I-Cellulose ether ludidi olubalulekileyo lwee-polymer compounds, ezisetyenziswa kakhulu ekwakheni, kumayeza, ekutyeni nakwezinye iindawo. Phakathi kwazo, i-HPMC (hydroxypropyl methylcellulose), i-MC (methylcellulose), i-HEC (hydroxyethyl cellulose) kunye ne-CMC (carboxymethyl cellulose) zii-cellulose ethers ezine eziqhelekileyo.
I-Methyl cellulose (MC):
I-MC iyanyibilika emanzini abandayo kwaye kunzima ukuyinyibilikisa emanzini ashushu. Isisombululo samanzi sizinzile kakhulu kuluhlu lwe-pH=3~12, sihambelana kakuhle, kwaye singaxutywa neendidi ezahlukeneyo ze-surfactants ezifana ne-starch kunye ne-guar gum. Xa ubushushu bufikelela kubushushu be-gelation, i-gelation iyenzeka.
Ukugcinwa kwamanzi kwe-MC kuxhomekeke kubungakanani bayo bokongeza, ukuxinana, ubunono beentwana kunye nesantya sokunyibilika. Ngokubanzi, izinga lokugcina amanzi liphezulu xa inani lokongeza likhulu, iintwana zilungile kwaye ubunono buphezulu. Phakathi kwazo, ubungakanani bokongeza bunempembelelo enkulu kwizinga lokugcinwa kwamanzi, kwaye inqanaba le-viscosity alilingani nesantya sokugcinwa kwamanzi. Izinga lokunyibilika lixhomekeke kakhulu kwinqanaba lokuguqulwa komphezulu kunye nobunono beentwana zeentwana ze-cellulose.
Utshintsho lobushushu luya kuyichaphazela kakhulu indlela amanzi agcinwa ngayo kwi-MC. Ngokubanzi, xa ubushushu buphezulu, kokukhona amanzi egcinwa ngayo. Ukuba ubushushu be-mortar budlula i-40°C, indlela amanzi agcinwa ngayo kwi-MC iya kuncipha kakhulu, nto leyo echaphazela kakhulu indlela yokwakha i-mortar.
I-MC inempembelelo enkulu ekusebenzeni kolwakhiwo kunye nokunamathela kwe-mortar. Apha, "ukunamathela" kubhekisa ekunamatheleni phakathi kwezixhobo zokwakha zomsebenzi kunye ne-substrate yodonga, oko kukuthi, ukumelana nokucheba kwe-mortar. Okukhona ukunamathela kukhulu, kokukhona ukumelana nokucheba kwe-mortar kukhulu, kokukhona amandla afunekayo ngumsebenzi ngexesha lokusetyenziswa, kunye nokusebenza kakubi kolwakhiwo lwe-mortar. Ukunamathela kwe-MC kukwinqanaba eliphakathi phakathi kweemveliso ze-cellulose ether.
I-Hydroxypropyl methylcellulose (HPMC):
I-HPMC inyibilika lula emanzini, kodwa kunokuba nzima ukuyinyibilikisa emanzini ashushu. Nangona kunjalo, ubushushu bayo bokunyibilika emanzini ashushu buphezulu kakhulu kunobo be-MC, kwaye ukunyibilika kwayo emanzini abandayo kubhetele kunobo be-MC.
Ubunzima be-HPMC bunxulumene nobunzima be-molecular, kwaye ubuninzi be-viscosity buphezulu xa ubunzima be-molecular bukhulu. Ubushushu buchaphazela nobunzima bayo, kwaye ubuninzi be-viscosity buyancipha njengoko ubushushu busanda, kodwa ubushushu apho ubuninzi be-viscosity buncipha khona buphantsi kunobo be-MC. Isisombululo sayo sizinzile kubushushu begumbi.
Ukugcinwa kwamanzi kwe-HPMC kuxhomekeke kubungakanani bokongeza kunye nokuxinana, njl. Izinga lokugcinwa kwamanzi kubungakanani obufanayo bokongeza liphezulu kunelo le-MC.
I-HPMC izinzile kwiiasidi kunye neealkali, kwaye isisombululo sayo samanzi sizinzile kakhulu kuluhlu lwe-pH oluyi-2 ~ 12. I-caustic soda kunye namanzi ekalika azinampembelelo ingako ekusebenzeni kwayo, kodwa i-alkali inokukhawulezisa izinga layo lokunyibilika kwaye yonyuse i-viscosity. I-HPMC izinzile kwiityuwa eziqhelekileyo, kodwa xa uxinzelelo lwesisombululo setyuwa luphezulu, i-viscosity yesisombululo se-HPMC idla ngokwanda.
I-HPMC ingaxutywa neekhompawundi zepolymer ezinyibilikayo emanzini ukuze zenze isisombululo esifanayo nesinoburhabaxa, esifana ne-polyvinyl alcohol, i-starch ether, i-vegetable gum, njl.njl.
I-HPMC inokumelana ngcono nee-enzyme kune-MC, kwaye isisombululo sayo asichaphazeleki lula kukubola kwee-enzyme kune-MC. I-HPMC inamathela ngcono kwi-mortar kune-MC.
I-Hydroxyethyl cellulose (HEC):
I-HEC iyanyibilika emanzini abandayo kwaye kunzima ukuyinyibilikisa emanzini ashushu. Isisombululo sizinzile kubushushu obuphezulu kwaye asinazo iimpawu zejeli. Ingasetyenziswa kwi-mortar ixesha elide kubushushu obuphezulu, kodwa ukugcinwa kwamanzi kwayo kuphantsi kune-MC.
I-HEC izinzile kwii-asidi eziqhelekileyo kunye nee-alkali, i-alkali inokukhawulezisa ukunyibilika kwayo kwaye inyuse kancinci i-viscosity, kwaye ukusasazeka kwayo emanzini kungaphantsi kancinci kune-MC kunye ne-HPMC.
I-HEC isebenza kakuhle ekuxhomeni i-mortar, kodwa isamente ithatha ixesha elide ukuyigcina ingasebenzi.
I-HEC eveliswa ngamanye amashishini asekhaya ayisebenzi kakuhle kune-MC ngenxa yokuba inamanzi amaninzi kunye nomxholo wothuthu.
I-Carboxymethyl cellulose (CMC):
I-CMC yi-ionic cellulose ether elungiselelwe ngoluhlu lweendlela zonyango emva kokuba imicu yendalo (efana nomqhaphu) iphathwe nge-alkali kwaye i-chloroacetic acid isetyenziswa njenge-etherifying agent. Ubungakanani bokutshintshwa ngokubanzi buphakathi kwe-0.4 kunye ne-1.4, kwaye ukusebenza kwayo kuchaphazeleka kakhulu bubungakanani bokutshintshwa.
I-CMC inefuthe lokuzinzisa ukuqina kunye nokuxutywa kwe-emulsification, kwaye ingasetyenziswa kwiziselo eziqulethe ioyile kunye neproteni ukuze idlale indima yokuzinzisa i-emulsification.
I-CMC inefuthe lokugcina amanzi. Kwiimveliso zenyama, isonka, iibhanisi eziphekiweyo kunye nokunye ukutya, inokudlala indima ekuphuculeni izicubu, kwaye ingenza amanzi angaguquguquki, inyuse isivuno semveliso, kwaye inyuse incasa.
I-CMC inefuthe le-gelling kwaye ingasetyenziselwa ukwenza ijeli kunye nejam.
I-CMC inokwenza ifilimu phezu kokutya, enefuthe elithile lokukhusela kwiziqhamo nemifuno kwaye yandise ubomi beshelufu beziqhamo nemifuno.
Ezi ethers ze-cellulose nganye ineempawu zayo ezizodwa kunye neendawo zokusetyenziswa. Ukukhethwa kweemveliso ezifanelekileyo kufuneka kumiselwe ngokweemfuno ezithile zokusetyenziswa kunye neemeko zokusingqongileyo.
Ixesha leposi: Okthobha-29-2024