Hydroxypropyl methylcellulose HPMC wani nau'i ne na cellulose wanda ba na ionic ba.Ba kamar ionic methyl carboxymethyl cellulose gauraye ether, shi ba ya amsa da nauyi karafa.Saboda ma'auni daban-daban na abun ciki na methoxyl da abun ciki na hydroxypropyl a cikin hydroxypropyl methylcellulose da viscosities daban-daban, akwai nau'o'in nau'i daban-daban tare da kaddarorin daban-daban, misali, babban abun ciki na methoxyl da ƙananan abun ciki na hydroxypropyl Ayyukansa yana kusa da na methyl cellulose, yayin da na ƙananan. Abun cikin methoxyl da babban abun ciki na hydroxypropyl yana kusa da na hydroxypropyl methyl cellulose.Duk da haka, a cikin kowane iri-iri, kodayake ƙananan ƙungiyar hydroxypropyl ko ƙananan ƙungiyar methoxyl yana ƙunshe, akwai bambance-bambance masu yawa a cikin solubility a cikin magungunan kwayoyin halitta ko yanayin zafi a cikin maganin ruwa.
(1) Abubuwan solubility na hydroxypropyl methylcellulose
① Solubility na hydroxypropyl methylcellulose a cikin ruwa Hydroxypropyl methylcellulose ne ainihin wani irin methylcellulose modified da propylene oxide (methoxypropylene), don haka shi har yanzu yana da guda Properties kamar yadda methyl cellulose Cellulose yana da irin wannan halaye na ruwan sanyi solubility da ruwan zafi insolubility.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, danko na hydroxypropyl methylcellulose mai ruwa bayani tare da 2% methoxy abun ciki maye gurbin digiri DS=0.73 da hydroxypropyl abun ciki MS=0.46 shine 500mpa·s a 20°C, kuma gel zazzabi Zai iya kaiwa kusa da 100°C, yayin da methyl cellulose a cikin zafin jiki guda yana da kusan 55 ° C.Dangane da narkewar sa a cikin ruwa, shi ma an inganta shi sosai.Misali, za'a iya siyan hydroxypropyl methylcellulose mai nisa (siffar granular 0.2 ~ 0.5mm a 20 ° C tare da dankowar ruwa na 4% na 2pa•s a cikin dakin da zazzabi, yana iya narkewa cikin ruwa ba tare da sanyaya ba.
②Solubility na hydroxypropyl methylcellulose a cikin kwayoyin kaushi Narkewar hydroxypropyl methylcellulose a cikin kwayoyin kaushi kuma ya fi na methylcellulose kyau.Don samfurori sama da 2.1, high-danko hydroxypropyl methylcellulose dauke da hydroxypropyl MS = 1.5 ~ 1.8 da methoxy DS = 0.2 ~ 1.0, tare da jimlar digiri na maye gurbin sama da 1.8, shi ne mai narkewa a cikin anhydrous methanol da ethanol mafita Medium, da thermoplastic da ruwa-soluble mafita. .Hakanan yana narkewa a cikin chlorinated hydrocarbons kamar methylene chloride da chloroform, da sauran kaushi kamar acetone, isopropanol da diacetone barasa.Solubility a cikin kwayoyin kaushi yana da kyau fiye da solubility na ruwa.
(2) Abubuwan da suka shafi danko na hydroxypropyl methylcellulose Daidaitaccen ƙaddarar danko na hydroxypropyl methylcellulose daidai yake da sauran ethers cellulose, kuma an auna shi a 20 ° C tare da 2% bayani mai ruwa kamar yadda ma'auni.Danko na samfurin iri ɗaya yana ƙaruwa tare da haɓaka haɓaka.Don samfurori tare da sikelin kwayoyin halitta daban-daban a daidai maida hankali, samfurin tare da babban nauyin kwayoyin yana da danko.Alakarsa da zafin jiki yayi kama da na methyl cellulose.Lokacin da zafin jiki ya tashi, danko zai fara raguwa, amma idan ya kai wani yanayi.
danko ba zato ba tsammani ya tashi kuma gelation yana faruwa.Zazzaɓin 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, har ma yana da alaƙa da rabon abun ciki na ƙungiyar metoxyl da ƙungiyar hydroxypropyl a cikin ether da girman jimlar digirin maye gurbin.Dole ne a lura cewa hydroxypropyl methylcellulose shima pseudoplastic ne, kuma maganin sa yana da ƙarfi a cikin zafin jiki ba tare da wani lalacewa a cikin danko ba sai don yuwuwar lalatawar enzymatic.
(3) Haƙurin gishiri na hydroxypropyl methylcellulose Tunda hydroxypropyl methylcellulose ba shi da ether, ba ya ionize a cikin kafofin watsa labaru na ruwa, sabanin sauran ionic cellulose ethers, misali, carboxymethyl cellulose reacts da nauyi karfe ions da precipitates fita a cikin bayani.Gabaɗaya gishiri irin su chloride, bromide, phosphate, nitrate, da sauransu.Koyaya, ƙari na gishiri yana da ɗan tasiri akan yanayin zafi na flocculation maganin ruwa.Lokacin da gishiri gishiri ya karu, yawan zafin jiki na gel yana raguwa.Lokacin da maida hankali gishiri ya kasance ƙasa da wurin flocculation, danko na maganin yana ƙoƙarin ƙarawa.Saboda haka, ana ƙara wani adadin gishiri., a aikace-aikace, zai iya cimma thickening sakamako more tattalin arziki.Sabili da haka, a wasu aikace-aikacen, yana da kyau a yi amfani da cakuda ether cellulose da gishiri fiye da babban taro na ether bayani don cimma sakamako mai girma.
(4) Hydroxypropyl methylcellulose acid da juriya na alkali Hydroxypropyl methylcellulose gabaɗaya ba su da ƙarfi ga acid da alkalis, kuma ba a shafa su cikin kewayon pH 2 ~ 12.Yana iya jure wani adadi na Light acid, irin su formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, da dai sauransu. Amma maida hankali acid yana da tasirin rage danko.Alkalai irin su caustic soda, caustic potash da ruwan lemun tsami ba su da wani tasiri a kai, amma suna iya kara dankowar maganin, sannan a rage shi a hankali.
(5) Rashin daidaituwa na hydroxypropyl methylcellulose Hydroxypropyl methylcellulose bayani za a iya haxa shi da ruwa mai narkewa polymer mahadi ya zama uniform da m bayani tare da mafi girma danko.Wadannan mahadi na polymer sun hada da polyethylene glycol, polyvinyl acetate, polysilicon, polymethylvinylsiloxane, hydroxyethyl cellulose, da methyl cellulose.Haɗaɗɗen maɗaukakin ƙwayoyin halitta irin su gumakan arabic, ɗan waken fari, karaya danko, da dai sauransu suma suna da dacewa sosai tare da maganin sa.Hydroxypropyl methylcellulose kuma ana iya haɗa shi da mannitol ester ko sorbitol ester na stearic acid ko palmitic acid, kuma ana iya haɗa shi da glycerin, sorbitol da mannitol, kuma ana iya amfani da waɗannan mahadi azaman hydroxypropyl methylcellulose Plasticizer don cellulose.
(6) Ethers cellulose da ba a iya narkewa da ruwa mai narkewa na hydroxypropyl methylcellulose za a iya haɗa su tare da aldehydes a saman, don haka waɗannan ethers masu narkewar ruwa suna tasowa a cikin bayani kuma su zama marasa narkewa a cikin ruwa.Aldehydes da ke yin hydroxypropyl methylcellulose insoluble sun hada da formaldehyde, glioxal, succinic aldehyde, 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 , don haka ana amfani da glioxal a matsayin giciye. wakili a cikin samar da masana'antu.Adadin irin wannan nau'in wakili mai haɗin kai a cikin bayani shine 0.2% ~ 10% na yawan adadin ether, zai fi dacewa 7% ~ 10%, misali, 3.3% ~ 6% na glioxal shine mafi dacewa.Gabaɗaya, maganin
zazzabi shine 0 ~ 30 ℃, kuma lokacin shine 1 ~ 120min.Ana buƙatar ɗaukar matakin haɗin kai a ƙarƙashin yanayin acidic.Gabaɗaya, an fara ƙara maganin tare da acid mai ƙarfi na inorganic ko Organic carboxylic acid don daidaita pH na maganin zuwa kusan 2 ~ 6, zai fi dacewa tsakanin 4 ~ 6, sannan ƙara aldehydes don aiwatar da halayen haɗin kai.Acid da aka yi amfani da shi yana da hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid ko citric acid da dai sauransu, inda tare da formic acid ko acetic acid yana da kyau, kuma formic acid shine mafi kyau.Hakanan za'a iya ƙara acid da aldehyde a lokaci guda don ba da damar maganin ya sami hanyar haɗin kai a 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 ether cellulose ba shi da narkewa, ya dace don amfani
20 ~ 25 ℃ ruwan wanka da tsarkakewa.Lokacin da ake amfani da samfurin, ana iya ƙara abubuwan 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 fim ɗin bayan an yi maganin ether cellulose a cikin fim don sanya shi fim ɗin da ba zai iya narkewa ba.
(7) The enzyme juriya na hydroxypropyl methylcellulose ne a ka'idar cellulose abubuwan, kamar kowane anhydroglucose kungiyar, idan akwai da tabbaci bonded substituent kungiyar, shi ne ba sauki a kamuwa da microorganisms, amma a gaskiya da ƙãre samfurin Lokacin da musanya darajar ya wuce. 1, Hakanan za'a lalata shi ta hanyar enzymes, wanda ke nufin cewa matakin maye gurbin kowane rukuni akan sarkar cellulose bai isa ba, kuma ƙwayoyin cuta na iya lalata ƙungiyar anhydroglucose da ba a canza su ba don samar da sukari, azaman abubuwan gina jiki don ƙwayoyin cuta don sha.Saboda haka, idan matakin etherification maye gurbin cellulose ya karu, juriya ga enzymatic yashwa na cellulose ether kuma zai karu.Dangane da rahotanni, a ƙarƙashin yanayin sarrafawa, sakamakon hydrolysis na enzymes, ragowar danko na hydroxypropyl methylcellulose (DS=1.9) shine 13.2%, methylcellulose (DS=1.83) shine 7.3%, methylcellulose (DS=1.66) shine 3.8%, kuma hydroxyethyl cellulose shine 1.7%.Ana iya ganin cewa hydroxypropyl methylcellulose yana da ƙarfin anti-enzyme mai ƙarfi.Saboda haka, mafi kyaun enzyme juriya na hydroxypropyl methylcellulose, haɗe tare da mai kyau dispersibility, thickening da film-forming Properties, ana amfani da ruwa-emulsion coatings, da dai sauransu, kuma kullum ba ya bukatar ƙara preservatives.Duk da haka, don adana dogon lokaci na bayani ko yiwuwar gurɓata daga waje, za'a iya ƙara abubuwan kiyayewa a matsayin kariya, kuma za'a iya ƙayyade zaɓin bisa ga bukatun ƙarshe na bayani.Phenylmercuric acetate da manganese fluorosilicate suna da tasiri masu mahimmanci, amma duk suna da guba, dole ne a biya hankali ga aikin.Gabaɗaya, ana iya ƙara 1 ~ 5mg na phenylmercury acetate zuwa maganin kowace lita na sashi.
(8) Ayyukan fim din hydroxypropyl methylcellulose Hydroxypropyl methylcellulose yana da kyawawan kaddarorin yin fim.Maganin ruwan sa ko maganin kaushi na halitta ana lullube shi akan farantin gilashi, kuma ya zama mara launi da bayyane bayan bushewa.Kuma fim mai tauri.Yana da juriya mai kyau da danshi kuma ya kasance mai ƙarfi a yanayin zafi mai yawa.Idan an ƙara hygroscopic plasticizer, za a iya inganta elongation da sassauci.Dangane da inganta sassauci, masu yin filastik irin su glycerin da sorbitol sun fi dacewa.Gabaɗaya, ƙaddamarwar maganin shine 2% ~ 3%, kuma adadin filastik shine 10% ~ 20% na ether cellulose.Idan abun ciki na filastikizer ya yi yawa, raguwar bushewar colloidal zai faru a babban zafi.Ƙarfin ƙarfi na fim ɗin tare da
plasticizer da aka kara ya fi girma fiye da haka ba tare da filastik ba, kuma yana ƙaruwa tare da karuwar adadin da aka ƙara.Amma ga hygroscopicity na fim din, yana ƙaruwa tare da ƙara yawan adadin filastik.
Lokacin aikawa: Nuwamba-24-2022