Unsintered PTFE For Wire Applications

 

FOREVERSEAL Unsintered PTFE Film is a low-density expanded PTFE (ePTFE) film engineered for wire wrapping, cable insulation, and wire harness applications. Produced from 100% virgin PTFE resin without the high-temperature sintering step, this film retains a soft, conformable structure that wraps smoothly around wires and cables of any shape.

With a standard density of 0.67 g/cm³, thickness of 0.102mm, and available widths from 4mm to 200mm, this film serves a wide range of wire and cable applications - from fine sensor wires to heavy-duty power cables. Joint-free lengths exceeding 200m ensure continuous production runs without splicing interruptions.

The unsintered expanded structure provides the key properties wire engineers need: an extremely low coefficient of friction for smooth wire movement, high dielectric strength for electrical insulation, chemical inertness for harsh environments, and a wide temperature range (-190°C to +260°C) for demanding automotive, aerospace, medical, and industrial applications.

Key Differentiator: Unlike sintered PTFE film (density ~2.15 g/cm³), unsintered expanded PTFE at 0.67 g/cm³ is 3x lighter, significantly softer, and far more conformable - making it ideal for wrapping around wires without adding excessive bulk or stiffness. It also costs less to produce, as it skips the energy-intensive sintering process.

 

Unsintered vs. Sintered PTFE - Technical Explainer 

What is Unsintered PTFE?

PTFE (Polytetrafluoroethylene) is processed in two primary forms: sintered and unsintered. The difference lies in whether the material has been heated above its crystalline melting point (~327°C) to fuse the polymer particles together:

Property	Unsintered PTFE (This Product)	Sintered PTFE
Density	0.67 g/cm³ (low, porous)	~2.15 g/cm³ (high, dense)
Structure	Soft, conformable, microporous	Rigid, solid, non-porous
Sintering	NOT heated above 327°C - retains raw structure	Heated to 370-400°C to fuse particles
Flexibility	High - wraps easily around wires	Low - stiff, must be skived to use as film
Cost	Lower - no sintering energy cost	Higher - requires high-temperature processing
Friction Coefficient	0.05-0.10 (extremely low)	0.05-0.10 (same - inherent PTFE property)
Chemical Resistance	Full - same as sintered PTFE	Full
Best For	Wire wrapping, cable insulation, gaskets	Rigid seals, machined parts, rigid liners

 

What is Expanded PTFE (ePTFE)?

The material is also described as "expanded" - meaning the PTFE has been rapidly stretched after lubrication, creating a microporous structure with millions of tiny pores per square inch. This expansion process provides several benefits:

Lower density: Expansion reduces density from ~2.15 g/cm³ to 0.67 g/cm³, making the film 3x lighter.

Higher conformability: The microporous structure makes the film softer and more flexible, allowing it to conform to irregular wire shapes.

Excellent dielectric properties: The air trapped in the pores enhances electrical insulation while maintaining PTFE's inherent dielectric strength.

Self-lubricating: The porous structure retains a lubricating effect, reducing friction between the film and the wire.

Breathable yet waterproof: ePTFE repels liquid water but allows vapor transmission - useful in applications where moisture management matters.

 

 

● PTFE(Polytetrafluorethylene)

● Expanded, natural or white

 

 

 

Thickness	0.0040"
	(0.102mm)
Tolerance	±0.00025"
	±0.006mm
Width	4 - 200mm
Density	0.67g/cm3
Tensile Strength (minimum)	12 MPa
Elongation (minimum)	50%
Joint Free Lengths	> 200m