Cellulose ether bụ klas dị mkpa nke ogige polymer, nke a na-ejikarị arụ ọrụ, ọgwụ, nri na ubi ndị ọzọ. N'ime ha, HPMC (hydroxypropyl methylcellulose), MC (methylcellulose), HEC (hydroxyethyl cellulose) na CMC (carboxymethyl cellulose) bụ anọ nkịtị cellulose ethers.
Methyl cellulose (MC):
MC na-agbaze na mmiri oyi ma sie ike igbari na mmiri ọkụ. Ngwọta mmiri na-esiwanye ike na pH = 3 ~ 12, nwere ezigbo ndakọrịta, enwere ike ịgwakọta ya na ụdị surfactants dị iche iche dị ka starch na guar gum. Mgbe okpomọkụ na-erute okpomọkụ gelation, gelation na-eme.
Njide mmiri nke MC dabere na ego mgbakwunye ya, viscosity, ịdị mma nke urughuru na ọnụego mgbasa. N'ozuzu, ọnụ ọgụgụ njide mmiri dị elu mgbe ego mgbakwunye dị ukwuu, ihe ndị ahụ dị mma na viscosity dị elu. N'ime ha, ego mgbakwunye na-enwe mmetụta dị ukwuu na njide mmiri, na ọkwa viscosity adịghị adabere na njide mmiri. The mgbasa ọnụego tumadi na-adabere n'elu mgbanwe ogo na urughuru fineness nke cellulose ahụ.
Mgbanwe okpomọkụ ga-emetụta oke mmiri nke MC. N'ozuzu, ka okpomọkụ dị elu, na-akawanye njọ njigide mmiri. Ọ bụrụ na okpomọkụ nke ngwa agha gafere 40 Celsius C, njide mmiri nke MC ga-ebelata nke ukwuu, na-emetụta oke arụ ọrụ nke ngwa agha ahụ.
MC nwere mmetụta dị ukwuu na arụ ọrụ ihe owuwu na nrapado nke ngwa agha ahụ. N'ebe a, "adhesion" na-ezo aka nchikota n'etiti ngwá ọrụ onye ọrụ na-arụ ọrụ na mgbidi mgbidi, ya bụ, nkwụsị nke ngwa agha. Ka ọ dị ukwuu na adhesion, nke ukwuu na-eguzogide ọgwụ mgbochi nke ngwa agha ahụ, ka ike dị ukwuu nke onye ọrụ ahụ chọrọ n'oge a na-eji ya eme ihe, na arụ ọrụ na-adịghị mma nke ngwa agha ahụ. Adhesion nke MC dị n'ogo ọkara n'etiti ngwaahịa ether cellulose.
Hydroxypropyl methylcellulose (HPMC):
HPMC na-adị mfe mgbaze na mmiri, mana ọ nwere ike isi ike igbari na mmiri ọkụ. Otú ọ dị, okpomọkụ gelation ya na mmiri ọkụ dị elu karịa nke MC, na solubility ya na mmiri oyi dịkwa mma karịa nke MC.
The viscosity nke HPMC metụtara molekụla arọ, na viscosity dị elu mgbe molekụla arọ bụ nnukwu. Okpomọkụ na-emetụtakwa viscosity ya, na viscosity na-ebelata ka okpomọkụ na-abawanye, mana okpomọkụ nke viscosity ya na-ebelata dị ala karịa nke MC. Ihe ngwọta ya kwụsiri ike na ụlọ okpomọkụ.
Njide mmiri nke HPMC na-adabere na ntinye ego na viscosity, wdg. Ọnụego njide mmiri na otu ihe mgbakwunye dị elu karịa nke MC.
HPMC kwụsiri ike na acids na alkalis, na ngwọta mmiri ya kwụsiri ike na pH nke 2 ~ 12. Caustic soda na mmiri lime enweghị mmetụta dị nta na arụmọrụ ya, mana alkali nwere ike mee ka ọnụego mgbasa ya dịkwuo elu ma nwekwuo viscosity. HPMC kwụsiri ike na nnu n'ozuzu, mana mgbe ntinye nke ngwọta nnu dị elu, viscosity nke ngwọta HPMC na-abawanye.
Enwere ike ịgwakọta HPMC na ogige polymer mmiri soluble iji mepụta otu, ngwọta viscosity dị elu, dị ka mmanya polyvinyl, starch ether, chịngọm akwukwo nri, wdg.
HPMC nwere nguzogide enzyme dị mma karịa MC, na ngwọta ya adịghị mfe na mmebi enzymatic karịa MC. HPMC nwere mma mmachi na ngwa agha karịa MC.
Hydroxyethyl cellulose (HEC):
HEC na-agbaze na mmiri oyi ma sie ike igbari na mmiri ọkụ. Ngwọta ahụ kwụsiri ike na oke okpomọkụ ma ọ nweghị ihe gel. Enwere ike iji ya na ngwa agha ogologo oge na oke okpomọkụ, mana njide mmiri ya dị ala karịa MC.
HEC kwụsiri ike na acid n'ozuzu na alkalis, alkali nwere ike mee ka mgbasa ya dịkwuo elu ma na-abawanye viscosity, na dispersibility na mmiri dị ntakịrị karịa MC na HPMC.
HEC nwere arụmọrụ nkwusioru dị mma maka ngwa agha, mana ciment nwere ogologo oge nkwụghachi azụ.
HEC nke ụfọdụ ụlọ ọrụ na-emepụta na-arụ ọrụ dị ala karịa MC n'ihi nnukwu mmiri na ọdịnaya ash.
Carboxymethyl cellulose (CMC):
CMC bụ ionic cellulose ether nke a kwadebere site na usoro ọgwụgwọ mmeghachi omume mgbe ejiri alkali mesoo eriri eke (dị ka owu) na chloroacetic acid na-eji dị ka ihe na-eme ka etherifying. Ogo nnọchi anya na-adịkarị n'etiti 0.4 na 1.4, yana ogo nnọchi anya na-emetụta arụmọrụ ya nke ukwuu.
CMC nwere mmetụta nkwụsi ike na emulsification, enwere ike iji ya na mmanya nwere mmanụ na protein iji rụọ ọrụ nkwụsi ike emulsification.
CMC nwere mmetụta njigide mmiri. N'ime ngwaahịa anụ, achịcha, buns steamed na nri ndị ọzọ, ọ nwere ike ịrụ ọrụ na-emeziwanye anụ ahụ, ma nwee ike ime ka mmiri ghara ịdị na-agbanwe agbanwe, na-amụba mkpụrụ ngwaahịa, na-abawanye uto.
CMC nwere mmetụta gelling na enwere ike iji mee jelii na jam.
CMC nwere ike ịmepụta ihe nkiri n'elu nri, nke nwere mmetụta nchebe ụfọdụ na mkpụrụ osisi na akwụkwọ nri ma na-agbatị ndụ ndụ nke mkpụrụ osisi na akwụkwọ nri.
Ndị a cellulose ethers nke ọ bụla nwere ihe pụrụ iche nke ya na mpaghara ngwa. Nhọrọ nke ngwaahịa kwesịrị ekwesị kwesịrị ikpebi dịka ngwa ngwa chọrọ na ọnọdụ gburugburu ebe obibi.
Oge nzipu: Ọktoba 29-2024