1 Nhanganyaya
China yanga ichisimudzira dhaka rakagadzirwa-yakasanganiswa kwemakore anopfuura makumi maviri. Kunyanya mumakore achangopfuura, madhipatimendi ehurumende yenyika akakoshesa kugadzirwa kwedhaka rakasanganiswa uye akapa mitemo inokurudzira. Parizvino, kune matunhu nemakanzuru anodarika gumi munyika ashandisa dhaka rakagadzirwa. Kupfuura 60%, kune anopfuura mazana masere akagadzirira-akavhenganiswa mabhizinesi edhaka pamusoro peyakajairwa chiyero, ane gore negore dhizaini inokwana 274 miriyoni matani. Muna 2021, kugadzirwa kwepagore kweyakajairika yakasanganiswa dhaka yaive 62.02 miriyoni matani.
Munguva yekuvaka, dhaka rinowanzorasikirwa nemvura yakawandisa uye harina nguva yakakwana uye mvura yekunyorovesa, zvichikonzera kusakwana kwesimba uye kuputika kwesamende paste mushure mekuoma. Cellulose ether yakajairika polymer musanganiswa mudhaka rakaoma-musanganiswa. Iine mabasa ekuchengetedza mvura, kukora, kunonoka uye kupindira kwemhepo, uye inogona kuvandudza zvakanyanya kushanda kwedhaka.
Kuti iite kuti dhaka rizadzise zvinodiwa zvekufambisa uye kugadzirisa matambudziko ekuputika uye kuderera kwesimba rekubatanidza, zvakakosha zvikuru kuwedzera cellulose ether kune dhaka. Ichi chinyorwa chinozivisa muchidimbu maitiro e-cellulose ether uye simba rayo pakushanda kwesimende-based materials, achitarisira kubatsira kugadzirisa zvinetso zvehutano zvine chokuita nedhaka rakagadzirwa-yakasanganiswa.
2 Nhanganyaya kune cellulose ether
Cellulose Ether (Cellulose Ether) inogadzirwa kubva kune cellulose kuburikidza ne etherification reaction yeimwe kana kupfuura etherification agents uye yakaoma kugaya.
2.1 Kurongwa kwe cellulose ethers
Zvinoenderana nechimiro chemakemikari eether substituents, cellulose ethers inogona kukamurwa kuita anionic, cationic uye nonionic ethers. Ionic cellulose ethers inonyanya kusanganisira carboxymethyl cellulose ether (CMC); non-ionic cellulose ethers inonyanya kusanganisira methyl cellulose ether (MC), hydroxypropyl methyl cellulose ether (HPMC) uye hydroxyethyl fiber Ether (HC) nezvimwe zvakadaro. Non-ionic ethers yakakamurwa kuva ether-soluble ethers uye ether-soluble ethers. Non-ionic mvura-soluble ethers inonyanya kushandiswa muzvigadzirwa zvematope. Muhupo hwe calcium ions, ionic cellulose ethers haina kugadzikana, saka haiwanzoshandiswa mune yakaoma-musanganiswa wedhaka zvigadzirwa zvinoshandisa simenti, slaked lime, nezvimwewo semasimende zvinhu. Non-ionic water-soluble cellulose ethers anoshandiswa zvakanyanya muindasitiri yezvivakwa zvekuvaka nekuda kwekumira kwavo kugadzikana uye mhedzisiro yemvura.
Zvinoenderana neakasiyana etherification maajenti akasarudzwa muiyo etherification process, zvigadzirwa zve cellulose ether zvinosanganisira methyl cellulose, hydroxyethyl cellulose, hydroxyethyl methyl cellulose, cyanoethyl cellulose, carboxymethyl cellulose, Ethyl cellulose, benzyl cellulose, carboxymethyl hydroxyethyl cellulose, methylzylzylcyulose cellulose, methylzylzylcyulose cellulose, hydroxyethyl cellulose. phenyl cellulose.
Cellulose ethers inoshandiswa mudhaka inowanzobatanidza methyl cellulose ether (MC), hydroxypropyl methyl cellulose (HPMC), hydroxyethyl methyl cellulose ether (HEMC) uye hydroxyethyl cellulose ether (HEMC) Pakati pavo, HPMC uye HEMC ndiyo inonyanya kushandiswa.
2.2 Hunhu hwemakemikari hwe cellulose ether
Imwe neimwe cellulose ether ine yakakosha chimiro che cellulose-anhydroglucose chimiro. Mukugadzira cellulose ether, iyo cellulose fiber inotanga kupiswa mumushonga wealkaline wozobatwa ne etherifying agent. Iyo fibrous reaction product inonatswa uye inogayiwa kuita hupfu hwakafanana nehumwe hunyoro.
Mukugadzirwa kweMC, chete methyl chloride inoshandiswa se etherifying agent; kunze kwemethyl chloride, propylene oxide inoshandiswawo kuwana hydroxypropyl substituents mukugadzirwa kweHPMC. Akasiyana-siyana cellulose ethers ane akasiyana methyl uye hydroxypropyl substitution rates, izvo zvinokanganisa kugarisana kwe organic uye tembiricha yegel yemafuta emushonga we cellulose ether.
2.3 Mamiriro ekuparara kwe cellulose ether
Mamiriro ekuparara kwe cellulose ether ane simba guru pakushanda kwesamende dhaka. Cellulose ether inogona kushandiswa kuvandudza kubatana uye kuchengetwa kwemvura kwesamende dhaka, asi izvi zvinoenderana ne cellulose ether iri zvachose uye yakanyungudika zvizere mumvura. Zvinhu zvikuru zvinokanganisa kupera kwe cellulose ether inguva yekuparara, kukurumidza kukurumidza uye hupfu hwakatsetseka.
2.4 Basa rekunyura mudhaka resimende
Sekuwedzera kwakakosha kwesamende slurry, Paradzai ine mhedzisiro yayo mune zvinotevera zvinhu.
(1) Kuvandudza kushanda kwedhaka uye kuwedzera viscosity yedhaka.
Kubatanidza flame jet kunogona kudzivirira dhaka kubva pakuparadzanisa uye kuwana yunifomu uye yunifomu yepurasitiki muviri. Semuyenzaniso, matumba anosanganisira HEMC, HPMC, zvichingodaro, ari nyore kune yakaonda-layer dhaka uye plastering. , Shear rate, tembiricha, kudonha kunyura uye yakanyungudika munyu.
(2) Iine mhepo-intraining effect.
Pamusana pekusachena, kuiswa kwemapoka muzvikamu kunoderedza simba repamusoro rezvikamu, uye zviri nyore kuunza zvakagadzikana, yunifomu uye zvimedu zvakanaka mumatope akasanganiswa nepamusoro-soro mukugadzirisa. "Ball performance" inovandudza kushanda kwekuvaka kwedhaka, inoderedza unyoro hwevhu uye inoderedza kupisa kwemhepo yevhu. Miedzo yakaratidza kuti kana huwandu hwekubatanidza hweHEMC neHPMC huri 0.5%, iyo gasi yedhaka ndiyo yakakura, inenge 55%; kana huwandu hwekusanganiswa hwakakura kupfuura 0.5%, zviri mudhaka zvishoma nezvishoma zvinokura kuita gasi yemukati maitiro sezvo huwandu hunowedzera.
(3) Chengetedza isina kuchinja.
Wakisi inokwanisa kunyungudika, kuzora nekukuchidzira mudhaka, uye kufambisa kutsvedzerera kwedhaka rakatetepa redhaka nehupfu hwekupurapura. Haidi kunyoroveswa pachine nguva. Mushure mekuvaka, iyo cementitious zvinhu zvinogona zvakare kuve nenguva yakareba yekuenderera hydration pamhenderekedzo yegungwa kuvandudza kunamatira pakati pedhaka uye substrate.
Kugadziriswa kweselulosi ether pazvinhu zvitsva-zvakavakirwa simende zvinonyanya zvinosanganisira kukora, kuchengetedza mvura, kupinza mhepo uye kunonoka. Nekushandiswa kwakapararira kwema cellulose ethers mune sement-based materials, kudyidzana pakati pema cellulose ethers necement slurry zvishoma nezvishoma kuri kuita hotspot yekutsvagisa.
Nguva yekutumira: Zvita-16-2021