| EPDM Rubber Gasket | Module frame perimeter, mounting interfaces, junction-box sealing in selected designs | Approximately −40°C to +120°C; formulation and compression design affect the actual rating | Very good resistance to sunlight, ozone, rain, and humidity | Good long-term outdoor durability; cost-effective; flexible; widely available; suitable for many static seals | Not recommended for continuous contact with petroleum-based oils, fuels, or many hydrocarbon fluids | Framed modules, rooftop systems, utility-scale projects, and general outdoor PV sealing | Compression set, dimensional tolerance, joint design, surface finish, hardness, and resistance to water ingress |
| Silicone Rubber Gasket | Junction boxes, cable exits, connectors, frame seals, and high-temperature sealing locations | Commonly approximately −50°C to +200°C, depending on grade and design | Excellent resistance to UV radiation, ozone, moisture, and temperature cycling | Wide temperature capability; strong aging performance; remains flexible over a broad temperature range; good electrical insulation | Usually higher cost; relatively lower tear and abrasion resistance than many organic rubbers; may have higher gas permeability | Hot climates, cold climates, high-reliability junction boxes, and components exposed to thermal cycling | Grade suitability, compression set at operating temperature, tear strength, adhesion compatibility, and electrical insulation properties |
| TPE or TPV Gasket | Co-extruded frame seals, snap-fit channels, replaceable perimeter gaskets, and customized profiles | Typically approximately −40°C to +100°C or higher, depending on polymer family | Good to very good when a UV-stabilized outdoor grade is selected | Can be extruded or molded; recyclable in some production systems; consistent dimensions; easy installation; supports complex profiles | Performance varies significantly by formulation; some grades show creep or compression set under prolonged heat and load | High-volume module production, lightweight profiles, automated assembly, and applications requiring custom geometry | Outdoor UV rating, compression set, creep resistance, profile dimensional stability, weld or corner quality, and recyclability claims |
| Neoprene (CR) Gasket | Electrical enclosures, junction-box seals, cable-entry seals, and selected frame applications | Approximately −35°C to +100°C for many general-purpose grades | Good resistance to weathering, ozone, and moderate sunlight exposure | Balanced mechanical strength; good resistance to abrasion and moderate oils; useful for rugged enclosure seals | Generally less resistant to long-term heat and UV aging than high-grade silicone or EPDM; material selection must match the exposure | Robust electrical enclosures, mechanical protection areas, and installations with moderate oil or abrasion exposure | Actual weathering grade, plasticizer migration, compression set, oil compatibility, and long-term outdoor test results |
| Fluorosilicone Gasket | Specialized junction boxes, connectors, and seals exposed to fuels, oils, or aggressive fluids | Often approximately −60°C to +175°C, depending on grade | Excellent UV, ozone, and weathering resistance | Combines broad silicone temperature performance with improved resistance to many fuels and hydrocarbon-based fluids | High material cost; limited need for ordinary PV environments; mechanical strength may require careful design | Specialized PV equipment near industrial fluids, transport applications, or demanding chemical environments | Chemical compatibility, compression set, fluid immersion results, temperature cycling, and justification for the premium material |
| Polyurethane (PU) Gasket | Protective enclosure seals, cushioning interfaces, and selected custom-molded applications | Commonly approximately −40°C to +90°C; grade-specific limits are important | Variable; outdoor use generally requires a UV-stabilized aliphatic grade rather than a standard aromatic grade | High abrasion resistance; good tear strength; available in solid and foam forms; useful for cushioning and impact protection | Some formulations hydrolyze or discolor under heat, moisture, and sunlight; not every PU grade is suitable for long-term outdoor PV use | Protected enclosures, impact-prone areas, and custom seals where abrasion resistance is more important than maximum temperature capability | UV-stabilizer type, hydrolysis resistance, water absorption, compression recovery, and accelerated aging performance |
| Foam Tape or Closed-Cell Foam Gasket | Low-pressure frame interfaces, enclosure covers, cable-entry interfaces, and secondary weather seals | Typically approximately −40°C to +90°C, depending on foam chemistry and adhesive system | Good when the foam, adhesive, and facing are all rated for outdoor exposure | Fast installation; conforms to uneven surfaces; provides cushioning and vibration isolation; available in various thicknesses | Usually lower resistance to sustained compression, peel forces, solvents, and extreme temperatures than solid rubber seals | Secondary sealing, low-pressure weather barriers, and assemblies with moderate dimensional variation | Closed-cell structure, water absorption, adhesive shear strength, compression recovery, edge sealing, and exposure to condensation |