30-11-2012, 03:06 PM
Acro-POM-113
Typical Applications
Some typical applications of hydrocolloids in construction industry are –
1. Cement based Plasters- Cement based plasters are applied on exterior as well as
interior walls of buildings. Use of hydrocolloid in cement mortar prolongs the workability of cement-sand-water paste. Hydrocolloid in the cement paste reduces loss of water by capillary absorption into the bricks and stones, constituting the wall. Their presence helps in smooth spreading of the plaster on wall surface, improve consistency of plaster; controls air entrainment and water retention. This results in improved setting of cement, without much need of external curing by frequent wetting of the vertical surfaces.
2. Masonry mortar- All the advantages referred above are also obtained by using
Hydrocolloids, in masonry mortars. Spreading of mortar, between successive layers of bricks / stone blocks becomes easy due to lubricating action of hydrocolloid. Intimate adherence of mortar on to the masonry surface gives in strong binding and the mechanical strength of the joint is improved.
3. Self-leveling flooring formulation- Smooth consistency is provided to the flooring compound, and it helps in uniform leveling of floor. Hydrocolloid in a flooring composition also acts to prolong setting time, without frequent curing or wetting of the surface, minimizing shrinkage and crack formation.
4. Pre-fabricated and Extruded RCC structures- These are mass produced and used extensively in construction work. In the manufacture of pre-fabricated products, their mechanical process-ability is improved as well as wet strength and binding.
5. Gypsum based decorative plasters- Gypsum plasters are not meant to be exposed to rain or other wetting conditions. Use of hydrocolloid in such plasters, prolongs their working time, due to slow release of water required for their setting and makes their spreading easy. Use of a synthetic water insoluble vinyl or acrylic emulsion, along with a hydrocolloid can make gypsum plaster water-resistant.
6. Repair work such as crack filling, grouting and jointing composition- High lubricity produced by hydrocolloid in cement paste, helps in penetration and filling of cracks and use in jointing compositions. The shrinkage is minimized and the bonding strength is maximized. For grouting, the cement slurries remain pourable and give high ultimate strength.
7. Ceramic tile adhesive- Ceramic tiles used in washroom and kitchen are glazed on outer side. In their applications, moisture retention by the cement-based paste has to be maximized, because curing cannot be done. The use of hydrocolloid blended dement mortar, minimizes the capillary absorption by the unglazed side of the tile as well as the wall surface to which the tiles are fixed. Setting of the adhesive paste, takes place, without curing (keeping wet) as water can’t be sprinkled at the joint and setting / hardening takes place only by the water present in the adhesive paste.