Menene Hydroxypropyl methyl cellulose HPMC?

Hydroxypropyl methyl cellulose HPMC ne ba ionic cellulose gauraye ether a iri-iri da ionic methyl carboxymethyl cellulose gauraye ether, shi ba ya amsa da nauyi karafa. Daya oxygen radicals saboda hydroxypropyl methyl cellulose abun ciki da kuma daban-daban rabo na hydroxypropyl abun ciki da danko, ya zama daban-daban iri a kan yi, misali, high methoxyl abun ciki da low abun ciki na hydroxypropyl iri, da yi yana kusa da methyl cellulose da low methoxyl. abun ciki da babban abun ciki na nau'in hydroxypropyl, kuma aikin sa yana kusa da samar da hydroxypropyl methyl cellulose. Amma a cikin kowane iri-iri, ko da yake kawai ya ƙunshi ƙaramin adadin hydroxypropyl ko ƙaramin adadin methoxy, solubility a cikin kaushi na kwayoyin halitta ko flocculation zafin jiki a cikin maganin ruwa, akwai babban bambanci.
 
1, hydroxypropyl methyl cellulose solubility
Hydroxypropyl methyl cellulose a cikin ruwa solubility na hydroxypropyl methyl cellulose ne ainihin wani irin propylene oxide (methyl oxypropyl zobe) modified methyl cellulose, don haka shi har yanzu yana da kama da methyl cellulose ruwan sanyi mai narkewa da ruwan zafi insoluble halaye. Duk da haka, yanayin zafin gelation na gyaran hydroxy propyl ya fi na methyl cellulose a cikin ruwan zafi. Misali, danko na hydroxypropyl methylcellulose bayani mai ruwa da tsaki tare da 2% methoxy abun ciki DS=0.73 da hydroxypropyl abun ciki MS=0.46 shine 500mpa a 20℃. The gel zafin jiki na samfurin S yana kusa da 100 ℃, yayin da na methyl cellulose na wannan zafin jiki ne kawai game da 55 ℃. Amma ga solubility a cikin ruwa, kuma ya inganta sosai, alal misali, bayan murkushe hydroxypropyl methylcellulose (siffar hatsi 0.2 ~ 0.5mm a 20 ℃ 4% danko mai ruwa na 2pA? S samfurori za a iya narkar da su cikin ruwa ba tare da sanyaya a dakin da zafin jiki ba. .
 
(2) Hydroxypropyl methyl cellulose a Organic kaushi solubility na hydroxypropyl methyl cellulose a Organic kaushi solubility, shi ne kuma mafi alhẽri daga methyl cellulose, methyl cellulose bukatar a cikin methoxy maye digiri na 2.1 ko fiye kayayyakin, kuma ya ƙunshi hydroxypropyl MS=1.5 ~ 1.8 da methoxypropyl. DS=0.2 ~ 1.0, High danko hydroxypropyl methyl cellulose tare da jimlar maye gurbin sama da 1.8 yana narkewa a cikin anhydrous methanol da ethanol mafita, kuma yana da thermoplastic da ruwa mai narkewa. Hakanan yana narkewa a cikin chlorinated hydrocarbons kamar dichloromethane da trichloromethane, da sauran kaushi kamar acetone, isopropyl barasa, da diacetone barasa. Solubility a cikin kwayoyin kaushi ya fi narke ruwa.
 
2, hydroxypropyl methyl cellulose danko na abubuwan da ke tasiri
Hydroxypropyl methylcellulose danko dalilai hydroxypropyl methylcellulose daidaitaccen danko kayyade, da sauran cellulose ether iri ɗaya ne, suna a 20 ℃ tare da 2% ruwa bayani a matsayin daidaitaccen ƙaddara. Dalilin samfurin iri ɗaya, tare da karuwa na taro da karuwa, iri ɗaya na kayan abinci iri-iri na samfuran kayan aikin shine babban danko. Alakarsa da zafin jiki yayi kama da na methyl cellulose. Lokacin da zafin jiki ya tashi, danko ya fara raguwa, amma lokacin da ya kai wani zafin jiki, danko ya tashi ba zato ba tsammani kuma gelation yana faruwa. Yanayin gelation na samfurori tare da ƙananan danko ya fi girma fiye da na samfurori tare da babban danko. Matsayin ma'anar gel ɗin sa, ban da babban da ƙananan danko na ether, amma kuma tare da ether methoxy da hydroxypropyl abun da ke ciki rabo da jimlar matakin maye suna da alaƙa. Dole ne a lura cewa hydroxypropyl methylcellulose shima pseudoplastic ne; Maganin sa yana da karko lokacin da aka adana shi a dakin da zafin jiki kuma baya nuna wani lalacewa na danko sai dai yiwuwar lalatawar enzymatic.
 
3, hydroxypropyl methyl cellulose acid da alkaline juriya
Hydroxypropyl methylcellulose acid alkali hydroxypropyl methylcellulose acid da alkali, kullum yana da karko, a cikin ph PH2 ~ 12 kewayon ba a shafa ba, zai iya tsayayya da wani adadin haske acid, irin su formic acid, acetic acid, citric acid, succinic acid, phosphoric. acid, boric acid, da dai sauransu. Amma mai da hankali acid yana da tasirin rage danko. Alkaki irin su caustic soda, caustic potassium da lemun tsami ba su da wani tasiri a kansa, amma tasirin ƙara dankowar maganin zai ragu sannu a hankali nan gaba.
 
4, hydroxypropyl methyl cellulose za a iya hade
Hydroxypropyl methyl cellulose bayani za a iya gauraye da ruwa-mai narkewa polymer mahadi, da kuma zama uniform m bayani tare da mafi girma danko. Wadannan high kwayoyin mahadi su ne polyethylene glycol, polyvinyl acetate, polysilicon, polymethyl vinyl siloxane da hydroxyethyl cellulose da methyl cellulose, da dai sauransu Halitta polymer mahadi irin su danko Larabci, fara bean danko, ƙaya itace danko da sauransu. mafita. Hydroxypropyl methyl cellulose kuma za a iya hade da stearic acid ko palmitic acid mannitol ester ko sorbitol ester, amma kuma tare da glycerol, sorbitol da mannitol, wadannan mahadi za a iya amfani da matsayin hydroxypropyl methyl cellulose plasticizer.
 
5, hydroxypropyl methyl cellulose mai narkewa ruwa mai narkewa
Hydroxypropyl methyl cellulose insoluble ruwa-soluble cellulose ether, na iya zama surface giciye-linking da aldehydes, da kuma sanya wadannan ruwa-soluble ether precipitated a cikin bayani, zama insoluble a cikin ruwa. Kuma yin hydroxypropyl methylcellulose aldehyde insoluble aldehyde, formaldehyde, glioxal, succinaldehyde, dialdehyde, da dai sauransu, yin amfani da formaldehyde ya kamata kula da musamman da hankali ga PH darajar da bayani, wanda glioxal dauki sauri, don haka a masana'antu samar da aka saba amfani da glioxal a matsayin giciye. -wakilin haɗi. Matsakaicin irin wannan nau'in wakili na crosslinking a cikin bayani shine 0.2% ~ 10% na ether mass, mafi kyau shine 7% ~ 10%, kamar amfani da glioxal tare da 3.3% ~ 6% shine mafi dacewa. Yawan zafin jiki na gabaɗaya shine 0 ~ 30 ℃, lokacin shine 1 ~ 120min. Ana buƙatar ɗaukar matakin haɗin kai a ƙarƙashin yanayin acidic. Gabaɗaya, ana ƙara inorganic ƙarfi acid ko Organic carboxylic acid a cikin bayani don daidaita PH na maganin zuwa kusan 2 ~ 6, zai fi dacewa tsakanin 4 ~ 6, sannan ana ƙara aldehydes don haɗin kai. Abubuwan da ake amfani da su sune hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxy acetic acid, succinic acid ko citric acid, daga cikinsu formic acid ko acetic acid shine mafi kyau, yayin da formic acid shine mafi kyau. Hakanan za'a iya ƙara acid da aldehydes a lokaci guda don ba da damar haɗe-haɗe a cikin kewayon PH da ake so. Ana amfani da wannan amsa sau da yawa a cikin tsari na ƙarshe na tsarin shirye-shiryen ether cellulose, don haka ether cellulose ba ya narke, mai sauƙin amfani da ruwa 20 ~ 25 ℃ don wankewa da tsarkakewa. Lokacin da aka yi amfani da samfurin, ana iya ƙara abubuwan alkaline zuwa maganin samfurin don daidaita PH na maganin ya zama alkaline, kuma samfurin yana narkewa cikin sauri a cikin bayani. Hakanan za'a iya amfani da wannan hanyar lokacin da aka yi amfani da maganin ether na cellulose don yin fim sannan a yi amfani da fim ɗin don yin fim ɗin da ba zai iya narkewa ba.
 
6, hydroxypropyl methyl cellulose anti-enzyme
Hydroxypropyl methyl cellulose enzyme juriya na cellulose abũbuwan amfãni a cikin ka'idar, kamar kowane anhydroglucose kungiyoyin kamar akwai m hade da maye gurbin kungiyoyin, yashwa na microorganisms ne kasa mai saukin kamuwa da kamuwa da cuta, amma a gaskiya da ƙãre samfurin maye gurbin darajar fiye da 1. Hakanan ta hanyar lalatawar enzyme, wannan shine bayanin kowane rukuni a cikin digirin maye gurbin sarkar cellulose ba iri ɗaya bane, ƙananan ƙwayoyin cuta na iya lalatawa kusa. Ƙungiyoyin glucose da ba a maye gurbinsu ba don samar da sukari, waɗanda ƙananan ƙwayoyin cuta za su iya cinye su azaman abinci. Sabili da haka, idan matakin maye gurbin etherification na cellulose ya karu, za a inganta juriya na ether cellulose zuwa yashwar enzymatic. An ba da rahoton cewa a ƙarƙashin yanayin sarrafawa, ragowar danko na hydroxypropyl methyl cellulose (DS=1.9), methyl cellulose (DS=1.83), methyl cellulose (DS=1.66), da hydroxyethyl cellulose (1.7%) shine 13.2%, 7.3% 3.8%, da kuma 1.7%, bi da bi. Hydroxypropyl methyl cellulose yana da karfi anti-enzyme ikon. Saboda haka hydroxypropyl methylcellulose m anti-enzyme, hade tare da kyau watsawa, thickening da fim samuwar, amfani a emulsion coatings, da dai sauransu, kullum ba sa bukatar ƙara preservatives. Duk da haka, don hana ajiya na dogon lokaci na bayani ko yiwuwar gurɓata daga waje, za'a iya ƙara abubuwan da aka tsara, wanda za'a iya ƙayyade zaɓin su bisa ga bukatun ƙarshe na bayani. Phenylmercuric acetate da manganese fluosilicate suna da tasiri masu tasiri, amma suna da guba kuma dole ne a sarrafa su a hankali. Gabaɗaya, ana iya ƙara 1 ~ 5mg phenylmercuric acetate zuwa kowace lita na bayani.
 
7, hydroxypropyl methyl cellulose membrane aiki
Hydroxypropyl methyl cellulose film yi na hydroxypropyl methyl cellulose yana da kyau kwarai fim, ta ruwa mai ruwa bayani ko Organic sauran ƙarfi bayani, mai rufi a kan gilashin farantin, bayan bushewa zama colorless, m da m fim. Yana da juriya mai kyau da danshi kuma ya kasance mai ƙarfi a yanayin zafi mai yawa. Irin su ƙari na hygroscopic plasticizer, zai iya haɓaka haɓakawa da sassauci, don inganta haɓakawa, glycerol da sorbitol da sauran filastik sun fi dacewa. Mahimmancin bayani na gaba ɗaya shine 2% ~ 3%, ƙwayar filastik shine 10% ~ 20% na ether cellulose. Idan abun ciki na plasticizer yana da kyau, yanayin raguwa na rashin ruwa na colloid zai iya faruwa a cikin babban zafi. Ƙarfin ƙarfi na fim ɗin da aka kara da filastik ya fi girma fiye da wanda ba a kara ba, kuma yana ƙaruwa tare da ƙara yawan adadin da aka kara, kamar yadda ga hygroscopicity na fim din kuma yana karuwa tare da karuwar adadin filastik.