Wouter,

Its not really correct to say that it is just GRP with a different resin.

The properties of a composite aren't just the sum of their parts.

To take the classic, glass fibres in epoxy as an example. Both glass fibres and epoxy are terribly brittle on their own and pretty much useless as an engineering material. It is the way they are combined that makes them a useful composite (or material).

It may not be right to call it a new material (lets say a new composite), but its more than just a new resin, as the impact resistant properties come from the way this composite forms during processing.

As John Alani points out you could make a hull out of anything that absorbs resin, but you may not get the properties you expect.

People have been trying to combine carbon and aluminium for some time with varying degrees of success, it is very difficult to get them to process together but when they do you get a great composite. This is starting to be used in Formula one.

Gareth
www.fourhulls.com