Structural characterization of carbonaceous fillers in UV curable conductive composites

There is an increasing need and demand on next generation materials able to sense and detect surrounding physical and chemical solicitations. In this sense, multifunctional hybrid materials, obtained by the combination of functional fillers and appropriate polymers are highlighted. Here, composites based on photopolymerization emerge as the most suitable ones due to advantages such as fast and room temperature curing or improved accuracy of the printed object. However, relevant experimental drawbacks in terms of the limitation of the amount of filler added, as well as in the deterioration of the mechanical properties have been identified. The physico-chemical characterization carried out with different electrically conductive composites based on carbonaceous fillers reveal a different behaviour depending on the particle shape employed and probably ascribed to the different nanostructural organization of the fillers within the polymer matrix. Thus, learning about the filler dispersion and polymer-filler interactions is of crucial importance for a better understanding of the main macroscopic properties of UV cured nanocomposites, thereafter also allowing to improve the preparation methods. Moreover, as carbonaceous fillers and a polymer matrix are employed, whose contrast is not resolvable with SAXS, our only option to determine their structure is using neutrons as scatterers (i.e. with SANS), as the SLD of the filler and the matrix are well distinguishable.