Cornerstone Research Group, Inc. (CRG) proposes to design and develop a space-qualifiable cyanate ester elastomer for application in self-deployable space structures and future aircraft systems. Having already demonstrated the feasibility of the current cyanate ester shape memory polymer (SMP) as a space-qualifiable material, CRG proposes to refine its existing cyanate ester SMP to provide the flexibility necessary for self-deployable space structures. Working extensively on deployable structure systems for NASA and DoD projects (see section 5.2), CRG has demonstrated the feasibility of self-deploying structures by using surrogate styrene-based systems. CRG now proposes to develop new cyanate ester resins, incorporating the siloxane moiety in the monomer or polymer network, to provide NASA with a material combining the flexibility of siloxanes with CRG's space-qualifiable cyanate ester SMP. CRG's work with DoD and commercial aerospace customers has also helped to identify the proposed material as a durable, lightweight alternative to current state-of-the-art aircraft systems. CRG's innovative approach to the development of space-qualifiable cyanate ester elastomer will provide NASA with a low-cost, space-durable, and flexible material for application in self-deployable space structures and future aircraft systems.