The Shape of Stability: Processing History and Functional Response in Thermosets, with a Focus on Filled Epoxies

Assessing stability in filled epoxies requires specifying the intended material state and processing history. This structured narrative review examines local structural stabilization, physical support during fabrication, and functional retention, drawing on a broader corpus of 63 publications on filled thermosets. Multiple correspondence analysis (MCA) organizes evidence profiles from 60 empirical publications with complete codes by mapping co-occurring processing comparisons, structural observations, stabilization indicators, and functional-assessment stages. Carbon nanotube and clay studies show that structural plateaus indicate limited change in measured descriptors within observation windows, rather than global filler arrest or preservation of initial dispersion. Matrix cure markers cannot substitute for direct structural observations. In reduced graphene oxide composites, faster local network development observed optically does not necessarily correspond to higher conductivity in separately cured bulk specimens. In silica-filled epoxies, thermal programs must balance resistance to deformation against cure advancement; rheological evidence alone does not establish shape retention during printing. Electrical advantages established after one processing program can diminish after further heating, while recovery on cooling differs from retaining performance at elevated temperature. Meaningful stability comparisons therefore require observables, comparators, and readout conditions appropriate to the intended material state and processing sequence; transfer to other histories requires separate assessment.