water reducer concrete admixturea FDN

water reducer

Product Description

PC super-plasticizer is an innovative new generation polycarboxylate ether based slump retaining aid with super retention technology. Additionally, it can help the ready-mixed, precast concrete industries, where more than normal slump retention and durability are required. PC super-plasticizer is a specifically tailored, stand alone product, the constituents of its active ingredient exhibiting unique adsorption characteristics to cement. PC super-plasticizer can be used in conjunction with modified lignosulphonate based admixtures only to aid in super slump retention of a concrete mix. The excellent dispersion effect makes it the ideal aid for the ready-mixed concrete, precast concrete industry, without affecting concrete setting times. The ability to work over a range of water binder ratios including low w/b ratios and still obtain

extended slump retention allows for the manufacture of high quality concrete.

Chemistry& Mechanism of Action

Conventional superplasticisers, such as those based on sulphonated melamine and naphthalene formaldehyde condensates, at the time of mixing, become absorbed onto the surface of the cement particles. This absorption takes place at a very early stage in the hydration process. The sulphonic groups of the polymer chains increase the negative charge on the surface of the cement particle and dispersion of the cement occurs by electrostatic repulsion. PC super-plasticizer is differentiated in that this unique polycarboxylate ether polymer with long lateral chains is tailored to generate a super slump retaining effect in combination with polycarboxylate ether and/or modified lingosulphonate based admixtures. This greatly improves cement dispersion and steric hindrance. At the start of the mixing process the same electrostatic dispersion occurs as described previously, but the presence of the lateral chains, linked to the polymer backbone, generates a steric hindrance which stabilizes the cement particles capacity to separate and disperse. This mechanism provides flowable concrete with greatly reduced water demand and aids in super slump retention.