PPG PRC PR-716 Sealant Tack-Free Coating – 16 oz for Aerospace Sealant Finishing

PPG PRC PR-716 is a standard-specification sealant tack-free coating (also known as tack-free overcoat or fay surface coating) that is applied over freshly cured aerospace polysulfide and polyurethane sealants to eliminate the naturally sticky, tacky surface of the cured sealant and replace it with a smooth, non-stick, easy-clean finish. The tack of cured aerospace sealant exterior surfaces — while indicating good chemical integrity of the cured sealant — creates practical maintenance problems: tacky surfaces collect dirt, fuel residue, hydraulic fluid, and dust that is difficult to remove and can affect sealant inspection; they also cause aircraft skin panels to stick to each other during assembly and maintenance if sealant squeeze-out contacts adjacent panels.

PR-716 is applied by brush or spray over the completely cured sealant fillet, bead, or fay surface to deposit a thin, chemical-resistant coating that eliminates tack and provides a smooth surface that cleans easily during aircraft washing and maintenance operations. The PR-716 coated sealant surface remains flexible and adhered to the underlying sealant without cracking or delaminating through the thermal and mechanical cycling of aircraft service.

The 16 oz bottle provides a practical maintenance quantity of PRC PR-716 for application over sealant repairs, fuel tank sealing operations, and aircraft assembly sealing operations in maintenance hangar and production operations.

Technical Information

PRC PR-716 contains a coating chemistry — typically a thin polyurethane or polysulfide-compatible film former — that bonds to the surface of cured aerospace sealants to form a smooth, tack-free surface without compromising the elastomeric flexibility of the underlying sealant. The coating must remain flexible and adherent through the elongation and compression of the sealant during thermal cycling and structural movement — a rigid coating applied over flexible sealant would crack and delaminate, defeating its purpose as a protective surface treatment.

The chemical compatibility of PR-716 with both polysulfide and polyurethane sealants is an important design feature — aerospace facilities use multiple sealant chemistries for different applications, and a single tack-free overcoat that is compatible with both common sealant types simplifies inventory and reduces application error risk compared to requiring different tack-free coatings for each sealant type.

Apply PR-716 only to completely cured sealant. Applying tack-free coating to partially cured sealant traps residual cure gases in the sealant film and may interfere with the completion of the sealant cure reaction, potentially resulting in sealant defects. Allow the sealant to reach full cure per its application data sheet before applying PR-716.

Why Choose PRC PR-716?

• ✅ Tack Elimination — Converts sticky sealant surface to non-stick
• ✅ Easy Clean — Reduces contamination adhesion on sealant surfaces
• ✅ Compatible with Both Sealant Types — Polysulfide and polyurethane
• ✅ Remains Flexible — Does not crack over elastic sealant movements
• ✅ 16oz Maintenance Size — Right quantity for maintenance sealant finishing

Applications

PR-716 is applied over cured aerospace sealant fillets, fuel tank seams, structural joint sealant, and aircraft skin sealant applications to provide a tack-free, easy-clean surface finish in commercial and military aviation maintenance and production.

Frequently Asked Questions

Q: What is PRC PR-716?
A: PR-716 is a sealant tack-free coating applied over cured aerospace polysulfide and polyurethane sealants to eliminate tacky surface — creating a smooth, non-stick, easy-clean finish on sealed surfaces.

Q: MPN for PRC PR-716 16oz?
A: MPN is 0716XXXCA016PT.

Q: Why do aerospace sealants need a tack-free coating?
A: Cured aerospace sealants have a naturally tacky surface that collects contamination, sticks to panels, and is difficult to clean. PR-716 overcoat eliminates these practical problems without affecting the sealant’s sealing function.

Q: When should PR-716 be applied?
A: Apply only after the sealant is fully cured per its application data sheet. Applying over partially cured sealant can trap cure gases and cause sealant defects.

Q: Is PR-716 compatible with all sealant types?
A: PR-716 is compatible with both polysulfide and polyurethane aerospace sealants — simplifying inventory by replacing separate tack-free overcoats for each sealant chemistry.