I-Cellulose ether (CE) yiklasi ye-derivatives efunyenwe ngokuguqulwa kweekhemikhali i-cellulose. I-Cellulose iyona nxalenye ephambili yeendonga zeeseli zesityalo, kwaye i-cellulose ethers luluhlu lweepolymers eziveliswa yi-etherification yamaqela athile e-hydroxyl (-OH) kwi-cellulose. Zisetyenziswa kakhulu kwiinkalo ezininzi ezifana nezixhobo zokwakha, amayeza, ukutya, izithambiso, njl.njl., kwaye zisetyenziswa ngokubanzi kumashishini ahlukeneyo ngenxa yeempawu zabo ezizodwa kunye neekhemikhali kunye nokuguquguquka.
1. Ukuhlelwa kwee-ether ze-cellulose
I-cellulose ethers inokwahlulwa ibe ziindidi ezahlukeneyo ngokweentlobo zezinto ezibambeleyo kwisakhiwo sekhemikhali. Olona hlelo luqhelekileyo lusekwe kumahluko kwizinto ezibambeleyo. Ii-ether ze-cellulose eziqhelekileyo zezi zilandelayo:
I-Methyl cellulose (MC)
I-Methyl cellulose iveliswa ngokutshintsha indawo ye-hydroxyl ye-cellulose molekyuli kunye ne-methyl (-CH₃). Inokuqina okulungileyo, ukubunjwa kwefilimu kunye nokudibanisa kwaye isetyenziswa ngokuqhelekileyo kwizinto zokwakha, iingubo, amayeza kunye namashishini okutya.
IHydroxypropyl methylcellulose (HPMC)
I-Hydroxypropyl methylcellulose yi-ether ye-cellulose eqhelekileyo, esetyenziswa ngokubanzi kwizinto zokwakha, amayeza, iikhemikhali zemihla ngemihla kunye neendawo zokutya ngenxa yokunyibilika kwamanzi okungcono kunye nokuzinza kweekhemikhali. I-HPMC yi-ether ye-cellulose ye-nonionic eneempawu zokugcinwa kwamanzi, ukuqina kunye nokuzinza.
Carboxymethyl cellulose (CMC)
I-Carboxymethyl cellulose yi-anionic cellulose ether eyenziwa ngokuzisa amaqela e-carboxymethyl (-CH₂COOH) kwiimolekyuli ze-cellulose. I-CMC inonyibiliko olugqwesileyo lwamanzi kwaye isoloko isetyenziswa njenge-thickener, stabilizer kunye ne-arhente yokuxhoma. Idlala indima ebalulekileyo ekutyeni, kumayeza nakwizithambiso.
I-Ethyl cellulose (EC)
I-Ethyl cellulose ifunyenwe ngokutshintsha iqela le-hydroxyl kwi-cellulose kunye ne-ethyl (-CH₂CH₃). Ine-hydrophobicity elungileyo kwaye ihlala isetyenziswa njenge-ejenti yokugquma ifilimu kunye nezinto ezilawulwayo zokukhululwa kwishishini lamayeza.
2. Iimpawu zomzimba kunye neekhemikhali ze-cellulose ethers
Iimpawu ezibonakalayo kunye neekhemikhali ze-cellulose ethers zihambelana ngokusondeleyo kwizinto ezifana nodidi lwe-cellulose ether, uhlobo lwe-substitute kunye neqondo lokutshintshwa. Iimpawu zayo eziphambili ziquka ezi zilandelayo:
Ukunyibilika kwamanzi kunye nokunyibilika
Uninzi lwee-ether ze-cellulose zinokunyibilika kakuhle kwamanzi kwaye zinokunyibilika kumanzi abandayo okanye ashushu ukwenza isisombululo se-colloidal esicacileyo. Ngokomzekelo, i-HPMC, i-CMC, njl njl. inokuchithwa ngokukhawuleza emanzini ukwenza isisombululo esiphezulu se-viscosity, esisetyenziswa ngokubanzi kwiimeko zesicelo kunye neemfuno zokusebenza ezifana nokuqina, ukumiswa, kunye nokubunjwa kwefilimu.
Ukuqina kunye neempawu zokwenza ifilimu
I-cellulose ethers ineepropathi ezigqwesileyo zokujiya kwaye inokunyusa ngokufanelekileyo i-viscosity yezisombululo ezinamanzi. Umzekelo, ukongeza i-HPMC kwizinto zokwakha kunokuphucula iplastiki kunye nokusebenza kodaka kunye nokuphucula iipropati ezichasayo. Ngelo xesha, i-cellulose ethers ineepropati ezintle zokwenza ifilimu kwaye inokwenza ifilimu yokukhusela ifanayo ebusweni bezinto, ngoko ke isetyenziswe ngokubanzi kwiingubo kunye neengubo zeziyobisi.
Ukugcinwa kwamanzi kunye nokuzinza
I-cellulose ethers nayo inomthamo omhle wokugcina amanzi, ngakumbi kwintsimi yezinto zokwakha. I-cellulose ethers isoloko isetyenziselwa ukuphucula ukugcinwa kwamanzi kwi-sement mortar, ukunciphisa ukwenzeka kweentanda zodaka, kunye nokwandisa ubomi benkonzo yodaka. Kwintsimi yokutya, i-CMC ikwasetyenziswa njenge-humectant ukulibazisa ukomiswa kokutya.
Uzinzo lwekhemikhali
I-cellulose ethers ibonisa ukuzinza okulungileyo kweekhemikhali kwi-asidi, i-alkali kunye ne-electrolyte isisombululo, kwaye inokugcina isakhiwo sabo kunye nokusebenza kwiindawo ezahlukeneyo zeekhemikhali eziyinkimbinkimbi. Oku kuvumela ukuba zisetyenziswe kumashishini ahlukeneyo ngaphandle kokuphazamiseka kwezinye iikhemikhali.
3. Inkqubo yokuvelisa i-cellulose ether
Imveliso ye-cellulose ether ilungiswa ikakhulu yi-etherification reaction ye-cellulose yendalo. Amanyathelo enkqubo esisiseko abandakanya unyango lwe-alkalization ye-cellulose, ukuphendula kwe-etherification, ukuhlanjululwa, njl.
Unyango lwe-alkalization
Okokuqala, i-cellulose yendalo (efana nomqhaphu, iinkuni, njl. njl.) i-alkali ukuguqula inxalenye ye-hydroxyl kwi-cellulose ibe yityuwa esebenzayo kakhulu yotywala.
Ukusabela kwe-Etherification
I-cellulose emva kwe-alkalization iphendula kunye ne-etherifying agent (efana ne-methyl chloride, i-propylene oxide, njl.) ukuvelisa i-cellulose ether. Ngokuxhomekeke kwiimeko zokusabela, iintlobo ezahlukeneyo ze-cellulose ethers zinokufumaneka.
Ukuhlanjululwa kunye nokomisa
I-ether ye-cellulose eyenziwa yi-reaction iyahlanjululwa, ihlanjwe kwaye yomiswe ukuze ifumane umgubo okanye imveliso yegranular. Ubunyulu kunye neempawu ezibonakalayo zemveliso yokugqibela zinokulawulwa ngeteknoloji yokucubungula elandelayo.
4. Iinkalo zokusetyenziswa kwe-cellulose ether
Ngenxa yeempawu ezizodwa kunye neekhemikhali ze-cellulose ethers, zisetyenziswa ngokubanzi kumashishini amaninzi. Imihlaba yesicelo engundoqo yile ilandelayo:
Izinto zokwakha
Kwintsimi yezinto zokwakha, ii-cellulose ethers zisetyenziswa kakhulu njengezinto ezityebisayo kunye neearhente zokugcina amanzi kudaka lwesamente kunye neemveliso ezisekelwe kwigypsum. I-cellulose ethers efana ne-HPMC kunye ne-MC inokuphucula ukusebenza kokwakhiwa kodaka, ukunciphisa ukulahleka kwamanzi, kwaye ngaloo ndlela ikhulise ukubambelela kunye nokuxhathisa ukuqhekeka.
Iyeza
Kumashishini amayeza, i-cellulose ethers isetyenziswa ngokubanzi njengee-agent zokugquma kumachiza, i-adhesives for tablets, kunye nezixhobo ezikhutshwayo ezilawulwayo. Umzekelo, i-HPMC isoloko isetyenziselwa ukulungisa ifilimu yokugquma ifilimu kwaye inesiphumo esihle esilawulwayo sokukhululwa.
Ukutya
I-CMC isoloko isetyenziswa njenge-thickener, emulsifier, kunye ne-stabilizer kushishino lokutya. Isetyenziswa kakhulu kwiziselo, iimveliso zobisi, kunye nezinto ezibhakiweyo, kwaye inokuphucula incasa kunye neempawu zokuthambisa zokutya.
Izithambiso kunye neekhemikhali zemihla ngemihla
I-cellulose ethers isetyenziswa njenge-thickeners kunye ne-emulsifiers kunye ne-stabilizers kwi-cosmetics kunye neekhemikhali zemihla ngemihla, ezinokubonelela ngokuhambelana nokuhambelana kakuhle. Umzekelo, i-HPMC isoloko isetyenziswa kwiimveliso ezifana nentlama yamazinyo kunye neshampu ukubanika i-viscous imvakalelo kunye nesiphumo esizinzileyo sokunqunyanyiswa.
Iingubo
Kwishishini lokugquma, ii-cellulose ethers zisetyenziswa njenge-thickeners, ii-filmforms, kunye ne-suspending agents, ezinokuthi ziphucule ukusebenza kolwakhiwo lwee-coatings, ziphucule umgangatho, kwaye zibonelele ngomgangatho wefilimu yepeyinti elungileyo.
5. Uphuhliso lwexesha elizayo lwe-cellulose ethers
Ngokunyuka kwemfuno yokukhuselwa kwendalo, i-cellulose ether, njenge-derivative yemithombo yendalo ehlaziyiweyo, inethemba elibanzi lophuhliso. I-biodegradability yayo, ukuvuselelwa kunye nokuguquguquka kwenza ukuba kulindeleke ukuba kusetyenziswe ngokubanzi kwiindawo zezixhobo eziluhlaza, izinto ezinokonakala kunye nezixhobo ezihlakaniphile kwixesha elizayo. Ukongeza, i-cellulose ether nayo inophando olongezelelweyo kunye namandla ophuhliso kwiindawo eziphezulu zexabiso elongezelelweyo ezifana nobunjineli be-biomedical kunye nezixhobo eziphambili.
Njengemveliso ebalulekileyo yeekhemikhali, i-cellulose ether inoluhlu olubanzi lwexabiso lesicelo. Ngokutyeba kwayo okugqwesileyo, ukugcinwa kwamanzi, ukwenza ifilim kunye nokuzinza okuhle kweekhemikhali, idlala indima engenakuthathelwa indawo kwiindawo ezininzi ezinjengokwakha, amayeza, kunye nokutya. Kwixesha elizayo, kunye nokuqhubela phambili kweteknoloji kunye nokukhuthazwa kweengcamango zokukhusela indalo, amathuba okusetyenziswa kwe-cellulose ether aya kuba banzi kwaye enze igalelo elikhulu ekukhuthazeni uphuhliso oluzinzileyo lwamashishini ahlukeneyo.
Ixesha lokuposa: Sep-24-2024