PRC-Desoto PR-1829 Class B Rapid Curing Windshield & Canopy Sealant - AMS G9-89BT

PR-1829 Class B is a two-part, epoxy cured Permapol P-3 polythioether compound. The uncured material is a low sag, thixotropic paste, suitable for application by extrusion gun or spatula. Unlike standard polysulfide windshield sealants, it can cure at low temperatures and is unaffected by changes in relative humidity. This sealant has excellent adhesion to common aircraft substrates.

Immediately before applying sealant to primed substrates, the surfaces should be cleaned with solvents. Contaminants such as dirt, grease, and/or processing lubricants must be removed prior to sealant application.

A progressive cleaning procedure should be employed using the appropriate solvents and new lint free cloth (reclaimed solvents or tissue paper should not be used). Always pour solvent on the cloth to avoid contaminating the solvent supply. Solvent may craze polycarbonate. Wash one small area at a time.

It is important that the surface is dried with a second clean cloth prior to the solvent evaporating to prevent the redeposition of contaminants on the substrate. Substrate composition can vary greatly. This can affect sealant adhesion. It is recommended that adhesion characteristics to a specific substrate be determined prior to application on production parts or assemblies. For adhesion to polysulfide sealants, PR-187 Adhesion Promoter must be used. For adhesion to polycarbonate and acrylic substrates, PR-142 Adhesion Promoter must be used.

Mixing instructions

PR-1829 Class B is supplied in a Semkit package. See the container for specific mixing instructions. The mix ratio is very critical.

Storage life
The storage life of PR-1829 Class B is at least 9 months when stored at temperatures below 80°F (27°C) in original unopened containers.