Thermoplastic Veils & Mats

Our latest range of thermoplastic nonwovens, which includes materials such as PPS (polyphenylene sulfide), PEI (polyetherimide), PEEK (polyether ether ketone) and Nylon offers ideal compatibility with thermoplastic resin systems as well as delivering properties such as high temperature resistance or interlaminar toughness in composites. As with all products in our Optiveil® and  Optimat® ranges, TFP's thermoplastic materials demonstrate excellent resin uptake and are compatible with most resin systems, making them suitable for use in all common composite fabrication techniques. 

Properties:    

  • High temperature resistance
  • Flexible pre-forms
  • Ideal compatibility with thermoplastic resin systems
  • Excellent resin uptake

 

Areal weight:   4 g/m² up to 200 g/m²

Binders:            Cross-linked polyester and polyester

Typical applications: 

  • Lightweight Optiveil®veils can be used as carrier or support for materials such as adhesives.
  • Lightweight thermoplastic veils can also improve interlaminar fracture toughness in composite structures, this is discussed in more detail below.
  • Veils made using precise blends of thermoplastic with carbon or glass fibre can be manufactures to generate a thermoformable nonwoven.
  • Thermoplastic pre-forms utilising the combined attributes of flexibility and ease of processing offer the capability to produce complex shapes without advanced tooling systems. 

 

Focus on improving interlaminar fracture toughness:

THE CHALLENGE:

Fibre reinforced composites, comprising of a layup of carbon reinforcement fabrics infused with epoxy resin, can exhibit low fracture toughness. In service these composite materials can be prone to interlaminar failure under both Mode-I and Mode-II loadings or in scenarios such as tool dropping (during maintenance) when the composite experiences out-of-plane low energy impact. the presence of interlaminar damage can be very detrimental to the delamination fatigue properties of a fibre reinforced composite and ultimately compromise the mechanical performance of the structure. 

THE SOLUTION:

Recent studies using our nonwovens have reported a proven increase in the interlaminar fracture toughness of a composite. The improvement is achieved by interleaving our lightweight thermoplastic veils between the reinforcement plies and then infusing the structure with resin. We have developed an extensive range of thermoplastic veils with this specific purpose in mind; these include Polyimide, Polyether ether ketone (PEEK), Polyphenylene sulfide (PPS), Poly etherimide (PEI), Polyamide and Polyester. The studies have measured the effect of interleaving various veil types, relative to a control, for both Mode-I and Mode-II testing. The data, summarized overleaf, demonstrates that a significant improvement in the interlaminar fracture toughness can be achieved.

Data from these recent studies indicate that interleaving TFP's thermoplastic veils can engineer a significant improvement in the Mode-I and particularly Mode-II fracture toughness, for the latter an improvement of up to 350% & 430% (for intiation & propagation respectively) can be achieved. The veil type used dictates the level of improvement observed, PEEK and PPS are the most effective, but other thermoplastic veils can be selected based on the performance required.

The data is taken from: V.A. Ramirez, P.J. Hogg, W.W. Sampson - The influence of the nonwoven veil architectures on interlaminar fracture toughness of interleaved composites, Composites Science and Technology 110 (2015) 103-110.

 

Our veils and mats are available in rolls from as narrow as 5 mm up to 1650 mm in width. We also offer the capability to supply materials in sheeted form or as cut shapes. Please contact us to learn more our materials and capability, we would welcome the opportunity to discuss your specific requirements.