As solid-state battery and EV markets surge, demand for UL 94 V-0-rated potting compounds grows. Yet a common misconception persists: “Silicone is heat-resistant, so it must be flame-retardant.” Reality tells a different story.
While methyl silicones have high flash points (>300°C), they decompose under UL 94’s 600–800°C flame into volatile cyclics (D4/D5) and flammable hydrocarbons. These gases prolong burning and may cause flaming drips—failing V-0 despite a robust base resin.
Not all silicones are equal. Phenyl-modified or reactive types show better thermal stability. Crucially, final-formulation testing is non-negotiable. One electronics adhesive developer shared: “We passed V-0 with pure resin—but failed after adding 2% standard silicone oil.”
