Mold release films: Critical to aircraft safety and performance

Mold release films: Critical to aircraft safety and performance

by Andreas Faber

Behind the scenes, ETFE, PTFE and FEP-based mold release films play a vital role in aircraft and aerospace craft manufacture.

Why Composite Structure Molding?

In essence, composite structure molding improves the strength-to-weight ratio and resistance to corrosion and fatigue of the materials used in the aircraft. In the context of safety protocols crucial to successful air travel, it's all about offering the cleanest, most consistent release performance possible when manufacturing the parts used in the craft’s construction.

In the air, the failure of a structural part is catastrophic. Composite solutions backed by fluoropolymer-based mold release films are commonplace in structural sections of an aircraft such as the fuselage, wing, tail, nose sections, and even complete airplanes.  

Airplane Engine
VERSIV Films can be used as process aids to facilitate structural composite molding.
red fep release film closeup
VERSIV FEP Films boast good tensile strength and high resistance to wear and tear.

How do Composite Solutions Help?

Composite parts design requires materials that provide the highest performance levels in the composite molding industry. Advances in process materials include specially designed fluoropolymer-based adhesive tapes that break the flash overage created during vacuum component bonding and conform intimately to various surfaces without leaving a silicone oil residue that may contaminate and potentially introduce scrap to a molding operation. 
Also used in composite molding are textured release films and coated fabrics that effectively debulk the composite layup before curing. The texture on the surface of these films allows pathways for air to travel to achieve maximum part density more efficiently. 

Engineers Working On Airplane Engine

Contributing to safer air travel 

Composite parts are superior to traditional metals, including aluminum, due to higher strength, lower weight, and excellent resistance to flex fatigue and exposure to environmental extremes such as heat, cold, humidity, and pressurization. 

Poor-performing release liners can impact production yields, resulting in undesirable surface irregularities that may deviate from the component's end-use tolerances. 
Mold-release films contribute to achieving high-quality surface finishes on aircraft components. They provide a smooth and uniform release, minimizing imperfections such as surface defects, scratches, or blemishes. A flawless surface finish is crucial for aerodynamics, as it helps reduce drag and maintain the aircraft's performance efficiency.
The properties inherent in composite materials like FEP films are essential. FEP films boast good tensile strength with high resistance to wear and tear due to their elongation capabilities and tear- and abrasion-resistant properties.  

etfe release film

Withstanding high temperatures a non-negotiable for aircraft manufacture 

Films such as VERSIV ETFE Pigmented fluoropolymer film that can handle temperatures of up to 356˚F (180˚C) reduce the risk of foreign object contamination occurring downstream during composite structure manufacture. 

This application would not exist without this composite material as those materials require temperature stability to be backed at 180°C+ in an autoclave for 24hrs. 
Aircraft and aerospace craft are much safer due to the properties provided by fluoropolymer-based release films. Alternative materials are, in effect, compromising that safety.