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Hydroxypropyl Methyl Cellulose HPMC Āhuatanga

Ko te Hydroxypropyl methylcellulose HPMC he ahua o te cellulose kore-ionic i konatunatua ether. He rereke mai i te katote methyl carboxymethyl cellulose i konatunatua ether, kaore e tauhohe ki nga konganuku taumaha. Na te rereke o nga rereketanga o te ihirangi methoxyl me te ihirangi hydroxypropyl i roto i te hydroxypropyl methylcellulose me te rereke rereke, he maha nga momo me nga ahuatanga rereke, hei tauira, te nui o te methoxyl me te iti o te waikawa hydroxypropyl Ko tana mahi he tata ki te methyl cellulose, i te mea ko te mahi a he iti te ihirangi methoxy me te ihirangi hydroxypropyl teitei e tata ana ki tera o te hydroxypropyl methyl cellulose. Heoi, i roto i ia momo, ahakoa he iti noa te roopu hydroxypropyl, he roopu methoxyl iti ranei kei roto, he tino rerekee te whakarewatanga i roto i nga whakarewa pararopi, te pāmahana karekau ranei i roto i te wairewa wai.
 
1. Te memehatanga o te hydroxypropyl methylcellulose
①Ko te wairewa o te hydroxypropyl methylcellulose i roto i te wai Ko te Hydroxypropyl methylcellulose he momo methylcellulose kua whakarereketia e te propylene oxide (methoxypropylene), no reira he rite tonu nga ahuatanga ki te methyl cellulose He rite nga ahuatanga o te wairewa makariri me te wai wera. Heoi, na te roopu hydroxypropyl kua whakarereketia, he nui ake te pāmahana o te wai wera i tera o te methyl cellulose. Hei tauira, ko te viscosity o te wairewa wai hydroxypropyl methylcellulose me te 2% methoxy content substitution degree DS=0.73 me te hydroxypropyl content MS=0.46 he hua o te 500 mpa?s i te 20°C, me tona pāmahana reera Ka taea te tata ki te 100° C, i te mea ko te methyl cellulose i te taurite he 55°C noa iho. Mo tona whakakorenga ki te wai, kua tino pai ake. Hei tauira, ka taea te hoko i te hydroxypropyl methylcellulose (he hua me te rahi matūriki o te 0.2~0.5mm me te 4% wairewa wai pokey o te 2pa?s i te 20°C ka taea te hoko i I te pāmahana rūma, he ngawari te whakarewa i te wai me te kore whakamatao. .
 
②Ko te wairewa o te hydroxypropyl methylcellulose i roto i nga whakarewa pararopi He pai ake hoki te whakarewatanga o te hydroxypropyl methylcellulose i roto i nga whakarewa pararopi i tera o te methylcellulose. Mo nga hua kei runga ake i te 2.1,hydroxypropyl methylcellulose teitei-nuikei roto te hydroxypropyl MS = 1.5 ~ 1.8 me te methoxy DS = 0.2 ~ 1.0, me te tohu katoa o te whakakapi i runga ake i te 1.8, ka whakarewahia i roto i te methanol anhydrous me te wairewa wairewa Waenga, me te thermoplastic me te wai-wairewa. He wairewa ano i roto i nga waiwaro maataa penei i te methylene chloride me te chloroform, me nga whakarewa waro penei i te acetone, isopropanol me te waipiro diacetone. He pai ake te whakarewatanga o te wairewa i te wairewa.
 
2. Nga mea e pa ana ki te pokey o te hydroxypropyl methylcellulose
Ko nga mea e Whakaawe ana i te Viscosity o Hydroxypropyl Methyl Cellulose Ko te whakatau i te viscosity paerewa o te hydroxypropyl methyl cellulose he rite tonu ki era atu etera cellulose. Ka ine ki te 20°C me te 2% wairewa wai hei paerewa. Ko te pokey o taua hua ka piki ake i te pikinga o te kukū. Mo nga hua he rereke nga taumahatanga ngota i te kukū kotahi, ko te hua he nui ake te taumaha ngota he nui ake te pokey. Ko tona hononga ki te pāmahana he rite ki te methyl cellulose. Ka piki ake te pāmahana, ka timata te heke o te pokey, engari ka tae ki tetahi pāmahana, ka piki ohorere te pokey ka puta te wai. He teitei ake te mahana o te reera o nga hua iti-viscosity. he tiketike. Ko tana tohu gel e kore e pa ana ki te pokey o te ether anake, engari e pa ana ki te ōwehenga hanganga o te roopu methoxyl me te roopu hydroxypropyl i roto i te ether me te rahi o te tohu whakakapinga katoa. Me tohu ko te hydroxypropyl methylcellulose he pseudoplastic hoki, a ka pumau tana otinga i te pāmahana rūma kaore he paheketanga o te pokey engari mo te tupono o te whakahekenga enzymatic.
 
3. Hydroxypropyl methylcellulose he ātete ki te waikawa me te alkali
Hydroxypropyl methylcellulose acid and alkali resistance Hydroxypropyl methylcellulose is usually stable to acids and alkalis, and is not affect in the range of pH 2~12. Ka taea e ia te tu atu i te nui o te waikawa marama, Pērā i te waikawa formic, te waikawa acetic, te waikawa citric, te waikawa succinic, te waikawa phosphoric, te waikawa boric, me etahi atu. Engari ko te waikawa kukū te hua o te whakaiti i te pokey. Karekau he painga ki runga i te wai kawa, penei i te houra, te paura wai me te kotakota, engari ka taea te whakanui ake i te pokey o te otinga, katahi ka ata heke iho.
 
4. Te koretake o te hydroxypropyl methylcellulose
Te pohehe o te wairewa hydroxypropyl methylcellulose Hydroxypropyl methylcellulose ka taea te konatunatua ki te wai-wairewa polymer pūhui kia noho rite, kia marama te otinga me te pokey teitei ake. Ko enei pūhui polymer ko te polyethylene glycol, polyvinyl acetate, polysilicone, polymethylvinylsiloxane, hydroxyethyl cellulose, me te methyl cellulose. He pai hoki te hototahitanga o nga puhui irapoi teitei penei i te kapia arabic, te kapia mawhitiwhiti, te kapia karaya, me etahi atu. Ko te Hydroxypropyl methylcellulose ka taea ano te whakauru ki te mannitol ester, sorbitol ester ranei o te waikawa stearic, te waikawa palmitic ranei, ka taea hoki te whakauru ki te glycerin, te sorbitol me te mannitol, a ka taea te whakamahi i enei pūhui hei Plasticizer hydroxypropyl methylcellulose mo te cellulose.
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5. Te whakakorekore me te wairewa o te hydroxypropyl methylcellulose
Ko nga etera cellulose kore-wai-wairewa o te hydroxypropyl methylcellulose ka taea te hono-whiti ki nga aldehydes i runga i te mata, kia tohe ai enei etera wairewa i roto i te wairewa ka kore e rewa ki te wai. Ko nga aldehydes e hanga ana i te hydroxypropyl methylcellulose kia kore e rewa ko formaldehyde, glyoxal, succinic aldehyde, adipaldehyde, me etahi atu. Ina whakamahi formaldehyde, me aro nui ki te uara pH o te otinga, he tere ake te urupare o te glyoxal, no reira ka whakamahia te glyoxal hei hononga whakawhiti. kaihoko i roto i te hanga ahumahi. Ko te nui o tenei ahua o te kaihoko whakawhiti i roto i te otinga ko te 0.2% ~ 10% o te papatipu o te ether, he pai ki te 7% ~ 10%, hei tauira, ko te 3.3% ~ 6% o te glyoxal te mea tino pai. Ko te pāmahana maimoatanga whānui ko 0 ~ 30 ℃, me te wa ko 1 ~ 120min. Me whakahaere te tauhohenga honohono i raro i nga tikanga waikawa. Ko te tikanga, ka taapiri tuatahihia te otinga ki te waikawa kaha pararopi, waikawa warowaiwa ranei hei whakatika i te pH o te otinga ki te 2~6, he pai ake i waenga i te 4~6, katahi ka taapirihia nga aldehydes hei kawe i te tauhohenga honohono. Ko te waikawa i whakamahia he waikawa waikawa, he waikawa pungatara, he waikawa phosphoric, he waikawa formic, he waikawa acetic, he waikawa hydroxyacetic, he waikawa succinic, he waikawa citric me etahi atu, he mea pai ki te whakamahi i te waikawa formic, waikawa acettic ranei, me te waikawa formic he tino pai. Ka taea hoki te taapiri i te waikawa me te aldehyde i te wa kotahi ki te tuku i te otinga kia uru ki te tauhohenga honohono i roto i te awhe pH e hiahiatia ana. Ka whakamahia tenei tauhohenga i roto i te tukanga maimoatanga whakamutunga i roto i te whakaritenga o nga eter cellulose. I muri i te ether cellulose he koretake, he pai ki te horoi me te purea ki te wai i te 20 ~ 25 ° C. I te wa e whakamahia ana te hua, ka taea te taapiri i nga matū kawakore ki te otinga o te hua hei whakatika i te pH o te otinga kia kawakore, ka tere te memeha o te hua ki te otinga. Ko tenei tikanga e pa ana ki te maimoatanga o te kiriata i muri i te hanga o te otinga cellulose ether hei kiriata kia waiho hei kiriata korekore.
 
6. Te ātete o te pūmua o te hydroxypropyl methylcellulose
Ko te parenga o te haurangi o te hydroxypropyl methylcellulose ko nga hua o te cellulose, penei i ia roopu anhydroglucose, ki te mea he roopu whakakapi e piri ana, ehara i te mea ngawari ki te pangia e nga microorganisms, engari ko te mea kua oti te hua Ina neke atu te uara whakakapinga ki te 1, ka ka whakahekehia ano e nga enzymes, ko te tikanga ko te tohu o te whakakapinga o ia roopu i runga i te mekameka cellulose kaore i te tino rite, a ka taea e nga microorganisms te horo i runga i te roopu anhydroglucose kaore i whakakapi ki te hanga huka, hei matūkai mo nga microorganisms ki te mimiti. No reira, ki te piki ake te tohu o te whakakapinga whakaeera o te cellulose, ka piki ano te aukati ki te horo enzymatic o te cellulose ether. E ai ki nga purongo, i raro i nga tikanga whakahaere, ko nga hua o te hydrolysis o nga enzymes, ko te toenga viscosity o te hydroxypropyl methylcellulose (DS=1.9) he 13.2%, ko te methylcellulose (DS=1.83) he 7.3%, ko te methylcellulose (DS=1.66) he 3.8%, me te hydroxyethyl cellulose he 1.7%. Ka kitea he kaha te kaha o te hydroxypropyl methylcellulose ki te anti-enzyme. Na reira, ko te tino pai o te aukati o te waikawa o te hydroxypropyl methylcellulose, me te pai o te whakamararatanga, te matotoru me te hanga kiriata, ka whakamahia i roto i nga paninga wai-emulsion, me etahi atu, me te nuinga kaore e hiahia ki te taapiri i nga rongoa. Engari, mo te wa roa mo te rokiroki o te otinga, ka taea ranei te poke mai i waho, ka taea te taapiri i nga whakamarumaru hei whakatupato, a ka taea te whakatau i te whiringa i runga i nga whakaritenga whakamutunga o te otinga. Ko te Phenylmercuric acetate me te manganese fluorosilicate he rongoa whai hua, engari kei a raatau katoa te Toxicity, me aro ki te mahi. Ko te tikanga, ka taea te taapiri 1~5mg o te phenylmercury acetate ki te otinga mo ia rita o te inenga.
 
7. Mahinga o te membrane hydroxypropyl methylcellulose
Ko te mahinga o te kiriata hydroxypropyl methylcellulose Hydroxypropyl methylcellulose he tino pai nga ahuatanga hanga kiriata. Ka whakakikoruatia tana wairewa wai, he wairewa pararopi ranei ki runga i te pereti karaihe, ka kore te tae, ka marama i muri i te whakamaroketanga. Me te kiriata uaua. He pai te aukati makuku me te pumau tonu i nga wera teitei. Mena ka taapirihia te whakamaarama hygroscopic, ka taea te whakaroa me te ngawari. I runga i te whakapai ake i te ngawari, ko nga kaiparapara penei i te glycerin me te sorbitol te mea tino pai. Ko te tikanga, ko te kukū otinga ko 2% ~ 3%, me te nui o te plasticizer ko 10% ~ 20% o te cellulose ether. Mena he tiketike rawa te ihirangi o te plasticizer, ka paheke te paheketanga colloidal i te makuku nui. Ko te kaha tensile o te kiriata taapiri me te plasticizer he nui ake i tera kaore he taapiri, ka piki ake me te piki haere o te moni taapiri, ka piki ano te hygroscopicity o te kiriata me te piki o te nui o te plasticizer.


Wā tuku: Tihema-19-2022
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