"Silicone" is not one material — it is a family of elastomers engineered for very different jobs. Choosing the right type is the difference between a part that lasts and one that fails. This guide maps the main silicone types to the applications they serve.
Silicone Types at a Glance
| Type | What it is | Typical use |
|---|---|---|
| HTV (high-temperature vulcanizing / solid silicone) | Solid silicone rubber cured with heat; peroxide or platinum cure | Gaskets, seals, kitchenware, general molded parts |
| LSR (liquid silicone rubber) | Two-part platinum-cured liquid, injection molded | Medical, baby, high-volume precision parts, cleanroom molding |
| RTV (room-temperature vulcanizing) | Cures at room temperature; used for potting, sealing, molds | Adhesives, sealants, casting, prototyping molds |
| Food-grade silicone | Tested to FDA 21 CFR 177.2600 / LFGB | Kitchenware, bakeware, baby feeding, food contact |
| Medical-grade silicone | USP Class VI / ISO 10993 biocompatible, platinum-cured | Medical devices, fluid path, wearables, non-implant |
| Fluorosilicone (FVMQ) | Silicone with fuel and oil resistance | Automotive, aerospace, fuel-system seals |
| Conductive silicone | Carbon or metal-filled for EMI / RFI shielding | EMI gaskets, connector seals, static-dissipative keypads |
| Thermally conductive silicone | Alumina or boron-nitride filled for heat transfer | Thermal pads, gap fillers, EV and power electronics |
| Transparent / optical silicone | High light transmission, low haze | Transparent gaskets, light guides, optical overlays |
Choosing by Application
- Food and kitchen → food-grade HTV or LSR, certified to FDA / LFGB.
- Medical and baby → platinum-cured LSR or medical-grade HTV with ISO 10993 testing.
- Automotive under-hood and fuel → FVMQ fluorosilicone for oil/fuel resistance plus wide temperature swing.
- Electronics and EMI → conductive silicone for shielding, or thermally conductive silicone for heat transfer.
- Optical and display → transparent silicone for light transmission.
How CYES SILICONE Helps You Choose
We compound and mold across the silicone family — solid HTV, LSR, FVMQ fluorosilicone, and functional grades (conductive, thermally conductive, transparent) — in Shore A 20–80. Our engineers select the type, cure route and grade against your temperature, fluid, compliance and cost requirements, then verify the result per ASTM and ISO methods before release.
For a deeper view, see our silicone material selection guide, our elastomer comparison, and our specialty molding materials page covering FVMQ, PEEK, PA66-GF and functional silicone grades.