Abstract: A dual-cure silicone composition is provided that is useful to make an encapsulating/potting compound. The dual-cure silicone exhibits both UV- and moisture-initiated curing mechanisms, with the UV-initiated curing mechanism providing very rapid curing compared to conventional dual-cure silicones. The dual-cure silicone is an elastomeric material on curing. In a preferred embodiment, the dual-cure silicone composition is made from a mixture of a first polysiloxane component having terminal mercapto and alkoxy functionality, and a second polysiloxane component having terminal vinyl and alkoxy functionality. Methods of making the first and second polysiloxane components also are disclosed.

Abstract: A dual-cure silicone compound is provided that is useful as an encapsulating/potting compound. The dual-cure silicone exhibits both UV- and moisture-initiated curing mechanisms, with the UV-initiated curing mechanism providing very rapid curing compared to conventional dual-cure silicones. The dual-cure silicone is an elastomeric material on curing. In a preferred embodiment, the dual-cure silicone is made from a mixture of a first polysiloxane component having terminal mercapto and alkoxy functionality, and a second polysiloxane component having terminal vinyl and alkoxy functionality. Methods of making the first and second polysiloxane components also are disclosed.

Abstract: A polyurethane sealant composition is made from a polyurethane prepolymer having blocked isocyanate groups. A bicyclic amidine catalyst is utilized in association with an amine curing agent having at least two primary amine groups to achieve a relatively fast cure time. In the first embodiment, the catalyst is 1,8-diazobicyclo (5:4:0) undecene-7 (DBU), whereas in a second embodiment the catalyst is 1,5-diazobicyclo (4:3:0) non-5-ene (DBN).

Abstract: A polyurethane sealant composition is made from a polyurethane prepolymer having blocked isocyanate groups. A 1,8-diaza bicyclo(5:4:0)undecene-7 (DBU) catalyst or a derivative thereof is utilized in association with an amine curing agent having at least two primary amine groups to achieve a relatively fast cure time. The catalyst is a true catalyst in that it merely aids in unblocking the isocyanate groups whereby the curing agent can react therewith.