Innovative AFR-VARTM resin and HTVARTM processing

High Temperature Polymer Matrix Composites (HTPMCs) are needed in advanced aerospace systems but their use is limited by manufacturing cost. Vacuum-Assisted Resin Transfer Molding (VARTM) produces low cost composites but currently isn't used with HTPMC's due to high resin viscosity even at elevated temperatures. Infoscitex (IST) proposes to create AFR-VARTM resin via addition of compatible reactive diluents (RDs) to commercially available AFR-RTM. RD's in the system will significantly reduce resin viscosity during heated VARTM and will lead to additional crosslinking upon cure to create a strong hydrophobic resin matrix with enhanced hot/wet performance without evolution of volatiles. Reduced resin viscosity in combination with compatible, functional sizing will facilitate resin wet-out and rapid wicking into the fabric perform. Microcracks will be prevented by blending mono- and difunctional RD which cures to a more linear molecular structure with less shrinkage and lower stress. Phase I thermal, physical and mechanical evaluation on multiple formulations will lead to down selection of the AFR-VARTM system and processing conditions. Phase II includes material and process optimization, manufacturing scale up and will culminate in the fabrication of a sub-scale demonstration article. Program partners include UDRI, Maverick, Hydrosize, Fabric Development, and Pratt & Whitney.