Search results
Results from the WOW.Com Content Network
Superplasticizers (SPs), also known as high range water reducers, are additives used for making high-strength concrete or to place self-compacting concrete. Plasticizers are chemical compounds enabling the production of concrete with approximately 15% less water content. Superplasticizers allow reduction in water content by 30% or more.
Of commercial importance are the alkylnaphthalene sulfonates, which are used as superplasticizers in concrete. They are produced on a large scale by condensation of naphthalenesulfonate or alkylnaphthalenesulfonates with formaldehyde. [1] [2] Examples include: amaranth dye; amido black; armstrong's acid; congo red; Evans blue; suramin; trypan blue
These inexpensive products were derived from wood and paper industry, but are now advantageously replaced by other synthetic sulfonate and polycarboxylate, also known as superplasticizers. Water reducers offer several advantages in their use, listed below: reduces the water content by 5-10%; decreases the concrete porosity
Gel permeation chromatography (GPC) has become the most widely used technique for analyzing polymer samples in order to determine their molecular weights and weight distributions. Examples of GPC chromatograms of polystyrene samples with their molecular weights and dispersities are shown on the left.
In the concrete technology, plasticizers and superplasticizers are also called high range water reducers. When added to concrete mixtures, they confer a number of properties including improved workability and strength. The strength of concrete is inversely proportional to the amount of water added, i.e., the water-cement (w/c) ratio.
However, most HPFRCCs include at least the following ingredients: fine aggregates, a superplasticizer, polymeric or metallic fibers, cement, and water. Thus the principal difference between HPFRCC and typical concrete composition lies in HPFRCCs' lack of coarse aggregates. Typically, a fine aggregate such as silica sand is used in HPFRCCs.
Polycarboxylate ethers (PCE) are used as superplasticizers in concrete production. [3] Safety. Polycarboxylates are poorly biodegradable but have a low ecotoxicity.
Genuine Parts Company (GPC) is an American automotive and industrial parts distributor based in Atlanta, Georgia. [1] Established by brothers Carlyle and Malcolm Fraser in 1928, the company has approximately 60,000 employees. [ 2 ]