Moldable Silicone for EMI Gaskets

Specialty Silicone Products (SSP) makes moldable silicone and  fluorosilicone compounds gaskets that combine environmental sealing with shielding against electromagnetic interference (EMI).

Why Moldable Silicone Is Essential for EMI Gaskets

The role of conductive elastomers in EMI shielding

Electromagnetic interference (EMI) is a growing challenge across aerospace, defense, communications, and high‑reliability electronics. As devices become smaller, faster, and more densely packaged, the need for reliable EMI shielding materials has never been greater. Conductive elastomers—especially moldable silicone—play a critical role in blocking unwanted interference while maintaining environmental sealing. These materials combine electrical conductivity with the flexibility and durability required for long‑term gasket performance.

Balancing electrical performance with environmental sealing

EMI gaskets must do more than conduct electricity. They also need to withstand temperature extremes, vibration, humidity, and mechanical compression. Moldable silicone provides an ideal balance of electrical and mechanical properties, making it suitable for mission‑critical applications where failure is not an option.

Why silicone is preferred for mission‑critical electronics

Silicone’s inherent stability, wide temperature range, and resistance to UV and ozone make it a top choice for EMI gaskets. When filled with conductive particles, silicone becomes a highly effective EMI shielding material that can be molded into complex shapes without sacrificing performance.

SSP’s Expertise in Conductive Silicone Formulation

In‑house material development for EMI/RFI applications

Specialty Silicone Products (SSP) has built a reputation as one of the industry’s most capable suppliers of moldable silicone compounds engineered specifically for EMI gaskets. SSP formulates these materials in‑house, giving engineers access to compounds optimized for shielding effectiveness, compression set resistance, environmental durability, and chemical resistance.

Tailoring durometer, viscosity, and cure profiles for molding

Because SSP controls the formulation process, the company can tailor durometer, filler loading, viscosity, and cure characteristics to support compression, transfer, and injection molding. This ensures molders can achieve tight tolerances and consistent electrical performance.

Ensuring consistency and repeatability across production batches

SSP’s ISO‑certified manufacturing processes ensure batch‑to‑batch consistency—critical for aerospace, defense, and high‑reliability electronics. Every compound is engineered for predictable flow, cure, and part‑to‑part repeatability.

Conductive Filler Systems Engineered for Shielding Performance

Nickel‑graphite for cost‑effective commercial EMI gaskets

Nickel‑graphite is widely used in commercial and industrial electronics. It offers good shielding performance at a lower cost than precious‑metal fillers.

Silver‑aluminum for MIL‑DTL‑83528 compliance

Silver-aluminum fillers provide excellent conductivity and strong galvanic compatibility with aluminum housings. SSP supplies multiple silver‑aluminum compounds that meet MIL‑DTL‑83528 Type B and Type D requirements.

Silver‑copper for maximum conductivity

Silver‑copper compounds deliver extremely high shielding effectiveness and are used in applications where maximum conductivity is required. SSP offers QPL‑listed Type A and Type K materials.

Silver‑nickel for corrosion‑resistant aerospace applications

Silver‑nickel fillers provide excellent corrosion resistance and long‑term stability, making them ideal for mission‑critical aerospace and defense systems.

Nickel‑aluminum for harsh environments and galvanic compatibility

Nickel‑aluminum compounds offer a balance of shielding performance and environmental durability, especially in marine and outdoor environments.

Moldable Silicone Compounds Designed for Manufacturing Efficiency

Ready‑to‑mold compounds for compression, transfer, and injection molding

SSP supplies EMI silicones in ready‑to‑mold compound form, engineered for consistent flow and cure. These materials support compression molding of flat gaskets, transfer molding of connector seals, and injection molding for high‑volume production.

Flow characteristics optimized for complex geometries

SSP’s compounds are formulated to fill intricate mold cavities without voids or inconsistencies, enabling the production of complex EMI gasket geometries.

Achieving tight tolerances and consistent electrical performance

Predictable cure kinetics and controlled filler dispersion allow molders to achieve tight dimensional tolerances and reliable shielding effectiveness across production runs.

Meeting MIL‑DTL‑83528 Requirements

QPL‑listed materials for defense and aerospace programs

SSP is one of the few U.S. manufacturers with QPL‑listed conductive elastomers. These materials are trusted by defense contractors and aerospace OEMs worldwide.

Types A, B, D, and K conductive silicone compounds

SSP supplies moldable silicones that meet or exceed MIL‑DTL‑83528 requirements for Types A, B, D, and K, covering a wide range of conductivity and hardness profiles.

Shielding effectiveness and volume resistivity standards

These materials are engineered for high shielding effectiveness, low volume resistivity, and long‑term reliability in harsh environments.

Custom Formulations for Specialized EMI Gasket Applications

Modifying filler loading, durometer, and cure speed

SSP can customize durometer, viscosity, cure speed, and filler loading to meet application‑specific requirements.

Designing materials for unique environmental or chemical exposures

Fluorosilicone versions are available for applications requiring resistance to fuels, oils, and solvents—common in aerospace and defense.

Supporting application‑specific electrical and mechanical requirements

Custom formulations allow engineers to optimize EMI gaskets for unique enclosure designs, compression requirements, or environmental conditions.

Supporting Prototype and Production‑Scale Molding

Material options for low‑volume development and high‑volume production

SSP supplies moldable EMI silicones in quantities suitable for prototyping, pilot runs, and full‑scale production.

Common molded EMI gasket types and geometries

Molders use SSP compounds to produce connector gaskets, O‑rings, flat gaskets, overmolded components, and complex multi‑cavity parts.

Ensuring part‑to‑part consistency across molding cycles

SSP’s compounds are engineered for predictable flow and cure, ensuring consistent part quality across production runs.

Made in the USA with Full Traceability

ISO‑certified manufacturing in Ballston Spa, NY

All SSP EMI silicone compounds are manufactured in the United States under an ISO 9001:2015 certified quality system.

Certificates of Analysis and batch documentation

Customers receive full traceability and documentation with every order—essential for regulated industries.

Quality assurance for high‑reliability electronics

SSP’s rigorous quality controls ensure that every batch meets the electrical, mechanical, and environmental requirements of high‑reliability applications.

Why Engineers Choose SSP for Moldable EMI Silicone

Proven performance in aerospace, defense, and electronics

SSP’s materials are trusted by engineers designing mission‑critical systems where failure is not an option.

Deep materials expertise and responsive technical support

SSP’s team helps engineers select the right material, optimize molding processes, and meet compliance requirements.

Ability to scale from prototype to production seamlessly

From early‑stage development to full‑scale manufacturing, SSP provides the materials and support needed to bring EMI gasket designs to life.

FAQ: Moldable Silicone for EMI Gaskets

What makes moldable silicone a good choice for EMI gaskets?

Moldable silicone combines electrical conductivity with excellent environmental sealing, making it ideal for EMI gaskets used in aerospace, defense, and high‑reliability electronics. When filled with conductive particles, silicone provides both shielding effectiveness and long‑term durability.

What types of conductive fillers are available in SSP’s moldable EMI silicones?

SSP formulates moldable silicones using several filler systems, including nickel‑graphite, silver‑aluminum, silver‑copper, silver‑nickel, and nickel‑aluminum. Each filler type offers different levels of conductivity, corrosion resistance, and galvanic compatibility.

Can SSP’s moldable silicones meet MIL‑DTL‑83528 requirements?

Yes. SSP manufactures multiple QPL‑listed conductive elastomers that meet MIL‑DTL‑83528 Types A, B, D, and K. These materials are widely used in defense and aerospace applications requiring proven EMI shielding performance.

What molding processes are compatible with SSP’s EMI silicone compounds?

SSP’s moldable EMI silicones are engineered for compression, transfer, and injection molding. They offer predictable flow and cure behavior, allowing molders to produce complex gasket geometries with tight tolerances.

How does SSP ensure consistency in EMI silicone compounds?

All SSP materials are manufactured in the United States under an ISO 9001:2015 certified quality system. Each batch is tested for electrical, mechanical, and physical properties, and customers receive full traceability and Certificates of Analysis.

Can SSP customize EMI silicone compounds for unique applications?

Yes. SSP can modify durometer, viscosity, cure speed, filler loading, and other properties to meet application‑specific requirements. Custom formulations are available for unique environmental, chemical, or electrical performance needs.

What types of EMI gaskets can be molded from SSP’s silicone compounds?

Molders use SSP’s compounds to produce connector gaskets, O‑rings, flat gaskets, overmolded components, and complex multi‑cavity parts. The materials are suitable for both prototype and production‑scale molding.

What is the difference between silicone and fluorosilicone EMI materials?

Silicone offers excellent temperature and environmental resistance, while fluorosilicone adds superior resistance to fuels, oils, and solvents. Fluorosilicone is often chosen for aerospace and defense applications with harsh chemical exposure.