RTV silicone

RTV Silicone (Room-Temperature-Vulcanization silicone) is a type of silicone rubber made from a two-component system (base plus curative; A+B) available in a hardness range of very soft to medium--usually from 15 Shore A to 40 Shore. RTV silicones can be cured with a catalyst consisting of either platinum or a tin compound such as dibutyltin dilaurate. Applications include low-temperature overmolding, making molds for reproducing, and lens applications for some optically clear grades.

To produce the material, the silicone rubber is mixed with the curing agent or vulcanizing agent. Usually the mixing ratio is a few percent. In order for the RTV silicone to reproduce the surface texture, attention is paid to the cleanliness of the original. Vacuum de-airing removes entrained air bubbles from the mixed silicone and catalyst to ensure optimal tensile strength, which affects reproduction times. In casting and mold-making, RTV silicone rubber reproduces fine details and is suitable for a variety of industrial and art-related applications including prototypes, furniture, sculpture, and architectural elements. RTV silicone rubber can be used to cast materials including wax, gypsum, low melt alloys/metals and urethane, epoxy or polyester resins (without using a release agent). A more recent innovation is the ability to 3D Print RTV silicones. RTV silicones' industrial applications include aviation, aerospace, consumer electronics, and microelectronics. Some aviation and aerospace product applications are cockpit instruments, engine electronics potting, and engine gasketing. RTV silicones are used for their ability to withstand mechanical and thermal stress.

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