RTV 3145

DOWSIL™ 3145 RTV MIL-A-46146 Adhesive Sealant Clear is a clear, non-flowing, one-part polydimethylsiloxane adhesive sealant with high tensile strength and elongation. It cures at room temperature with atmospheric moisture, requires no mixing or ovens, and its cure can optionally be accelerated with mild heat. It is used for sealing openings in modules and housings, assembly of components on printed wiring boards and sealing in and around wires and electrical leads.

Specification

• MIL-A-46146 Group II Type I tested

Typical Properties

• Clear; extrusion rate 78.6 g/min; flow 0.092 in; non-volatile content 96.9%
• Tack-free time at 25 °C 63.8 min; specific gravity (cured) 1.10
• Tensile strength 864 psi; elongation 626%; tear strength (Die B) 223 ppi; hardness 45.6 Shore A
• Unprimed lap shear to aluminium 2.32 MPa
• Dielectric strength 485 V/mil; volume resistivity 4.4 x 10¹⁴ ohm·cm; dielectric constant (100 Hz) 2.83

Use

• Cures at room temperature at 30–80% relative humidity, from the exposed surface inward at about 6.35 mm per 7 days
• Mild heat below 60 °C may be used to accelerate cure; not for highly confined spaces or deep section cure
• Clean and degrease surfaces with a suitable solvent such as naphtha, mineral spirits or MEK