Engineers at Princeton University have developed a new cement composite, inspired by the material found within certain shells, that is 17 times more crack-resistant than standard cement and 19 times more able to stretch and deform without breaking. 

The research team was led by Reza Moini, an assistant professor of civil and environmental engineering. In a recently published article in the journal Advanced Functional Materials, the team reported that creating alternating layers of tabulated cement paste and thin polymer can significantly increase the material’s durability. 

Often looking towards biology for inspiration in their work on building materials, the researchers were drawn to a natural material called nacre, also known as mother of pearl. The material is produced by some molluscs as an inner shell layer, and it is also the material that pearls are made of. According to the researchers, nacre consists of a hard mineral called aragonite, which are glued together by a soft biopolymer. The aragonite contributes to nacre’s strength, while the biopolymer adds flexibility and crack resistance. 

Inspired by nacre, the team developed composites made of conventional construction materials, such as Portland cement paste, combined with a highly stretchable polymer. They created multi-layered small beams by alternating layers of these materials. The beams were then tested under flexure to evaluate crack resistance. They were compared to a reference solid cast cement paste. The reference beams broke suddenly upon reaching their failure point, whereas the beams with alternating layers exhibited increased malleability and resistance to cracking. 

The researchers have asserted that more work and research is required to develop the techniques for use in the field. Additionally, they are now working to determine whether this process can be applied to other ceramic materials beyond cement paste, such as concrete.