Fire-retardant composite materials

Abstract

A prepreg for the manufacture of a fibre-reinforced composite material, the prepreg including:i. an epoxy-resin matrix including:a. at least one non-halogenated epoxide-containing resin which has been chemically modified with at least one of a nitrogen- and / or phosphorous-containing molecule which has been chemically reacted with the epoxide-containing molecule;b. at least one toughening additive comprising an elastomeric or thermoplastic material chemically reacted with the at least one epoxide-containing resin;c. at least one mineral filler to provide fire-retardancy; andd. at least one catalyst for curing the epoxide-containing resin; andii. a fibrous reinforcement at least partially impregnated by the epoxy resin matrix.

Description

FIELD OF THE INVENTION[0001]The present invention relates to fire-retardant fibre-reinforced composite materials and to prepregs therefor.BACKGROUND[0002]It is well known to use fibre-reinforced resin composite materials for the manufacture of structural components in a variety of industrial sectors. For some applications, the fibre-reinforced resin composite materials are manufactured from what are known in the art as prepregs—a prepreg comprises fibrous material pre-impregnated with a resin, and the amount of resin is matched to the amount of fibre so that after plural prepregs have been laid up into a mould and the resin has cured, optionally with a preliminary full wetting out of the fibrous material by the resin if the prepreg was initially not fully impregnated, a unitary fibre-reinforced composite material moulding is formed with the correct ratio of fibre to resin so that the material has the required material properties.[0003]When a composite material is used for interior p...

AI Technical Summary

Benefits of technology

[0010]The present inventors have addressed these problems of known composite materials and have aimed to provide fire-retardant fibre-reinforced composite materials, and prepregs therefor, which

Problems solved by technology

When a composite material is used for interior panel construction for mass transport applications, such as aerospace, trains, ferries, etc., in particular for the interiors of such vehicles, a fire, smoke and toxicity requirement is necessary.

Such voids would otherwise decrease the mechanical properties of the laminate.

This press-curing increases processing cost.

Secondly, the release of volatiles creates poor surface finishes that require significant filling and fairing of the cured components at a substantial additional cost.

The release of volatile components, and solvents, also results in the need to take specific health and safety precautions when using such phenolic resins.

However; they are limited in their application in primary structures due to their poor relative toughness and strength properties.

Larger, more complex shapes which are not possible with traditional construction materials are easily formed with composite materials.

Due to composites poor relative fire, smoke and toxicity properties compared to materials such as concrete and steel, the use of composites in these applications is limited.

Phenolic composite panels may be used; however, they suffer from poor mechanical properties which limit their use in primary structures.

They are however, intrinsically flammable materials and, when used unmodified, are not suitable for applications where fire, smoke and toxicity properties are required.

The two main disadvantages to this approach are high toxicity of smoke during combustion and poor health and safety characteristics associated with the material in both the uncured and cured state.