Hydroxypropyl methyl cellulose HPMC ne wani nau'i ne na wadanda ba ionic cellulose gauraye ether, wanda ya bambanta da ionic methyl carboxymethyl cellulose gauraye ether, kuma shi ba ya amsa da nauyi karafa. Saboda daban-daban rabo na methoxyl abun ciki da hydroxypropyl abun ciki a hydroxypropyl methylcellulose da daban-daban viscosities, ya zama iri-iri iri-iri tare da daban-daban kaddarorin, misali, high methoxyl abun ciki da low hydroxypropyl abun ciki Ayyukansa yana kusa da na methyl cellulose, kuma nau'ikan da ke da ƙananan abun ciki na methoxyl da babban abun ciki na hydroxypropyl, aikinsa yana kusa da na hydroxypropyl methylcellulose. Koyaya, a cikin nau'ikan iri daban-daban, kodayake ƙaramin rukunin hydroxypropyl ko ƙaramin rukunin methoxy yana ƙunshe, solubility a cikin abubuwan kaushi na ƙwayoyin cuta ko yanayin flocculation a cikin maganin ruwa ya bambanta sosai.
1. Solubility na hydroxypropyl methylcellulose
① Solubility na hydroxypropyl methyl cellulose a cikin ruwa Hydroxypropyl methyl cellulose shine ainihin methyl cellulose wanda aka gyara ta hanyar propylene oxide (methyl oxypropylene), don haka har yanzu yana da kaddarorin da methyl cellulose. Cellulose yayi kama da rashin narkewar ruwan sanyi da rashin narkewar ruwan zafi. Duk da haka, saboda ƙungiyar hydroxypropyl da aka gyara, yawan zafin jiki na gelation a cikin ruwan zafi ya fi girma fiye da na methyl cellulose. Misali, dankowar maganin ruwa na hydroxypropyl methylcellulose tare da abun ciki na methoxyl 2% DS=0.73 da abun ciki na hydroxypropyl MS=0.46 shine 500mpa?s a 20°C. Zafinsa na gel Zai iya kaiwa kusa da 100 ° C, yayin da methylcellulose a cikin zafin jiki guda yana kusan 55 ° C. Dangane da narkewar sa a cikin ruwa, shi ma an inganta shi sosai. Alal misali, da pulverized hydroxypropyl methylcellulose (granular siffar 0.2 ~ 0.5mm a 20 ° C tare da danko na 4% ruwa bayani har zuwa 2pa?s za a iya amfani da a cikin dakin zafin jiki, shi ne sauƙi mai narkewa a cikin ruwa ba tare da sanyaya.
②A solubility na hydroxypropyl methyl cellulose a Organic kaushi The solubility na hydroxypropyl methyl cellulose a Organic kaushi shi ma ya fi na methyl cellulose, da methyl cellulose bukatar samun wani mataki na methoxyl maye gurbin a Products sama da 2.1, da high-danko hydroxypropyl dauke da methylcellulose. hydroxypropyl MS = 1.5 ~ 1.8 da methoxy DS = 0.2 ~ 1.0, da kuma jimlar maye gurbin sama da 1.8 suna soluble a cikin methanol anhydrous da ethanol mafita matsakaici, thermoplastic da ruwa mai narkewa. Hakanan yana narkewa a cikin chlorinated hydrocarbons kamar dichloromethane da chloroform, kuma a cikin abubuwan kaushi kamar acetone, isopropanol da barasa diacetone. Solubility a cikin kwayoyin kaushi yana da kyau fiye da mai narkewar ruwa.
2. Abubuwan da ke shafar danko na hydroxypropyl methylcellulose
Abubuwan da ke tasiri na hydroxypropyl methyl cellulose viscosity Daidaitaccen ƙaddarar danko na hydroxypropyl methyl cellulose, kamar sauran ethers cellulose, ya dogara ne akan maganin 2% mai ruwa a 20 ° C. Danko na samfurin iri ɗaya yana ƙaruwa tare da haɓaka haɓaka. Don samfuran da ke da nau'ikan nau'ikan kwayoyin halitta daban-daban a taro iri ɗaya, samfuran da ke da ma'aunin ƙwayoyin ƙwayoyin cuta mafi girma suna da ɗanko mafi girma. Alakarsa da zafin jiki yayi kama da na methyl cellulose. Lokacin da zafin jiki ya karu, danko ya fara raguwa, amma lokacin da ya kai wani zafin jiki, danko yana ƙaruwa ba zato ba tsammani kuma gelation yana faruwa. Zazzabi gel na samfuran ƙarancin danko ya fi girma. yana da girma. Ma'anar gel ɗin sa ba wai kawai yana da alaƙa da danko na ether ba, amma har ma da abun da ke ciki na methoxy da hydroxypropyl a cikin ether da jimlar matakin maye gurbin. Dole ne a lura cewa hydroxypropyl methylcellulose shima pseudoplastic ne kuma maganin sa yana da karko a cikin zafin jiki ba tare da wani lahani na danko ba sai dai yiwuwar lalatawar enzymatic.
3. Hydroxypropyl methylcellulose acid da juriya na alkali
Hydroxypropyl methylcellulose acid da juriya na alkali Hydroxypropyl methylcellulose gabaɗaya sun tsaya tsayin daka ga acid da alkali, kuma ba a shafa a cikin kewayon pH 2 ~ 12. Yana iya jure wani adadin haske acid. Irin su formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, da dai sauransu. Duk da haka, mai da hankali acid yana da tasirin rage danko. Alkaki irin su caustic soda, caustic potash da ruwan lemun tsami ba su da wani tasiri a kai, sai dai suna iya kara dankowar maganin, sannan kuma za a yi wani abu na raguwa a hankali a nan gaba.
4. Mixability na hydroxypropyl methylcellulose
Miscibility na Hydroxypropyl Methyl Cellulose Hydroxypropyl methyl cellulose bayani za a iya gauraye da ruwa mai narkewa polymer fili ya zama uniform da m bayani tare da mafi girma danko. Wadannan mahadi na polymer sun hada da polyethylene glycol, polyvinyl acetate, polysiloxane, polymethyl vinyl siloxane, hydroxyethyl cellulose da methyl cellulose. Abubuwan da ake amfani da su na polymer na halitta kamar su ɗanɗano arabic, ɗan waken fari, karaya danko, da dai sauransu suma suna da kyakkyawar haɗuwa tare da maganinta. Hydroxypropyl methylcellulose kuma ana iya haɗa shi da mannitol ko sorbitol esters na stearic acid ko palmitic acid, kuma ana iya haɗa su da glycerin, sorbitol da mannitol. Ana iya amfani da waɗannan mahadi azaman hydroxypropyl methylcellulose. Plasticizer na tushen Cellulose.
5. Rashin ruwa da ruwa na hydroxypropyl methylcellulose
The insolubilized ruwa-soluble cellulose ethers na hydroxypropyl methylcellulose za a iya a saman-crosslinked tare da aldehydes, da kuma wadannan ruwa-soluble ethers suna hazo a cikin bayani da kuma zama insoluble a cikin ruwa. Aldehydes da ke yin hydroxypropyl methylcellulose mai narkewa sun haɗa da formaldehyde, glioxal, succinaldehyde, adipaldehyde, da dai sauransu Lokacin amfani da formaldehyde, ya kamata a biya kulawa ta musamman ga darajar pH na maganin, daga cikinsu glioxal yana amsawa da sauri. Sabili da haka, ana amfani da glycoxal a matsayin wakili mai haɗin gwiwa a cikin samar da masana'antu. Matsakaicin irin wannan nau'in wakili na crosslinking a cikin maganin shine 0.2% ~ 10% na yawan ether, zai fi dacewa 7% ~ 10%, kuma 3.3% ~ 6% shine mafi dacewa ga glioxal. Yawan zafin jiki na gabaɗaya shine 0 ~ 30 ℃, kuma lokacin shine 1 ~ 120min. Ana buƙatar ɗaukar matakin haɗin kai a ƙarƙashin yanayin acidic. Gabaɗaya, ana ƙara inorganic ƙarfi acid ko Organic carboxylic acid zuwa maganin don daidaita pH na maganin zuwa kusan 2 ~ 6, zai fi dacewa tsakanin 4 ~ 6, sa'an nan kuma ana ƙara aldehydes don aiwatar da halayen haɗin kai. . Acid ɗin da aka yi amfani da su sun haɗa da hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid ko citric acid, daga cikinsu akwai formic acid ko acetic acid ya dace, kuma formic acid shine mafi kyawu. Hakanan za'a iya ƙara acid da aldehyde a lokaci guda don ba da damar mafita don haɗewa cikin kewayon pH da ake so. Ana amfani da wannan amsa sau da yawa a cikin tsarin jiyya na ƙarshe a cikin tsarin shirye-shiryen ethers cellulose. Bayan da cellulose ether ba a soluble, yana da kyau a wanke da kuma tsarkakewa da ruwa a 20 ~ 25 ° C. Lokacin da aka yi amfani da samfurin, ana iya ƙara wani abu na alkaline zuwa maganin samfurin don daidaita pH na maganin ya zama alkaline, kuma samfurin zai narke a cikin bayani da sauri. Hakanan ana amfani da wannan hanyar don maganin ether cellulose da aka yi a cikin fim sannan a sarrafa fim ɗin don sanya shi fim ɗin da ba zai iya narkewa ba.
6. Hydroxypropyl methylcellulose yana da tsayayya ga enzymes
Hydroxypropyl methylcellulose yana da tsayayya ga enzymes. A ka'idar, abubuwan da suka samo asali na cellulose, irin su kowane rukunin anhydroglucose, suna da rukunin maye gurbi mai ƙarfi, wanda ba shi da sauƙin kamuwa da ƙwayoyin cuta, amma a zahiri samfurin da aka gama lokacin da canjin canji ya wuce 1, shima enzymes zai lalata shi. wanda ke nufin cewa matakin maye gurbin kowane rukuni akan sarkar cellulose bai isa ba, kuma ƙwayoyin cuta na iya lalacewa kusa da ƙungiyoyin anhydroglucose waɗanda ba a maye gurbinsu ba don samar da sukari. , wanda ake sha a matsayin sinadirai don microorganisms. Sabili da haka, idan matakin maye gurbin etherification na cellulose yana ƙaruwa, juriya ga yashewar enzymatic na ether ether shima yana haɓaka. An ruwaito cewa ragowar danko na hydroxypropyl methylcellulose (DS=1.9) shine 13.2%, methylcellulose (DS=1.83) shine 7.3%, da methylcellulose (DS=1.66) shine 3.8%, kuma hydroxyethyl cellulose shine 1.7%. Ana iya ganin cewa ikon anti-enzyme na hydroxypropyl methylcellulose yana da ƙarfi. Sabili da haka, kyakkyawan juriya na enzyme na hydroxypropyl methylcellulose, haɗe tare da mai kyau dispersibility, thickening da film-forming kaddarorin, ana amfani da gaba ɗaya a cikin ruwa-emulsion coatings, da dai sauransu, kuma kullum baya bukatar Bugu da kari na preservatives. Duk da haka, don adana dogon lokaci na bayani ko yiwuwar gurɓatawar waje na waje, ana iya ƙara abubuwan kiyayewa a matsayin kariya, kuma za'a iya ƙayyade zaɓi bisa ga bukatun ƙarshe na mafita. Phenylmercuric acetate da manganese fluorosilicate sune masu kiyayewa masu tasiri, amma suna da duka Ɗabi'a, dole ne a biya hankali ga aikin, kuma sashi shine 1 ~ 5mg na phenylmercuric acetate a kowace lita na bayani.
7. Abubuwan da ke cikin fim din hydroxypropyl methylcellulose
Ayyukan fim din hydroxypropyl methylcellulose Hydroxypropyl methylcellulose yana da kyawawan kaddarorin samar da fim, kuma maganinsa mai ruwa-ruwa ko maganin kaushi na halitta yana mai rufi akan farantin gilashi, kuma ya zama mara launi da bayyananne bayan bushewa. Kuma fim mai tauri. Yana da juriya mai kyau da danshi kuma ya kasance mai ƙarfi a yanayin zafi mai yawa. Alal misali, ƙara hygroscopic plasticizer zai iya inganta elongation da sassauci. Don inganta sassauci, masu amfani da filastik kamar glycerin da sorbitol sun fi dacewa. Matsakaicin bayani na gaba ɗaya shine 2% ~ 3%, kuma adadin filastik shine 10% ~ 20% na ether cellulose. Idan abun ciki na plasticizer ya yi yawa, abin ƙyama na rashin ruwa na colloid zai faru a ƙarƙashin babban zafi. Ƙarfin ƙarfin fim ɗin tare da filastik da aka ƙara ya fi girma fiye da haka ba tare da filastik ba, kuma yana ƙaruwa tare da ƙara yawan adadin. Amma ga hygroscopicity na fim din, yana ƙaruwa tare da karuwar adadin filastik.
Lokacin aikawa: Oktoba-13-2022