Description: Reversible adhesives are an attractive option for assembly and disassembly of reconfigurable space structures due to the simplicity of the fastening concept. Space frame construction technologies have in the past relied on metal-based unit elements ( or recently with fiber composite elements), which are either permanently joined, or connected via labor-intensive and difficult to automate joint mechanisms. NASA is also interested in thin-walled, deployable structural concepts that can be folded/rolled under strain for launch and deployed in orbit. However, the thin composites structures would experience a wide temperature range (300°C) and high folding deformation, which need to be overcome by using high creep resistance resins. Aromatic thermosetting copolyesters (ATSP) is a new family of thermoset polymers with wide temperature ranges (Tg up to 310°C). By supplying heat and pressure between ATSP surfaces, ATSP can be bonded together as an adhesive with reversible capabilities - demonstrated over 50 cycles and over temperature ranges relevant to the LEO environment. In this proposal, there are two main objectives: 1) manufacturing of Collapsible Tubular Mast and Corrugated Rollable Tubular Booms and 2) in-space reversible joining on arbitrary surfaces (box-on-panel) and tubular truss structures. For target 1, ATSP and team partner Cutting Dynamics will manufacture thin-ply ATSP/CF composites which will be bonded to form a rollable tubular structure; and we will apply ATSP adhesive to bond PI/CF thin composite to form the structure. For target 2, we will select the best heating method from induction, microwave and infrared to supply heat for reversible bonding process. In the development, we will carry out a bonding parameters, and bonding quality study to ensure best performance. At the end of the project, we will deliver physical demonstration examples and a portable bonding toolkit as well as detailed use guides for using ATSP's reversible adhesive system.

Benefits: ATSP's reversible adhesive resins enable several concepts useful to mission planners: Assembly and reconfiguration of payload modules and element-by-element assmbly while on-orbit. This capability enables the construction, expansion, and reconfiguration of persistent asset structures. Rollable composite truss and boom structures that can be directly assembled on earth or on-orbit presents opportunities for assembly of complex 3D structures and stiffer simple 1D booms that will provide new options for development of persistent platforms.

ATSP-based adhesives are applicable for Aerospace, Automotive, Space Exploration, and Energy. ATSP-based adhesives could enable rapid on-demand high temperature adhesive bonds for many product spaces. ATSP-based composites can be used for high temperature structural applications. ATSP-based composites are fully compatible with ATSP adhesives and could enable step-wise assembly of large structures