# Research on the Preparation of Polylactic Acid/Bamboo Fiber Composite Materials and Their 3D Printing Process

## TL;DR

Researchers developed a strong, sustainable composite material using bamboo fiber and polylactic acid, suitable for 3D printing orthopedic braces.

## Contribution

A scalable method for enhancing natural fiber composites with silane treatment and optimizing 3D printing parameters for orthopedic applications.

## Key findings

- Bamboo fiber-reinforced PLA/PBAT composites achieved an impact strength of 7.7 kJ/m² at 10 wt.% fiber content.
- Silane treatment increased impact strength to 11.3 kJ/m², improving fiber–matrix adhesion.
- Foot braces printed at 35 mm/s showed structural integrity and high impact strength.

## Abstract

What are the main findings?
Bamboo fiber-reinforced PLA/PBAT composites achieve high impact strength.Silane treatment enhances fiber–matrix dispersion, boosting composite toughness.Foot braces fabricated at 35 mm/s demonstrate high impact strength and structural integrity.

Bamboo fiber-reinforced PLA/PBAT composites achieve high impact strength.

Silane treatment enhances fiber–matrix dispersion, boosting composite toughness.

Foot braces fabricated at 35 mm/s demonstrate high impact strength and structural integrity.

What are the implications of the main findings?
Provides a scalable interfacial modification strategy for natural fiber composites.Expands bio-based material applications in orthopedic braces.Establishes a process for high-performance 3D-printed braces, advancing personalized medicine.

Provides a scalable interfacial modification strategy for natural fiber composites.

Expands bio-based material applications in orthopedic braces.

Establishes a process for high-performance 3D-printed braces, advancing personalized medicine.

The increasing need for lightweight, personalized, and sustainable orthopedic braces has motivated the development of bamboo fiber (BF)-reinforced polylactic acid (PLA) composites. In this study, BF/PLA composites were prepared by melt blending. The effects of polybutylene adipate terephthalate (PBAT) toughener, BF content, and a silane coupling agent on the mechanical properties were evaluated, along with their suitability for 3D printing foot braces. The results showed that at a PLA/PBAT mass ratio of 85/15 and a bamboo fiber content of 10 wt.%, the impact strength of the composite reached 7.7 kJ/m2. Silane treatment of BF further improved the impact strength, with a maximum value of 11.3 kJ/m2 achieved at a silane/BF mass ratio of 2/98. The optimized composite exhibited good printability across nozzle temperatures of 190–210 °C. Printing speed significantly influenced the process; a speed of 35 mm/s enabled successful fabrication of the foot brace, whereas higher or lower speeds led to model collapse due to overheating or cracking caused by insufficient interlayer adhesion. This study successfully developed a bamboo fiber-reinforced PLA composite suitable for 3D printing of orthopedic braces and identified the optimal 3D printing process parameters.