Optical article and method of forming

A method of forming an optical article, comprising:

• applying a silicone composition to a surface, wherein the silicone composition is a solid and has a glass transition temperature greater than room temperature;
• and
• heating the silicone composition to a temperature at or above the glass transition temperature such that the silicone composition flows;
• wherein:
• the silicone composition forms a light transmitting sheet upon cooling following the heating;
• and
• the silicone composition comprises an organosiloxane block copolymer having a weight average molecular weight of at least 20,000 g/mole and comprises:
• 40 to 90 mole percent disiloxy units of the formula [R12SiO2/2] arranged in linear blocks each having an average of from 10 to 400 disiloxy units [R12SiO2/2] per linear block;
• 10 to 60 mole percent trisiloxy units of the formula [R12SiO3/2] arranged in non-linear blocks each having a weight average molecular weight of at least 500 g/mole;
• and
• 0.5 to 25 mole percent silanol groups [≡SiOH];
• wherein R1 is independently a C1 to C30 hydrocarbyl and R2 is independently a C1 to C20 hydrocarbyl,
• wherein at least 30 weight percent of the non-linear blocks are crosslinked with another non-linear block and aggregated in nano-domains, and
• wherein each linear block is linked to at least one non-linear block.