IHydroxypropyl methylcellulose (HPMC) yi-semi-synthetic, i-polymer enyibilikayo emanzini ephuma kwi-cellulose.Isetyenziswa kakhulu kumashishini ahlukeneyo, kubandakanya amayeza, ukutya, ulwakhiwo, kunye nezinto zokuthambisa, ngenxa yeempawu zayo ezizodwa ezinjengokuqina, ukubopha, ukwenza ifilimu, kunye nokuzinzisa.Nangona kunjalo, kubalulekile ukuqaphela ukuba i-HPMC ayinayo indawo yokunyibilika ethile kuba ayihambi kwinkqubo yokwenyani yokunyibilika njengezixhobo zekristale.Endaweni yoko, ifumana inkqubo yokuthotywa kwe-thermal xa ishushu.
1. Iipropati ze-HPMC:
I-HPMC yimpuphu emhlophe ukuya emhlophe engenavumba, enyibilikayo emanzini kunye nezinyibilikisi ezininzi eziphilayo.Iimpawu zayo ziyahluka ngokuxhomekeke kwizinto ezifana neqondo lokutshintshela (DS), ubunzima bemolekyuli, kunye nokusabalalisa ubungakanani besuntswana.Ngokubanzi, ibonisa ezi mpawu zilandelayo:
Ubume be-non-ionic: I-HPMC ayithwali nayiphi na intlawulo yombane kwisisombululo, iyenza ihambelane noluhlu olubanzi lwezinye izinto.
Ukwenziwa kwefilimu: I-HPMC inokwenza iifilimu ezicacileyo, eziguquguqukayo xa zomile, ezifumana izicelo kwiingubo, iifilimu, kunye neefom zedosi ezilawulwayo kumayeza.
I-ejenti yokutyebisa: Inika i-viscosity kwizisombululo, iyenza ibe luncedo kwiimveliso zokutya, izinto zokuthambisa, kunye namayeza.
I-Hydrophilic: I-HPMC inobudlelwane obuphezulu bamanzi, obunegalelo ekunyibilikeni kwayo kunye neempawu zokwenza ifilimu.
2. Ukwenziwa kwe-HPMC:
I-HPMC idityaniswe ngothotho lweempendulo zemichiza ezibandakanya i-cellulose, ipropylene oxide, kunye ne-methyl chloride.Inkqubo ibandakanya i-etherification ye-cellulose kunye nepropylene oxide elandelwa yi-methylation kunye ne-methyl chloride.Iqondo lokutshintshwa (DS) lwe-hydroxypropyl kunye namaqela e-methoxy anokulawulwa ukuze alungelelanise iimpawu ze-HPMC enesiphumo.
3. Usetyenziso lwe-HPMC:
Umzi-mveliso wamachiza: I-HPMC isetyenziswa ngokubanzi njenge-excipient kwi-formulations yamayeza, kubandakanywa iipilisi, ii-capsules, izisombululo zamehlo, kunye neefom zedosi elawulwayo.
Umzi-mveliso wokutya: Isetyenziswa njenge-thickener, stabilizer, kunye ne-emulsifier kwiimveliso zokutya ezifana neesosi, isuphu, ii-ice creams, kunye nezinto zokubhaka.
Ishishini lokwakha: I-HPMC yongezwa kwiimveliso ezisekwe kwisamente ukuphucula ukusebenza, ukugcinwa kwamanzi, kunye nokuncamathela.Ikwasetyenziselwa ukuncamathelisa iithayile, udaka, kunye nonikezelo.
Umzi-mveliso wezithambiso: I-HPMC isetyenziswa kwiindlela ezahlukeneyo zokuthambisa ezifana neekhrimu, izinto zokuthambisa, kunye neeshampu zokujiya nokuzinzisa iipropati.
4. Ukuziphatha kweThermal ye-HPMC:
Njengoko bekutshiwo ngaphambili, i-HPMC ayinayo indawo yokunyibilika ethile ngenxa yobume bayo be-amorphous.Endaweni yoko, ifumana ukuthotywa kwe-thermal xa ishushu.Inkqubo yokwehlisa umgangatho ibandakanya ukuqhawuka kwamabhondi ekhemikhali ngaphakathi kwekhonkco lepolymer, okukhokelela ekwakhekeni kweemveliso zokubola okuguquguqukayo.
Ukushisa kokuthotywa kwe-HPMC kuxhomekeke kwizinto ezininzi, kuquka ubunzima bayo bemolekyuli, iqondo lokuthatha indawo, kunye nobukho bezongezo.Ngokuqhelekileyo, ukuthotywa kwe-thermal ye-HPMC iqala malunga ne-200 ° C kwaye iqhubela phambili ngokunyuka kweqondo lokushisa.Iprofayili yokuthotywa ingahluka kakhulu ngokuxhomekeke kwibakala elithile le-HPMC kunye nezinga lokufudumeza.
Ngexesha lokuthotywa kwe-thermal, i-HPMC iqhuba iinkqubo ezininzi ezihambelanayo, kubandakanywa ukuchithwa kwamanzi, ukuchithwa kwe-depolymerization, kunye nokubola kwamaqela asebenzayo.Iimveliso eziphambili zokubola ziquka amanzi, i-carbon dioxide, i-carbon monoxide, i-methanol, kunye nee-hydrocarbons ezahlukeneyo.
5. IiTeknikhi zokuHlalutya iThermal kwi-HPMC:
Ukuziphatha okushushu kwe-HPMC kunokufundwa kusetyenziswa iindlela ezahlukeneyo zohlalutyo, kubandakanya:
Uhlalutyo lwe-Thermogravimetric (TGA): I-TGA ilinganisa ukulahleka kwesisindo sesampuli njengomsebenzi weqondo lokushisa, inika ulwazi malunga nokuzinza kwayo kwe-thermal kunye ne-kinetics yokubola.
I-calorimetry yokuskena eyahlukileyo (i-DSC): I-DSC ilinganisa ukuhamba kobushushu ngaphakathi okanye ngaphandle kwesampulu njengomsebenzi weqondo lokushisa, okuvumela ukubonakaliswa kweenguqu zesigaba kunye neziganeko ze-thermal ezifana nokunyibilika kunye nokuthotywa.
I-Fourier-transform infrared spectroscopy (FTIR): I-FTIR ingasetyenziselwa ukujonga utshintsho lweekhemikhali kwi-HPMC ngexesha lokuthotywa kwe-thermal ngokuhlalutya utshintsho kumaqela asebenzayo kunye nesakhiwo se-molecular.
6. Isiphelo:
I-HPMC yipolymer eguquguqukayo enoluhlu olubanzi lwezicelo kumayeza, ukutya, ukwakhiwa, kunye nezithambiso.Ngokungafaniyo nezixhobo zekristale, i-HPMC ayinayo indawo yokunyibilika ethile kodwa ifumana ukuthotywa kwe-thermal xa ishushu.Iqondo lobushushu elithotyiweyo lixhomekeke kwizinto ezahlukeneyo kwaye ngokuqhelekileyo liqala malunga nama-200°C.Ukuqonda ukuziphatha kwe-thermal ye-HPMC kubalulekile kulawulo lwayo olufanelekileyo kunye nokucubungula kumashishini ahlukeneyo.
Ixesha lokuposa: Mar-09-2024