PPG PR1773B-2 (1-ea-S654)

PR-1773 Class B Access Door Sealant

Overview

PR-1773 Class B is a two-part, manganese dioxide-cured polysulfide sealant designed for aerospace applications requiring low-adhesion, corrosion-inhibitive sealing. It is commonly used as an access door sealant and for form-in-place (FIP) gasket fabrication. The material cures at room temperature to form a removable seal that resists corrosion on aluminium alloys and dissimilar metal joints while remaining flexible across a wide service temperature range.

Key Technical Specs

• Product Type: Two-part polysulfide sealant (Class B)
• Cure System: Manganese dioxide cured
• Application Form: Thixotropic paste (non-sag)
• Mix Ratio: As specified per kit (Part A / Part B)
• Service Temperature: -54°C to 121°C
• Intermittent Exposure: Up to 149°C
• Appearance: Part A (red), Part B (dark red/black)
• Hardness: ~55 Shore A (typical cured)
• Specific Gravity: ~1.65 (cured)

Approvals & Specifications

• Conforms to AMS 3284 Class B test methods
• Qualified for aerospace structural sealing applications
• Used on anodized aluminium, titanium, stainless steel, and primed substrates

Typical Applications

• Aerospace access door sealing
• Form-in-place (FIP) gasket fabrication
• Corrosion barrier between dissimilar metals
• Sealing of aircraft panels and maintenance access points
• Protection of aluminium alloys from galvanic corrosion

Key Features & Benefits

• Low adhesion for removable access seals
• Excellent corrosion inhibition between metal interfaces
• Flexible, durable seal across wide temperature range
• Good resistance to fuels, lubricants, and hydraulic fluids
• Non-sag formulation suitable for vertical and overhead application
• Maintains performance under thermal cycling conditions

Application Guidelines

• Clean substrate thoroughly with approved solvent before application
• Remove all contaminants including grease, oil, and processing residues
• Apply using extrusion gun or spatula
• Mix Part A and Part B separately before combining
• Thoroughly mix entire contents before application
• Allow curing at room temperature (typical tack-free and full cure per process conditions)

Performance Characteristics

• High peel strength with adhesive mode of failure on approved substrates
• Resistant to galvanic corrosion in dissimilar metal joints
• No cracking after flex testing at low temperatures
• Stable under fluid immersion and thermal exposure testing

Compatibility & Safety Notes

• Designed for aluminium, titanium, stainless steel, and primed surfaces
• Surface preparation critical for adhesion performance
• Refer to Safety Data Sheet before use
• Industrial use only

Storage & Shelf Life

• Shelf life: Minimum 9 months (below 27°C, unopened containers)
• Frozen cartridge storage: limited shelf life under controlled conditions
• Store in original sealed containers

Why This Product is Used in Aerospace Maintenance

• Enables removable yet corrosion-protective sealing of access panels
• Reduces galvanic corrosion in mixed-metal assemblies
• Reliable performance under vibration and thermal cycling
• Widely used in certified aerospace sealing systems

Practical Suggestions for Maintenance Teams

• Strictly control surface cleanliness before application
• Ensure correct mixing ratios to maintain cure performance
• Avoid contamination during solvent cleaning steps
• Apply in controlled bead thickness for uniform sealing

Manufacturer / Product Codes

• Product Name: PR-1773 Class B
• Type: Aerospace polysulfide access door sealant
• Specification: AMS 3284 Class B
• Manufacturer reference: PPG Aerospace