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A new type of photocrosslinkable Polycaprolactone (PCL) based ink that is suitable for 3D inkjet printing has been developed. Photocrosslinkable PCL dimethylacrylate was synthesized and mixed with Poly(ethylene glycol) di-acrylate (PEGDA) to prepare an ink with a suitable viscosity for inkjet printing. The ink performance under different printing environments, initiator concentrations and post-process was studied. This showed that a Nitrogen atmosphere during printing was beneficial for curing and material property optimisation, as well as improving the quality of structures produced. A simple structure, building in the z direction, demonstrated the potential for this material for the production of 3D printed objects. Cells testwas carried out to investigate the biocompatibility of the developed ink.

A method using experimental nanoindentation and inverse finite-element analysis (FEA) has been developed that enables the spatial variation of material constitutive properties to be accurately determined. The method was used to measure property variation in a three-dimensional printed (3DP) polymeric material. The accuracy of the method is dependent on the applicability of the constitutive model used in the inverse FEA, hence four potential material models: viscoelastic, viscoelastic-viscoplastic, nonlinear viscoelastic and nonlinear viscoelastic-viscoplastic were evaluated, with the latter enabling the best fit to experimental data. Significant changes in material properties were seen in the depth direction of the 3DP sample, which could be linked to the degree of cross-linking within the material, a feature inherent in a UV-cured layer-by-layer construction method. It is proposed that the method is a powerful tool in the analysis of manufacturing processes with potential spatial property variation that will also enable the accurate prediction of final manufactured part performance.