BIOPOLYMER-MODIFIED CEMENTITIOUS MATERIALS FOR 3D PRINTED COMPOSITE: RHEOLOGY, PRINTABILITY, AND SUSTAINABILITY – A REVIEW

Abstract

The growing demand for sustainable construction technologies has accelerated research into 3D printed concrete (3DPC) materials as a resource-efficient and digitally controlled construction technique. However, achieving the required balance between flowability, buildability, and structural stability by using synthetic admixtures remains a key challenge in terms of cost-efficient printable composites. Biopolymers have emerged as promising eco-friendly and sustainable modifiers capable of enhancing rheological control while supporting sustainability objectives. This review examines the mechanisms, opportunities, limitations, and sustainability implications of incorporating biopolymers into 3D printable cementitious systems. Biopolymers such as guar gum, xanthan gum, and cellulose derivatives influence rheological behavior through polymer-water and polymer-cement particle interactions, enhancing yield stress, viscosity, and thixotropic recovery. These effects improve extrusion stability, layer stacking capacity, shape retention, and interlayer bonding strength. Biopolymers offer advantages including renewable sourcing, biodegradability, and reduced reliance on synthetic admixtures. Despite challenges regarding dosage optimization, durability, performance standardization, and scalable implementation, this review establishes a unified framework linking molecular interactions to printability performance and sustainability metrics, providing strategic guidance for the development of next-generation, low-carbon 3D printed cement composites.