1 Selelekela
Chaena e 'nile ea khothalletsa seretse se kopantsoeng ka lilemo tse fetang 20. Haholo-holo lilemong tsa morao tjena, mafapha a mmuso a amehang a naha a 'nile a totobatsa bohlokoa ba nts'etsopele ea seretse se kopantsoeng ka botlalo 'me a fana ka maano a khothatsang. Hona joale, ho na le liprofinse le bomasepala ba fetang 10 naheng ba sebelisitseng seretse se kopantsoeng ka botlalo. Ho feta 60%, ho na le likhoebo tse fetang 800 tsa seretse se kopantsoeng ka botlalo tse fetang tekanyo e tloaelehileng, tse nang le bokhoni ba moralo oa selemo le selemo ba lithane tse limilione tse 274. Ka 2021, tlhahiso ea selemo le selemo ea seretse se kopantsoeng ka botlalo e ne e le lithane tse limilione tse 62.02.
Nakong ea ts'ebetso ea kaho, seretse hangata se lahleheloa ke metsi a mangata haholo 'me ha se na nako le metsi a lekaneng ho nosetsa, e leng se fellang ka matla a sa lekaneng le ho petsoha ha pente ea samente ka mor'a ho thatafala. Cellulose ether ke motsoako o tloaelehileng oa polymer ka seretseng se kopantsoeng ka omileng. E na le mesebetsi ea ho boloka metsi, ho teteana, ho lieha le ho kenya moea, 'me e ka ntlafatsa haholo ts'ebetso ea seretse.
E le ho etsa hore seretse se fihlelle litlhoko tsa lipalangoang le ho rarolla mathata a ho petsoha le matla a tlase a ho kopanya, ho bohlokoa haholo ho eketsa ether ea cellulose seretseng. Sengoloa sena se hlahisa ka bokhutšoanyane litšobotsi tsa ether ea cellulose le tšusumetso ea eona ts'ebetsong ea thepa e thehiloeng samente, ka tšepo ea ho thusa ho rarolla mathata a tekheniki a amanang le seretse se kopantsoeng se seng se loketse.
2 Selelekela ho ether ea cellulose
Cellulose Ether (Cellulose Ether) e entsoe ka cellulose ka karabelo ea etherification ea moemeli a le mong kapa ho feta oa etherification le ho sila ka omileng.
2.1 Tlhophiso ea li-ether tsa cellulose
Ho ya ka sebopeho sa dikhemikhale tsa dintho tse nkang sebaka sa ether, di-ether tsa cellulose di ka arolwa ka di-ether tsa anionic, cationic le nonionic. Di-ether tsa cellulose tsa Ionic di kenyeletsa haholo-holo carboxymethyl cellulose ether (CMC); di-ether tsa cellulose tse seng ionic di kenyeletsa haholo-holo methyl cellulose ether (MC), hydroxypropyl methyl cellulose ether (HPMC) le hydroxyethyl fiber Ether (HC) le tse ding. Di-ether tse seng ionic di arotswe ka di-ether tse qhibilihang ka metsing le di-ether tse qhibilihang ka oli. Di-ether tse qhibilihang ka metsing tse seng ionic di sebediswa haholo-holo dihlahisweng tsa seretse. Ha ho na le di-ion tsa calcium, di-ether tsa cellulose tsa ionic ha di tsitse, kahoo ha di sebediswe hangata dihlahisweng tsa seretse se ommeng se sebedisang samente, lime e slaked, jj. e le thepa ya samente. Di-ether tsa cellulose tse qhibilihang ka metsi tse seng ionic di sebediswa haholo indastering ya thepa ya kaho ka lebaka la botsitso ba tsona ba ho emisoa le phello ya ho boloka metsi.
Ho ya ka di-agent tse fapaneng tsa etherification tse kgethilweng tshebetsong ya etherification, dihlahiswa tsa ether tsa cellulose di kenyeletsa methyl cellulose, hydroxyethyl cellulose, hydroxyethyl methyl cellulose, cyanoethyl cellulose, carboxymethyl cellulose, Ethyl cellulose, benzyl cellulose, carboxymethyl hydroxyethyl cellulose, hydroxypropyl methyl cellulose, benzyl cyanoethyl cellulose le phenyl cellulose.
Li-ether tsa cellulose tse sebelisoang ka har'a seretse hangata li kenyelletsa methyl cellulose ether (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose ether (HEMC) le hydroxyethyl cellulose ether (HEMC). Har'a tsona, HPMC le HEMC ke tsona tse sebelisoang haholo.
2.2 Thepa ea lik'hemik'hale ea ether ea cellulose
Ether e 'ngoe le e 'ngoe ea cellulose e na le sebopeho sa motheo sa sebopeho sa cellulose-anhydroglucose. Nakong ea ho hlahisa ether ea cellulose, fiber ea cellulose e futhumatsoa pele ka tharollo ea alkaline ebe e phekoloa ka moemeli oa etherifying. Sehlahisoa sa karabelo ea fibrous sea hloekisoa 'me sea siloa ho etsa phofo e tšoanang e nang le botenya bo itseng.
Tlhahisong ea MC, ke methyl chloride feela e sebelisoang e le moemeli oa etherifying; ntle le methyl chloride, propylene oxide e boetse e sebelisoa ho fumana lintho tse nkeloang sebaka ke hydroxypropyl tlhahisong ea HPMC. Li-ether tse fapaneng tsa cellulose li na le sekhahla se fapaneng sa phetolo ea methyl le hydroxypropyl, tse amang ho lumellana ha lintho tse phelang le mocheso oa gel oa tharollo ea ether ea cellulose.
2.3 Litšobotsi tsa ho qhibiliha ha ether ea cellulose
Litšobotsi tsa ho qhibiliha ha ether ea cellulose li na le tšusumetso e kholo ho sebetseng ha seretse sa samente. Ether ea cellulose e ka sebelisoa ho ntlafatsa ho kopana le ho boloka metsi ha seretse sa samente, empa sena se itšetlehile ka hore ether ea cellulose e qhibilihe ka botlalo ka metsing. Mabaka a ka sehloohong a amang ho qhibiliha ha ether ea cellulose ke nako ea ho qhibiliha, lebelo la ho hlohlelletsa le ho ba bonolo ha phofo.
2.4 Karolo ea ho teba ka seretseng sa samente
Jwalo ka sehlomathiso sa bohlokwa sa slurry ya samente, Destroy e na le phello ya yona dikarolong tse latelang.
(1) Ntlafatsa ho sebetsa ha seretse le ho eketsa ho teteana ha seretse.
Ho kenyelletsa lelakabe la mollo ho ka thibela seretse ho arohana le ho fumana 'mele oa polasetiki o tšoanang le o tšoanang. Mohlala, maphephe a kenyelletsang HEMC, HPMC, jj., a loketse seretse se nang le lera le lesesaane le ho plaster. , Sekhahla sa ho kuta, mocheso, mahloriso a ho putlama le mahloriso a letsoai le qhibilihisitsoeng.
(2) E na le phello ea ho kenya moea.
Ka lebaka la litšila, ho kenngoa ha lihlopha ka har'a likaroloana ho fokotsa matla a bokaholimo ba likaroloana, 'me ho bonolo ho kenya likaroloana tse tsitsitseng, tse tšoanang le tse tšesaane ka har'a seretse se kopantsoeng le bokaholimo bo hlohlelletsang nakong ea ts'ebetso. "Bokhoni ba bolo" bo ntlafatsa ts'ebetso ea kaho ea seretse, bo fokotsa mongobo oa seretse le ho fokotsa ho tsamaisoa ha mocheso oa seretse. Liteko li bontšitse hore ha bongata ba ho kopanya ba HEMC le HPMC e le 0.5%, bongata ba khase ba seretse ke bo boholo ka ho fetisisa, bo ka bang 55%; ha bongata ba ho kopanya bo feta 0.5%, botebo ba seretse butle-butle bo fetoha mokhoa oa bongata ba khase ha bongata bo ntse bo eketseha.
(3) E boloke e sa fetoha.
Boka bo ka qhibiliha, ba tlotsa le ho hlohlelletsa seretse, mme ba nolofatsa lera le lesesaane la seretse le phofo ea ho plaster. Ha ho hlokahale hore e kolobisoe esale pele. Kamora kaho, thepa e etsang samente e ka boela ea ba le nako e telele ea metsi a tsoelang pele lebopong ho ntlafatsa ho khomarelana pakeng tsa seretse le substrate.
Litlamorao tsa phetoho ea ether ea cellulose holim'a thepa e foreshe e thehiloeng samenteng li kenyelletsa haholo-holo ho teteana, ho boloka metsi, ho kenella moeeng le ho lieha. Ka tšebeliso e pharaletseng ea ether ea cellulose linthong tse thehiloeng samenteng, tšebelisano lipakeng tsa ether ea cellulose le slurry ea samente butle-butle e fetoha sebaka se hohelang lipatlisiso.
Nako ea poso: Tshitwe-16-2021