BIO-BASED PH-RESPONSIVE SUPERABSORBENT POLYMERS FOR SELF- HEALING CRACKS IN CONCRETE

Author(s): Arn Mignon, Dries Devisscher, Jolien Vermeulen, Peter Dubruel, Sandra Van Vlierberghe, Nele De Belie
Paper category: Proceedings
Book title: proceedings of the International RILEM Conference on Materials, Systems and Structures in Civil Engineering Conference segment on Service Life of Cement-Based Materials and Structures
Editor(s): Miguel Azenha, Ivan Gabrijel, Dirk Schlicke, Terje Kanstad and Ole Mejlhede Jensen
ISBN:978-2-35158-170-4
e-ISBN: 978-2-35158-173-5
Publisher: RILEM Publications SARL
Publication year: 2016
Pages: 194-203
Total Pages: 10
Language : English

Abstract: Cracks endanger the durability of concrete. Introducing a superabsorbent polymer (SAP)
during concrete mixing can create a self-sealing and -healing construction. SAPs are able to
take up aqueous solutions up to several hundred times their own weight. Bio-based SAPs
starting from polysaccharides have gained increasing interest in recent years due to their
biocompatibility, non-toxicity and low price. The use of pH-responsive SAPs can also be
extremely useful as they should only swell more upon crack formation and less during mixing
of the SAPs in the concrete. The present work describes the development and the
characterization of SAPs based on methacrylated polysaccharides (alginate and chitosan)
combined with pH-responsive monomers dimethylaminoethyl methacrylate (DMAEMA) and
dimethylaminopropyl methacrylamide (DMAPMA). The materials exhibited a high moisture
uptake capacity up to 120% of their original weight with a negligible hysteresis. The pH-
responsive swelling behavior was studied in aqueous and cement filtrate solutions with a
varying pH. Chitosan combined with DMAEMA or DMAPMA showed the targeted pH-
responsive swelling. Chitosan combined with DMAPMA also showed a limited compression
strength reduction and a promising self-sealing and -healing behavior and could thus be
considered as a very interesting future solution to seal and heal cracks in concrete.

Online publication : 2016
Publication type : full_text
Public price (Euros) : 0.00