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Cornerstone Research Group, Inc. (CRG) has developed processes to make molds for casting and mandrels for filament winding composite parts from novel shape memory polymers (SMPs). For external molding, the SMP tooling system is capable of being thermally formed into a precise negative image of a master part, cooled, and made to retain the new shape. For filament winding mandrels, internal SMP mandrels can be used and easily extracted after curing. CRG has developed the ability to fabricate SMP materials from a wide range of polymer systems. Veriflex™, the trademark name for CRG's shape memory polymer resin systems, functions on thermal activation customizable from -20°F to 520°F. These materials can withstand the elevated temperatures that are needed to cure composite parts without deformation and offer a gentle, simple demolding process. After the composite part has cured, the mold is raised above the T g , which allows it to retract to its memory shape. SMP tooling processes provide the opportunity to mitigate the drawbacks of traditional fabrication techniques for advanced composite parts. This tooling system also possesses versatility in size variations, including being capable of micro (nanometers) to macro (meters) replication.

Cornerstone Research Group Inc. (CRG) has developed environmental exposure tracking (EET) sensors using shape memory polymers (SMP) to monitor the degradation of perishable items, such as munitions, foods and beverages, or medicines, by measuring the cumulative exposure to temperature and moisture. SMPs are polymers whose qualities have been altered to give them dynamic shape "memory" properties. Under thermal or moisture stimuli, the SMP exhibits a radical change from a rigid thermoset to a highly flexible, elastomeric state. The dynamic response of the SMP can be tailored to match the degradation profile of the perishable item. SMP-based EET sensors require no digital memory or internal power supply and provide the capability of inexpensive, long-term life cycle monitoring of thermal and moisture exposure over time.This technology was developed through Phase I and Phase II SBIR efforts with the Navy. The emphasis of current research centers on transitioning SMP materials from the lab bench to a production environment. Here, CRG presents the commercialization progress of thermally-activated EET sensors, focusing on fabrication scale-up, process refinements, and quality control. In addition, progress on the development of vapor pressure-responsive SMP (VPR-SMP) will be discussed.