Title: An Amphoteric Copolymer as a Concrete Admixture

Author(s): K.C. Hsu, J.W. Chen, F.T. Jiang, and D.S. Hwung

Publication: Symposium Paper

Volume: 239

Issue:

Appears on pages(s): 309-320

Keywords: amphoteric copolymer; cement; concrete; fluidity; workability

DOI: 10.14359/18387

Date: 10/1/2006

Abstract:
Superplasticizer is one key component to greatly increase the workability of concrete. In this study, an amphoteric copolymer (PDA) was prepared and evaluated as concrete admixture. PDA was prepared froma-N, N-dimethyl-N-(3- bcarboxylate) acrylamino) propylammonium ethanate and acrylamide through free radical polymerization. The test results on cement pastes indicate that this polymer could uniformly disperse cement particles and enhance the fluidity of the system. Compared to a commercial sulfonated naphthalene formaldehyde condensates (NSF) superplasticizer, PDA requires less dosage to achieve good fluidity and provides better fluidity retention. Limited test data also show that PDA has better performance than NSF in terms of slump flow and flow retention of the resulting concrete.