Isophthalic Resin Quart

Isophthalic Polyester Laminating Resin

Isophthalic Polyester Resin is a professional-grade laminating resin formulated for demanding fiberglass and composite applications where strength, durability, and long-term performance are critical. This medium-reactivity, low-profile isophthalic resin is promoted for room-temperature curing with MEKP catalyst and is widely used throughout the marine, transportation, industrial, and composite manufacturing industries. 

Compared to general-purpose orthophthalic polyester resins, Isophthalic provides significantly improved resistance to water intrusion, chemical exposure, corrosion, heat, and impact. The isophthalic formulation also creates stronger bonds with fiberglass reinforcements, resulting in laminates that are more durable and longer lasting. In many corrosive environments, isophthalic laminates can provide performance comparable to significantly more expensive specialty resin systems. 

Product Features

• Premium isophthalic polyester laminating resin
• Excellent fiberglass wet-out characteristics
• Superior chemical and corrosion resistance
• Outstanding water resistance
• Improved impact resistance
• Higher heat resistance than general-purpose polyester resin
• Enhanced adhesion to fiberglass reinforcement
• Reduced resin drainage for uniform laminates
• Low-profile formulation for improved laminate appearance
• MEKP catalyst compatible
• Available for hand lay-up and spray-up applications 

Common Applications

• Boat hull construction and repair
• Marine fiberglass fabrication
• Fiberglass molds and tooling
• Storage tanks and tank linings
• Pipes and industrial vessels
• Truck and automotive body panels
• Bridge and infrastructure components
• Industrial floor coatings
• General fiberglass composite manufacturing 

Performance Benefits

The advanced isophthalic formulation provides:

• Stronger fiberglass-to-resin bonding
• Improved laminate durability
• Better resistance to moisture absorption
• Greater resistance to harsh chemicals
• Reduced print-through
• Lower resin consumption through rapid wet-out
• Lighter, stronger finished parts 

Catalyst Information

Typical gel times at approximately 72°F:

• 0.5% MEKP: 25–30 minutes
• 1.0% MEKP: 16–19 minutes

Actual gel times will vary based on temperature, catalyst percentage, resin mass, and working conditions. 

FDA Compliance

 Isophthalic Resin is manufactured from components listed under FDA regulations for repeated food-contact applications, making it suitable for certain approved industrial and commercial uses where food-contact compliance is required. 

Storage Recommendations

Store resin in a cool, dry location away from direct sunlight and heat sources. Never return catalyzed resin to an original container, as contamination can cause premature curing and product loss. 

Need help selecting catalyst quantities or fiberglass reinforcement materials? Contact Fiberglass Supply Depot at 772-464-0808 and our team will be happy to assist.

Click For MEK-P Catalyst Chart