Kini iyato laarin HPMC ati MC?

A:

MC jẹ methyl cellulose: ti wa ni refaini owu lẹhin alkali itọju, methane kiloraidi bi etherifying oluranlowo, nipasẹ kan lẹsẹsẹ ti aati lati ṣe cellulose ether.Ni gbogbogbo, iwọn aropo jẹ 1.6 ~ 2.0, ati solubility yatọ pẹlu iwọn aropo.Je ti nonionic cellulose ether.

(1) Idaduro omi ti methyl cellulose da lori iye afikun rẹ, iki, didara patiku ati oṣuwọn itusilẹ.Ni gbogbogbo ṣafikun iye nla, itanran kekere, iki, oṣuwọn idaduro omi jẹ giga.Iwọn awọn afikun ni ipa nla lori iwọn idaduro omi, ati pe iki ko ni ibamu si iwọn idaduro omi.Oṣuwọn itu ni pataki da lori iwọn iyipada oju ilẹ ati didara patiku ti awọn patikulu cellulose.Ninu awọn ethers cellulose pupọ ti o wa loke, methyl cellulose ati HPMC hydroxypropyl methyl cellulose iye idaduro omi jẹ ti o ga julọ.

(2) Methyl cellulose jẹ tiotuka ninu omi tutu, eyiti o ṣoro lati tu ninu omi gbona.Ojutu olomi rẹ jẹ iduroṣinṣin pupọ laarin pH = 3 ~ 12.O ni ibamu ti o dara pẹlu sitashi, guanidine gomu ati ọpọlọpọ awọn surfactants.Gelation waye nigbati iwọn otutu ba de iwọn otutu gelation.

(3) Iyipada ti iwọn otutu yoo ni ipa ni pataki ni oṣuwọn idaduro omi ti methyl cellulose.Ni gbogbogbo, iwọn otutu ti o ga julọ, buru si idaduro omi.Ti iwọn otutu ti amọ-lile ba kọja 40 ℃, idaduro omi ti methyl cellulose yoo buru pupọ, eyiti o ni ipa lori iṣelọpọ amọ.

(4) Methyl cellulose ni ipa ti o han gbangba lori iṣelọpọ ati ifaramọ ti amọ.“Adhesion” nibi n tọka si ifaramọ ti oṣiṣẹ ti o rilara laarin ọpa ati sobusitireti ogiri, eyun resistance rirẹ ti amọ.Adhesion jẹ nla, irẹrun resistance ti amọ jẹ nla, agbara ti awọn oṣiṣẹ nilo ninu ilana lilo tun tobi, ati ikole amọ-lile ko dara.Ninu awọn ọja ether cellulose, ifaramọ ti methyl cellulose wa ni ipele iwọntunwọnsi.

HPMC jẹ hydroxypropyl methyl cellulose: o jẹ ti owu ti a ti tunṣe lẹhin itọju alkali, pẹlu propylene oxide ati chloromethane gẹgẹbi oluranlowo etherifying, nipasẹ awọn aati ti o pọju ati ti a ṣe ti cellulose ti kii ṣe ionic ether.Iwọn aropo jẹ gbogbogbo 1.2 ~ 2.0.Awọn ohun-ini rẹ yatọ pẹlu ipin ti methoxy ati akoonu hydroxypropyl.

(1) HPMC hydroxypropyl methyl cellulose jẹ irọrun tiotuka ninu omi tutu, eyiti o ṣoro lati tu ninu omi gbona.Sibẹsibẹ, iwọn otutu gelation rẹ ninu omi gbona han gbangba ga ju ti methyl cellulose lọ.Solubility ti methyl cellulose ninu omi tutu tun ni ilọsiwaju pupọ.

(2) iki ti HPMC hydroxypropyl methyl cellulose jẹ ibatan si iwuwo molikula rẹ, ati pe iwuwo molikula ti o ga julọ, iki ti o ga julọ.Iwọn otutu tun ni ipa lori iki.Viscosity dinku bi iwọn otutu ti n pọ si.Ṣugbọn iki rẹ ga otutu ipa jẹ kekere ju ti methyl cellulose.Ojutu naa jẹ iduroṣinṣin nigbati o fipamọ ni iwọn otutu yara.

(3) HPMC hydroxypropyl methyl cellulose jẹ iduroṣinṣin si acid ati ipilẹ, ati pe ojutu olomi rẹ jẹ iduroṣinṣin pupọ ni ibiti pH = 2 ~ 12.Omi onisuga caustic ati omi orombo wewe ni ipa diẹ lori awọn ohun-ini rẹ, ṣugbọn alkali le mu iwọn itusilẹ rẹ pọ si ki o mu iki sii.HPMC hydroxypropyl methyl cellulose jẹ iduroṣinṣin si awọn iyọ gbogbogbo, ṣugbọn nigbati ifọkansi ti ojutu iyọ ba ga, iki ti HPMC hydroxypropyl methyl cellulose ojutu duro lati pọ si.

(4) Idaduro omi ti HPMC hydroxypropyl methyl cellulose da lori iwọn lilo rẹ ati iki, ati iye idaduro omi ti HPMC hydroxypropyl methyl cellulose jẹ ti o ga ju ti methyl cellulose lọ ni iwọn kanna.

(5) HPMC hydroxypropyl methyl cellulose ni a le dapọ pẹlu awọn agbo ogun polima-tiotuka omi lati di aṣọ ile, ojutu iki ti o ga julọ.Bii oti polyvinyl, sitashi ether, lẹ pọ Ewebe ati bẹbẹ lọ.

(6) Adhesion ti HPMC hydroxypropyl methyl cellulose si amọ ikole jẹ ti o ga ju ti methyl cellulose.

(7) HPMC hydroxypropyl methyl cellulose ni o ni dara henensiamu resistance ju methyl cellulose, ati awọn oniwe-ojutu henensiamu ibaje seese jẹ kekere ju ti methyl cellulose.