Title: Novel Polymer Blends as Concrete Superplasticizers

Author(s): X. Zhang, M. Page, Y. Denomme, and C. Jolicoeur

Publication: Symposium Paper

Volume: 235

Issue:

Appears on pages(s): 217-240

Keywords: admixtures; cement; concrete; mortar; paste; polyacrylate; polynaphthalene sulfonate; slump retention; superplasticizer

DOI: 10.14359/15912

Date: 3/22/2006

Abstract:
Component blending is a common practice in concrete chemical admixtures, for example, in water-reducing admixtures comprising lignosulfonate salts and other synthetic or naturally-occurring chemicals. Recent developments in polymer chemistry have generated a variety of new superplasticizers, mostly polyacrylate esters (PAE), which exhibit properties remarkably different from those of conventional superplasticizers such as PNS, or PMS. In principle, it would be appealing to combine the latter with PAE polymers in order to take advantage of their complementary features; unfortunately these polymer families are generally found to be mutually incompatible in cementitious systems. New polymer blends (PNS-X43) comprising an optimized conventional superplasticizer and new polycarboxylate co-polymers have now been developed that improves the slump retention of PNS at low W/C, typically, 0.35-0.40. The results obtained with this blend in various pastes, mortars and concrete are compared to those achieved with a PAE superplasticizer representative of the most effective product currently available.