Cement-based materials modified with superabsorbent polymers: A review

Cement-based materials modified with SAP have been attracting much attention worldwide due to their excellent crack resistance and durability as well as their wide availability and low cost. This paper reviews the processing and microstructures (hydration process and pore structure) of SAP-modified cement-based composites and discusses the effects of SAP on the rheological properties, mechanical properties, shrinkage, self-healing and durability of cement-based materials. In general, the addition of SAP introduces additional water that can ensure the workability of the mixture and has little impact on their mechanical properties compared with cement-based materials without SAP. Moreover, the addition of SAP can significantly reduce the autogenous shrinkage of cement-based materials, thereby improving their crack resistance and durability (impermeability, carbonation resistance and frost resistance). When SAP is added into cement-based materials, the effects of SAP on the properties of cement-based materials depend on the SAP particle size, content and addition method. Finally, the applications of cement-based materials modified with SAP are introduced in detail, and the challenges and prospects of SAP-modified cement-based composites are discussed.