5 g of hydroxy terminated PDMS was weighed in a beaker and mixed with 600 uL of 3-(Trimethosysilyl)propl methacrylate. Tetrahydrofuran was added to lower the viscosity and allow these components to mix. Then 60 uL of the catalyst, dibutyltin dilaurate, was added. The mixture was stirred at 60 ℃ for 3 hours until the Tetrahydrofuran was mostly evaporated. Separately, 50 mg of the photoinitiator, irgacure-2949, was dissolved in 50 mL of tetrahydrofuran and then added to the PDMS. This was stirred without heating for one hour or until the tetrahydrofuran was mostly evaporated again. Fumed silica was added as a rheological modifier. About 750 mg of fumed silica provided the desired viscosity and flow characteristics. This protocol was developed based on a previously published photocurable PDMS recipe.