Characteristics of Polyester Fiber for Shoe Insoles
- Jul 21
- 2 min read
Polyester fiber is a durable and resilient synthetic material that is gaining attention as a potential insole material for footwear.
While EVA (Ethylene-Vinyl Acetate) foam and PU (Polyurethane) foam have traditionally been used for shoe insoles, nonwoven polyester fiber boards are emerging as an alternative due to their environmental friendliness and long-lasting performance.
Physical and Functional Properties of Polyester Fiber Insoles (Advantages)
Excellent Durability and Shape Retention : Polyester fiber insole boards exhibit strong tensile strength and abrasion resistance, maintaining their shape and performance over time without deformation.
Shock Absorption and Elasticity : Although the nonwoven polyester board appears rigid, its fine porous structure absorbs pressure, providing a cushioning effect. With proper compression molding during manufacturing, the material can serve as a buffer to reduce impact during walking.
Breathability and Moisture Control : While polyester fibers themselves are not highly hydrophilic, the nonwoven structure allows for breathability through air channels.
Hygiene and Antimicrobial Properties : As a synthetic material, polyester is naturally resistant to mold and bacteria. Additional antimicrobial treatments can further enhance the hygiene of the insole.
Disadvantages and Considerations of Polyester Fiber Insoles
There are certain limitations and considerations when using polyester nonwoven insoles:
Limited Cushioning and Need for Additional Padding : Polyester fiber boards alone do not provide the immediate plush feel that EVA or PU foams offer. While they have some elasticity and shock absorption, the soft cushioning effect is limited. For this reason, final insole products often incorporate dual-layer constructions, adding PU foam, latex, or memory foam layers on top of the polyester board, or attach additional pads at the heel or arch areas.
Flexibility and Conformability : Polyester fiber boards are manufactured as flat, rigid sheets—similar to cardboard—making them less adaptable to the foot’s 3D contours compared to foam materials. Once molded, they provide firm support similar to carbon insoles but are difficult to reshape. If not molded correctly at the start, adjustments are challenging.
Limitations in Shock Absorption : As mentioned, fiberboards provide moderate shock absorption, but not to the extent of high-deformation foams. For high-impact activities such as running, it is recommended to use additional shock-absorbing components (e.g., EVA pads) in conjunction with the polyester board.
In summary, polyester fiber insoles offer excellent support and durability but may require structural enhancements or post-processing (e.g., molding, antimicrobial treatment) to improve cushioning and fit compared to pure foam-based insoles.
DK FIBER supplies polyester staple fibers with a 3D crimp, optimized for fiber insole board manufacturing.
Visit the link below to learn more about our fiber solutions.
