Yiziphi izakhiwo zamakhemikhali ze-ethyl cellulose?

I-Ethylcellulose iphuma ku-cellulose, i-polymer yemvelo eyakhiwe amayunithi e-glucose.Ihlanganiswa ngokuphendula i-cellulose nge-ethyl chloride noma i-ethylene oxide, ikhiqize ama-molecule e-cellulose ashintshwe kancane.I-Ethylcellulose inezinhlobonhlobo zezakhiwo zamakhemikhali eziyenza ibe wusizo ezinhlotsheni ezihlukene zezimboni nezamakhemisi.

Isakhiwo samangqamuzana:

I-Ethylcellulose igcina isakhiwo esiyisisekelo se-cellulose, esihlanganisa ukuphindaphinda amayunithi e-glucose axhunywe ndawonye ngamabhondi e-β-1,4-glycosidic.

Ukushintshwa kwe-Ethyl kwenzeka ngokuyinhloko emaqenjini e-hydroxyl omgogodla we-cellulose, okuholela kumadigri ahlukene okushintsha (DS) okubonisa inani elimaphakathi lamaqembu e-ethyl ngeyunithi ngayinye ye-glucose.

Izinga lokushintsha lithinta izakhiwo ze-ethylcellulose, okuhlanganisa ukuncibilika, i-viscosity, nekhono lokwenza ifilimu.

Ukunyibilika:

Ngenxa yemvelo ye-hydrophobic yeqembu le-ethyl, i-ethylcellulose ayincibiliki emanzini.

Ibonisa ukuncibilika ezinhlobonhlobo zezinyibilikisi eziphilayo, okuhlanganisa utshwala, ama-ketone, ama-ester, nama-hydrocarbon ane-chlorine.

Ukuncibilika kuyanda ngokuncipha kwesisindo samangqamuzana kanye nezinga elikhulayo le-ethoxylation.

Izakhiwo zokwakha ifilimu:

I-Ethylcellulose yaziwa ngamakhono ayo okwenza ifilimu, iyenze ibe yigugu ekukhiqizweni kwezimbotshana, amafilimu, kanye nokwakhiwa kwemithi ekhishwa okulawulwayo.

Ikhono le-ethylcellulose lokuncibilika ezinhlobonhlobo ze-solvents eziphilayo likhuthaza ukwakheka kwefilimu, nokuhwamuka okulandelayo kwe-solvent kushiya ifilimu efanayo.

Ukusebenza kabusha:

I-Ethylcellulose ikhombisa ukusebenza kabusha okuphansi kakhulu ngaphansi kwezimo ezijwayelekile.Kodwa-ke, ingashintshwa ngokwekhemikhali ngokusabela okufana ne-etherification, i-esterification, nokuxhumanisa.

Ukusabela kwe-etherification kuhilela ukwethulwa kwezinye izinto ezengeziwe kumgogodla we-cellulose, ngaleyo ndlela kuguqule izakhiwo.

I-Esterification ingenzeka ngokusabela i-ethylcellulose ne-carboxylic acid noma i-asidi chloride, ikhiqize ama-cellulose ester ngokuncibilika okushintshile nezinye izici.

Ukusabela kokuxhumanisa kungaqalwa ukuze kuthuthukiswe amandla emishini nokuzinza kokushisa kwe-ethyl cellulose membranes.

Ukusebenza kokushisa:

I-Ethylcellulose ibonisa ukuzinza kokushisa ngaphakathi kwebanga elithile lokushisa, okungaphezu kwalokho ukubola kwenzeka.

Ukuwohloka kokushisa kuvame ukuqala cishe ku-200-250°C, kuya ngezici ezifana nezinga lokushintsha kanye nokuba khona kwamapulasitiki noma izithasiselo.

Ukuhlaziywa kwe-Thermogravimetric (TGA) kanye ne-different scanning calorimetry (DSC) amasu avame ukusetshenziswa ukukhombisa ukuziphatha okushisayo kwe-ethylcellulose kanye nenhlanganisela yayo.

ukuhambisana:

I-Ethylcellulose ihambisana nezinhlobonhlobo zamanye ama-polymers, ama-plasticizers kanye nezithasiselo, okwenza ifaneleke ukuxubana nezinye izinto ukuze kuzuzwe izakhiwo ezifiselekayo.

Izithasiselo ezivamile zihlanganisa ama-plasticizers afana ne-polyethylene glycol (PEG) ne-triethyl citrate, ethuthukisa ukuguquguquka kanye nezakhiwo zefilimu.

Ukuhambisana nezithako ezisebenzayo zemithi (ama-API) kubalulekile ekwakhiweni kwamafomu omthamo wemithi njengamaphilisi okukhishwa okunwetshiwe nama-transdermal patches.

Ukusebenza kwesithiyo:

Amafilimu e-Ethylcellulose abonisa izakhiwo ezinhle kakhulu zokuvimbela ngokumelene nomswakama, amagesi kanye nama-organic vapors.

Lezi zakhiwo zokuvimbela zenza i-ethylcellulose ifanelekele izinhlelo zokusebenza zokupakisha lapho ukuvikelwa ezintweni zemvelo kubalulekile ekugcineni ubuqotho bomkhiqizo nempilo yeshalofu.

Izici ze-Rheological:

I-viscosity yezixazululo ze-ethylcellulose incike ezintweni ezifana nokugxila kwe-polymer, izinga lokushintshwa, kanye nohlobo lwe-solvent.

Izixazululo ze-Ethylcellulose zivame ukubonisa ukuziphatha kwe-pseudoplastic, okusho ukuthi i-viscosity yazo iyancipha ngokunyuka kwesilinganiso sokugunda.

Izifundo ze-Rheological zibalulekile ukuqonda izici zokugeleza kwezixazululo ze-ethylcellulose ngesikhathi sokucubungula nokufaka izicelo.

I-Ethylcellulose iyi-polymer eguquguqukayo enezinhlobonhlobo zezakhiwo zamakhemikhali ezinomthelela ekusebenziseni kwayo ezinhlotsheni ezihlukene zezimboni nezamakhemisi.I-solubility yayo, ikhono lokwenza ifilimu, ukuvuselela kabusha, ukuzinza okushisayo, ukuhambisana, izakhiwo zokuvimbela kanye ne-rheology kwenza kube yinto ebalulekile yokugqoka, amafilimu, ukwakheka kokukhululwa okulawulwayo kanye nezixazululo zokupakisha.Ucwaningo olwengeziwe kanye nentuthuko emkhakheni we-cellulose derivatives iyaqhubeka nokwandisa ukusetshenziswa kanye namandla e-ethylcellulose emikhakheni ehlukahlukene.