TAP Bond Coat Laminating Polyester Resin

TAP Bond Coat Laminating Polyester Resin

A reliable, economical solution for general-purpose fiberglass projects.

TAP Bond Coat Laminating Polyester Resin is a low-viscosity, thixotropic orthophthalic polyester resin specially formulated for fiberglass lay-ups using the spray-up or hand lay-up method. With a working time of 18–22 minutes and excellent handling on vertical surfaces, this resin is ideal for a wide range of fabrication and repair applications. It offers superior wet-out and roll-out performance for boats, tanks, car bodies, furniture, decks, garden ponds, sports gear, and more.

This resin is air-inhibited, meaning it cures to a tacky finish, which promotes strong interlayer adhesion without the need for sanding between coats. For final layers, simply add TAP Surface Curing Agent to achieve a cured finish. (Catalyst is sold separately.)

Key Features

• Low viscosity & thixotropic formula – Great for easy wet-out and vertical surface work

• Air-inhibited (tacky) finish – Allows bonding between coats without sanding

• Economical & fast-wetting – Ideal for large or frequent projects

• Pre-promoted for MEKP initiator – Cures at room temperature with standard catalyst

• Excellent strength & hardness development – Reaches high Barcol hardness early

Typical Uses

• Fiberglassing boats, tanks, car bodies, tools, and furniture

• Creating or reinforcing garden ponds, decks, and sports equipment

• Hand lay-up or spray-up manufacturing

• Filling fiberglass weave or prepping surfaces for cloth layup

Technical Specs (Uncured)

• Working Time (Pot Life): 18–22 minutes at 77°F

• Gel Time: 11–15 minutes

• Viscosity: ~575–675 cps

• Thix Index: ~3–5.0

• Peak Exotherm: ~300–360°F

• Specific Gravity: 1.21

• Monomer Content: <35%

• Catalyst Ratio (MEKP): 1–2.2% by weight

• Color Indicator: Changes from blue to neutral when catalyst is added

Cured Properties

• Tensile Strength: 8,958 psi

• Flexural Strength: 17,205 psi

• Tensile Modulus: 682,532 psi

• Flexural Modulus: 639,874 psi

• Barcol Hardness: 41

Laminated Properties (with Fiberglass)

• Tensile Strength: 15,215 psi

• Flexural Strength: 25,453 psi

• Barcol Hardness: 45

• Glass Content: 31.5–40%

• Post-Cure (example): 104°F for 16 hours or 230°F for 2 hours

Application Tips

• Apply between 65°F and 80°F in dry conditions—avoid sunlight during cure

• Surfaces must be clean, dry, and scuff-sanded

• Do not use on Styrofoam, redwood, cedar, oak, or oily woods

• Apply generously and work resin thoroughly into cloth

• Use TAP Surface Curing Agent in the final coat to fully cure the surface

• Clean tools with acetone before gelation

• Do not paint or epoxy over uncured laminating resin

Packaging & Availability

• Available in Pints, Quarts, Gallons, 5-Gallon Pails, and 55-Gallon Drums

• 5-gallon cans are in stock at all TAP Plastics stores – Contact your local TAP store for pricing

• 55-gallon drums are available via drop shipment – Email info@tapplastics.com for quote

• Catalyst sold separately

Safety & Storage

• Flammable. Irritant. Sensitizer. Keep away from heat, sparks, and open flame

• Store in closed containers below 75°F away from sunlight

• Use in well-ventilated areas with protective equipment

• Refer to Material Safety Data Sheet (MSDS) below