Silicone rubber is a versatile elastomer that can be classified by curing method, physical form, chemical structure, and special functions.

1. By Curing Method

RTV Silicone Rubber (Room Temperature Vulcanizing)

• Cures at room temperature without heating.

• RTV-1: One-component, commonly used for sealants and glass bonding.

• RTV-2: Two-component, used for mold making, casting, and electronic potting.

HTV Silicone Rubber (High Temperature Vulcanizing)

• Requires curing at 150–200°C.

• Offers high strength and excellent durability.

• Used in automotive seals, insulators, wires, and industrial components.

2. By Physical Form

HCR (High Consistency Rubber)

• Solid silicone rubber.

• High strength and durability.

• Suitable for extrusion and compression molding.

LSR (Liquid Silicone Rubber)

• Two-component liquid system.

• High purity, transparency, and fast curing.

• Widely used in medical devices, baby products, and wearables.

3. By Chemical Structure

MQ (Methyl Silicone Rubber)

• Basic silicone rubber with good heat and electrical resistance.

MVQ (Methyl Vinyl Silicone Rubber)

• Most widely used type.

• Excellent balance of performance and cost.

• Good UV, ozone, and aging resistance.

PVMQ (Phenyl Silicone Rubber)

• Superior low-temperature performance.

• Some grades remain flexible below -100°C.

• Common in aerospace and extreme environments.

4. By Special Function

Medical Grade Silicone Rubber

• Biocompatible and sterilization resistant.

• Used in implants, tubing, and medical devices.

Food Grade Silicone Rubber

• Non-toxic and odorless.

• Meets FDA and food-contact standards.

Fluorosilicone Rubber (FVMQ)

• Excellent resistance to fuels, oils, and solvents.

• Used in automotive and aerospace systems.

Conductive Silicone Rubber

• Provides electrical conductivity and EMI shielding.

Thermally Conductive Silicone Rubber (TCSR)

• Enhanced heat dissipation for electronics and batteries.

Sponge/Foam Silicone Rubber

• Lightweight with cushioning and sealing properties.

• Used for insulation, sealing, and vibration damping.

Summary

The most common silicone rubber types are RTV, HTV, HCR, LSR, MVQ, PVMQ, medical-grade, food-grade, fluorosilicone, conductive, and thermally conductive silicone rubber. Each type is designed for specific applications ranging from consumer products and electronics to automotive, medical, and aerospace industries.