Hydroxypropylmethylcellulose

Kakaretso: e bitsoa HPMC, e tšoeu kapa e bosoeu bo bosoeu kapa phofo ea granular. Ho na le mefuta e mengata ea selulose mme e sebelisoa haholo, empa haholo-holo re ikopanya le bareki ba indasteri ea thepa ea ho haha ​​ea phofo e omileng. Selulose e tloaelehileng haholo e bua ka hypromellose.

Ts'ebetso ea tlhahiso: Lisebelisoa tse ka sehloohong tsa HPMC: k'hothone e hloekisitsoeng, methyl chloride, propylene oxide, lisebelisoa tse ling tse tala li kenyelletsa flake alkali, acid, toluene, isopropanol, joalo-joalo Tšoara cellulose e hloekisitsoeng ea k'hothone ka tharollo ea alkali ho 35-40 ℃ bakeng sa halofo ea hora, tobetsa, pshatla selulose, 'me u tsofala hantle ho 35 ℃, e le hore tekanyo e tloaelehileng ea polymerization ea se fumanoeng. alkali fiber e ka har'a mefuta e hlokahalang. Kenya likhoele tsa alkali ka har'a kettle ea etherification, eketsa propylene oxide le methyl chloride ka lehlakoreng le leng, 'me u be le etherify ho 50-80 °C bakeng sa lihora tse 5, ka khatello e phahameng ea hoo e ka bang 1.8 MPa. Ebe u eketsa palo e loketseng ea hydrochloric acid le oxalic acid metsing a chesang a 90 ° C ho hlatsoa thepa ho atolosa molumo. Dehydrate e nang le centrifuge. Hlatsoa ho fihlela u sa nke lehlakore, 'me ha mongobo oa thepa o le ka tlase ho 60%, o omise ka ho phalla ha moea o chesang ho 130 ° C ho ea tlase ho 5%. Mosebetsi: ho boloka metsi, ho teteana, anti-sag ea thixotropic, ho sebetsa ha moea, ho fokotsa maemo.

Ho boloka metsi: Ho boloka metsi ke thepa ea bohlokoa ka ho fetisisa ea cellulose ether! Ha ho etsoa seretse sa putty gypsum le lisebelisoa tse ling, kopo ea cellulose ether e bohlokoa. Ho boloka metsi a phahameng ho ka ama ka botlalo molora oa samente le calcium gypsum (ha motho a arabela ka botlalo, a na le matla a maholo). Tlas'a maemo a tšoanang, ho phahama ha viscosity ea cellulose ether, ho molemo ho boloka metsi (lekhalo le ka holimo ho 100,000 viscosity le fokotsehile); ha litekanyetso li phahame, ho boloka metsi ho betere, hangata palo e nyane ea cellulose ether e ka ntlafatsa haholo ts'ebetso ea seretse. Sekhahla sa ho boloka metsi, ha litaba li fihla boemong bo itseng, mokhoa oa ho eketsa sekhahla sa ho boloka metsi o fokotseha butle; sekhahla sa ho boloka metsi sa cellulose ether hangata sea fokotseha ha mocheso oa tikoloho o eketseha, empa li-ether tse ling tse phahameng tsa gel cellulose le tsona li na le ts'ebetso e ntle tlas'a maemo a phahameng a mocheso. Ho boloka metsi. The interdiffusion pakeng tsa limolek'hule tsa metsi le selulose ether molek'hule liketane etsa hore limolek'hule tsa metsi ho kena ka hare ho selulose ether macromolecular liketane le ho fumana matla a tlamang matla, ka tsela eo ho etsa metsi a mahala, entangling metsi, le ho ntlafatsa ho boloka metsi a samente slurry.

Thickening, thixotropic le anti-sag: e fana ka viscosity e babatsehang ho seretse se metsi! E ka eketsa haholo ho khomarela pakeng tsa seretse se metsi le lera la motheo, le ho ntlafatsa ts'ebetso e khahlanong le ho senyeha ha seretse. Phello e ntseng e eketseha ea li-cellulose ethers e boetse e eketsa ho hanyetsa ho hasana le homogeneity ea lisebelisoa tse sa tsoa tsoakoa, ho thibela ho senyeha ha lintho, ho arohana le ho tsoa mali. Phello e matla ea li-cellulose ethers linthong tse thehiloeng ho samente e tsoa ho viscosity ea litharollo tsa cellulose ether. Tlas'a maemo a ts'oanang, ho phahama ha viscosity ea cellulose ether, ho tla ba betere ho ntlafala ha viscosity ea thepa e fetotsoeng e thehiloeng ho samente, empa haeba viscosity e le kholo haholo, e tla ama ho phalla le ho sebetsa ha thepa (joalo ka trowel e khomarelang le batch. sekgohla). kgathetse). Seretse se ikemetseng le konkreite e ikemetseng e hlokang metsi a mangata e hloka viscosity e tlase ea cellulose ether. Ho phaella moo, phello e matla ea cellulose ether e tla eketsa tlhokahalo ea metsi ea thepa e thehiloeng ho samente le ho eketsa chai ea seretse. High viscosity cellulose ether aqueous solution e na le thixotropy e phahameng, eo hape e leng tšobotsi e kholo ea cellulose ether. Litharollo tsa metsi tsa cellulose ka kakaretso li na le thepa ea phallo ea pseudoplastic, e seng thixotropic ka tlase ho mocheso oa bona oa gel, empa thepa ea phallo ea Newtonian ka litheko tse tlase tsa ho kuta. Pseudoplasticity e eketseha ha boima ba limolek'hule bo eketseha kapa khatello ea cellulose ether. Li-gels tsa mohaho li thehoa ha mocheso o ntse o eketseha, 'me phallo e phahameng ea thixotropic e etsahala. Li-cellulose ethers tse nang le likhahla tse phahameng le li-viscosity tse tlase li bonts'a thixotropy esita le ka tlase ho mocheso oa gel. Thepa ena e na le molemo o moholo molemong oa kaho ea seretse sa moaho ho lokisa boemo ba eona le ho sag. Hoa lokela ho hlokomeloa mona hore ho phahama ha viscosity ea cellulose ether, ho boloka metsi ho molemo, empa ho phahama ha viscosity, ho phahamisa boima ba limolek'hule tsa cellulose ether, le ho fokotseha ho lekanang le ho qhibiliha ha eona, ho nang le bothata bo bobe. tšusumetso ho tsepamiso ea seretse le ho sebetsa.

Lebaka: Cellulose ether e na le phello e hlakileng ea ho kenya moea linthong tse ncha tse thehiloeng ho samente. Cellulose ether e na le sehlopha sa hydrophilic ka bobeli (sehlopha sa hydroxyl, sehlopha sa ether) le sehlopha sa hydrophobic (sehlopha sa methyl, selikalikoe sa tsoekere), se sebetsa ka holim'a metsi, se na le ts'ebetso ea holim'a metsi, 'me kahoo se na le phello ea moea. Phello ea moea ea cellulose ether e tla hlahisa phello ea "bolo", e ka ntlafatsang ts'ebetso ea lisebelisoa tse sa tsoa tsoakoa, tse kang ho eketsa polasetiki le boreleli ba seretse nakong ea ts'ebetso, e leng molemo oa ho betla seretse. ; e tla boela e eketse tlhahiso ea seretse. , ho fokotsa litšenyehelo tsa tlhahiso ea seretse; empa e tla eketsa porosity ea thepa e thata le ho fokotsa thepa ea eona ea mechine e kang matla le elastic modulus. Joaloka surfactant, cellulose ether e boetse e na le phello ea ho kolobisa kapa ea ho tlotsa ka likaroloana tsa samente, tseo hammoho le phello ea eona ea ho kenya moea e eketsang metsi a thepa e thehiloeng ho samente, empa phello ea eona e teteaneng e tla fokotsa metsi. Phello ea phallo ke motsoako oa polasetiki le liphello tse teteaneng. Ha litaba tsa cellulose ether li le tlase haholo, li bonahala haholo-holo e le polasetiki kapa phello ea ho fokotsa metsi; ha litaba li phahame, phello e matla ea cellulose ether e eketseha ka potlako, 'me phello ea eona ea ho kenya moea e atisa ho tlala, kahoo ts'ebetso e eketseha. Phello e matla kapa tlhokahalo e eketsehileng ea metsi.

Ho beha tieho: Cellulose ether e ka liehisa tšebetso ea hydration ea samente. Cellulose ethers e fa seretse ka thepa e fapaneng e molemo, hape e fokotsa ho lokolloa ha mocheso oa pele oa samente le ho liehisa ts'ebetso ea hydration kinetic ea samente. Sena ha se monate bakeng sa tšebeliso ea seretse libakeng tse batang. Ho lieha hona ho bakoa ke ho ata ha limolek'hule tsa cellulose ether lihlahisoa tsa hydration tse kang CSH le ca(OH)2. Ka lebaka la ho eketseha ha viscosity ea tharollo ea pore, cellulose ether e fokotsa ho tsamaea ha ion tharollo, kahoo e liehisa ts'ebetso ea hydration. Ha palo ea cellulose ether e phahame ka har'a lisebelisoa tsa gel ea liminerale, phello ea ho lieha ha hydration e bonahala haholoanyane. Li-cellulose ethers ha li fokolise feela ho beha, empa hape li sitisa mokhoa o thata oa tsamaiso ea seretse sa samente. Phello ea ho lieha ha cellulose ether ha e itšetlehe feela ka mahloriso a eona tsamaisong ea gel ea diminerale, empa hape le sebopeho sa lik'hemik'hale. Ha tekanyo ea methylation ea HEMC e phahame, e ntlafatsa phello ea ho lieha ea cellulose ether. Phello ea ho lieha e matla. Leha ho le joalo, viscosity ea cellulose ether ha e na phello e fokolang ho hydration kinetics ea samente. Ka keketseho ea cellulose ether content, nako ea ho beha seretse e eketseha haholo. Ho na le kamano e ntle e se nang moeli pakeng tsa nako ea pele ea ho beha seretse le litaba tsa cellulose ether, 'me nako ea ho qetela ea ho beha e na le kamano e ntle ea linear le litaba tsa cellulose ether. Re ka laola nako ea ts'ebetso ea seretse ka ho fetola litaba tsa cellulose ether. Sehlahisoang, e bapala karolo ea ho boloka metsi, ho tenya, ho liehisa matla a samente a hydration, le ho ntlafatsa ts'ebetso ea kaho. Bokhoni bo botle ba ho boloka metsi bo etsa hore samente ea gypsum molora oa calcium e arabele ka botlalo, e eketsa haholo viscosity e metsi, e ntlafatsa matla a tlamahano ea seretse, 'me ka nako e ts'oanang e ka ntlafatsa matla a thata le matla a ho kuta, e ntlafatsa haholo phello ea kaho le katleho ea mosebetsi. Nako e ka feto-fetohang. E ntlafatsa ho fafatsa kapa ho pompeha ha seretse, hammoho le matla a sebopeho. Ts'ebetsong ea 'nete ea kopo, hoa hlokahala ho tseba mofuta, viscosity le palo ea cellulose ho latela lihlahisoa tse fapaneng, mekhoa ea kaho le tikoloho.