Taulai atu ile Cellulose ethers

E fa'apefea ona faia le hydroxypropylcellulose?

O le Hydroxypropylcellulose (HEC) o se mea e maua mai i le cellulose, o se polymer masani o loʻo maua i totonu o puipui o laau. O le HPC o lo'o fa'aaogaina lautele i pisinisi eseese e pei o vaila'au, mea teuteu ma fale mea'ai ona o le lelei tele o mea e fai ai ata ma mafiafia. O le fa'asologa o le hydroxypropylcellulose e aofia ai le tele o laasaga ma o le faagasologa e mafai ona faigata.

Folasaga ile hydroxypropylcellulose:

1. Fa'aaogaina o le cellulose e fai ma mea amata:

O fa'apogai autu o le cellulose o mea fa'ato'aga e pei o le pulu laupapa po'o le cotton. O le Cellulose o se polymer laina e fausia i iunite kulukose e fesoʻotaʻi i fusi β-1,4-glycosidic. E maualuga lona tulaga o le polymerization, ma le faitau afe o iunite kulukose e fausia ai filifili uumi.

2. Etherification tali:

O le tu'ufa'atasiga o le hydroxypropylcellulose e aofia ai le fa'aofiina o vaega hydroxypropyl i totonu o le cellulose backbone e ala i le etherification. Ole tali lea e masani ona aofia ai le fa'aogaina ole propylene oxide e fai ma sui ole alkylating.

Cellulose + propylene oxide → alkali-catalyzed hydroxypropyl cellulose + cellulose e maua mai i oloa + propylene oxide alkali-catalyzed hydroxypropyl cellulose + oloa gaosi

E mana'omia le fa'avasegaina e fa'alauiloa ai le tali i le va o vaega o le cellulose hydroxyl ma le propylene oxide. O lenei laasaga e masani lava ona faia i lalo o tulaga faʻatonutonu e faʻamautinoa ai le tulaga manaʻomia o le suitulaga (DS) o vaega hydroxypropyl i luga o le filifili cellulose.

3. Hydroxypropylation:

Hydroxypropylation e aofia ai le faʻaopoopoina o vaega hydroxypropyl i le cellulose tua. O lenei suiga e maua ai le faʻaleleia atili o le solubility ma isi mea manaʻomia ile cellulosic polymer. Tulaga tali, e aofia ai le vevela, mamafa ma le taimi e tali atu ai, e pulea lelei ina ia ausia mea e manaʻomia.

4. Togafitiga alkali:

A maeʻa le hydroxypropylation, e masani ona faʻaaogaina togafitiga alkaline e faʻafefe ai soʻo se mea leaga o loʻo totoe ma fetuunai le pH o le faʻafefiloi o tali. O lenei laasaga e taua tele mo le faagasologa o le faamamaina mulimuli ane.

5. Laasaga fa'amamāina:

A maeʻa le etherification reaction, e tele ni laasaga faʻamamaina e masani ona faia e maua ai le hydroxypropylcellulose maualuga-mama. O laasaga nei e mafai ona aofia ai:

Fufulu: Fufulu le paluga fa'afoliga e aveese ai mea fa'ato'aga o lo'o totoe, oloa fa'atasi ma selulose e le'i gaoioi.

Filtration: E fa'aogaina le fa'amama e tu'u'ese'ese ai mea leaga malō mai le fa'afefiloi fa'afoliga.

Fa'agogo: E fa'amago le susū hydroxypropyl cellulose e aveese ai so'o se susū o totoe.

6. Pulea mamafa mole:

O le mamafa mole mole o le hydroxypropylcellulose e mafai ona pulea i le taimi o le tuʻufaʻatasiga e faʻafetaui ai ana meatotino i faʻaoga patino. E maua lenei mea e ala i le fetuutuunai o tulaga tali, e pei o le aofaʻi o reagents ma le taimi faʻaalia.

gaosiga fa'apisinisi:

1. Fa'agasologa fa'asolosolo pe fa'aauau:

O le gaosiga o le hydroxypropyl cellulose e mafai ona faʻatinoina i le faʻasologa poʻo le faʻaauau pea. O le faʻagasologa o le faʻagasologa e talafeagai mo le gaosiga o laʻititi, ae o le faʻaauau pea o le faʻagasologa e sili atu ona talafeagai mo le gaosiga tele.

2. Pulea lelei:

O faʻatonuga lelei e faʻatinoina i laʻasaga uma o le gaosiga o gaosiga e faʻamautinoa ai le tumau ma le mama o le oloa mulimuli. O metotia su'esu'e e pei o le chromatography, spectroscopy ma su'esu'ega rheological e fa'aaogaina e iloilo ai vaega taua e pei o le tikeri o le sui, mamafa mole ma le mama.

Fa'aaogāga ole Hydroxypropyl Cellulose:

1. Alamanuia tau vailaau:

O le Hydroxypropylcellulose e masani ona faʻaaogaina i vailaʻau vailaʻau e avea o se mea e fusifusia ai, faʻaleagaina ma faʻatonuina le faʻamalolo. O lona fetaui lelei ma le tele o vaila'au ma lona inertness ua avea ai ma mea fa'apitoa e fesoasoani ai.

2. Alamanuia mea teuteu:

I totonu o pisinisi teuteu, hydroxypropylcellulose o loʻo faʻaaogaina i le faʻatulagaina o oloa tausiga o lauulu, kulimi paʻu ma isi mea tau tausiga a le tagata lava ia. O ana mea e fai ata tifaga e fa'atauaina ai i mea e teu ai lauulu.

3. Alamanuia tau taumafa:

I totonu o pisinisi taumafa, o le hydroxypropylcellulose o loʻo faʻaaogaina e avea o se mafiafia ma gelling agent. E maua i mea'ai 'ese'ese ma fesoasoani e fa'aleleia atili le tino ma le mautu.

O le faʻapipiʻiina o le hydroxypropylcellulose e aofia ai le etherification o le cellulose e ala i le faʻaopoopoga o vaega hydroxypropyl. O le tali e masani lava ona faʻapipiʻiina e se faʻavae, sosoo ai ma laasaga faʻamamaina e maua ai se oloa sili ona mama. O gaosiga fa'apisinisi e mafai ona fa'atinoina e ala i fa'aputuga po'o fa'aauau faiga fa'atasi ai ma faiga fa'atonutonu lelei. Hydroxypropylcellulose o loʻo i ai le tele o faʻaoga i totonu o falemaʻi, vailaʻau ma meaʻai ona o ona uiga faʻapitoa ma agavaʻa. O le faʻaauauina pea o le faʻaleleia o faiga gaosiga ma le atinaʻeina o talosaga fou e faʻamamafa ai le


Taimi meli: Tes-26-2023
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