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Information × Registration Number 0223U003507, 0121U113295 , R & D reports Title Influence of water-retaining and redispersing additives on the properties of the cement matrix popup.stage_title Head Tokarchuk Volodymyr V., к.т.н. Registration Date 16-05-2023 Organization National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute" popup.description2 The influence of methylhydroxyethyl cellulose additives on the technical and physico-mechanical properties of cement systems was studied. Cellulose ether of low (11,000 – 16,000 mPa∙s), medium (17,000–23,000 mPa∙s) and high (20,000 – 30,000 mPa∙s) viscosity was introduced into cement in amounts of 0.25, 0.5 and 0.75 mass %. The addition of cellulose ether to cement leads to an increase in the normal thickness of the dough and an extension of the hardening time of the solutions. The normal density of the cement dough increases with the introduction of cellulose ethers of low (LV) and medium viscosity (SE) by 5.4–16.8%, and with the introduction of high viscosity ether (BB) by 21.3–41.4 %. This confirms the high water-holding capacity of methylhydroxyethyl cellulose, which increases with increasing viscosity of additives. Depending on the concentration and viscosity of the additives, the hardening time of the cement paste increases by 2-4 times compared to the material without additives. There is also a significant decrease in the strength of the cement matrix in the early stages of hardening (1–7 days), depending on the concentration of additives by 2.2–4.2 times. Low-viscosity cellulose ether reduces the strength of samples the least, and high-viscosity the most. A decrease in strength is also noted at the age of 28 days, but it is not so noticeable. Compared to cement without additives, the strength is: for ether of low viscosity at concentrations: 0.25 wt. % – 14.3%, 0.50 wt. % – 23.9%, 0.75 wt. % – 40.5%, for medium viscosity ether, respectively, 23.8; 26.2 and 33.3%, and for high viscosity ether 28.6; 45.2 and 61.0%. The corrosion resistance of the cement matrix with methylhydroxyethyl cellulose additives increases at a concentration of up to 0.25 wt. %, and then gradually decreases. The given results make it possible to recommend the use of cellulose ethers of low and medium viscosity in the production of dry construction mixtures, which will ensure the necess Product Description popup.authors Kovalenko Yurii Oleksiyovych Tokarchuk Volodymyr Volodymyrovych popup.nrat_date 2023-05-16 Close