PPG P/S 870 MIL-PRF-81733 Type II Corrosion Inhibitive Sealant – Quart Kit

PPG P/S 870 is a premium two-component polysulfide corrosion inhibitive sealant meeting MIL-PRF-81733 Type II, Class 1, Grade A specification. Specifically engineered for aircraft fuel tanks, wet bays, and structural areas where both sealing performance and active corrosion inhibition are critical requirements, it provides a dual-function solution that simultaneously seals against fuel and moisture ingress while inhibiting corrosion of adjacent metal surfaces.

The active corrosion inhibitor system in P/S 870 releases inhibitor chemistry in the presence of moisture and corrosive agents, actively protecting aluminum alloy aircraft structures in and around the sealed joint from electrochemical corrosion attack. This self-protecting behavior extends the service life of the sealed assembly and reduces the frequency and extent of corrosion-related maintenance, delivering long-term lifecycle cost savings for aircraft operators.

Supplied as a convenient quart kit with pre-measured base and accelerator components, P/S 870 is ready to mix and apply following PPG’s mixing and application instructions. The quart kit provides sufficient material for moderate-scale sealing operations including fuel tank inspection panel resealing, wet bay maintenance, and structural corrosion protection sealing.

Technical Information

PPG P/S 870 is based on a polysulfide polymer system that provides the well-established fuel resistance, flexibility, and adhesion characteristics of aerospace polysulfide sealants, enhanced with an active corrosion inhibitor package. The two-component base and accelerator must be mixed in the specified ratio prior to application, initiating an oxidative crosslinking reaction that transforms the liquid sealant into a tough, chemically resistant elastomeric film as curing proceeds.

The corrosion inhibitor component is dispersed throughout the sealant matrix and is released gradually over the service life of the joint, providing sustained active corrosion protection to metal surfaces in contact with or adjacent to the sealant bead. This inhibitor release mechanism is particularly valuable in areas where water and contamination can accumulate at the sealant-metal interface, where conventional non-inhibited sealants provide only passive barrier protection.

P/S 870 cure rate can be adjusted to suit application requirements — the MIL-PRF-81733 Grade A classification specifies a defined cure rate appropriate for standard production and maintenance applications. The working life (pot life) after mixing must be observed to ensure the sealant remains workable throughout the application without premature gelling. Refer to PPG’s technical data sheet for mixing ratio, pot life, application parameters, and cure schedule at various temperatures.

Why Choose PPG P/S 870 Corrosion Inhibitive Sealant?

• ✅ MIL-PRF-81733 Type II Qualified — Military and commercial aerospace specification
• ✅ Active Corrosion Inhibition — Dual sealing and corrosion protection in one product
• ✅ Fuel Tank Approved — Resists continuous aviation fuel immersion
• ✅ Quart Kit Format — Pre-measured components, ready to mix and apply
• ✅ Long Service Life — Inhibitor release reduces corrosion maintenance frequency

Applications and Compatible Aircraft

PPG P/S 870 is used in aircraft integral fuel tanks, wet bay structural joints, inspection panel resealing, and corrosion-critical structural sealing on commercial, business, and military aircraft where MIL-PRF-81733 Type II corrosion inhibitive polysulfide sealant is specified.

Frequently Asked Questions

Q: What makes P/S 870 a ‘corrosion inhibitive’ sealant?
A: P/S 870 contains active corrosion inhibitors that are released over the service life of the sealant, actively protecting adjacent metal aircraft structures from corrosion — unlike standard sealants that provide only passive barrier protection.

Q: What specification does PPG P/S 870 meet?
A: P/S 870 meets MIL-PRF-81733 Type II, Class 1, Grade A specification for corrosion inhibitive polysulfide sealants.

Q: Is P/S 870 approved for aircraft fuel tank use?
A: Yes. P/S 870 is specifically formulated and tested for aircraft integral fuel tank sealing applications, providing the fuel resistance required for continuous immersion in aviation fuels.

Q: What is the MPN for PPG P/S 870 Quart Kit?
A: MPN is 0870B1-2MPQ4QT.

Q: How do I mix P/S 870 before application?
A: P/S 870 is a two-component system requiring mixing of the base and accelerator in the specified ratio. Follow the PPG P/S 870 TDS mixing instructions, pot life guidelines, and application parameters exactly for specification-compliant results.