Improved epoxy‐amine matrices for composites

The physical and mechanical properties of epoxy‐amine matrices can be improved by the use of additives known as epoxy fortifiers. The tensile strength of a typical aminecured epoxy increased from 82 MPa to 123 MPa, the tensile modulus form 2.5 GPa to 4.1 GPa, and the tensile test specimens also failed in a ductile fashion. The improvements in matrix properties translated into improved performance for filament‐wound and cloth‐reinforced composites. For example, the transverse moduli and compression strengths of carbon fiber/epoxy filament‐wound tubes and plates increased at least 20 percent with the addition of fortifiers, while the compression strength of glass cloth/epoxy laminates increased by up to 41 percent.