Systems, apparatuses, and methods are described that combine a sorbent containing a flame retardant with a substrate, which is capable of responding to temperature increases to prevent, suppress, delay the spread of, or otherwise mitigate a proximal thermal event. A flame retardant system has a flame retardant material that is incorporated into a matrical sorbent material, which is incorporated into a substrate. The matrical sorbent material is configured to release the flame retardant material upon exposure to an elevated temperature, e.g., a temperature that is greater than 300° C. in one embodiment.