Firm-durometer tin-cure RTV-2 potting and encapsulation silicone

General Information

GI-300 series RTV silicone rubbers are two-component, tin-catalyzed systems that cure at room temperature. They are versatile products that are excellent for electrical potting and encapsulation. They can also be used for prototype or production molds to cast polyester, polyurethane or epoxy parts where flexing is not required. They are low viscosity compounds with a variety of hardnesses. The GI-300 series rubbers are not sensitive to inhibition, meaning they will cure at room temperature over virtually any surface. The speed at which the rubbers harden can be accelerated with special activators. The GI-300 series rubbers are especially useful in those applications where outstanding heat resistance and chemical resistance are required.

Typical Properties

Uncatalyzed Compound

Color

Base:BeigeActivator:n.a.

Viscosity

Base:30,000–40,000cpsActivator:n.a.cps

Mixing Ratio

By weight:100:10By volume:100:14.8

Mixed Viscosity

15,000–25,000cps

Working Time

1.0–2.0hours

Cure Time

16–18hours

Shelf Life

6months

Vulcanized (Cured) Properties

Measured at 7 days, 70°F / 50% relative humidity

Shore A Hardness

One day:577 days:60

±4 durometer

Tear Resistance

25ppiASTM D624

Tensile Strength

450psiASTM D412

Elongation

100%ASTM D412

Service Temperature

-60 to 425°F

Shrinkage

0.15%

Specific Gravity

1.45

Coverage

19.1in³ / lb

Arc resistance

125 seconds

Volume resistivity

1 x 10^13 ohms/cm

Dielectric strength

575 volts/mil

Thermal conductivity

7 x 10^-4 cal/cm2/degC/sec/cm

Dissipation factor (@ 100 Hz)

0.03

Dielectric constant (@ 100 Hz)

3.7

Coefficient of thermal expansion

10 x 10^-4 cm/cm/degC