Effect of Superabsorbent Polymer on 3D Printing Characteristics as Rheology-Modified Agent

Author

Yu cun Gu
Kamal H. Khayat, Missouri University of Science and TechnologyFollow

Abstract

This study aims to investigate the effects of two superabsorbent polymer (SAP) types, S1 and S2 (with continual absorption and rapid desorption, respectively) as rheology-modified agent on 3D printing characteristics. Three base mixtures were selected with different thixotropic behaviors (i.e., mixtures with high re-flocculation (τfloc), high structuration rate (Athix), and both low τfloc and Athix, respectively). The initial mini-slump flow of 190±10 mm was secured by adjusting superplasticizer (SP) or water demand (increasing w/b by either 0.025 or 0.05). An extrudable region was determined within the range of τfloc (200-890 Pa) and Athix (15-60 Pa/min). The use of the S2 SAP significantly improved extruded performance for mixtures with τfloc higher than 1000 Pa. The use of the S1 SAP without increasing w/b (only with extra SP demand) significantly improved the resistance against plastic collapse for the mixtures with τfloc lower than 300 Pa. The reduction in 28-day compressive strength for printed specimens was correlated with τfloc. A high τfloc value led to inadequate interlayer bond and an increased propensity for surface defects of printed structure. The S2 SAP acted as a rheology-modified agent to reduce τfloc and improved the interlayer bond performance by 10%-20%.

Recommended Citation

Y. c. Gu and K. H. Khayat, "Effect of Superabsorbent Polymer on 3D Printing Characteristics as Rheology-Modified Agent," Construction and Building Materials, vol. 438, article no. 137140, Elsevier, Aug 2024.

The definitive version is available at https://doi.org/10.1016/j.conbuildmat.2024.137140

Department(s)

Civil, Architectural and Environmental Engineering

Keywords and Phrases

3D printing; buildability; extrudability; interlayer adhesion; superabsorbent polymers

International Standard Serial Number (ISSN)

0950-0618

Document Type

Article - Journal

Document Version

Citation

File Type

text

Language(s)

English

Rights

© 2024 Elsevier, All rights reserved.

Publication Date

09 Aug 2024