The comparisons of Liquid silicone and Polyurethane resin for electronic potting
Features and Properties Silicone rubber Polyurethane resin
Modification ability Better modification ability and good electrical insulation ability by adding different additives Could be modified its own thermal conductivity based on different products potting
Resistance for high and low temp Excellent resistance for temp, do not crack and stay good elasticity under temp from -60℃~200℃; better for working under harsh environment Easy crack especially under high and low changing temp; thereof, effect the moisture resistance
Hardness and flexibility Lower hardness, better flexibility High hardness, very stiff, less flexibility, therefore, less anti-shock ability
Heat and corrosive substance release Do not release heat and corrosive substance during curing, more friendly and protective for  Electronic Components Will release more or less heat during curing
UV-proof and anti-aging Better UV-proof and anti-aging  
Adhesive ability Slightly less than Polyurethane resin under normal condition, but could be largely increased with premier Better than silicone rubber
Applications Excellent materials for electronic parts potting, especially for precision components potting and protection Excellent and economic materials for electronic parts potting