Development of Bio-Composites from Milkweed Fibers Using Air-Laid Spike Process for Automobile Dashboard Applications

Area of Science:

• Materials Science
• Polymer Science
• Automotive Engineering

Background:

• Natural fibers like milkweed offer sustainable alternatives in composite materials.
• Polylactic acid (PLA) is a biodegradable polymer suitable for various applications.
• Automotive interiors require materials with excellent thermal insulation and acoustic properties.

Purpose of the Study:

• To investigate the reinforcement of polylactic acid (PLA) bio-composites using milkweed fibers.
• To evaluate the suitability of these bio-composites for automotive dashboard applications.
• To analyze the impact of fiber layering on material properties.

Main Methods:

• Milkweed fibers were blended with PLA fibers (75:25 ratio) via air-laying.
• Multiple layers of nonwoven material were compression molded to create bio-composites.
• Properties evaluated included density, microstructure, thermal conductivity, sound transmission loss (STL), mechanical properties, and dynamic mechanical analysis (DMA).

Main Results:

• Milkweed fibers partially collapsed during high-pressure molding, without negatively impacting properties.
• Bio-composites with more layers showed decreased thermal conductivity (5%) and increased STL (19%).
• Increased layering significantly enhanced specific flexural strength (160%) and modulus (335%), indicating a superior mechanical-property-to-density ratio.

Conclusions:

• The developed milkweed-PLA bio-composites meet automotive dashboard specifications.
• The bio-composite offers a promising sustainable material for automotive interiors.
• Optimized layering is crucial for balancing thermal, acoustic, and mechanical performance.