In recent years, the bio-refining industry has developed a number of cyclic molecules with unique attributes derived from renewable carbohydrate feedstocks. Isosorbide is one such compound that has a distinctive fused bicyclic ring system that provides a scaffold for the development of novel bio-based resin systems. We synthesized isosorbide-methacrylate (IM) by the direct esterification of isosorbide using highly reactive species such as methacryloyl chloride or methacrylic anhydride and a base catalyst. IM is a low viscosity (157 cP) cross-linking resin that free radically reacts to form a thermoset polymer with extent of cure at 85%. The resulting polymer has a T g greater than 240 C and main degradation temperature of $400 C. Mechanical test results showed that IM had a modulus of $4 GPa and strength of 85 MPa. These thermal and mechanical properties show that IM has a significantly higher temperature operating window than any known vinyl ester resin and has similar performance to expensive high temperature epoxy resins. As such, this material has good potential for use in composite applications where a moderate to high temperature free radical cured polymer matrix is needed.

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The microstructures of Al-Mg alloys with greater than 3wt.% Mg can sensitize leaving the material susceptible to intergranular corrosion (IGC); sensitized microstructures are identified by the amassing of phase precipitates at grain boundaries. Friction stir processing (FSP) has previously been shown to increase the corrosion resistance of sensitized Al-Mg alloys through break-up of the continuous network of phase particles [1]. In this study, multi-pass FSP is applied to a sensitized 5456-H116 aluminum plate and the resulting microstructure is linked to local mechanical properties (0.2% yield strength, ultimate tensile strength, and elongation) obtained using micro-tensile specimens extracted transversely across the FSP region. In the FSP region, the original sensitized microstructure becomes unsensitized; the unsensitized region is not limited to the friction stir zone but extends outward several mm into the base material. Though the sensitized microstructure is removed, the mechanical testing within the affected area shows the strength and elongation decrease and increase respectively from H116 temper to O temper levels. The previously sensitized microstructure is not observed to have negatively affected the mechanical properties

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