Novel hydrophobic, tough, and high temperature matrix resins for polymer composites

The improved thermal, mechanical, and environmental properties of a number of matrix resins are described. Chlorinaled epoxy resins were found to adsorb much less water than their non-chlorinated analogues, and showed improved hot-wet properties. Custom synthesised thermoplastic toughening agents were used to improve the fracture toughness of a tetrafunctional epoxy resin system. Substantial increases in K^ and G^ were achieved, with minimal loss of temperature performance. A number of highly functionalised epoxy monomers, with up to eight epoxy groups each, were prepared. The resulting cured matrixes were found to have glass transition temperatures in excess of 300(omicron)C. Blends of cyanate ester and bismalcimide were investigated as tough, high temperature performance matrixes. Addition of bismaleimide to cyanate ester resulted in an increase in fracture toughness. Dynamic mechanical analysis showed two distinct glass transitions, suggesting that the material has a two phase morphology such as an interpenetrating network.