Polyurethane Foam, Synthesis, Plastics Britannica

Specifications for caulking of foam strips in photovoltaic panels

Solargain is a 100% solids, durable, nonconductive butyl edge sealant designed specifically for thin film photovoltaic module manufacturing. PSET LP02 is desiccated to trap moisture before it reaches the active cell area. Suitable for modules tested to UL 1703, IEC 61646 and IEC 61730. [PDF Version]

What is the foam inside the photovoltaic panel called

In photovoltaic panels, it prevents overheating, which can reduce efficiency, while in solar thermal panels, it aids in retaining the captured heat, enhancing energy output. [PDF Version]