LOCTITE SI 207 Neutral Cure Silicone Sealant is a one-component RTV silicone developed for reliable sealing and flexible bonding across polycarbonate, general plastics, mirrors, nonferrous metals, concrete, and ceramics. Its neutral oxime cure system is non-corrosive, making it a practical choice for assemblies where conventional acetic-cure silicone may be unsuitable. The thixotropic paste stays in place after dispensing, supporting controlled application on vertical joints, component edges, housings, panels, and irregular sealing areas.

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LOCTITE SI 207 Neutral Cure Silicone Sealant for Versatile Sealing

Industrial and construction assemblies often combine materials with different expansion rates. Rigid adhesives may crack or lose adhesion when these substrates move during temperature changes. LOCTITE SI 207 cures into a soft, flexible silicone rubber that can accommodate movement while maintaining a dependable environmental barrier.

The ready-to-use formula requires no weighing or mixing. Once exposed to atmospheric moisture, curing begins immediately at room temperature. This convenient process supports manual dispensing, automated production, maintenance, repair, and general-purpose sealing without requiring heating equipment or a separate curing agent.

The product offers a service-temperature range from approximately -54°C to 204°C, making it suitable for assemblies exposed to cold conditions, operating heat, or repeated thermal cycling. Its non-corrosive behavior is especially valuable when working around mirrors and nonferrous metals, while its compatibility with polycarbonate and other plastics expands its use in transparent covers, protective housings, panels, and display-related assemblies.

LOCTITE SI 207 Neutral Cure Silicone Sealant Performance Benefits

LOCTITE SI 207 Neutral Cure Silicone Sealant develops an initial fixture time of approximately 15 minutes at 25°C and 60% relative humidity. The manufacturer lists complete cure at approximately 24 hours under stated conditions, although thick sections, enclosed joints, low humidity, and cooler temperatures may extend the curing process. For assemblies exposed to heavy service loads, allowing additional curing time is recommended.

After curing, the silicone provides approximately 400% elongation at break and a Shore A hardness of around 18. This combination creates a soft, elastic seal capable of absorbing vibration, joint movement, impact, and thermal expansion. Typical tensile strength is approximately 1.0 N/mm², while peel strength is around 4.0 N/mm under the stated test method.

The cured material offers excellent environmental resistance and water-vapor resistance, supporting applications that require protection from humidity and normal atmospheric exposure. Its electrical properties, including high volume and surface resistivity, also make it useful for selected electrical sealing and insulating applications where a flexible, non-corrosive silicone barrier is required.

Typical uses include sealing polycarbonate covers, attaching or sealing mirrors, filling joints around ceramic parts, sealing concrete interfaces, protecting nonferrous metal assemblies, and creating flexible barriers around plastic housings. Actual adhesion depends on substrate formulation, cleanliness, surface treatment, joint design, and operating conditions, so testing should be completed before full production.

How to Apply LOCTITE SI 207 Neutral Cure Silicone Sealant

Clean all surfaces before application and remove grease, oil, dust, moisture, release agents, corrosion, and loose contamination. Cut the nozzle to the required bead size and dispense a continuous, controlled layer onto the prepared surface. Assemble the components within a few minutes because moisture curing starts as soon as the sealant is exposed to air.

Tool the bead before a surface skin forms and keep the joint undisturbed during the initial curing period. Ensure that atmospheric moisture can reach the material, as very deep or fully enclosed sections cure more slowly. Excess uncured sealant may be removed using a suitable non-polar solvent, subject to substrate compatibility and workplace safety requirements.

Do not use the product in pure oxygen, oxygen-rich systems, chlorine service, or contact with strong oxidizing materials. Store unopened containers in a dry location, ideally between 8°C and 21°C.

LOCTITE SI 207 Neutral Cure Silicone Sealant is a dependable purchasing option for manufacturers, contractors, maintenance teams, and distributors seeking flexible adhesion, broad material compatibility, non-corrosive curing, and reliable performance across demanding temperature and environmental conditions.

industrial silicone adhesives and sealants

LOCTITE SI 207 Neutral Cure Silicone Sealant