RTV Silicone Sealant Guide

RTV silicone sealants are one-component or multi-component silicone materials that cure at room temperature to form a flexible, durable rubber seal. RTV stands for Room Temperature Vulcanizing, referring to the curing process that allows the material to transition from a paste or liquid into an elastomeric silicone rubber without requiring elevated-temperature processing.

RTV silicone sealants are used throughout aircraft maintenance, aerospace manufacturing, electronics, equipment assembly, and industrial applications. Depending on the formulation, RTV products can provide excellent flexibility, temperature resistance, moisture resistance, electrical insulation, adhesion, and resistance to weathering and environmental exposure.

Business Aircraft Consumables (BAC) supplies RTV silicone sealants from manufacturers including DOWSIL™ and Momentive. Our selection includes general-purpose, high-temperature, high-strength, electrically insulating, and specialized RTV formulations for demanding maintenance and MRO applications.

What Does RTV Mean?

RTV means Room Temperature Vulcanizing. Unlike some sealants and adhesives that require heat to cure, RTV silicone sealants cure through a chemical reaction after exposure to moisture or other curing agents. Many one-component RTV products are supplied ready to use and cure when exposed to moisture in the surrounding air.

One-component RTV silicone products are particularly convenient for maintenance applications because they do not require mixing immediately before application. Depending on the formulation, they can be applied to horizontal, vertical, or overhead surfaces and cure to a flexible silicone rubber.

For example, DOWSIL™ 732 is a one-component acetoxy-cure silicone adhesive/sealant that cures at room temperature when exposed to moisture in the air. The product is designed to form a tough, flexible rubber and is available in several colors. It also complies with MIL-A-46106.

Common Applications for RTV Silicone Sealants

RTV silicone sealants are used in a wide range of aerospace, aircraft maintenance, electrical, and industrial applications. The correct product depends on the temperature, environmental exposure, substrates, required flexibility, and applicable specifications.

• Aircraft component sealing
• Electrical insulation
• Electronic component protection
• Formed-in-place gaskets
• Equipment and housing sealing
• Wire and cable sealing
• Avionics applications
• Engine and high-temperature applications
• Panel and enclosure sealing
• Moisture and environmental protection
• Bonding and assembly applications

Types of RTV Silicone Sealants

Not all RTV silicone sealants are interchangeable. Different formulations are designed for different temperature ranges, substrates, cure characteristics, strength requirements, and environmental conditions.

RTV Silicone Sealants for Aerospace and Aircraft Maintenance

Silicone sealants are particularly useful in aerospace applications because cured silicone rubber remains flexible over a wide range of temperatures and can provide resistance to moisture, weathering, vibration, and environmental exposure.

Depending on the formulation, RTV silicone may be used for aircraft component sealing, electrical insulation, avionics applications, equipment housings, formed-in-place gaskets, and specialized high-temperature applications. The specific sealant must always be selected according to the applicable aircraft maintenance documentation, component requirements, and manufacturer specifications.

BAC's silicone selection includes products designed for different aerospace and industrial requirements. For example, DOWSIL™ RTV730 is a fluorosilicone sealant designed for applications exposed to fuels, oils, and solvents, while DOWSIL™ RTV736 is formulated for high-temperature applications and can operate continuously at temperatures up to 500°F, with intermittent exposure up to 600°F.

RTV Silicone vs. Other Aircraft Sealants

RTV silicone sealants should not be treated as a universal replacement for other aircraft sealant chemistries. Aerospace sealants are formulated for specific environments and applications, and the correct material depends on what the sealant must resist and how it must perform after curing.

Silicone RTV is often selected when flexibility, temperature resistance, weatherability, electrical insulation, or general sealing performance is important. Other aerospace sealants may be preferred where resistance to aviation fuel, hydraulic fluid, or other specific chemicals is the primary requirement.

Always verify the applicable aircraft or component maintenance manual and the sealant manufacturer's technical data before selecting a replacement or alternate sealant.

Examples of RTV Silicone Sealants Available from BAC

How to Choose an RTV Silicone Sealant

Selecting the correct RTV silicone sealant requires more than choosing a product based on color or temperature rating. Consider the complete application before selecting a sealant.

1. Identify the application. Determine whether the material will be used for sealing, bonding, gasketing, electrical insulation, encapsulation, or another purpose.
2. Check the temperature range. Verify both the continuous operating temperature and any intermittent or peak temperature exposure.
3. Consider chemical exposure. Determine whether the cured sealant will contact fuel, oil, hydraulic fluid, solvents, cleaning chemicals, or other substances.
4. Identify the substrates. Confirm that the RTV formulation provides suitable adhesion to the materials being joined or sealed.
5. Determine the required cure characteristics. Consider cure mechanism, cure time, application thickness, and whether a one-component or multi-component system is appropriate.
6. Check the applicable specification. Verify whether the application requires compliance with a military, aerospace, OEM, or other industry specification.
7. Review the manufacturer's technical data. Always confirm the product's latest technical data sheet, application instructions, compatibility, and limitations before use.

RTV Silicone Sealant Cure Time

RTV silicone cure time varies by formulation, temperature, humidity, application thickness, and other conditions. Many one-component RTV products cure through exposure to atmospheric moisture, meaning the material generally cures from the outside inward.

For example, Momentive RTV102, RTV106, and RTV108 are one-component acetoxy silicone sealants that require approximately three days for full cure under the conditions specified by the manufacturer. Actual cure behavior can vary depending on the application and environment.

Always consult the manufacturer's technical data sheet for the specific product rather than assuming that all RTV silicone sealants have the same cure time.

RTV Silicone Sealant Temperature Resistance

Temperature resistance varies significantly between RTV formulations. General-purpose silicone sealants may be suitable for moderate temperatures, while specialized high-temperature RTV products are designed for substantially higher continuous or intermittent temperatures.

For example, DOWSIL RTV736 is formulated for continuous service from approximately -85°F to 500°F, with intermittent exposure up to 600°F. Other RTV products have different operating ranges, so the temperature rating should always be verified for the specific product being used.

RTV Silicone Sealant FAQs

What does RTV stand for?

RTV stands for Room Temperature Vulcanizing. RTV silicone sealants cure at or near room temperature to form a flexible silicone rubber.

What is RTV silicone sealant used for?

RTV silicone sealants are used for sealing, bonding, gasketing, electrical insulation, component protection, and other applications. Aerospace uses can include aircraft component sealing, avionics, electrical assemblies, equipment housings, and specialized high-temperature applications.

Are all RTV silicone sealants the same?

No. RTV silicone formulations differ in cure chemistry, temperature resistance, chemical resistance, strength, viscosity, adhesion, flexibility, and applicable specifications. Always select an RTV product based on the requirements of the specific application.

What is the difference between RTV silicone and regular silicone sealant?

RTV describes a silicone material that cures at room temperature. The term silicone sealant is broader and can describe products with different curing systems and intended applications. Many RTV products are supplied as ready-to-use silicone sealants.

Is RTV silicone suitable for aircraft?

Certain RTV silicone sealants are used in aerospace and aircraft applications, but suitability depends on the specific product, application, materials, environmental exposure, and applicable aircraft or component documentation. Do not substitute one sealant for another without verifying the applicable requirements.

What RTV silicone meets MIL-A-46106?

BAC carries several RTV silicone products that comply with or are identified with MIL-A-46106 requirements, including DOWSIL RTV732 and RTV736 and Momentive RTV102, RTV106, and RTV108. Always verify the current manufacturer's technical documentation and the specific revision or type required by your application.

Shop RTV Silicone Sealants at BAC

BAC stocks RTV silicone sealants for aircraft maintenance, aerospace, MRO, electrical, and industrial applications. Browse our selection of RTV silicone sealants from DOWSIL and Momentive, including general-purpose, high-temperature, high-strength, and specialized formulations.

If you need help identifying the correct RTV silicone sealant for an aircraft maintenance application, compare the required specification, temperature range, chemical exposure, substrate, and application requirements with the manufacturer's technical data.