Composition, foamed silicone elastomer formed therefrom, and methods of formation

• Main Authors: Brune, Douglas A, Su, Kai, Fisher, Mark D, Henning, Jody J, Wendt, Benjamin L, Sonnenschein, Mark F, Cramton, Jarred, Broderick, Adam H
• Format: Patent
• Language: English
• Published: 24.05.2022
• Subjects: AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F,C08G; CHEMISTRY; COMPOSITIONS BASED THEREON; GENERAL PROCESSES OF COMPOUNDING; MACROMOLECULAR COMPOUNDS OBTAINED OTHERWISE THAN BY REACTIONSONLY INVOLVING UNSATURATED CARBON-TO-CARBON BONDS; METALLURGY; ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; WORKING-UP

A composition for forming a foamed silicone elastomer is disclosed. The composition comprises: A) an organopolysiloxane having at least two silicon-bonded ethylenically unsaturated groups per molecule; B) an organohydrogensiloxane having at least two silicon-bonded hydrogen atoms per molecule; C) a hydrosilylation catalyst; D) a chemical blowing agent; and E) a physical blowing agent. The hydrosilylation catalyst C) is present in a catalytically effective amount. The chemical blowing agent D) has at least one hydroxyl (OH) group, and is present in an amount to provide a OH content >0 and <500 parts per million (ppm). The physical blowing agent E) undergoes a phase change from a liquid to a gaseous state during exposure to atmospheric pressure and a temperature ≥0° C. The blowing agents D) and E) are different from one another. A foamed silicone elastomer, and methods of forming the composition and foamed silicone elastomer are also disclosed.