Fabrication of a novel silicone-matrix composite reinforced with a 3D printed polymeric lattices and graphene oxide

Interpenetrating phase composites (IPCs) combining architected lattice structures with multifunctional matrices offer significant potential for lightweight and energy-absorbing applications. In this study, IPC specimens were fabricated by integrating 3D-printed lattice frameworks with a silicone matrix reinforced by graphene oxide (GO). The lattices were produced via fused filament fabrication and subsequently infiltrated with a silicone–GO mixture to form a continuous interpenetrating structure. The influence of GO content, lattice inclusion, and compression speed (2.5, 5, and 7.5 mm/min) on the microstructural characteristics and mechanical performance of the composites was systematically investigated. Scanning electron microscopy (SEM) revealed effective matrix infiltration into the lattice architecture and visually and apparently uniform dispersion of GO within the silicone phase, promoting strong interfacial bonding and improved load transfer. Microstructural observations indicated that GO sheets contributed to crack deflection and deformation stability, while the lattice framework provided a continuous load-bearing network. Mechanical characterization through uniaxial compression testing demonstrated a substantial enhancement in performance for lattice-reinforced specimens compared with matrix-only samples. Yield strength increased from approximately 0.65–2.10 MPa in NL specimens to about 18 MPa in lattice-containing IPCs, accompanied by a significant rise in toughness and energy absorption capacity. Stress–strain and force–displacement analyses showed that the IPCs exhibited distinct elastic, plateau, and densification regions characteristic of architected cellular materials. Increasing compression speed further improved post-yield resistance and energy absorption due to strain-rate sensitivity of the silicone–GO matrix. The results confirm that the mechanical behavior of IPCs is governed by a synergistic interaction between microstructure and architecture, where GO enhances interfacial reinforcement and the lattice structure controls stiffness and load-bearing efficiency. The developed IPC system demonstrates promising potential for applications requiring lightweight structures with high strength and energy absorption capability.