinci le-coke residue
Ukumelana nobushushu besicelo se-HPMC
Nangona i-HPMC iza kuncipha kancinci kancinci ibe ngaphezulu kwama-200℃, ayisoloko ichaphazeleka kubushushu obuphezulu kangako xa isetyenziswa ngokwenene. Umzekelo:
Ishishini leMithi: I-HPMC isetyenziselwa ikakhulu ukugquma iipilisi kunye neearhente zokukhulula ixesha elide, zihlala zisebenza kwi-60℃-80℃, engaphantsi kakhulu kuneqondo lobushushu bayo lokuwohloka.
Ishishini lokutya: I-HPMC ingasetyenziswa njenge-thickener okanye i-emulsifier, kwaye ubushushu bokusetyenziswa kwesiqhelo abudluli kwi-100℃.
Ishishini lokwakha: I-HPMC isetyenziswa njengesithambisi sesamente kunye nodaka, kwaye ubushushu bokwakha ngokubanzi abudluli kuma-80℃, kwaye akukho konakala kuya kwenzeka.
I-HPMC iqala ukuwohloka ngobushushu obungaphezulu kwama-200℃, ibola kakhulu phakathi kwama-250℃-300℃kwaye i-carbonizes ikhawuleza ibe ngaphezulu kwama-300℃Kwimisebenzi ebonakalayo, kufuneka kuthintelwe ukuvezwa ixesha elide kwindawo enobushushu obuphezulu ukuze kugcinwe ukusebenza kwayo okuzinzileyo.
Ixesha leposi: Epreli-03-2025