Low-Stress, High-Clarity Silicone Gel for Optical and Electronic Assembly
When assembling delicate optical instruments or sealing sensitive microelectronics, material choice directly affects long-term reliability. IOTA GNJ 3128H phenyl silicone gel delivers low mechanical stress while remaining clear and flexible across a broad service temperature range from -59°C to 200°C.
This two-part silicone system is formulated for room-temperature curing with an adjustable pot life. At a 1:1 weight ratio, the mixed viscosity stays at 600±200 cP. Operators have up to 4 hours of working time, enabling precise placement before curing begins. At 22°C, full cure completes in 24 hours.
The cured gel shows excellent transparency with ≥93% light transmission and long-term resistance to yellowing. Hardness is 25±5 Shore A00, providing gentle contact with delicate components. Volume resistivity is measured above 1.0×10¹⁴ Ω·cm, suitable for applications where insulation is needed.
Because the addition-cure mechanism produces no byproducts, the material can cure in deep sections without void formation. Volatiles remain low, and no solvents are used. The gel also resists moisture ingress and supports aging resistance under standard operating conditions.
Application involves cleaning and drying all substrates, mixing A and B thoroughly, and optionally degassing before dispensing. Heating the assembly speeds up the process and may enhance adhesion to certain surfaces. Keep the product away from contaminants containing N, P, S, Sn, Pb, Hg, or As. Unused product must be stored in original sealed containers in a cool, dry location. Shelf life is 6 months. The gel is shipped as a non-hazardous chemical.