Cellulose ethers, kunyanya hydroxypropylmethylcellulose (HPMC) uye methylhydroxyethylcellulose (MHEC), yakashandiswa zvakanyanya sesementitious zvinhu zvinowedzera mukuvaka zvikumbiro. Zvinozivikanwa nekuda kwekuchengetedza mvura, zvinhu izvi zvinogona kuwedzera kushanda, rheology uye kusimba kwechisungo chesimende zvinhu. Zvisinei, simba ravo pane simenti hydration haisi nguva dzose yakajeka.
Cement hydration inoreva kuita kwemakemikari pakati pemvura uye simende zvinhu kugadzira hydration zvigadzirwa senge calcium silicate hydrate (CSH) uye calcium hydroxide (Ca (OH) 2). Iyi nzira yakakosha pakuvandudzwa kwekonkriti's mechanical simba uye kusimba.
Kuwedzerwa kwe cellulose ethers kune cementitious zvinhu zvinogona kuva zvose zvakanaka uye zvakashata zvinokonzerwa ne hydration process. Kune rimwe divi, kuchengetwa kwemvura kuita kwe cellulose ether kunogona kukurudzira simenti kuti irambe ichiwana mvura yekuita, nekudaro ichiwedzera kukurumidza uye dhigirii remvura. Izvi zvinopfupisa nguva yekumisikidza, inomhanyisa kukura kwesimba uye inovandudza huwandu hwese hwekongiri.
Cellulose ether inogonawo kuita sechidziviriro colloid kudzivirira kuunganidzwa uye kugadzika kwemasimende zvimedu. Izvi zvinoguma mune imwe yunifomu uye yakagadzikana microstructure, iyo inowedzera kuwedzera michina uye yakasimba zvinhu zvekongiri.
Nekune rimwe divi, kushandisa zvakanyanya cellulose ethers kunogona kukanganisa simende hydration. Nekuti cellulose ether ine chikamu hydrophobic, inovharira kupinda kwemvura mugelling zvinhu, zvichikonzera kunonoka kana kusakwana hydration. Izvi zvinokonzera kuderedzwa kwesimba uye kusimba kwekrete.
Kana huwandu hwe cellulose ether hwakanyanya, huchatora nzvimbo mune simende slurry iyo inofanirwa kuzadzwa nesamende zvimedu. Nekuda kweizvozvo, iyo yakazara solids yemukati meiyo slurry inoderera, zvichikonzera kuderedzwa kwema mechanical properties. Yakawandisa cellulose ethers inogonawo kuita sechivharo, kudzivirira kupindirana pakati pesimende particles nemvura, zvichiwedzera kudzikisa pasi hydration process.
Izvo zvakakosha kuti uone huwandu hwakakwana hweselulosi ether yekushandisa kuvandudza zvimiro zveiyo gelled zvinhu uchidzivirira chero kukanganisa kunokanganisa hydration. Nhamba yacho inoenderana nezvinhu zvakawanda, zvakadai semhando ye cellulose ether, simenti yakagadzirwa, mvura-simende ratio uye kuporesa mamiriro.
Cellulose ethers, kunyanya HPMC neMHEC, inogona kuva nemigumisiro yakanaka pane simenti hydration, zvichienderana nekugadzirisa kwavo uye kuumbwa kwakananga kwezvinhu zvesimenti. Huwandu hwe cellulose ether hunoshandiswa hunofanirwa kunyatsotariswa kuti uwane zvivakwa zvinodiwa pasina kukanganisa maitiro ekongiri. Nekushandisa kwakaringana uye optimization, cellulose ethers inogona kubatsira mukuvandudzwa kwezvakanyanya kusimba, zvinogara kwenguva refu uye zvakagadzikana zvekuvaka.
Nguva yekutumira: Aug-23-2023