Lekwasị anya na cellulose ethers

Olee mmetụta okpomọkụ nwere na viscosity nke HPMC aqueous ngwọta?

Hydroxypropyl Methylcellulose (HPMC) bụ ihe dị mkpa na-edozi mmiri nke a na-ejikarị eme ihe na ọgwụ, nri, mkpuchi, ihe ụlọ na ubi ndị ọzọ. Ngwọta viscosity nke HPMC bụ isi ihe na-emetụta arụmọrụ ya na ngwa ya, yana ọnọdụ okpomọkụ nwere mmetụta dị ukwuu na viscosity nke ngwọta mmiri HPMC.

1. Viscosity e ji mara nke HPMC ngwọta
HPMC bụ ihe eji eme ihe na-emepụta ihe na-ekpo ọkụ na-ekpo ọkụ. Mgbe HPMC gbazere n'ime mmiri, ihe ngwọta aqueous a kpụrụ na-egosiputa àgwà mmiri na-abụghị nke Newtonian, ya bụ, viscosity ngwọta na-agbanwe na mgbanwe na ọnụ ọgụgụ shear. Na okpomọkụ nkịtị, ihe ngwọta HPMC na-emekarị ka mmiri pseudoplastic, ya bụ, ha nwere viscosity dị elu na ọnụ ọgụgụ dị ala nke shear, na viscosity na-ebelata ka ọnụ ọgụgụ nke shear na-abawanye.

2. Mmetụta nke okpomọkụ na viscosity nke HPMC ngwọta
Mgbanwe okpomọkụ nwere usoro mmetụta abụọ bụ isi na viscosity nke ngwọta mmiri nke HPMC: mmụba okpomọkụ nke agbụ molecular na mgbanwe na mmekọrịta ngwọta.

(1) Thermal ngagharị nke molekụla agbụ na-abawanye
Mgbe okpomọkụ na-abawanye, mmegharị okpomọkụ nke eriri molecular HPMC na-abawanye, nke na-eme ka njikọ hydrogen na ndị agha van der Waals dị n'etiti ụmụ irighiri ihe na-ada mbà na mmiri nke ngwọta na-abawanye. Viscosity nke ngwọta na-ebelata n'ihi mbelata ntachi obi na njikọ anụ ahụ n'etiti agbụ molecular. Ya mere, HPMC aqueous ngwọta na-egosipụta ala viscosity na elu okpomọkụ.

(2) Mgbanwe na mmekọrịta ngwọta
Mgbanwe okpomọkụ nwere ike imetụta solubility nke mkpụrụ ndụ HPMC na mmiri. HPMC bụ polymer nwere ihe ọkụ ọkụ, na solubility ya na mmiri na-agbanwe nke ukwuu na okpomọkụ. N'oge okpomọkụ dị ala, ndị otu hydrophilic dị na agbụ molekul HPMC na-etolite njikọ hydrogen kwụsiri ike na ụmụ irighiri mmiri, si otú a na-ejigide ezigbo solubility na nnukwu viscosity. Otú ọ dị, mgbe okpomọkụ na-ebili ruo n'ókè ụfọdụ, a na-eme ka mmekọrịta hydrophobic dị n'etiti eriri mkpụrụ ndụ HPMC, na-eduga n'ịmepụta usoro netwọk akụkụ atọ ma ọ bụ gelation na ngwọta, na-eme ka viscosity ngwọta na-abawanye na mberede n'okpuru ọnọdụ ụfọdụ. A na-akpọ ihe a na-akpọ Ọ bụ ihe omume "gel thermal".

3. Nleba anya nke okpomọkụ na HPMC ngwọta viscosity
Nnyocha nnwale egosila na n'ime oke okpomọkụ a na-ahụkarị (dịka ọmụmaatụ, 20°C ruo 40°C), viscosity nke mmiri mmiri HPMC ji nwayọọ nwayọọ na-ebelata na okpomọkụ na-abawanye. Nke a bụ n'ihi na okpomọkụ dị elu na-abawanye ike ike nke ụdọ molekụla ma belata mmekọrịta intermolecular, si otú a na-ebelata esemokwu dị n'ime nke ngwọta. Otú ọ dị, mgbe okpomọkụ na-aga n'ihu na-abawanye ruo ebe okpomọkụ nke HPMC (na-emekarị n'etiti 60 ° C na 90 ° C, dabere na ogo nke nnọchi na ịdị arọ nke HPMC), viscosity ngwọta na-abawanye na mberede. Ihe omume nke a metụtara njikọ na nchikota nke agbụ molekul HPMC.

4. Mmekọrịta dị n'etiti okpomọkụ na HPMC structural parameters
The ngwọta viscosity nke HPMC bụghị nanị na-emetụta okpomọkụ, ma na-akpachi anya na ya molekụla Ọdịdị. Dịka ọmụmaatụ, ogo ngbanwe (ya bụ, ọdịnaya nke hydroxypropyl na methyl substituents) na ịdị arọ molekul nke HPMC nwere mmetụta dị ukwuu na omume jel ya. HPMC nwere ogo dị elu nke nnọchi na-edobe viscosity dị ala na oke okpomọkụ ka ukwuu n'ihi otu hydrophilic ya karịa, ebe HPMC nwere obere ngbanwe nwere ike ịbụ gels thermal. Na mgbakwunye, ihe ngwọta HPMC nwere ibu arọ dị elu nwere ike ịbawanye na viscosity na okpomọkụ dị elu.

5. Nleba anya ngwa ọrụ na nke bara uru
Na ngwa bara uru, ekwesịrị ịhọrọ ụdị HPMC kwesịrị ekwesị dabere na ọnọdụ okpomọkụ akọwapụtara. Dịka ọmụmaatụ, na gburugburu ebe okpomọkụ dị elu, HPMC nwere nguzogide okpomọkụ dị elu kwesịrị ịhọrọ iji zere gelation thermal. N'okpuru ọnọdụ okpomọkụ dị ala, ekwesịrị ịtụle solubility na nkwụsi ike viscosity nke HPMC.

Mmetụta nke okpomọkụ na viscosity nke HPMC aqueous ngwọta nwere mkpa bara uru bara uru. N'ebe a na-emepụta ọgwụ, a na-ejikarị HPMC eme ihe dị ka ihe ntọhapụ na-adịgide adịgide maka nkwadebe ọgwụ, na njirimara viscosity ya na-emetụta ọnụego ntọhapụ ọgwụ ozugbo. N'ime ụlọ ọrụ nri, a na-eji HPMC emeziwanye ọdịdị na nkwụsi ike nke ngwaahịa, na ịdabere na ọnọdụ okpomọkụ nke viscosity ngwọta ya kwesịrị ka edozi ya dịka nhazi nhazi. N'ihe owuwu ihe, a na-eji HPMC eme ihe dị ka onye na-ejigide mmiri na mmiri, na njirimara viscosity ya na-emetụta arụmọrụ ihe owuwu na ike ihe.

Mmetụta nke okpomọkụ na viscosity nke HPMC aqueous ngwọta bụ usoro mgbagwoju anya na-agụnye mmegharị okpomọkụ nke yinye molecular, mmekọrịta ngwọta, na ihe nhazi nke polymer. N'ozuzu, viscosity nke HPMC aqueous ngwọta n'ozuzu ebelata na-amụba okpomọkụ, ma na ụfọdụ okpomọkụ ranges, thermal gelation nwere ike ime. Ịghọta njirimara a nwere mkpa nduzi dị mkpa maka ngwa bara uru na njikarịcha usoro nke HPMC.


Oge nzipu: Jul-10-2024
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