Integral composite structure incorporating multiple resin-based systems and method of manufacture

A composite structure comprising:

• a three-dimensional woven fabric structure having a first fabric layer and a second fabric layer spaced apart from the first fabric layer, said layers connected by intermediate fibers forming a portion of the three-dimensional woven fabric structure, said fibers defining voids in the space between the first and second layers;
• a first cured resinous material penetrating the first layer of the woven fabric structure;
• a second cured resinous material penetrating the second layer of the woven fabric structure;
• wherein the first resinous material and the second resinous material are chemically incompatible;
• and
• wherein said first and second cured resinous materials also cover at least a portion of the intermediate fibers and meet, but do not substantially overlap, to form a resin interface at a junction point on said fibers.

A process for preparing a composite structure comprising the steps of:

• obtaining a three-dimensional woven fabric structure having a first fabric layer and a second fabric layer spaced apart from the first fabric layer, said layers connected by threads forming a portion of the three-dimensional woven fabric structure, said threads defining voids in the space between the first and second layers;
• placing said first layer in contact with a first resinous material and allowing the first resinous material to penetrate the first layer of the woven fabric structure;
• placing said second layer in contact with a second resinous material, where said second resinous material is different from said first resinous material, and allowing the second resinous material to penetrate the second layer of the woven fabric structure;
• and
• curing said first and second resinous materials.