Page 293 - IJB-9-4

International Journal of Bioprinting 3D printing of continuous fiber reinforced PLA/PGA composites

Figure 14. Influence of print layer thickness and print spacing on porosity, fiber content, and tensile strength according to (A) different layer thicknesses
and (B) different print spacings.

Table 3. Tensile strengths of fused deposition modeling (FDM) In this work, single-factor experiments were used to
polymer materials and composites investigate the influence of four process parameters on the
mechanical properties of PLA/PGA composites. However,
Materials Reinforcement method Tensile
strength (MPa) the effect of the combination of multiple process parameters
PLA (this work) - 37.60 on the mechanical properties of the printed part cannot
be well revealed by the single-factor experiment. On the
PEEK [42] - 95.21 basis of this study, multi-factor and multi-level process
CFR-PEEK [42] Short fiber 101.41 parameter experiments by orthogonal experiments are
PCL/PGA [39] Continuous fiber 79.70 warranted in future studies, and the relationship between
PLA/PGA (this work) Continuous fiber 209.32 the process parameters and the mechanical properties of
Cortical bone [43] - 60–160 the printed part should be investigated to determine the
optimal process parameters.
Abbreviations: CFR-PEEK, carbon-fiber-reinforced polyether ether
ketone; PCL, poly (ε-caprolactone); PEEK, polyether ether ketone; PGA,
polyglycolic acid; PLA, polylactic acid. 5. Conclusion
deposited line printed at the original set filament feeding In summary, the 3D-printed continuous PGA fiber-
speed of 0.1 mm/s does not connect well, and it is necessary reinforced PLA composite specimens showed good
to improve the connection between deposited lines by mechanical properties. The main conclusions of this work
accelerating the filament feeding speed. Based on the above are as follows:
reasons, this study did not further analyze the influence of The tensile strength of the specimen was related to its
filament feeding speed on mechanical properties. fiber content and porosity. The specimens with high fiber
contents and low porosities had high tensile strengths.
Table 3 summarizes the tensile strengths of common
polymer materials and polymer-based composites The printing layer thickness and printing spacing had
significant impacts on the fiber content. The printing
reported in the literature. The tensile strengths (along the speed did not affect fiber content but had a slight effect
fiber direction) of the specimens printed in seven schemes on the tensile strength. Different fiber contents could be
were superior to that of PEEK , the tensile strengths obtained by choosing different printing spacings and layer
[42]
(along the fiber direction) of the specimens printed in four thicknesses, and then parts with different tensile strengths
schemes were superior to that of carbon-fiber-reinforced could be obtained.
(CFR) PEEK , and all eight schemes reached or exceeded
[42]
the cortical tensile strength . Moreover, the printing The tensile strength (along the fiber direction) of the
[43]
process parameters could be adjusted to change the fiber specimen with the highest tensile strength was 209.32 ±
content and porosity to obtain implants with different 8.37 MPa, and its fiber content and porosity were 77.8%
tensile strengths to match different strength requirements. and 1.82%, respectively. This tensile strength was higher
Therefore, the continuous PGA fiber-reinforced PLA than those of cortical bone, PEEK, and short-fiber-
composites proposed in this study have good potential for reinforced PEEK, indicating that the continuous PGA
use in load-bearing degradable bone implants. fiber-reinforced PLA composites have great potential

Volume 9 Issue 4 (2023) 285 https://doi.org/10.18063/ijb.734