Focus on Cellulose ethers

Kutsimikiza kwa Zomwe zili m'malo mu Non-ionic Cellulose Ether ndi Gas Chromatography

Non-ionic Cellulose Ether ndi Gas Chromatography

Zomwe zili m'malo mwa non-ionic cellulose ether zinatsimikiziridwa ndi chromatography ya gas, ndipo zotsatira zake zinafaniziridwa ndi titration ya mankhwala potengera nthawi, ntchito, kulondola, kubwereza, mtengo, ndi zina zotero, ndipo kutentha kwa mzati kunakambidwa. Chikoka cha chromatographic mikhalidwe monga kutalika ndime pa kulekana. Zotsatira zikuwonetsa kuti gasi chromatography ndi njira yowunikira yomwe iyenera kutchuka.
Mawu ofunika: non-ionic cellulose ether; chromatography ya gasi; zolowa m'malo

Nonionic cellulose ethers monga methylcellulose (MC), hydroxypropylmethylcellulose (HPMC), hydroxyethylcellulose (HEC), etc. Zinthuzi zimagwiritsidwa ntchito kwambiri mu mankhwala, chakudya, mafuta a petroleum, ndi zina zotero. ionic mapadi efa zipangizo, m`pofunika kudziwa zili m`malo molondola komanso mwamsanga. Pakadali pano, opanga ambiri apakhomo amatengera njira yachikhalidwe yowerengera mankhwala kuti aunike, yomwe imakhala yogwira ntchito kwambiri komanso yovuta kutsimikizira kulondola komanso kubwereza. Pachifukwa ichi, pepala ili likuphunzira njira yodziwira zomwe zili m'malo mwa ma cellulose ether omwe si a ionic ndi chromatography ya gas, amasanthula zinthu zomwe zimakhudza zotsatira za mayeso, ndikupeza zotsatira zabwino.

1. Yesani
1.1 Chida
GC-7800 gas chromatograph, yopangidwa ndi Beijing Purui Analytical Instrument Co., Ltd.
1.2 Reagents
Hydroxypropyl methylcellulose (HPMC), hydroxyethylcellulose (HEC), zopanga tokha; methyl iodide, ethyl iodide, isopropane iodide, hydroiodic acid (57%), toluene, adipic acid, o-di Toluene anali wa analytical grade.
1.3 Kutsimikiza kwa chromatography ya gasi
1.3.1 Mikhalidwe ya chromatography ya gasi
Chitsulo chosapanga dzimbiri (SE-30, 3% Chmmosorb, WAW DMCS); kutentha kwa chipinda cha vaporization 200 ° C; chowunikira: TCD, 200 ° C; kutentha kwapakati 100 ° C; mpweya wonyamula: H2, 40 mL / min.
1.3.2 Kukonzekera njira yothetsera
(1) Kukonzekera njira yothetsera mkati: Tengani pafupifupi 6.25g ya toluene ndikuyika mu botolo la volumetric 250mL, tsitsani chizindikirocho ndi o-xylene, gwedezani bwino ndikuyika pambali.
(2) Kukonzekera yankho lokhazikika: zitsanzo zosiyanasiyana zimakhala ndi mayankho ofanana, ndipo zitsanzo za HPMC zimatengedwa ngati chitsanzo apa. Mu vial yoyenera, onjezerani kuchuluka kwa asidi adipic, 2 mL wa hydroiodic acid ndi yankho lamkati lamkati, ndikuyeza bwino vial. Onjezani mulingo woyenera wa iodoisopropane, yesani, ndikuwerengera kuchuluka kwa iodoisopropane yomwe yawonjezeredwa. Onjezani methyl iodide kachiwiri, yesani mofanana, werengerani kuchuluka komwe kumawonjezera methyl iodide. Kunjenjemera kwathunthu, lolani kuti iziyimire ngati stratification, ndikuyiyika kutali ndi kuwala kuti igwiritsidwe ntchito mtsogolo.
1.3.3 Kukonzekera chitsanzo cha yankho
Kulemera molondola 0.065 g youma HPMC chitsanzo mu 5 mL wandiweyani-mipanda riyakitala, kuwonjezera kulemera ofanana adipic asidi, 2 mL wa mkati muyezo njira ndi asidi hydroiodic, mwamsanga kusindikiza anachita botolo, ndi molondola kulemera. Gwirani ndi kutentha kwa 150 ° C kwa mphindi 60, ndikugwedezani bwino panthawiyi. Kuzizira ndi kulemera. Ngati kuwonda kusanachitike komanso pambuyo pakuchitako kuli kwakukulu kuposa 10 mg, yankho lachitsanzo ndilosavomerezeka ndipo yankho liyenera kukonzedwanso. Njira yachitsanzo itatha kuloledwa kuyimira stratification, jambulani mosamala 2 μL ya yankho lapamwamba la organic gawo, jekeseni mu chromatograph ya mpweya, ndikulemba mawonekedwewo. Zitsanzo zina zopanda ionic cellulose ether zinachitidwa mofanana ndi HPMC.
1.3.4 Mfundo yoyezera
Kutengera chitsanzo cha HPMC, ndi cellulose alkyl hydroxyalkyl etha yosakanikirana, yomwe imatenthedwa ndi asidi ya hydroiodic kuti ithyole zomangira zonse za methoxyl ndi hydroxypropoxyl ether ndikupanga iodoalkane yofananira.
Pansi pa kutentha kwambiri komanso mpweya wabwino, ndi adipic acid monga chothandizira, HPMC imakhudzidwa ndi hydroiodic acid, ndipo methoxyl ndi hydroxypropoxyl amasinthidwa kukhala methyl iodide ndi isopropane iodide. Kugwiritsa ntchito o-xylene monga chosungunulira ndi zosungunulira, ntchito ya chothandizira ndi choyamwitsa ndikulimbikitsa kuyankha kwathunthu kwa hydrolysis. Toluene amasankhidwa ngati njira yothetsera mkati, ndipo methyl iodide ndi isopropane iodide amagwiritsidwa ntchito ngati yankho lokhazikika. Malinga ndi madera apamwamba a muyezo wamkati ndi yankho lokhazikika, zomwe zili mu methoxyl ndi hydroxypropoxyl mu zitsanzo zitha kuwerengedwa.

2. Zotsatira ndi zokambirana
Mzere wa chromatographic womwe wagwiritsidwa ntchito poyesa uku si polar. Malinga ndi kuwira kwa gawo lililonse, dongosolo lapamwamba ndi methyl iodide, isopropane iodide, toluene ndi o-xylene.
2.1 Kuyerekeza pakati pa chromatography ya gas ndi titration yamankhwala
Kutsimikiza kwa methoxyl ndi hydroxypropoxyl zomwe zili mu HPMC ndi titration yamankhwala ndizokhwima, ndipo pakali pano pali njira ziwiri zomwe zimagwiritsidwa ntchito nthawi zambiri: njira ya Pharmacopoeia ndi njira yabwino. Komabe, njira ziwiri zonsezi za mankhwala zimafuna kukonzekera njira zambiri zothetsera mavuto, ntchitoyo ndi yovuta, imatenga nthawi, ndipo imakhudzidwa kwambiri ndi zinthu zakunja. Kunena zoona, chromatography ya gasi ndiyosavuta, yosavuta kuphunzira komanso kumvetsetsa.
Zotsatira za methoxyl content (w1) ndi hydroxypropoxyl content (w2) mu HPMC zinatsimikiziridwa ndi gas chromatography ndi chemical titration motsatira. Zitha kuwoneka kuti zotsatira za njira ziwirizi zili pafupi kwambiri, zomwe zimasonyeza kuti njira zonsezi zikhoza kutsimikizira kuti zotsatira zake ndi zolondola.
Poyerekeza ma chemical titration ndi chromatography ya gasi pakugwiritsa ntchito nthawi, kugwiritsa ntchito mosavuta, kubwereza komanso mtengo wake, zotsatira zake zikuwonetsa kuti phindu lalikulu la gawo la chromatography ndilosavuta, mwachangu komanso mwachangu. Palibe chifukwa chokonzekera kuchuluka kwa ma reagents ndi mayankho, ndipo zimangotenga mphindi zoposa khumi kuti muyese chitsanzo, ndipo nthawi yeniyeni yopulumutsidwa idzakhala yaikulu kuposa ziwerengero. Mu njira ya chemical titration, cholakwika cha munthu poweruza pomaliza pake ndi chachikulu, pomwe zotsatira za mayeso a gas chromatography sizikhudzidwa kwambiri ndi zinthu zaumunthu. Kuphatikiza apo, chromatography ya gasi ndi njira yolekanitsa yomwe imalekanitsa zomwe zimachitika ndikuziwerengera. Ngati ingagwirizane ndi zida zina zoyezera, monga GC/MS, GC/FTIR, ndi zina zotero, zitha kugwiritsidwa ntchito kuzindikira zitsanzo zina zovuta zosadziwika (zosinthidwa ulusi) Plain ether products) ndizopindulitsa kwambiri, zomwe sizingafanane ndi titration yamankhwala. . Kuphatikiza apo, zotsatira za chromatography ya gasi ndizabwinoko kuposa za titration yamankhwala.
Kuipa kwa chromatography ya gasi ndikuti mtengo wake ndi wokwera. Mtengo kuyambira pakukhazikitsidwa kwa siteshoni ya chromatography ya gasi mpaka kukonza chida komanso kusankha gawo la chromatographic ndi wokwera kuposa njira yowerengera ma chemical. Kusintha kwa zida ndi miyeso yosiyanasiyana kukhudzanso zotsatira, monga mtundu wa Detector, chromatographic column ndi kusankha kwa stationary, etc.
2.2 Chikoka cha gasi chromatography pazotsatira zotsimikiza
Pazoyeserera za gasi chromatography, chinsinsi ndikuzindikira mikhalidwe yoyenera ya chromatographic kuti mupeze zotsatira zolondola kwambiri. Pakuyesa uku, hydroxyethylcellulose (HEC) ndi hydroxypropylmethylcellulose (HPMC) adagwiritsidwa ntchito ngati zopangira, ndipo chikoka cha zinthu ziwiri, kutentha kwa mzati ndi kutalika kwa mzere, zidaphunziridwa.
Pamene mlingo wa kulekana R ≥ 1.5, amatchedwa kulekana kwathunthu. Malinga ndi zomwe "Chinese Pharmacopoeia", R iyenera kukhala yayikulu kuposa 1.5. Kuphatikizidwa ndi kutentha kwa mzati pa kutentha kutatu, kusintha kwa chigawo chilichonse ndi chachikulu kuposa 1.5, chomwe chimakwaniritsa zofunikira zolekanitsa, zomwe ndi R90°C>R100°C>R110°C. Poganizira za nsonga, chinthu r> 1 ndiye nsonga yamchira, r<1 ndiye nsonga yakutsogolo, ndipo kuyandikira kwambiri ndi 1, kumapangitsanso magwiridwe antchito a chromatographic. Kwa toluene ndi ethyl iodide, R90°C>R100°C>R110°C; o-xylene ndiye chosungunulira chomwe chimakhala ndi malo otentha kwambiri, R90°C
Chikoka cha kutalika kwa gawo pazotsatira zoyeserera chikuwonetsa kuti pamikhalidwe yomweyi, kutalika kokha kwa gawo la chromatographic kumasinthidwa. Poyerekeza ndi ndime yodzaza ya 3m ndi 2m, zotsatira zowunikira ndikusintha kwa gawo la 3m ndizabwinoko, ndipo gawo lalitali limakhala logwira ntchito bwino. Kukwera mtengo, zotsatira zake zimakhala zodalirika.

3. Mapeto
Asidi Hydroiodic ntchito kuwononga etha chomangira sanali ionic mapadi efa kupanga molekyulu yaing'ono ayodini, amene amalekanitsidwa ndi mpweya chromatography ndi quantified ndi mkati muyezo njira kupeza zili m'malo. Kuphatikiza pa hydroxypropyl methylcellulose, ma cellulose ethers oyenera njirayi ndi monga hydroxyethyl cellulose, hydroxyethyl methyl cellulose, ndi methyl cellulose, ndipo njira yochizira yachitsanzo ndi yofanana.
Poyerekeza ndi njira yachikhalidwe yowerengera mankhwala, kusanthula kwa gasi chromatography ya zomwe zili m'malo mwa non-ionic cellulose ether kuli ndi zabwino zambiri. Mfundoyi ndi yosavuta komanso yosavuta kumvetsa, ntchitoyo ndi yabwino, ndipo palibe chifukwa chokonzekera mankhwala ambiri ndi ma reagents, omwe amapulumutsa kwambiri nthawi yowunika. Zotsatira zomwe zimapezedwa ndi njirayi zimagwirizana ndi zomwe zimapezedwa ndi mankhwala a titration.
Mukasanthula zomwe zili m'malo mwa gasi chromatography, ndikofunikira kwambiri kusankha mikhalidwe yoyenera komanso yoyenera. Nthawi zambiri, kuchepetsa kutentha kwa gawo kapena kuwonjezera kutalika kwa gawo kumatha kuwongolera bwino chigamulocho, koma kusamala kuyenera kuchitidwa kuti zigawo zisasunthike pamzati chifukwa cha kutentha kotsika kwambiri.
Pakali pano, ambiri opanga zoweta akugwiritsabe ntchito mankhwala titration kudziwa zili m'malo. Komabe, poganizira zaubwino ndi kuipa kwazinthu zosiyanasiyana, chromatography ya gasi ndi njira yosavuta komanso yachangu yoyesera yomwe ikuyenera kukwezedwa malinga ndi momwe chitukuko chikuyendera.


Nthawi yotumiza: Feb-15-2023
Macheza a WhatsApp Paintaneti!