Ultra Lightweight Polyester Putty for Hardtops & Sandwich Bonding

Infinity Bond POLYFILL 4000 is an ultra lightweight polyester marine putty engineered for hardtop bonding, sandwich bonding, and lightweight composite assembly applications where reducing overall part weight is critical. Weighing less than 5 pounds per gallon, this advanced marine putty delivers dependable bonding performance while helping improve handling, efficiency, and structural stability in lightweight fiberglass assemblies. Designed for boat builders, marine fabricators, and composite manufacturers, POLYFILL 4000 pumps and trowels easily for reliable marine assembly and production performance.

Lightweight Bonding Advantages of POLYFILL 4000 Marine Putty

• Ultra Lightweight Formula: Weighs less than 5 lbs per gallon to help reduce overall part and hardtop weight.
• Designed for Hardtops & Sandwich Bonding: Ideal for lightweight composite assemblies and bonded marine structures.
• Excellent Clamping Flow: Flows evenly under moderate clamping pressure for consistent bond line coverage.
• Easy Pumping & Troweling: Pumps smoothly and spreads easily for efficient marine production workflows.
• Reliable Vertical Stability: Stays in place during assembly and mold repositioning without excessive movement.
• Low Exotherm Performance: Helps reduce heat buildup during curing for improved cosmetic quality and reduced surface defects.
• Higher Viscosity Options Available: Offered in thicker formulations for damming and specialized bonding applications.

Technical Specifications

• Series: POLYFILL 4000
• Type: Marine Putty
• Chemistry: Polyester Liquid Adhesive
• Gel Time: 28 Minutes
• Reaction Time: 45 Minutes
• Fixture Time: 73 Minutes
• Viscosity:
• 50,000 - 65,000 cps @ 2 RPM
• 18,000 - 28,000 cps @ 20 RPM
• Peak Exotherm: 150°F (65.6°C)
• Color: White
• Odor: Styrene
• Texture: Smooth
• Weight: 4.6 lbs/gallon
• Tensile Elongation: 8.2%
• Tensile Strength: 1,060 psi
• Flexural Strength: 6,960 psi
• Flexural Modulus: 357,000 psi
• Compressive Strength: 1,910 psi
• Lap Shear: 1,100 psi
• Heat Deflection: 150°F (65.6°C)
• Shore D Hardness: 40 - 50
• Package Size: 5-Gallon Pails
• Shelf Life: 3 Months

Note: Typical physical properties @ 75°F (24°C).

Recommended Applications

• Boat hardtop bonding applications
• Lightweight sandwich bonding
• Small composite part assembly
• Hand-laid fiberglass part production
• Marine assemblies requiring weight reduction
• Lightweight structural bonding applications
• Damming and controlled flow bonding applications