Umthelela wedigri ye-substitution (DS) kukhwalithi ye-HEC

I-HEC (i-hydroxyethyl cellulose) iyi-polymer engeyona i-ionic, encibilika emanzini esetshenziswa kakhulu ezimbonini ezahlukahlukene ezinjengokunakekelwa komuntu siqu, ezemithi, nokudla njenge-ejenti ejiyayo, ebophayo, neqinisayo. I-degree of substitution (DS) iyipharamitha ebalulekile engathinta kakhulu izakhiwo nokusebenza kwe-HEC.

Izinga lokushintsha lisho inombolo emaphakathi yamaqembu e-hydroxyethyl anamathiselwe kuyunithi ngayinye ye-anhydroglucose yomgogodla we-cellulose. Ngamanye amazwi, ikala izinga lapho i-molecule ye-cellulose ishintshwe ngayo ngamaqembu e-hydroxyethyl.

Umthelela wezinga lokushintsha kukhwalithi ye-HEC ubalulekile. Ngokuvamile, njengoba izinga lokushintsha likhula, ukuncibilika kwe-HEC emanzini kuyanda, futhi i-viscosity yayo iyancipha. I-HEC enezinga eliphakeme lokushintsha ine-viscosity ephansi, futhi inyibilika kakhulu emanzini. Lokhu kungenxa yokuthi amaqembu e-hydroxyethyl aphazamisa ukuhlangana kwe-hydrogen phakathi kwamaketanga e-cellulose, okuholela esakhiweni esivuleke kakhudlwana futhi esivumelana nezimo.

Ngaphezu kwalokho, izinga eliphakeme lokufaka esikhundleni lingathuthukisa ukuzinza kokushisa kwe-HEC futhi kwandise ukumelana kwayo nokuwohloka kwe-enzymatic. Kodwa-ke, izinga eliphezulu kakhulu lokufaka esikhundleni lingaholela ekunciphiseni kwesisindo samangqamuzana nokulahlekelwa izakhiwo zangempela ze-cellulose backbone, ezingathinta ukusebenza okuphelele kwe-HEC.

Kafushane, izinga lokushintsha liyipharamitha ebalulekile engathinta kakhulu izakhiwo nokusebenza kwe-HEC. Izinga eliphakeme lokufaka esikhundleni lingathuthukisa ukuncibilika nokuzinza kokushisa kwe-HEC, kodwa izinga eliphezulu kakhulu lokufaka esikhundleni lingaholela ekulahlekelweni kwezakhiwo zangempela ze-cellulose backbone, ezingathinta ukusebenza okuphelele kwe-HEC.