Projects / 3D-BONECRAFT

From molecular interfaces
to scaffold prototypes.

Development and evaluation of PHA–MXene biocomposites using molecular modelling, material preparation, characterisation, extrusion and 3D printing.

3D-printed scaffold prototype with a visible grid on top and layered side texture — Scaffold prototype produced by fused filament fabrication in 3D-BONECRAFT.

3D-BONECRAFT

How do polymer composition, MXene surface chemistry and processing shape a printable composite for bone scaffolds?

Coordinated by Bruno Faria, the project combines atomistic studies with the development and fabrication of materials.

Bone scaffolds need to combine biocompatibility with mechanical behaviour suited to the intended support and an architecture tailored to the tissue being repaired. For a biodegradable polymer scaffold, the challenge also includes producing the desired structure reliably by 3D printing.

3D-BONECRAFT explores PHA–MXene biocomposites as a route to this combination. PHA provides the biodegradable polymer matrix; MXene sheets offer a stiff, high-aspect-ratio phase with tunable surface chemistry and electrical conductivity. The project investigates how these features can be combined to improve the balance between processability, mechanical response and electrical functionality in filaments and scaffold prototypes.

Scientific questions

Three connected questions.

The interface

How do polymer architecture and surface chemistry affect molecular contact and interaction?

The material

How do formulation and preparation affect the material that can be characterised and processed?

The fabrication route

Which processing conditions allow filament production and the printing of structures?

Findings from three submitted manuscripts

From model choices
to material response.

Model choices Adsorption Tensile deformation

01 / Review · Submitted manuscript

The physical question
sets the model.

Polymers influence MXene composites beyond initial adsorption: they can bridge neighbouring sheets, reorganise water and ions, and alter the molecular environment governing material response.

Fragment calculations examine local chemical preferences. Explicit polymer chains and solvent in molecular dynamics address organisation and rearrangement; reactive models or ab initio dynamics are needed when changes in bonding are central.

Main conclusion

Meaningful comparison requires checking interactions between components, charge assignment, solvent representation and the observable being measured. The reviewed studies do not establish a universal ranking of polymers or surface terminations.

Bruno Faria. Computational Modeling of MXene–Polymer Composites for Biomaterials Research: From Model Choices to Material Behavior. Submitted manuscript.

02 / Adsorption · Submitted manuscript

How does chain architecture
shape surface contact?

The size and arrangement of the polymer backbone and side chains influence how a chain can settle on a MXene surface. Changes in chain architecture affect both surface contact and the interaction energy associated with adsorption.

Contact geometry and chemical interactions need to be considered together. More contact alone does not provide a complete description of the polymer–surface interaction.

Representative atomistic configuration of a polymer chain in contact with a MXene surface — Representative polymer–MXene configuration · Molecular dynamics

Model compositions: P(3HB), P(3HB-co-3HV), P(3HB-co-5HHx) and P(4H3PB), with O-, OH- and mixed O/OH-terminated Ti₃C₂Tₓ MXene. Temperature: 300 K.

Bruno Faria. Role of chain structure and surface termination in polyhydroxyalkanoate adsorption on Ti₃C₂Tₓ MXene. Submitted manuscript.

03 / Tensile deformation · Submitted manuscript

Visualising cavity evolution.

Three successive simulation views showing the evolution of a cavity around a MXene sheet; orange marks the interfacial region and violet the bulk region — Cavity evolution during deformation · Molecular simulation

Model compositions: PHA matrices with Ti₃C₂Tₓ MXene sheets, at 11.20–15.24 wt% MXene. Temperature: 300 K.

Bruno Faria. Mechanical Behavior and Structural Evolution of PHA–MXene Nanocomposites under Tensile Deformation. Submitted manuscript.

Material preparation & fabrication

Make the material.
Test the processing route.

Experimental work includes MXene preparation and treatment, material films, thermal and mechanical characterisation, extrusion and fused filament fabrication.

Original photographs below document the extrusion arrangement, filament production and printing of a scaffold prototype.