Functional design applied to additive manufacturing of bioplastic packaging

• Autor(a) principal: Campos, Gabriela de Jesus
• Data de Publicação: 2023
• Tipo de documento: Dissertação
• Idioma: eng
• Título da fonte: Repositório Científico de Acesso Aberto de Portugal (Repositórios Cientìficos)
• Texto Completo: http://hdl.handle.net/10773/39300
• topic: Adaptive design; Adaptive packaging; Biobased materials; Biodegradable packaging; Fused Filament Fabrication; FFF; Pharmaceutical packaging

Pharmaceutical packaging can be an obstacle for groups of people suffering from mobility-impairing diseases, as well for older people, which increases the need for adaptive packaging. On the other hand, multimaterial pharmaceutical packaging are non-recyclable, ending up often in landfills or disposed by incineration, raising environmental concerns. Functional design for additive manufacturing combined with biobased feedstocks has shown the possibility to enhance the usability of pharmaceutical packaging while minimizing its ecological footprint [1]. In the present Master dissertation, a functional design for easy-use refillable pharmaceutical packages processable by fused filament fabrication (FFF), an additive manufacturing technology, was developed. In addition, thermoplastic starch (TPS)-based filaments processable by FFF were developed. Under a circular economy concept, starch recovered from potato by-products was compounded with coffee byproducts, namely coffee silverskin (CS) and spent coffee grounds (SCG), as a strategy to improve the physicochemical/mechanical performance and processability by FFF of TPS-based materials. A commercially available polylactic acid (PLA)-based filament was used as a reference. The created 3D model for a pharmaceutical packaging took into consideration the user’s needs, in which the shape and texture were tuned to help the user’s grip ability. The developed design was able to be 3D printed by FFF using commercially available polylactic acid (PLA)- and thermoplastic polyurethane (TPU)-based filaments. Regarding the biobased formulations, CS and SCG conferred a brownish coloration to TPS-based materials. All TPS-, TPS/CS-, and TPS/SCG-based granulates were able to be extruded as filaments. Due to their brittle behavior, TPS based filaments did not show FFF ability, contrary to TPS/CS- and TPS/SCG-based ones. CS and SCG increased the rigidity and Shore A hardness of TPS-based materials, while still having high flexibility. 3D printed TPS/CS- and TPS/SCG-based specimens showed higher dimensions than the .STL project, reflecting their expansion after the 3D printing stage. All the 3D specimens had a rough and a smooth surface, and good adhesion between each layer. Moreover, due to the TPS chemical nature, the 3D specimens based on TPS/CS and TPS/SCG were quite hydrophilic, showing a great capacity of absorbing water molecules. Furthermore, due to CS and SCG bioactive molecules, they also possessed antioxidant activity. Overall, this master thesis highlighted that functional design can contribute to enhance the usability of pharmaceutical packaging and that potato and coffee processing by-products can be used to develop bioplastic feedstocks for filament extrusion and FFF, providing more knowledge on the suitability of using agrifood byproducts for the development of functional pharmaceutical packaging.