Plasticized and reinforced poly(methyl methacrylate) obtained by a dissolution-dispersion process for single point incremental forming: Enhanced formability towards the fabrication of cranial implants

A plasticized and reinforced material made of poly(methyl methacrylate), PMMA, was developed via an effective dissolution-dispersion method to enhance its formability in Single Point Incremental Forming process (SPIF). Different contents of triacetine (plasticizer), and Cloisite 30B nanoclay (C-30B) used as reinforcement, were added to PMMA based on a factorial design of experiments with center points. A synergistic effect between triacetine and C-30B was evidenced during the SPIF processing of the PMMA composite material. The addition of triacetine produced the relaxation and mobility of polymer chains, while C-30B improved the mechanical properties without affecting the formability. The transfer of stresses during SPIF of cone-shaped parts was enhanced due to a mechanical interlocking effect between the nanoclay and the PMMA chains, in addition to the formation of intercalated nanostructures within the clay galleries. The potential application of these PMMA-based composite materials for manufacturing cranial implants is addressed in this work as well.