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Gypsum-Based Cements

The utilization of gypsum-based binary and ternary blended cements has been shown to provide the desired characteristics of early hardening strength with improved durability. This is illustrated in [Pg.482]


Nonhydraulic cements were among the most common of the ancient cements. The relatively high solubilities of portlandite (Ca[OH]2) and gypsum means that they deteriorate rapidly in moist or wet environments. Many decades ago, the Romans used lime-based cements and mortars (cement plus sand) by ramming the wet pastes... [Pg.219]

Chem. Descrip. Olefin sulfonate, sodium salt Uses Surfactant air entraining agent, plasticizer for building materials, plasters, textured decorative coatings, masonry mortars, gypsum- and cement-based prods. [Pg.406]

Poly (2-hydroxyethyl, Et) ether Ethyl hydroxyethyl cellulose. Etulos. EMEC [9004-58-4] Useful in solvent coating applications, inks, paints and as an additive to cement and gypsum based plasters and mortars Laxative. [Pg.238]

Uitilization of FGD gypsum in cement-based material is feasible. It is not only for environmental uses, but also in construction and civil engineering. The results contribute to a greater understanding of how to sustainably and beneficially manage various industrial wastes and byproducts and suggest that there are also several important environmental and economic benefits that can be realized. [Pg.171]

Gypsum-based plaster >- Cement- or gypsum-based vermiculite >- Mineral or glass fibre > Ceramic-based products... [Pg.185]

In gypsum-less cement, a conduction calorimetric study showed that a strong retardation of hydration occurred in the presence of a lignosulfonate-based superplasticizer containing sodium carbonate. l... [Pg.280]

In normal portland cement, hydration leads to the formation of ettringite. In many instances, the formation of ettringite leads to expansion. To prevent the formation of ettringite, a gypsum-based material with 75% hemihydrate, 20% portland cement, 5% silica fume, and a superplasticizer was fabricated. The pastes were cured in water for 1 to 10 minutes and subjected to DTA. In Fig. 10, thermograms show the stepwise dehydration endothermal peaks (shown upwards) at 150° and 200°C as is typical of gypsum. There was no indication of ettringite or monosulfate, which normally are identified by peaks at 125-130° and 190-195°C. [Pg.306]

Uses Surfactant, consistency agent, stabilizer, water retention aid in aq. prods., cement-based tile fix and joint mortars, gypsum-based crack fillers thickener Features Improves workability, adhesion in mortars Regulatory Europe EINECS... [Pg.154]

Improved workability and open time of dispersion-based systems such as tape joint compounds and aqueous coatings, as well as mineral-bound building systems such as cement-based mortars and gypsum-based plasters... [Pg.101]

Construction Soil stabilization water absorber water retention aids in cements, grouts, and tiles improvement of mechanical properties of cement and gypsum plasters and water based paints... [Pg.70]

The uncontrolled variation in the gypsum-hemihydrate or soluble anhydrite ratio (G-H or A) that occurs during production, storage and transportation of cement can cause compatibility problems with certain superplasticizers, particularly a reduction in workability. The extent of the reduction on workability properties is dependent on the G-H ratio (ranging from 80 20% to 20 80%), level of C A and alkalis present in the cement and the fineness of the cement. For the most reactive type of cement with a high content of both C A and alkalis, a reduced G-H or A ratio affects the yield stress, while piastre viscosity is not much affected. These effects are much less pronounced for a less reactive cement, but with the lowest G-H or A ratio, false set can occur [130-132], An increased fineness of cement increases the effect of the G-H or A ratio. The effect has been found to be most pronounced with melamine-based superplasticizers [130, 133],... [Pg.405]


See other pages where Gypsum-Based Cements is mentioned: [Pg.122]    [Pg.106]    [Pg.482]    [Pg.122]    [Pg.106]    [Pg.482]    [Pg.313]    [Pg.422]    [Pg.422]    [Pg.750]    [Pg.313]    [Pg.402]    [Pg.82]    [Pg.173]    [Pg.811]    [Pg.325]    [Pg.881]    [Pg.923]    [Pg.4703]    [Pg.33]    [Pg.342]    [Pg.308]    [Pg.161]    [Pg.212]    [Pg.199]    [Pg.352]    [Pg.687]    [Pg.253]    [Pg.1182]    [Pg.2525]    [Pg.348]    [Pg.403]    [Pg.471]    [Pg.233]    [Pg.371]    [Pg.572]    [Pg.351]    [Pg.71]    [Pg.55]    [Pg.273]   


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