Material extrusion 3D printing (ME3DP) based on fused deposition modeling (FDM) technology is currently the most commonly used additive manufacturing method. However, ME3DP suffers from a limitation of compatible materials and typically relies upon amorphous thermoplastics, such as acrylonitrile butadiene styrene (ABS). The work presented here demonstrates the development and implementation of binary and ternary polymeric blends for ME3DP. Multiple blends of acrylonitrile butadiene styrene (ABS), styrene ethylene butadiene styrene (SEBS), and ultrahigh molecular weight polyethylene (UHMWPE) were created through a twin screw compounding process to produce novel polymer blends compatible with ME3DP platforms. Mechanical testing and fractography were used to characterize the different physical properties of these new blends. Though the new blends possessed different physical properties, compatibility with ME3DP platforms was maintained. Also, a decrease in surface roughness of a standard test piece was observed for some blends as compared with ABS.

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The chemical synthesis of gold nanoparticles (NP) by using gold (III) chloride trihydrate (HAuCl∙3H2O) and sodium citrate as a reducing agent in aqueous conditions at 100 °C is presented here. Gold nanoparticles areformed by a galvanic replacement mechanism as described by Lee and Messiel. Morphology of gold-NP was analyzed by way of high-resolution transmission electron microscopy; results indicate a six-fold icosahedral symmetry with an average size distribution of 22 nm. In order to understand the mechanical behaviors, like hardness and elastic moduli, gold-NP were subjected to nanoindentation measurements—obtaining a hardness value of 1.72 GPa and elastic modulus of 100 GPa in a 3–5 nm of displacement at the nanoparticle’s surface.

Polylactide/hydroxyapatite (PLA/HA) composites are promising tissue engineering materials because of the PLA biodegradability and HA as a natural bone component. PLA/HA composites without HA modification lead to mechanical failure due to the interfacial immiscibility. In this study, an effective chemical surface methodology is used to modify HA to obtain PLA/HA composites with superior mechanical properties. The HA particles are modified with fatty acids (adipic, sebacic, lauric, and linoleic) and incorporated into a PLA matrix by polymer solution casting, using chloroform as the solvent. After the HA modification, the films exhibited an improvement in tensile strength, elongation at break, and elastic modulus. Yet, the best results observed are by sebacic and adipic acid modification. These increments are attributed to a higher affinity of the organo‐modified HA particles within the PLA matrix. Therefore, the development of materials for osteo‐regeneration engineering based on these systems is quite promising.