Li-admixtures li phetha karolo ea bohlokoa ho ntlafatsa ts'ebetso ea ho haha seretse se omileng, empa ho eketsoa ha seretse se omileng ho etsa hore theko ea thepa ea lihlahisoa tsa seretse se omeletseng e phahame haholo ho feta ea seretse sa setso, se ikarabellang ho feta 40% ea theko ea thepa ka seretse se kopantseng se ommeng. Hona joale, karolo e kholo ea motsoako o fanoa ke bahlahisi ba tsoang linaheng tse ling, 'me tekanyo ea litšupiso ea sehlahisoa e boetse e fanoa ke mofani oa thepa. Ka lebaka leo, litšenyehelo tsa lihlahisoa tsa seretse tse omeletseng li lula li le holimo, 'me ho thata ho tsebahatsa masela a tloaelehileng a masonry le li-plastering ka bongata le libaka tse pharaletseng; lihlahisoa tsa 'maraka oa maemo a holimo li laoloa ke lik'hamphani tsa linaha tse ling,' me baetsi ba seretse se omeletseng ba na le phaello e tlaase le mamello e fokolang ea theko; Ho na le khaello ea liphuputso tse hlophisitsoeng le tse lebisitsoeng mabapi le tšebeliso ea meriana, 'me mekhoa ea linaheng tse ling e lateloa ka bofofu.
Ho ipapisitsoe le mabaka a boletsoeng ka holimo, pampiri ena e sekaseka le ho bapisa lisebelisoa tse ling tsa mantlha tsa li-admixtures tse sebelisoang hangata, 'me motheong ona, e ithuta ts'ebetso ea lihlahisoa tsa seretse tse omeletseng tse sebelisang li-admixtures.
1. Moemeli oa ho boloka metsi
Setsi sa ho boloka metsi ke motsoako oa bohlokoa oa ho ntlafatsa ts'ebetso ea ho boloka metsi ea seretse se tsoakiloeng, hape ke e 'ngoe ea metsoako ea bohlokoa ho fumana litšenyehelo tsa lisebelisoa tsa seretse se omeletseng.
1.1 Cellulose ether
Cellulose ether ke lentsoe le akaretsang bakeng sa letoto la lihlahisoa tse hlahisoang ke karabelo ea alkali cellulose le etherifying agent tlasa maemo a itseng. Alkali cellulose e nkeloa sebaka ke lisebelisoa tse fapaneng tsa etherifying ho fumana li-ether tse fapaneng tsa cellulose. Ho latela thepa ea ionization ea li-substituent, cellulose ethers e ka aroloa ka mekhahlelo e 'meli: ionic (joalo ka carboxymethyl cellulose) le non-ionic (joalo ka methyl cellulose). Ho latela mofuta oa substituent, cellulose ether e ka aroloa ka monoether (joalo ka methyl cellulose) le ether e tsoakiloeng (joalo ka hydroxypropyl methyl cellulose). Ho ea ka solubility e fapaneng, e ka aroloa ka metsi a qhibilihang (joalo ka hydroxyethyl cellulose) le organic solvent-soluble (joalo ka ethyl cellulose), joalo-joalo. e arotsoe ka mofuta oa hang-hang le mofuta o tšoaroang ka holim'a nako e liehang ho qhibiliha.
Mokhoa oa ts'ebetso ea cellulose ether ka seretse ke ka tsela e latelang:
(1) Ka mor'a hore cellulose ether ka seretse e qhibilihe ka metsing, kabo e sebetsang le e ts'oanang ea thepa ea samente tsamaisong e tiisitsoe ka lebaka la mosebetsi oa holim'a metsi, 'me cellulose ether, e le colloid e sireletsang, "e phuthela" e tiileng. likaroloana le Lera la filimi e tlotsang e thehoa holim'a eona ka ntle, e leng se etsang hore tsamaiso ea seretse e be e tsitsitseng, hape e ntlafatsa ho phalla ha seretse nakong ea ho kopanya le boreledi ba kaho.
(2) Ka lebaka la sebopeho sa eona sa limolek'hule, tharollo ea cellulose ether e etsa hore metsi a seretse a se ke a lahleheloa ke bonolo, 'me butle-butle a e lokolla ka nako e telele, e leng se etsang hore seretse se boloke metsi hantle le ho sebetsa hantle.
1.1.1 Foromo ea molek'hule ea methyl cellulose (MC) [C6H7O2(OH)3-h(OCH3)n]x
Ka mor'a hore k'hothone e hloekisitsoeng e phekoloe ka alkali, cellulose ether e hlahisoa ka letoto la liketso ka methane chloride e le etherification agent. Ka kakaretso, tekanyo ea ho fetola ke 1.6 ~ 2.0, 'me solubility e boetse e fapane le likhato tse fapaneng tsa ho fetola. Ke ea non-ionic cellulose ether.
(1) Methylcellulose e qhibiliha ka metsing a batang, 'me ho tla ba thata ho qhibiliha ka metsing a chesang. Tharollo ea eona ea metsi e tsitsitse haholo maemong a pH = 3 ~ 12. E na le tumellano e ntle le starch, guar gum, joalo-joalo le li-surfactants tse ngata. Ha mocheso o fihla mocheso oa gelation, gelation e etsahala.
(2) Ho boloka metsi a methyl cellulose ho ipapisitse le palo ea eona ea tlatsetso, viscosity, botle ba likaroloana le sekhahla sa ho qhibiliha. Ka kakaretso, haeba palo ea tlatsetso e le kholo, botle bo nyane, 'me viscosity e kholo, sekhahla sa ho boloka metsi se phahame. Har'a bona, palo ea ho eketsoa e na le tšusumetso e kholo ka ho fetisisa ho tekanyo ea ho boloka metsi, 'me boemo ba viscosity ha bo lekane ka ho toba le tekanyo ea ho boloka metsi. Sekhahla sa ho qhibiliha haholo-holo se itšetlehile ka tekanyo ea phetoho ea bokaholimo ba likaroloana tsa cellulose le botle ba likaroloana. Har'a li-ether tsa cellulose tse ka holimo, methyl cellulose le hydroxypropyl methyl cellulose li na le litekanyetso tse phahameng tsa ho boloka metsi.
(3) Liphetoho tsa mocheso li tla ama ka botebo tekanyo ea ho boloka metsi ea methyl cellulose. Ka kakaretso, ha thempereichara e phahame, ho mpefala ha metsi ho boloka metsi. Haeba mocheso oa seretse o feta 40 ° C, ho boloka metsi a methyl cellulose ho tla fokotseha haholo, ho ama ka ho teba ho hahoa ha seretse.
(4) Methyl cellulose e na le phello e kholo mohahong le ho khomarela seretse. "Ho khomarela" mona ho bolela matla a sekhomaretsi a utloahalang pakeng tsa sesebelisoa sa mosebetsi le karoloana ea lebota, ke hore, ho hanyetsa ha seretse. Sekhomaretsi se phahame, khanyetso ea ho kuta ea seretse e kholo, 'me matla a hlokoang ke basebetsi ha a ntse a sebelisoa le ona a maholo,' me ts'ebetso ea kaho ea seretse e futsanehile. Methyl cellulose adhesion e boemong bo itekanetseng lihlahisoa tsa cellulose ether.
1.1.2 Foromo ea molek'hule ea hydroxypropyl methylcellulose (HPMC) ke [C6H7O2(OH)3-mn(OCH3)m,OCH2CH(OH)CH3]n]x
Hydroxypropyl methylcellulose ke mofuta oa cellulose oo tlhahiso le tšebeliso ea tsona li ntseng li eketseha ka potlako lilemong tsa morao tjena. Ke selulose e seng ionic e tsoakiloeng e entsoeng ka k'hothone e hloekisitsoeng ka mor'a alkalization, e sebelisa propylene oxide le methyl chloride e le etherification agent, ka letoto la liketso. Tekanyo ea ho nka sebaka ka kakaretso ke 1.2 ~ 2.0. Thepa ea eona e fapane ka lebaka la likarohano tse fapaneng tsa litaba tsa methoxyl le litaba tsa hydroxypropyl.
(1) Hydroxypropyl methylcellulose e qhibiliha habonolo metsing a batang, 'me e tla kopana le mathata a ho qhibiliha metsing a chesang. Empa mocheso oa eona oa gelation metsing a chesang o phahame haholo ho feta oa methyl cellulose. Ho qhibiliha ha metsi a batang ho boetse ho ntlafala haholo ha ho bapisoa le methyl cellulose.
(2) Viscosity ea hydroxypropyl methylcellulose e amana le boima ba eona ba molek'hule, 'me ha boima ba molek'hule bo le boholo, ho ba le viscosity e phahameng. Mocheso o boetse o ama viscosity ea eona, ha mocheso o ntse o eketseha, viscosity e fokotseha. Leha ho le joalo, viscosity ea eona e phahameng e na le phello e tlase ea mocheso ho feta methyl cellulose. Tharollo ea eona e tsitsitse ha e bolokiloe mocheso oa kamore.
(3) Ho bolokoa ha metsi a hydroxypropyl methylcellulose ho itšetlehile ka palo ea eona ea tlatsetso, viscosity, joalo-joalo, 'me sekhahla sa eona sa ho boloka metsi tlas'a chelete e tšoanang ea tlatsetso e phahame ho feta ea methyl cellulose.
(4) Hydroxypropyl methylcellulose e tsitsitse ho acid le alkali, 'me tharollo ea eona ea metsi e tsitsitse haholo ka har'a pH = 2 ~ 12. Caustic soda le metsi a lime ha li na phello e fokolang ts'ebetsong ea eona, empa alkali e ka potlakisa ho qhibiliha ha eona le ho eketsa viscosity ea eona. Hydroxypropyl methylcellulose e tsitsitse ho matsoai a tloaelehileng, empa ha motsoako oa motsoako oa letsoai o phahame, viscosity ea hydroxypropyl methylcellulose tharollo e atisa ho eketseha.
(5) Hydroxypropyl methylcellulose e ka kopanngoa le metsoako ea polymer e qhibilihang ka metsing ho etsa tharollo e tšoanang le e phahameng ea viscosity. Joalo ka joala ba polyvinyl, starch ether, boka ba meroho, joalo-joalo.
(6) Hydroxypropyl methylcellulose e na le khanyetso e ntle ea enzyme ho feta methylcellulose, 'me tharollo ea eona ha e na monyetla oa ho senyeha ka li-enzyme ho feta methylcellulose.
(7) Ho khomarela ha hydroxypropyl methylcellulose mohahong oa seretse ho phahame ho feta methylcellulose.
1.1.3 Hydroxyethylcellulose (HEC)
E entsoe ka k'hothone e hloekisitsoeng e tšoaroang ka alkali, 'me e itšoara ka ethylene oxide e le etherification agent ka pel'a acetone. Tekanyo ea ho nka sebaka ka kakaretso ke 1.5 ~ 2.0. E na le hydrophilicity e matla 'me e bonolo ho monya mongobo.
(1) Hydroxyethyl cellulose e qhibiliha ka metsing a batang, empa ho thata ho qhibiliha ka metsing a chesang. Tharollo ea eona e tsitsitse mocheso o phahameng ntle le gelling. E ka sebelisoa nako e telele tlas'a mocheso o phahameng ka har'a seretse, empa ho boloka metsi a eona ho tlaase ho feta methyl cellulose.
(2) Hydroxyethyl cellulose e tsitsitse ho acid e akaretsang le alkali. Alkali e ka potlakisa ho qhibiliha ha eona 'me ea eketsa viscosity hanyenyane. Ho qhalana ha eona metsing ho mpe ho feta ea methyl cellulose le hydroxypropyl methyl cellulose. .
(3) Hydroxyethyl cellulose e na le ts'ebetso e ntle ea anti-sag bakeng sa seretse, empa e na le nako e telele ea ho chechisa samente.
(4) Ts'ebetso ea hydroxyethyl cellulose e hlahisoang ke likhoebo tse ling tsa malapeng ho hlakile hore e tlase ho feta ea methyl cellulose ka lebaka la metsi a mangata le molora o mongata.
1.1.4 Carboxymethylcellulose (CMC) [C6H7O2(OH)2och2COONA]n
Ionic cellulose ether e entsoe ka likhoele tsa tlhaho (cotton, joalo-joalo) kamora kalafo ea alkali, ho sebelisoa sodium monochloroacetate joalo ka etherification agent, le ho etsa letoto la liphekolo tsa karabelo. Tekanyo ea ho kenya sebaka ka kakaretso ke 0.4 ~ 1.4, 'me ts'ebetso ea eona e angoa haholo ke tekanyo ea ho kenya sebaka.
(1) Carboxymethyl cellulose e na le hygroscopic, 'me e tla ba le metsi a mangata ha a bolokiloe tlas'a maemo a tloaelehileng.
(2) Carboxymethyl cellulose aqueous solution e ke ke ea hlahisa gel, 'me viscosity e tla fokotseha ka ho eketseha ha mocheso. Ha mocheso o feta 50 ° C, viscosity ha e fetohe.
(3) Ho tsitsa ha eona ho angoa haholo ke pH. Ka kakaretso, e ka sebelisoa seretseng se thehiloeng ho gypsum, empa eseng ka seretseng sa samente. Ha e le alkaline e ngata, e lahleheloa ke viscosity.
(4) Palo ea eona ea metsi e tlase haholo ho feta ea methyl cellulose. E na le phello e sitisang seretse se thehiloeng ho gypsum mme e fokotsa matla a eona. Leha ho le joalo, theko ea carboxymethyl cellulose e tlase haholo ho feta ea methyl cellulose.
Nako ea poso: Mar-30-2023