Oatey 25-215 Plastic Seal Caulking and Sealing Compound – Gray, 10.3 oz Cartridge

The Oatey 25-215 Plastic Seal Caulking and Sealing Compound is a single-component, professional-grade polyurethane sealant formulated for industrial, mechanical, and construction applications. Designed to provide a durable, flexible, and waterproof seal, it functions as an effective lead substitute for caulking cast iron soil pipe joints and as a general-purpose joint and gap sealant across a broad range of substrates. The compound cures by air exposure to form a firm yet resilient elastomeric bond suitable for both interior and exterior use.

Details

• Manufacturer: Oatey (Hercules Chemical Division)
• Model Number: 25-215
• Product Name: Plastic Seal Caulking and Sealing Compound
• Product Type: Multi-purpose polyurethane-based sealant
• Form: Paste
• Container Type: Cartridge
• Container Size: 10.3 oz (305 mL)
• Net Weight: 1.2 lb (544 g)
• Color: Gray
• Odor: Slight, non-offensive
• Composition:
  • Propylene Carbonate
  • Titanium Dioxide
• Specific Gravity: 1.59
• Cure Time: 4–6 hours (air cure)
• Flash Point: 199°F (93°C)
• VOC Content: 4 g/L
• Flammability Rating: 1 (low)
• Adhesion Properties: Bonds to metal, masonry, concrete, wood, glass, ceramic, and most plastics
• Applicable Materials: Cast iron, masonry, wood, concrete, stone, metals, plastic, glass, aluminum, tile, vitreous china, and porcelain
• Temperature Resistance: Stable to 199°F (93°C) after full cure
• Chemical Resistance: Resistant to water, dilute acids, and weather exposure
• Toxicity: Non-toxic, does not contain TDI (toluene diisocyanate)
• VOC Classification: 0–4 g/L; meets low-VOC regulations
• Application Range: Indoor and outdoor sealing, ductwork, plumbing joints, structural expansion joints, and glazing applications

Technical Application

Oatey Plastic Seal is a multi-purpose polyurethane sealant suitable for professional use in plumbing, HVAC, and construction assemblies. It provides an effective waterproof and air-tight seal on cast iron soil pipe joints and can be used with or without oakum. The compound offers superior adhesion to most construction and plumbing substrates, including masonry, metal, wood, glass, and concrete. It air-dries to form a flexible seal that accommodates movement and vibration without cracking or shrinking. Multiple thin applications accelerate curing compared to a single heavy bead. The cured sealant exhibits strong resistance to weathering, pressure, and mechanical stress in both above- and below-grade environments.

Specifications

• Base Material: Polyurethane polymer blend
• Appearance: Gray paste
• Specific Gravity: 1.59
• Cure Time: 4–6 hours (air cure)
• Service Temperature Range: 0°F to 199°F continuous
• VOC Level: 4 g/L (compliant with low-VOC requirements)
• Flash Point: 199°F (93°C)
• Adhesion Strength: High – suitable for pressure-bearing joints after full cure
• Application Equipment: Standard caulking gun
• Compatibility: Metals, plastics, ceramics, concrete, and glass substrates
• Corrosion Resistance: Excellent – seals and protects exposed metal threads and surfaces
• Crack Resistance: Non-shrinking, flexible after cure
• Environmental Resistance: Weatherproof and water-resistant
• Contains TDI: No

Summary

The Oatey (Hercules) 25-215 Plastic Seal Caulking and Sealing Compound is a high-performance, single-component polyurethane sealant formulated for professional-grade sealing and caulking applications. Its air-curing, non-shrinking composition delivers durable adhesion to metal, masonry, and composite materials, making it suitable for cast iron joints, ductwork, glazing, and structural sealing in industrial and mechanical environments. The product provides a flexible, watertight seal resistant to corrosion, vibration, and temperature variation.