Title:
Properties of an Acrylic graft Copolymer-Based New Superplasticizer for Ultra High-Strength Concrete
Author(s):
M. KinoshitaI
Publication:
Symposium Paper
Volume:
148
Issue:
Appears on pages(s):
281-300
Keywords:
acrylics; adsorption; cement pastes; compressive strength; high-strength concretes; mortars (material); water-cement ratio; plastics, polymers, and resins; silica fume; superplasticizers; tension; viscosity; workability; Materials Research
DOI:
10.14359/4108
Date:
9/1/1994
Abstract:
To place ultra-high-strength concrete with a compressive strength exceeding 100 MPa on site, technology is required to impart high fluidity to the concrete, with a water-to-cementitious material ratio in an extremely low range, 0.25 or less. For this purpose, the authors synthesized a new superplasticizer comprising water-soluble acrylic graft copolymer, which has excellent cement-dispersing capability. Paper reports investigation of the surface chemical properties of the new superplasticizer and those properties of the cement paste and mortar containing it. It was confirmed that the new superplasticizer imparts a higher fluidity to cement paste and mortar, with a lower range of water-to-cementitious material ratio than conventional superplasticizers. It was also found that the surface tension of the solution of the new superplasticizer is similar to that of conventional polycarboxylate superplasticizers, whereas the adsorption by cement and zeta potential of the new superplasticizer is between those of the ¯-naphthalene superplasticizers and the polycarboxylate superplasticizers. The high fluidity of the cement paste and mortar containing the new superplasticizer with a low-range water-to-cementitious material ratio may be particularly attributable to the preceding properties with respect to surface tension as well as molecular weight and chemical structure of the graft copolymer.