• OpenAccess
    • List of Articles 3D printing

      • Open Access Article

        1 - A Review of Mechanical Recycling of Polylactic Acid: Challenges and Recent Achievements
        Farzane Tabatabaee
        The growing use of polylactic acid (PLA) encourages technologists to conduct extensive research into valorization of PLA waste with best quality. In general, mechanical recycling of PLA is one of the most cost-effective recycling methods. However, recycled materials are More
        The growing use of polylactic acid (PLA) encourages technologists to conduct extensive research into valorization of PLA waste with best quality. In general, mechanical recycling of PLA is one of the most cost-effective recycling methods. However, recycled materials are commonly used for minor applications due to the inherent thermo-mechanical degradation of the polymer during recycling, which mainly results in chain scissions and intramolecular and intermolecular transesterification reactions. Therefore, it has a negative effect on the molar mass distribution and consequently on the mechanical, thermal and rheological properties of recycled PLA. In this article, a review of recent research on the effects of mechanical recycling on the properties of PLA including structural, morphological, mechanical, rheological and thermal changes was done. Furthermore, a review of three main ways of valorization of recycled PLA including thermal modification, chemical modifications in the presence of stabilizers, chain extenders, branching agents and finally mixing with nanoadditives or with other polymers was done in order to improve the properties of recycled PLA. Moreover, due to the widespread use of natural fibers to improve the performance of PLA, the recyclability of natural fiber-reinforced PLA biocomposites was investigated. Finally, two important applications of recycled PLA in the food packaging and the 3D printing industries were discussed. Manuscript profile
      • Open Access Article

        2 - A review of polymer 3D printing technology: materials, process and design strategies for medical applications
        amir hasnvand
        چكيده انگليسي Polymer 3D printing is an emerging technology that further research in this field will lead to continuous improvement of polymer 3D printing design performance, which is necessary to push the boundaries in engineering and medicine. Polymer 3D printing pr More
        چكيده انگليسي Polymer 3D printing is an emerging technology that further research in this field will lead to continuous improvement of polymer 3D printing design performance, which is necessary to push the boundaries in engineering and medicine. Polymer 3D printing provides the possibility of printing low-cost functional parts with various properties and capabilities. Here, by reviewing research on materials, processes and related strategies applied for medical applications, it is presented. Research in materials has led to the development of polymers with useful properties for mechanics and biocompatibility, by tuning the mechanical properties achieved by changing the parameters of the printing process. Polymer 3D printing technologies include extrusion, sheet lamination, Vat photo polymerization, additive layer, powder-based fusion, material projection, direct energy deposition. Thermal and laser inkjet techniques are more common. The two technologies of sheet exfoliation and direct energy deposition have limited medical applications. Which enables the direct deposition of design materials for useful and customized architectures. Design strategies, such as the hierarchical distribution of materials, make it possible to balance contrasting properties. The most investigated medical applications include tissue scaffolds, dental implants, medical education, delivery systems, and drug safety devices. And finally, the challenges and obstacles of polymer 3D printing were studied. Manuscript profile