IHydroxypropyl methylcellulose (HPMC) yipolymer eguquguqukayo enoluhlu olubanzi lwezicelo kumashishini ahlukeneyo, kubandakanywa amayeza, ukutya, ukwakhiwa, kunye nezithambiso. Xa kujongwa iipropathi zayo ze-thermal, kubalulekile ukukhangela kwindlela yokuziphatha kwayo malunga nokutshintsha kobushushu, ukuzinza kwe-thermal, kunye nayo nayiphi na into ehambelana nayo.
Ukuzinza kweThermal: I-HPMC ibonisa uzinzo oluhle lwe-thermal kuluhlu olubanzi lobushushu. Ngokuqhelekileyo ibola kumaqondo obushushu aphezulu, ngokuqhelekileyo ngaphezu kwe-200 ° C, kuxhomekeke kubunzima bayo bemolekyuli, iqondo lokutshintshwa, kunye nezinye izinto. Inkqubo yokunciphisa ibandakanya ukuqhekeka kwe-cellulose backbone kunye nokukhululwa kweemveliso zokubola eziguquguqukayo.
Ubushushu beGlass Transition (Tg): Njengeepholima ezininzi, i-HPMC idlula kwinguqu yeglasi ukusuka kwiglasi ukuya kwimeko yerabha enobushushu obukhulayo. I-Tg ye-HPMC iyahluka ngokuxhomekeke kwiqondo lokuthatha indawo, ubunzima bemolekyuli, kunye nomxholo wokufuma. Ngokuqhelekileyo, ukusuka kwi-50 ° C ukuya kwi-190 ° C. Ngaphezulu kwe-Tg, i-HPMC iba bhetyebhetye ngakumbi kwaye ibonisa ukunyuka kokuhamba kweemolekyuli.
Indawo yokunyibilika: I-HPMC esulungekileyo ayinayo indawo yokunyibilika eyahlukileyo kuba iyipolima e-amorphous. Nangona kunjalo, iyathamba kwaye inokuhamba kumaqondo obushushu aphezulu. Ubukho bezongezo okanye ukungcola kunokuchaphazela ukuziphatha kwayo okunyibilikayo.
I-Thermal Conductivity: I-HPMC ine-conductivity ephantsi yobushushu xa kuthelekiswa nesinyithi kunye nezinye iipholima. Le propati yenza ukuba ifaneleke kwizicelo ezifuna i-thermal insulation, njengakwiipilisi zamachiza okanye izinto zokwakha.
Ukwandiswa kweThermal: Njengoninzi lweepolymers, i-HPMC iyakhula xa ishushu kwaye inekhontrakthi xa ipholile. I-coefficient yokwanda kwe-thermal (CTE) ye-HPMC ixhomekeke kwizinto ezifana nokwakheka kweekhemikhali kunye neemeko zokusetyenzwa. Ngokubanzi, ine-CTE kuluhlu lwe-100 ukuya kuma-300 ppm/°C.
Umthamo wobushushu: Umthamo wobushushu we-HPMC uphenjelelwa sisakhiwo sayo semolekyuli, iqondo lokuthatha indawo, kunye nomxholo wokufuma. Ngokuqhelekileyo ukusuka kwi-1.5 ukuya kwi-2.5 J/g°C. Amazinga aphezulu okutshintsha kunye nomxholo wokufuma athande ukwandisa umthamo wobushushu.
Ukuthotywa kweThermal: Xa evezwe kumaqondo obushushu aphezulu ixesha elide, i-HPMC inokwehlelwa kukuthotywa kwe-thermal. Le nkqubo inokubangela utshintsho kwisakhiwo sayo samachiza, okukhokelela ekulahlekelweni kweempawu ezifana ne-viscosity kunye namandla omatshini.
I-Thermal Conductivity Enhancement: I-HPMC inokuguqulwa ukuze ikhulise ukuhanjiswa kwayo kwe-thermal kwizicelo ezithile. Ukubandakanya iifayili okanye izongezo, ezifana neengqungquthela zetsimbi okanye i-carbon nanotubes, zinokuphucula iimpawu zokutshintshwa kobushushu, zenze ukuba zilungele izicelo zolawulo lwe-thermal.
Ukusetyenziswa: Ukuqonda iimpawu ze-thermal ze-HPMC kubalulekile ekwandiseni ukusetyenziswa kwayo kwizicelo ezahlukeneyo. Kwimichiza, isetyenziswa njenge-binder, ifilimu yangaphambili, kunye ne-ejenti yokukhululwa okuqhubekayo kwi-tablet formulations. Ekwakhiweni, isetyenziswa kwizinto ezisekelwe kwisamente ukuphucula ukusebenza, ukunamathela, kunye nokugcinwa kwamanzi. Ekutyeni nakwizinto zokuthambisa, isebenza njenge-thickener, stabilizer, kunye ne-emulsifier.
IHydroxypropyl methylcellulose (HPMC) ibonisa uluhlu lweepropathi ezishushu eziyenza ilungele usetyenziso olwahlukeneyo kuwo onke amashishini. Ukuzinza kwayo kwe-thermal, i-glass transition yeqondo lokushisa, i-thermal conductivity, kunye nezinye iimpawu zidlala indima ebalulekileyo ekunqumeni ukusebenza kwayo kwiindawo ezithile kunye nezicelo. Ukuqonda ezi mpawu kubalulekile kusetyenziso olusebenzayo lwe-HPMC kwiimveliso ezahlukeneyo kunye neenkqubo.
Ixesha lokuposa: May-09-2024