Table 1.

Summary of recent studies on thermal and chemical aging of EPDM and LSR materials.

Study	Aging Type	Aging Condition	Performance Results
Thermal Aging of EPDM at 100 °C [36]	Thermal	130 °C, 145 °C, and 160 °C, with aging periods of up to 3072 h (130 °C), 768 h (145 °C), and 288 h (160 °C)	Breakdown strength decreased by 13.3% (130 °C), 21.2% (145 °C), and 22.5% (160 °C). Thermal degradation, chain breaking, and the generation of oxygen-containing groups led to reduced thermal stability. Initial decomposition temperature decreased by 11.35% after 288 h at 160 °C.
Acid and Thermal Aging of HTV Silicone Rubber [37]	Acid + Thermal	80 °C, Nitric Acid (pH = 1)	Significant cracking, reduced tensile strength from 4.58 MPa to 2.07 MPa, fracture strain reduced from 470% to 130%, thermal stability reduced by 30 °C.
Chemical Aging of EPDM [38]	Chemical (NaOH, H3PO4, NaClO)	NaOH, NaClO, H3PO4, 65 °C	Accelerated crosslinking in NaOH and H3PO4 exposure, reduction in glass transition temperature, oxidation damage. Increased crosslink density in NaClO exposure during compression.
Multi-Stress Aging of EPDM and Silicone Rubber [39]	Electrical + Mechanical	Electrical stress: 11.5 kV/mm; Mechanical stretching: 0%, 35%, 65%; Aging times: 0, 50, 100 h	For EPDM, surface damage occurred but internal properties remained stable. Mechanical properties declined by less than 20%, and the crosslinking degree remained stable.
Chemical Degradation of SR, EPDM, FKM in PEMFC Environment [40]	Chemical + Thermal	80 °C, Sulfuric Acid (pH = 3–4), Nafion® Accelerated Solution	SR experienced degradation with surface cracking and filler loss; FKM showed the best stability; EPDM showed stable mechanical properties.
Chemical and Thermal Degradation of PEFC Sealants—FKM, EPDM, Silicone Rubber [41]	Chemical + Thermal	60–80 °C, Sulfuric Acid (pH = 3.35)	EPDM showed good chemical stability. Silicone exhibited degradation in the form of weight loss. FKM showed the highest thermal stability.