## 4 Conclusions  
By utilizing IR thermography to record the thermal history of a deposited layer, the progression of layer temperature over time can be directly extracted and implemented in the FSC device to simulate the associated processing conditions. Several print settings were varied, providing an opportunity to differentiate between the distinct print parameters to determine the most influential settings. Both liquefier temperature and print speed were found to barely impact the developed crystallinity. On the other hand, a substantial effect of the build plate temperature was observed, which can be attributed to the annealing imposed by the build plate. A significant amount of the total crystallinity seemed to have already been amassed during the initial cyclic heating and cooling cycles associated with the successive deposition of new layers in all conditions. However, the molecular weight of the printed polymer seemed to be of key importance for eventual part crystallinity, attaining a considerably higher degree of crystallinity compared to its high molecular weight counterpart printed under identical circumstances. However, the crystallinity of the both copolymers exhibited a notably less steep increase  
Figure 11: The development of crystallinity over the course of printing compared with the thermal history experienced by the monitored layers for: (**a**) Condition 1 (HMWPA); and (**b**) Condition 6 (LMWPA).  
during the third zone, while the build plate was cooling down. Fast Scanning Chip Calorimetry has thus proven itself as an effective tool to monitor the advancement of crystallinity of a printed part during FFF, which makes it possible to monitor and predict final part crystallinity and performance, once the thermal history of the printed part is established. This even opens up the possibility of employing temperature profiles derived from thermal models of the printing process, which would allow an assessment of final part crystallinity without the need of actually printing a physical object.  
Conceptualization, methodology, formal analysis, and investigation, D.V. and M.C.; writing--original draft preparation, D.V.; resources, B.G. and W.Z.; writing--review and editing, B.G., W.Z. and P.V.P.; supervision, W.Z. and P.V.P.; and project administration and funding acquisition, P.V.P.  
This research was funded by SIM Flanders (ICON project FLAMINCO; project number: HBC.2017.0325).  
The authors thankfully acknowledge [PERSON], [PERSON] and [PERSON] for insightful conversations regarding data analysis and interpretation.  
The authors declare no conflict of interest.  
The following abbreviations are used in this manuscript:  
\begin{tabular}{l l} AM & Additive Manufacturing \\
3D & Three-dimensional \\ CAD & Computer-aided-design \\ FFF & Fused Filament Fabrication \\ FDM & Fused Deposition Modeling \\ SLS & Selective Laser Sintering \\ SLA & Stereolithography \\ IR & Infrared \\ DSC & Differential Scanning Calorimetry \\ XRD & X-ray Diffraction \\ T\({}_{\text{g}}\) & Glass transition temperature [\({}^{\circ}\)C] \\ FSC & Fast Scanning Chip Calorimetry \\ M\({}_{\text{w}}\) & Weight average molecular weight [kg/mol] \\ T\({}_{\text{m}}\) & Melting temperature [\({}^{\circ}\)C] \\ HMWPA & High molecular weight PA \\ LMWPA & Low molecular weight PA \\ T\({}_{\text{liquefier}}\) & Liquefier temperature [\({}^{\circ}\)C] \\ T\({}_{\text{build plate}}\) & Build plate temperature [\({}^{\circ}\)C] \\ v\({}_{\text{print}}\) & Print speed [mm/s] \\ m\({}_{\text{FSC}}\) & FSC sample mass [ng] \\ m\({}_{\text{DSC}}\) & DSC sample mass [mg] \\ AH\({}_{\text{m,FSC}}\) & FSC melting enthalpy [m]] \\ AH\({}_{\text{m,DSC}}\) & DSC melting enthalpy [J] \\ \end{tabular}