Cure Of Silicone Rubber Coatings With Organic Peroxides And Ultraviolet Radiation
Original Publication Date: 1979-Sep-01
Included in the Prior Art Database: 2005-Feb-20
Clear smooth coatings of vulcanized silicone rubber have been success prepared by coating a substrate with silicone gum containing an organic fully peroxide and irradiating with ultraviolet light. The coatings were deposited from a solvent solution to obtain the desired dry film thickness. After solvent evaporation from the coating, a free radical crosslinking reaction was initiated by ultraviolet light. The process used a dialkyl or diaralkyl peroxide of low volatility which is soluble in the silicone and reacts primarily with pendant vinyl groups, thus producing a controlled cross-linked rubber. A nitrogen atmosphere was used to prevent oxygen inhibition of the peroxide. A post cure at 250 (degrees) C in air gave additional hydrothermal stability.