Mubvunzo mupfupi nezve cellulose ethers

Cellulose ethers iboka rakasiyana-siyana remakemikari anobva ku cellulose, iyo iri organic polymer yakawanda kwazvo pasi pano. Makemikoro aya anoshandiswa zvakanyanya mumaindasitiri akasiyana-siyana nekuda kwehunhu hwawo hwakasiyana uye mashandisirwo awo akasiyana-siyana.

Maumbirwo uye Hunhu hweMaEther eCellulose
Cellulose, polysaccharide ine mayuniti eglucose anodzokororwa akabatana ne β(1→4) glycosidic bonds, inoshanda sechinhu chikuru chekuvaka mumadziro emasero emiti. Cellulose ethers inogadzirwa nekuchinja makemikari mapoka ehydroxyl (-OH) ari mu cellulose molecule. Mhando dzakajairika dze cellulose ethers dzinosanganisira methyl cellulose (MC), hydroxypropyl cellulose (HPC), hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), uye ethyl hydroxyethyl cellulose (EHEC).

Kutsiviwa kwemapoka ehydroxyl mu cellulose nemapoka akasiyana-siyana anoshanda kunoshandura hunhu hwe cellulose ethers dzinobuda. Semuenzaniso, kuunzwa kwemapoka emethyl kunowedzera kunyungudika kwemvura uye hunhu hwekugadzira firimu, zvichiita kuti MC ive yakakodzera kushandiswa mumishonga, zvigadzirwa zvekudya, uye zvinhu zvekuvaka. Saizvozvowo, kuiswa kwemapoka ehydroxyethyl kana hydroxypropyl kunovandudza kuchengetedza mvura, kugona kukora, uye kunamira, zvichiita kuti HEC neHPC zvive zvinhu zvinokosha muzvigadzirwa zvekuchengetedza munhu, pendi, uye zvinonamatira. Carboxymethyl cellulose, inogadzirwa nekutsiva mapoka ehydroxyl nemapoka ecarboxymethyl, inoratidza hunhu hwakanaka hwekuchengetedza mvura, kugadzikana, uye kukora, zvichiita kuti ishandiswe zvakanyanya muindasitiri yechikafu, mishonga, uye sechinowedzera mvura muchikamu chemafuta negesi.

Dhigirii rekutsiva (DS), iro rinoratidza huwandu hweavhareji yemapoka ehydroxyl anotsiviwa pachikamu chimwe nechimwe cheglucose mu cellulose, rinokanganisa zvakanyanya hunhu hwe cellulose ethers. DS yakakwira inowanzo kukonzera kuwedzera kwekunyungudika, viscosity, uye kugadzikana, asi kutsiva kwakanyanya kunogona kukanganisa kuora kwehupenyu uye humwe hunhu hunodiwa hwe cellulose ethers.

Kugadzirwa kweCellulose Ethers
Kugadzirwa kwe cellulose ethers kunosanganisira maitiro emakemikari anounza mapoka anotsiva kumusana we cellulose. Imwe yenzira dzakajairika dzekugadzira cellulose ethers ndeye etherification ye cellulose uchishandisa reagents dzakakodzera mumamiriro ezvinhu akadzorwa.

Semuenzaniso, kugadzirwa kwemethyl cellulose kunowanzo sanganisira kuita kwecellulose nealkali metal hydroxides kugadzira alkali cellulose, zvichiteverwa nekurapwa nemethyl chloride kana dimethyl sulfate kuti iunze mapoka emethyl pane cellulose chain. Saizvozvowo, hydroxypropyl cellulose nehydroxyethyl cellulose zvinogadzirwa nekuita cellulose nepropylene oxide kana ethylene oxide, zvichiteerana, pamberi pealkali catalysts.

Carboxymethyl cellulose inogadzirwa kuburikidza nekuita kwe cellulose ne sodium hydroxide uye chloroacetic acid kana sodium salt yayo. Maitiro e carboxymethylation anoitika kuburikidza ne nucleophilic substitution, apo hydroxyl group ye cellulose inobatana ne chloroacetic acid kugadzira carboxymethyl ether linkage.

Kugadzirwa kwe cellulose ethers kunoda kungwarira kudzora mamiriro ekuita, akadai sekupisa, pH, uye nguva yekuita, kuti uwane mwero unodiwa wekutsiva uye hunhu hwechigadzirwa. Pamusoro pezvo, matanho ekuchenesa anowanzo shandiswa kubvisa zvimwe zvinhu netsvina, zvichiita kuti ive nechokwadi chekuti cellulose ethers dzakanaka uye dzakafanana.

Mashandisirwo eCellulose Ethers
Cellulose ethers dzinoshandiswa zvakanyanya mumaindasitiri akasiyana-siyana nekuda kwehunhu hwadzo hwakasiyana uye mashandiro adzo. Mamwe emashandisirwo akakosha anosanganisira:

Indasitiri yezvekudya:Cellulose ethersZvakadai se carboxymethyl cellulose zvinowanzo shandiswa sezvinhu zvinosimbisa, zvinosimbisa, uye zvinosanganisa chikafu muzvigadzirwa zvekudya zvakaita semasosi, madhirowa, uye ice cream. Zvinovandudza magadzirirwo, kunaka, uye kugadzikana kwesherufu uku zvichiwedzera kunzwa kwemuromo uye kuburitswa kwekuravira.

Mishonga: Methyl cellulose nehydroxypropyl cellulose zvinoshandiswa zvakanyanya mumishonga sezvinobatanidza, zvinoparadza, uye zvinodzora kuburitsa mishonga mumapiritsi, makapisiri, uye mishonga yemudumbu. Aya ma cellulose ethers anovandudza kuendeswa kwemishonga, kuwanikwa kwemishonga mumuviri, uye kutevedzera zvinodiwa nemurwere.

Zvinhu Zvokuvaka: Methyl cellulose nehydroxyethyl cellulose zvinoshandiswa muindasitiri yekuvaka sezvinhu zvinowedzerwa mumortars, plasters, uye tile adhesives kuti zviwedzere kushanda, kuchengetedza mvura, uye hunhu hwekunamira. Zvinovandudza kubatana, kuderedza kutsemuka, uye kuwedzera mashandiro ezvigadzirwa zvekuvaka.

Zvigadzirwa Zvekuchengetedza Munhu: Hydroxyethyl cellulose uye hydroxypropyl cellulose zvinhu zvinowanikwa muzvigadzirwa zvekuchengetedza munhu zvakaita semashampoo, mafuta ekuchenesa, uye makirimu.

o hunhu hwadzo hwekukora, kugadzikana, uye kugadzira firimu. Dzinovandudza kugadzikana kwechigadzirwa, magadzirirwo, uye kunzwa kweganda uku dzichiwedzera kugadzikana kwekugadzirwa kwacho.

Pendi Nemapendi: Cellulose ethers dzinoshanda se rheology modifiers, thickeners, uye stabilizers mumapendi, mapendi, uye manamati, zvichivandudza hunhu hwekushandisa, maitiro ekuyerera, uye kugadzirwa kwefirimu. Dzinowedzera kudzora viscosity, kusadzikama, uye kugadzikana kwemavara mumaformulation anobva mumvura.

Indasitiri yeOiri neGasi: Carboxymethyl cellulose inoshandiswa semuchina wekugadzirisa viscosity uye muchina wekutonga kurasikirwa kwemvura mukuchera mvura yekuongorora nekugadzira mafuta negasi. Inovandudza rheology yemvura, kuchenesa maburi, uye kugadzikana kwenzvimbo dzemvura uku ichidzivirira kukuvara kwekugadzira.

Indasitiri yeMachira: Cellulose ethers inoshandiswa mukudhinda, kudhaya, uye kupedzisa machira kuti iwedzere kutsanangurwa kwekudhinda, kubereka mavara, uye kupfava kwemachira. Anobatsira kupararira kwepigment, kunamira kumafiber, uye kukurumidza kugezwa mumachira.

Cellulose ethersinomiririra boka rakasiyana-siyana remakemikari anobva ku cellulose, achipa hunhu hwakasiyana-siyana uye mashandiro ekushandiswa kwakasiyana-siyana mumaindasitiri. Kuburikidza nekuchinja kwemakemikari kwakadzorwa kwemusana we cellulose, cellulose ethers inoratidza hunhu hunodiwa senge kunyungudika kwemvura, kudzora viscosity, uye kugadzikana, zvichiita kuti ive zvinhu zvinobatsira zvikuru mumaindasitiri kubva pakudya nemishonga kusvika pakuvaka nemachira. Sezvo kudiwa kwezvinhu zvinogara kwenguva refu uye zvine hushamwari kune zvakatipoteredza kuri kuramba kuchikura, cellulose ethers dzakagadzirira kutamba basa rakakosha mukusangana nezvinodiwa zvemaindasitiri emazuva ano uku dzichideredza kukanganisa kwezvakatipoteredza.