Yes, SILICONES is a Scrabble word!

Letter values in Scrabble US: S 1, I 1, L 1, I 1, C 3, O 1, N 1, E 1, S 1.

Is it a valid word?

SILICONES is a valid word in the official Scrabble dictionary (US), the UK Scrabble Dictionary and Words with Friends (ENABLE).

any of a large class of siloxanes that are unusually stable over a wide range of temperatures; used in lubricants and adhesives and coatings and synthetic rubber and electrical insulation

Also: silicone polymer.