english NOUR-DJIHANE MAZOUZI, KHALIDA BOUTEMAK, AHMAD HADDAD
Rezumat
Films based on hydroxypropylmethylcellulose (HPMC) find applications in for various applications due to their environmental nature, low cost, flexibility and transparency. However, the mechanical properties and moisture content need to be improved. The point of this study was to examine the impact of the magnesium oxide (MgO) addition on the physicochemical, mechanical and rheological properties of hydroxymethylcellulose films. HPMC/MgO composite films showed a four-fold increase in mechanical properties compared to unreinforced HPMC films. In addition, the addition of MgO nanoparticles reduced the moisture content to 2%. The latter was influenced by the difference in water solubility of various composite films, the incorporation of MgO into HPMC films improved the water barrier properties despite the increased water resistance value. Steam wettability was obtained for the HPMC/MgO composite film.
Cuvinte cheie
HPMC, MgO, nanoparticole, proprietăți reologice
HAO LI, WEI ZHOU, KSENIIA RUDENKO
Rezumat
High-performance fiber-reinforced cement composites (HPFRCCs) are attractive in applied in life-cycle structures. Hybrid properties of HPFRCCs with various fibers was experimentally investigated in this study. Three fibers contains the long and short smooth steel fibers and PE fibers, were blended into paste and mortar reinforced with 1.5% vol. fibers, respectively. Enhancements in mechanical properties including compressive strength and flexural strength, and workability were various for different types of fibers. The results show that for FRCCs with available amount of PE and steel fiber was achieved satisfactory workability. The better compressive strength was obtained at 28 day is 100.5MPa and 95.0MPa for the paste and the mortar, respectively. Incorporation of PE fiber in cement paste led to improvement in flexural strength. Microstructure has indicated effectively dense cementitious composites strong bond between the fibers and the cement paste for both of the mixes.
Cuvinte cheie
HPFRCC, rezistență la compresiune, rezistență la îndoire, lucrabilitate