Loctite 596 Superflex RTV High Temperature Silicone Sealant Red 80ml

Loctite 596 Superflex (Henkel data sheet name: Loctite SI 596 Red) is a one-component, red, thixotropic acetoxy silicone. It is a moisture-curing RTV sealant and adhesive.

Henkel lists it for gasketing and sealing in plant maintenance and original equipment manufacturers, and as a sealant and adhesive for industrial furnaces, ovens, boilers, exhaust stacks, high temperature ducting and heating elements in electrical appliances. It is typically used in applications up to 315 °C.

Where this product is used

• Industrial furnaces, ovens and boilers
• Exhaust stacks and high temperature ducting
• Heating elements in electrical appliances
• Automotive valve covers, rocker covers and oil pans
• Water pumps, end seals, intake manifolds and rear axle housings

Features

• One component, no mixing; acetoxy RTV silicone
• Red, homogeneous, thixotropic paste
• Typically used in applications up to 315 °C
• Tack free in about 1 hour and fully cured in about 24 hours, depending on temperature, humidity and gap
• Peel strength of 1.73 N/mm or more on aluminium and steel (180 degree, 14 days at 25 °C)
• Formulated to meet low silicone volatiles requirements for 315 °C automotive flange sealants
• Heat-ageing data at 204 °C, 260 °C and 316 °C in the Henkel data sheet

Key specifications

Available sizes

Selecting the right option

For oxime silicones see Loctite 587 Blue Maxx Silicone Flange Sealant 300ml (blue) and Loctite 598 Black RTV Silicone Gasket Maker 95g (black), and for a copper-coloured, non-corrosive silicone see Loctite 5920 Copper Maxx Silicone 85g. Compare the temperature statements on each data sheet before choosing.

Using it

Tack free in about 1 hour and fully cured in about 24 hours; both vary with temperature, humidity and gap.

Heat-ageing results, tested at 22 °C: after 8 weeks at 204 °C, Shore A 22 and 500% elongation; after 7 weeks at 260 °C, Shore A 17, 210% elongation and tensile strength 0.3 N/mm²; after 3 weeks at 316 °C, Shore A 82 and 25% elongation. Check these against your operating temperature and service life.

Hardness, elongation and tensile strength on the data sheet are measured after 7 days at 25 °C and 50% RH. Peel strength is measured after 14 days at 25 °C.

Storage and handling

Store unopened in a dry location, optimally between 8 °C and 21 °C. Storage below 8 °C or above 28 °C can adversely affect the properties of the product. Henkel does not state a shelf life.

Limits and safety

Not recommended for gasketing carburettors or fuel control devices in constant contact with hydrocarbon fuels, where it swells and loses properties. Not for pure oxygen or oxygen-rich systems, or as a sealant for chlorine or other strong oxidisers. Henkel states no minimum service temperature.

Frequently asked questions

What temperature can Loctite 596 handle?

The data sheet says it is typically used in applications up to 315 °C. Heat-ageing data is given at 204 °C, 260 °C and 316 °C.

How fast does Loctite 596 cure?

Tack free in about 1 hour and fully cured in about 24 hours, depending on temperature, humidity and gap.

What should not be sealed with Loctite 596?

Carburettors or fuel control devices in constant contact with hydrocarbon fuels, pure oxygen or oxygen-rich systems, and chlorine or other strong oxidisers.

Does Loctite 596 stay flexible after long heat exposure?

Not at the top of the range. After 3 weeks at 316 °C the data sheet shows Shore A 82 and 25% elongation, against Shore A 22 and 500% elongation after 8 weeks at 204 °C.

What is the peel strength of Loctite 596?

At least 1.73 N/mm on aluminium and steel, measured at 180 degrees after 14 days at 25 °C.

Does Loctite 596 have approvals?

The current Henkel data sheet lists no approvals; contact AIMS if you need a certificate for a specific application.

Related products

See also: Loctite 587 Blue Maxx Silicone Flange Sealant 300ml, Loctite 598 Black RTV Silicone Gasket Maker 95g, Loctite 5920 Copper Maxx Silicone 85g, Loctite SI 5699 Grey RTV Silicone Gasket Maker, Loctite SI 5900 Flange Sealant 300ml.