Creep-Resistant Aromatic Polyester Thermosets for Thin-Ply Composites

For deployment of future space structures, volume-minimized methods of rolling/folding carbon fiber composites during launch may be attractive. Due to the high strain and potential elevated temperatures during launch, there is concern about creep and therefore distortion of the composite member. ATSP Innovations and team partner Texas Aamp;M University propose a unique thin ply composite for inflatable and rollable/foldable space structure concepts. ATSP Innovations has developed a new family of high performance resins called Aromatic ThermoSetting coPolyesters, which have Tg ranging from 174-310C and high thermal stability. In Phase I, we seek to produce a modified resin system with a lower temperature cure profile and fabricate this resin into thin-ply ATSP-carbon fiber reinforced composites. Initially, a matrix of formulated resins and catalyst concentrations will be synthesized and examined in terms of themomechanical properties. ATSP and Texas Aamp;M will characterize and model the resins creep and stress relaxation properties. The best performing resin in terms of thermomechanical properties, viscosity, and cure profile will be selected for prepregging into thin-ply composites and cured into coupons for further creep and stress relaxation experiments. A film adhesive interlayer useful for production of the desired thin-walled members will also be developed and initially demonstrated. A nonlinear thermo-viscoelastic constitutive model will be formulated for the general anisotropic material as determined from experiments. This will be coupled with a microstructural model and structural model to predict behavior of thin-ply composite. In Phase II, ATSP Innovations will also investigate appropriate fabrication methods for producing rollable composite members as well as key metrics for their viability in space applications.nbsp;