Temperature Responsive PBT Bicomponent Fibers for Dynamic Thermal Insulation.

Area of Science:

• Materials Science
• Textile Engineering
• Polymer Science

Background:

• Thermoresponsive materials offer adaptive properties for textiles.
• Polybutylene terephthalate (PBT)-based bicomponent fibers can exhibit self-crimping behavior.
• Previous studies explored polypropylene fibers for similar applications.

Purpose of the Study:

• To fabricate and characterize thermoresponsive self-crimping PBT-based bicomponent fibers.
• To optimize fiber properties for use in adaptive single insulating layers.
• To evaluate the thermal responsiveness of nonwoven battings made from these fibers.

Main Methods:

• Melt-spinning of PBT-based bicomponent fibers.
• Controlled drawing processes to influence fiber microstructure and properties.
• Mechanical and thermal property testing.
• Fabrication and testing of nonwoven battings.

Main Results:

• Self-crimping behavior was observed in PBT-based bicomponent fibers due to mismatched modulus and coefficient of thermal expansion (CTE).
• An optimal draw ratio of 2.33 was identified for maximizing self-crimping behavior and achieving desirable mechanical/thermal properties.
• Increasing the draw ratio beyond 2.33 did not necessarily enhance self-crimping.
• Nonwoven battings demonstrated comparable thermoresponsive behavior to existing polypropylene-based fibers in the -20 °C to 20 °C range.

Conclusions:

• PBT-based bicomponent fibers can be effectively engineered for thermoresponsive self-crimping.
• The study provides insights into optimizing fiber microstructure for enhanced thermal adaptation in textiles.
• These fibers show potential for developing advanced wearable insulation for commercial and defense applications.