Hydroxypropyl methyl cellulose HPMC jẹ iru ti kii-ionic cellulose adalu ether, eyi ti o yatọ si ionic methyl carboxymethyl cellulose adalu ether, ati awọn ti o ko ni fesi pẹlu eru awọn irin.Nitori awọn ipin oriṣiriṣi ti akoonu methoxyl ati akoonu hydroxypropyl ni hydroxypropyl methylcellulose ati awọn viscosities ti o yatọ, o ti di ọpọlọpọ awọn oriṣiriṣi pẹlu awọn ohun-ini oriṣiriṣi, fun apẹẹrẹ, akoonu methoxyl giga ati akoonu hydroxypropyl kekere Išẹ rẹ sunmọ ti methyl cellulose, ati awọn oriṣiriṣi pẹlu akoonu methoxyl kekere ati akoonu hydroxypropyl giga, iṣẹ ṣiṣe rẹ sunmọ ti hydroxypropyl methylcellulose.Bibẹẹkọ, ni awọn oriṣiriṣi oriṣiriṣi, botilẹjẹpe iye kekere ti ẹgbẹ hydroxypropyl tabi iye kekere ti ẹgbẹ methoxy wa ninu, solubility ni awọn olomi Organic tabi iwọn otutu flocculation ni ojutu olomi yatọ pupọ.
1. Solubility ti hydroxypropyl methylcellulose
① Solubility ti hydroxypropyl methyl cellulose ninu omi Hydroxypropyl methyl cellulose jẹ kosi kan methyl cellulose títúnṣe nipasẹ propylene oxide (methyl oxypropylene), ki o si tun ni awọn ohun-ini kanna bi methyl cellulose.Cellulose jẹ iru ni isokuso omi tutu ati ailagbara omi gbona.Sibẹsibẹ, nitori ẹgbẹ hydroxypropyl ti a ṣe atunṣe, iwọn otutu gelation rẹ ninu omi gbona ga pupọ ju ti methyl cellulose lọ.Fun apẹẹrẹ, iki ti ojutu olomi ti hydroxypropyl methylcellulose pẹlu 2% akoonu methoxyl DS=0.73 ati akoonu hydroxypropyl MS=0.46 jẹ 500 mpa?s ni 20°C.Iwọn gel rẹ O le de ọdọ 100°C, lakoko ti methylcellulose ni iwọn otutu kanna jẹ nipa 55°C.Bi fun isokan ninu omi, o tun ti ni ilọsiwaju pupọ.Fun apẹẹrẹ, awọn pulverized hydroxypropyl methylcellulose (granular apẹrẹ ti 0.2 ~ 0.5mm ni 20 ° C pẹlu kan iki ti 4% aqueous ojutu soke si 2pa?s le ṣee lo ni Ni yara otutu, o jẹ awọn iṣọrọ tiotuka ninu omi lai itutu.
② Awọn solubility ti hydroxypropyl methyl cellulose ni Organic solvents The solubility ti hydroxypropyl methyl cellulose ni Organic epo jẹ tun dara ju ti methyl cellulose, ati methyl cellulose nilo lati ni a ìyí ti methoxyl aropo ni Awọn ọja loke 2.1, ati ki o ga-viscosity hydroxypropyl methylcellulose ni ninu. hydroxypropyl MS=1.5 ~ 1.8 ati methoxy DS=0.2 ~ 1.0, ati iwọn aropo lapapọ loke 1.8 jẹ tiotuka ni kẹmika anhydrous ati awọn ojutu ethanol alabọde, thermoplastic ati omi-tiotuka.O tun jẹ tiotuka ninu awọn hydrocarbons chlorinated gẹgẹbi dichloromethane ati chloroform, ati ninu awọn nkanmimu Organic gẹgẹbi acetone, isopropanol ati ọti diacetone.Solubility rẹ ni awọn nkan ti o nfo Organic dara ju omi-tiotuka lọ.
2. Awọn okunfa ti o ni ipa lori iki ti hydroxypropyl methylcellulose
Awọn okunfa ipa ti hydroxypropyl methyl cellulose viscosity Ipinnu viscosity boṣewa ti hydroxypropyl methyl cellulose, bii awọn ethers cellulose miiran, da lori 2% ojutu olomi ni 20°C.Igi ti ọja kanna pọ si pẹlu ilosoke ti ifọkansi.Fun awọn ọja pẹlu awọn iwuwo molikula oriṣiriṣi ni ifọkansi kanna, awọn ọja pẹlu awọn iwuwo molikula nla ni iki ti o ga julọ.Ibasepo rẹ pẹlu iwọn otutu jẹ iru si ti methyl cellulose.Nigbati iwọn otutu ba pọ si, iki bẹrẹ lati dinku, ṣugbọn nigbati o ba de iwọn otutu kan, iki naa yoo pọ si lojiji ati gelation waye.Awọn iwọn otutu jeli ti awọn ọja iki kekere jẹ ti o ga julọ.ga.Ojuami gel rẹ kii ṣe ibatan si iki ti ether nikan, ṣugbọn tun si ipin tiwqn ti methoxy ati hydroxypropyl ninu ether ati iwọn aropo lapapọ.O gbọdọ ṣe akiyesi pe hydroxypropyl methylcellulose tun jẹ pseudoplastic ati pe ojutu rẹ jẹ iduroṣinṣin ni iwọn otutu yara laisi eyikeyi ibajẹ ti iki ayafi iṣeeṣe ibajẹ enzymatic.
3. Hydroxypropyl methylcellulose acid ati alkali resistance
Hydroxypropyl methylcellulose acid ati alkali resistance Hydroxypropyl methylcellulose jẹ iduroṣinṣin gbogbogbo si acid ati alkali, ati pe ko ni ipa ni iwọn pH 2 ~ 12.O le withstand kan awọn iye ti ina acid.Bi formic acid, acetic acid, citric acid, succinic acid, phosphoric acid, boric acid, bbl Sibẹsibẹ, ogidi acid ni ipa ti idinku iki.Alkali gẹgẹbi omi onisuga caustic, potash caustic ati omi orombo wewe ko ni ipa lori rẹ, ṣugbọn o le mu iki ti ojutu pọ si diẹ, lẹhinna iṣẹlẹ yoo wa ti idinku lọra ni ọjọ iwaju.
4. Mixability ti hydroxypropyl methylcellulose
Aiṣedeede ti Hydroxypropyl Methyl Cellulose ojutu Hydroxypropyl methyl cellulose ni a le dapọ pẹlu agbo-ẹda polima ti omi-tiotuka lati di aṣọ aṣọ ati ojutu sihin pẹlu iki ti o ga julọ.Awọn agbo ogun polymer wọnyi pẹlu polyethylene glycol, polyvinyl acetate, polysiloxane, polymethyl vinyl siloxane, hydroxyethyl cellulose ati methyl cellulose.Awọn agbo ogun polymer adayeba gẹgẹbi gomu arabic, gomu ewa eṣú, karaya gomu, ati bẹbẹ lọ tun ni idapọ ti o dara pẹlu ojutu rẹ.Hydroxypropyl methylcellulose tun le dapọ pẹlu mannitol tabi awọn esters sorbitol ti stearic acid tabi palmitic acid, ati pe o tun le dapọ pẹlu glycerin, sorbitol ati mannitol.Awọn agbo ogun wọnyi le ṣee lo bi hydroxypropyl methylcellulose.Cellulose-orisun plasticizer.
5. Insolubility ati omi solubility ti hydroxypropyl methylcellulose
Awọn ethers cellulose ti omi ti a ko le sọ di ti hydroxypropyl methylcellulose le jẹ asopọ-dada pẹlu awọn aldehydes, ati awọn ethers ti omi-omi wọnyi ti wa ni iponju ninu ojutu ati ki o di insoluble ninu omi.Awọn aldehydes ti o jẹ ki hydroxypropyl methylcellulose insoluble pẹlu formaldehyde, glyoxal, succinaldehyde, adipaldehyde, bbl Nigbati o ba nlo formaldehyde, akiyesi pataki yẹ ki o san si iye pH ti ojutu, laarin eyiti glioxal ṣe yarayara.Nitorinaa, glycoxal ni a lo nigbagbogbo bi aṣoju ọna asopọ ni iṣelọpọ ile-iṣẹ.Awọn iwọn lilo ti iru iru ti crosslinking oluranlowo ni ojutu ni 0.2% ~ 10% ti awọn ether ibi-, pelu 7% ~ 10%, ati 3.3% ~ 6% ni o dara julọ fun glioxal.Iwọn otutu itọju gbogbogbo jẹ 0 ~ 30 ℃, ati pe akoko jẹ 1 ~ 120min.Idahun sisopọ agbelebu nilo lati ṣe labẹ awọn ipo ekikan.Ni gbogbogbo, inorganic lagbara acid tabi Organic carboxylic acid ti wa ni afikun si ojutu lati ṣatunṣe pH ti ojutu si nipa 2 ~ 6, ni pataki laarin 4 ~ 6, ati lẹhinna a ṣafikun aldehydes lati ṣe iṣesi ọna asopọ agbelebu..Awọn acids ti a lo pẹlu hydrochloric acid, sulfuric acid, phosphoric acid, formic acid, acetic acid, hydroxyacetic acid, succinic acid tabi citric acid, laarin eyiti formic acid tabi acetic acid dara, ati formic acid jẹ eyiti o dara julọ.Awọn acid ati aldehyde tun le ṣe afikun ni igbakanna lati gba ojutu laaye lati ṣe agbelebu ni ibiti pH ti o fẹ.Idahun yii ni a lo nigbagbogbo ni ilana itọju ikẹhin ni ilana igbaradi ti awọn ethers cellulose.Lẹhin ti ether cellulose jẹ insolubilized, o rọrun lati wẹ ati sọ di mimọ pẹlu omi ni 20 ~ 25 ° C.Nigbati ọja ba wa ni lilo, ohun elo ipilẹ le ṣe afikun si ojutu ọja lati ṣatunṣe pH ti ojutu lati jẹ ipilẹ, ati pe ọja naa yoo tu ni ojutu ni kiakia.Ọna yii tun wulo fun ojutu ether cellulose ti a ṣe sinu fiimu kan lẹhinna fiimu naa ti ni ilọsiwaju lati jẹ ki o jẹ fiimu ti a ko le yanju.
6. Hydroxypropyl methylcellulose jẹ sooro si awọn enzymu
Hydroxypropyl methylcellulose jẹ sooro si awọn enzymu.Ni imọran, awọn itọsẹ cellulose, gẹgẹ bi ẹgbẹ anhydroglucose kọọkan, ni ẹgbẹ aropo ti o ni asopọ ṣinṣin, eyiti ko rọrun lati ni akoran nipasẹ awọn microorganisms, ṣugbọn ni otitọ ọja ti o pari Nigbati iye iyipada ba kọja 1, yoo tun jẹ ibajẹ nipasẹ awọn ensaemusi, eyi ti o tumọ si pe iwọn iyipada ti ẹgbẹ kọọkan lori pq cellulose ko ni aṣọ ti o to, ati pe awọn microorganisms le parẹ nitosi awọn ẹgbẹ anhydroglucose ti ko rọpo lati ṣẹda awọn suga., eyi ti o gba bi awọn eroja fun awọn microorganisms.Nitorinaa, ti iwọn aropo etherification ti cellulose ba pọ si, resistance si ogbara enzymatic ti ether cellulose tun jẹ ilọsiwaju.O royin pe iki iyokù ti hydroxypropyl methylcellulose (DS=1.9) jẹ 13.2%, methylcellulose (DS=1.83) jẹ 7.3%, ati methylcellulose (DS=1.66) jẹ 3.8%, ati hydroxyethyl cellulose jẹ 1.7%.O le rii pe agbara egboogi-enzyme ti hydroxypropyl methylcellulose lagbara.Nitorinaa, resistance enzymu ti o dara julọ ti hydroxypropyl methylcellulose, ni idapo pẹlu itọka ti o dara, ti o nipọn ati awọn ohun-ini iṣelọpọ fiimu, ni gbogbogbo ni a lo ninu awọn ohun elo emulsion omi, ati bẹbẹ lọ, ati ni gbogbogbo ko nilo afikun awọn olutọju.Bibẹẹkọ, fun ibi ipamọ igba pipẹ ti ojutu tabi ibajẹ ti o ṣeeṣe ti ita gbangba, awọn ohun-itọju le ṣe afikun bi iṣọra, ati yiyan le ṣe ipinnu ni ibamu si awọn ibeere ikẹhin ti ojutu.Phenylmercuric acetate ati manganese fluorosilicate jẹ awọn olutọju ti o munadoko, ṣugbọn wọn ni Majele mejeeji, akiyesi gbọdọ wa ni san si iṣẹ naa, ati pe iwọn lilo jẹ gbogbo 1 ~ 5mg ti phenylmercuric acetate fun lita ti ojutu.
7. Awọn ohun-ini ti fiimu hydroxypropyl methylcellulose
Iṣiṣẹ ti fiimu hydroxypropyl methylcellulose Hydroxypropyl methylcellulose ni awọn ohun-ini iṣelọpọ fiimu ti o dara julọ, ati pe ojutu olomi rẹ tabi ojutu olomi Organic jẹ ti a bo lori awo gilasi kan, ati pe o di alailagbara ati sihin lẹhin gbigbe.Ati fiimu lile.O ni resistance ọrinrin to dara ati pe o wa ni ri to ni awọn iwọn otutu giga.Fun apẹẹrẹ, fifi pilasitik hygroscopic le ṣe alekun elongation ati irọrun rẹ.Lati mu irọrun dara si, awọn ṣiṣu ṣiṣu bi glycerin ati sorbitol ni o dara julọ.Idojukọ ojutu gbogbogbo jẹ 2% ~ 3%, ati iye ṣiṣu jẹ 10% ~ 20% ti ether cellulose.Ti akoonu ti ṣiṣu ṣiṣu ba ga ju, iṣẹlẹ isunmi ti gbigbẹ colloid yoo waye labẹ ọriniinitutu giga.Agbara fifẹ ti fiimu pẹlu ṣiṣu ṣiṣu ti a fi kun jẹ tobi pupọ ju pe laisi ṣiṣu, ati pe o pọ si pẹlu ilosoke iye ti a fi kun.Bi fun hygroscopicity ti fiimu naa, o tun pọ si pẹlu ilosoke ti iye ṣiṣu ṣiṣu.
Akoko ifiweranṣẹ: Oṣu Kẹwa-13-2022