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Materials that can dynamically change their properties to better adapt to the local environment have potential utility in robotics, aerospace, and coatings. For some of these applications, most notably robotics, it is advantageous for these responsive materials to be highly compliant in an effort to provide dynamic changes in adhesion and mechanical damping within a broad temperature operational environment. In this report, non-aqueous, highly compliant shapememory polymer gels are developed by incorporating a low density of chemical cross-links into a physically cross-linked thermoplastic elastomer gel. Chemical cross-linkers were evaluated by varying there size and degree of functionality to determine the impact on the mechanical and adhesive properties. As a result of the chemical cross-linking, the gels exhibit modulus plateaus around room temperature and at elevated temperatures above 100 °C, where the thermoplastic elastomer gel typically melts. The materials were designed so that moduli in the plateaued regions were above and below the Dahlquist criteria of 4×10 4 Pa, respectively, where materials with a modulus below this value typically exhibit an increase in adhesion. The shape memory polymer gels were also integrated into fiber-reinforced composites to determine the temperaturedependent changes in mechanical damping. It is anticipated that this work will provide insight into materials design to provide dynamic changes in adhesion and damping to improve robotic appendage manipulation and platform mobility.

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Realization of property enhancements inherent to the presence of nanoparticles continues to be a challenge for the production of bulk nanocomposite materials with commercially available techniques. This study combines twin-screw compounding with surface modification of SiO 2 nanoparticles to enable targeted dispersion in a SEBS block copolymer. Production of these composites with high levels of well-dispersed particulates aims to leverage aggregation for production of hierarchical structure. The aggregation state of the particles as well as the level of order in the block copolymer morphology was determined through USAXS and TEM. Particles coated with ligands miscible with the end-blocks of the BCP (minority component) increased dispersion at all loading levels observed up to 10 vol%. Ligands employed to increase miscibility of the nanoparticle with the mid-block (majority component) resulted in large aggregates for all loadings without disturbance of the BCP morphology.