Ziziphi iimpawu zeekhemikhali ze-ethyl cellulose?

I-Ethylcellulose iphuma kwi-cellulose, i-polymer yendalo eyenziwe ngeeyunithi ze-glucose.Idityaniswe ngokuphendula i-cellulose nge-ethyl chloride okanye i-ethylene oxide, ivelisa iimolekyuli ze-cellulose ezithatha indawo.I-Ethylcellulose inoluhlu lweempawu zeekhemikhali ezenza ukuba zibe luncedo kwiindidi ezahlukeneyo zoshishino kunye nokusetyenziswa kwamachiza.

Ulwakhiwo lweMolekyuli:

I-Ethylcellulose igcina isakhiwo esisisiseko se-cellulose, equlethwe ngokuphindaphindiweyo kweeyunithi ze-glucose ezidityaniswe kunye ne-β-1,4-glycosidic bonds.

Ukutshintshwa kwe-Ethyl kwenzeka ngokuyinhloko kumaqela e-hydroxyl ye-cellulose backbone, okukhokelela kwiidigri ezahlukeneyo zokutshintshwa (DS) ezibonisa inani eliqhelekileyo lamaqela e-ethyl kwiyunithi ye-glucose.

Iqondo lokutshintshwa lichaphazela iipropati ze-ethylcellulose, kubandakanywa ukunyibilika, i-viscosity, kunye nokukwazi ukwenza ifilimu.

Ukunyibilika:

Ngenxa yobume be-hydrophobic yeqela le-ethyl, i-ethylcellulose ayinyibiliki emanzini.

Ibonisa ukunyibilika kwiintlobo ezahlukeneyo ze-solvents eziphilayo, kuquka i-alcohols, i-ketones, i-esters, kunye ne-hydrocarbons e-chlorinated.

Ukunyibilika kuyanda ngokuncipha kobunzima bemolekyuli kunye nokwanda kweqondo le-ethoxylation.

Iimpawu zokwenza ifilimu:

I-Ethylcellulose iyaziwa ngokuba namandla okwenza ifilimu, okwenza ukuba ixabiseke kwimveliso yeengubo, iifilimu, kunye nokulawulwa kokukhutshwa kwamayeza.

Ikhono le-ethylcellulose ukunyibilika kwiintlobo ezahlukeneyo ze-solvents eziphilayo zikhuthaza ukubunjwa kwefilimu, kunye nokunyuka kwe-evaporation okulandelayo kwe-solvent kushiya ifilimu efanayo.

Ukuphinda kusebenze:

I-Ethylcellulose ibonisa ukuphinda kusebenze okuphantsi phantsi kweemeko eziqhelekileyo.Nangona kunjalo, inokuguqulwa ngokwekhemikhali ngokusabela okunje nge-etherification, i-esterification, kunye nokudibanisa.

Iimpendulo ze-Etherification zibandakanya ukuqaliswa kwezinto ezongezelelweyo kwi-cellulose backbone, ngaloo ndlela kutshintsha iipropati.

I-Esterification ingenzeka ngokuphendula i-ethylcellulose kunye ne-carboxylic acids okanye i-acid chlorides, ukuvelisa i-cellulose esters kunye ne-solubility etshintshileyo kunye nezinye iimpawu.

Iimpendulo ze-Cross-linking zingaqaliswa ukuphucula amandla omatshini kunye nokuzinza kwe-thermal ye-ethyl cellulose membranes.

Ukusebenza kobushushu:

I-Ethylcellulose ibonisa ukuzinza kwe-thermal ngaphakathi kwinqanaba elithile lobushushu, ngaphaya kokubola kwenzeka.

Ukuthotywa kwe-thermal ngokuqhelekileyo kuqala malunga ne-200-250 ° C, kuxhomekeke kwizinto ezifana neqondo lokutshintshwa kunye nobukho beplastiki okanye izongezo.

Uhlalutyo lwe-Thermogravimetric (TGA) kunye ne-different scanning calorimetry (DSC) zisetyenziswa ngokuqhelekileyo iindlela zokubonisa ukuziphatha kwe-thermal ye-ethylcellulose kunye nemixube yayo.

ukuhambelana:

I-Ethylcellulose iyahambelana nezinye iindidi ze-polymers, i-plasticizers kunye ne-additives, okwenza ukuba ilungele ukudibanisa kunye nezinye izinto ezifunekayo ukuphumeza iipropati ezifunwayo.

Izongezo eziqhelekileyo ziquka iiplastiki ezifana ne-polyethylene glycol (PEG) kunye ne-triethyl citrate, ephucula ukuguquguquka kunye neepropati zokwenza ifilimu.

Ukuhambelana nezithako ezisebenzayo zamachiza (APIs) zibaluleke kakhulu ekuqulunqweni kweefom ze-dosage ye-pharmaceutical dosage ezifana neepilisi zokukhululwa okwandisiweyo kunye neepatches ze-transdermal.

Ukusebenza komqobo:

Iifilimu ze-Ethylcellulose zibonisa iimpawu ezintle zokuthintela ngokuchasene nokufuma, iigesi kunye nomphunga we-organic.

Ezi zakhiwo zomqobo zenza i-ethylcellulose ilungele ukupakishwa kwezicelo apho ukukhuselwa kwizinto ezisingqongileyo kubalulekile ekugcineni ukuthembeka kwemveliso kunye nobomi beshelufu.

Iimpawu zeRheological:

I-viscosity yezisombululo ze-ethylcellulose ixhomekeke kwizinto ezifana nokugxininiswa kwe-polymer, i-degree of substitution, kunye nohlobo lwe-solvent.

Izisombululo ze-Ethylcellulose zihlala zibonisa ukuziphatha kwe-pseudoplastic, oku kuthetha ukuba i-viscosity yabo iyancipha ngokunyuka kwesantya sokucheba.

Izifundo ze-Rheological zibalulekile ukuqonda iimpawu ezihambayo zezisombululo ze-ethylcellulose ngexesha lokucubungula kunye nokufakwa kwezicelo.

I-Ethylcellulose i-polymer eguquguqukayo kunye noluhlu lweepropathi zekhemikhali ezifaka isandla ekusebenziseni kwayo kwiintlobo ezahlukeneyo zoshishino kunye nokusetyenziswa kwamachiza.Ukunyibilika kwayo, ukukwazi ukwenza ifilimu, ukuphinda kusebenze, ukuzinza kwe-thermal, ukuhambelana, iipropathi zomqobo kunye ne-rheology yenza kube yinto exabisekileyo yokugubungela, iifilimu, iifomyula ezilawulwayo zokukhululwa kunye nezisombululo zokupakisha.Uphando olongezelelweyo kunye nophuhliso kwintsimi ye-cellulose derivatives iyaqhubeka nokwandisa izicelo kunye namandla e-ethylcellulose kwiinkalo ezahlukeneyo.