Hemp reinforced polylactic acid (pla) composite produced by fused filament fabrication (fff)


Doğru A., Sözen A., Seydibeyoğlu M. Ö., Neşer G.

Hacettepe Journal of Biology and Chemistry, cilt.50, sa.3, ss.239-246, 2022 (Hakemli Dergi)

Özet

Reinforcement of polymer matrix with natural fibre can provide an increase in mechanical properties of the related composite. Since thermoplastics, especially biocomposite materials are recyclable, they contribute to a sustainable ecosystem. In this study, 10% by weight hemp-reinforced polylactic acid (PLA) matrix compounds were produced. Tensile test specimens were performed in two different infill patterns, parallel and +/- 45° cross, using the Fused Filament Fabrication (FFF) method from the developed biocomposite filaments. Ultimate tensile stress increases by approximately 20%. It has been observed that the geometry of the infill pattern greatly affects the tensile strength. In addition, through optical and scanning electron microscopy (SEM) the produced composite filaments were examined. Surface interactions and homogeneous fibre distribution between PLA and hemp were investigated. As a result, hemp was used as a reinforcement material in the study. Homogeneous distribution is very important in the preparation of the compounds and a twin-screw extruder was used to achieve this. However, it has been observed that the interface between fibre and matrix is insufficient. This situation negatively affects structural performance. On the other hand, the addition of hemp decreases the thermal resistance and melting temperature and increases the glass transition temperature compared to pure PLA.