Definition: Bicomponent fiber is comprised of two polymers of different chemical and / or physical properties extruded from the same spinneret with both polymers within the same filament.
Bicomponent Fiber Capabilities
Bicomponents can provide:
- Thermal bonding
- Self bulking
- Very fine fibers
- Unique cross sections
- The functionality of special polymers or additives at reduced cost
Common Bicomponent Configurations
Most commercially available bicomponent fibers are configured in a sheath / core, side-by-side, or eccentric sheath / core arrangement.
Sheath / Core Side by Side Eccentric Sheath / Core
Advantages of Bicomponent Thermal Binder Fibers
- Uniform distribution of adhesive
- Fiber remains a part of structure and adds integrity
- Customized sheath materials to bond various materials
- Wide range of bonding temperatures
- Cleaner, environmentally friendly (no effluent)
- Lamination / molding / densification of composites.
Common Polymer Combinations in Bicomponent Thermal Binder Fibers
- Polyester Core (250C melt point) with Copolyester Sheath (melt points of 110C to 220C)
- Polyester Core (250C melt point) with Polyethylene Sheath (130C melt point)
- Polypropylene Core (175C melt point) with Polyethylene Sheath (130C melt point)
Self Bulking Bicomponent Fibers
- Created most often with side-by-side or eccentric cross section
- Variation in orientation across the fiber causes crimping due to differential shrinkage or strain with applied heat or relaxation.