Sika® ViscoCrete® SKY 8770

Sika® ViscoCrete® SKY 8770 is a superplasticizer of a new generation based on modified polycarboxylic ether polymers with super retention technology. The excellent dispersion effect makes Sika® ViscoCrete® SKY 8770 the ideal admixture for ready mix concrete industry, when superior performance is required, even under difficult conditions. Sika® ViscoCrete® SKY 8770 combines exceptional long slump life with normal setting times. Its application is especially beneficial when used in hot climate or with demanding mix designs. Sika® ViscoCrete® SKY 8770 does not contain added chloride and conforms to chloride ion limits required by concrete industry standards. Sika® ViscoCrete® SKY 8770 is universally applicable and provides improved rheological properties for a widerange of concrete mixes. Performance of Sika® ViscoCrete® SKY 8770 in concrete is superior to conventional superplasticizer due to its unique polycarboxylate ether design. Conventional superplasticizers, such as those based on sulphonated melamine and naphthalene formaldehyde condensates, at the same 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. Contrary to conventional superplasticizers the dispersion mechanism of Sika® ViscoCrete® SKY 8770 is not only based on electrostatic repulsion but in addition also on steric hindrances. Sika® ViscoCrete® SKY 8770 achieves outstanding water reduction and workability retention without retardation of setting time.