Supex 508 LE – Low Surface Energy Plastic Adhesive

SUPEX 508 LE is a two-part (10:1) acrylic structural adhesive engineered specifically to bond Low Surface Energy (LSE) plastics—such as polypropylene (PP), polyethylene (PE, HDPE, LDPE), PTFE, and PVDF—without requiring surface primers or corona/flame treatments. It also bonds these plastics to dissimilar substrates, including metals (aluminum, steel), composites, and other engineering plastics.

Its key industrial applications include:

1. Automotive & Commercial Vehicle Manufacturing

• Interior Trim & Dashboards: Bonding polypropylene (PP) dashboard inserts, console modules, glove boxes, and door panel clips where standard adhesives fail to wet out.

• Under-the-Hood & Fluid Reservoirs: Assembling washer fluid tanks, overflow bottles, and battery casings made of HDPE/PP that require resistance to glycol, brake fluid, and engine oils.

• Bumper & Exterior Assemblies: Bonding brackets, sensor mounts, and reinforcements to PP/TPO (thermoplastic polyolefin) bumper fascias without read-through or heat distortion.

2. Plastic Fabrication & Tank Construction

• Chemical Storage & Fluid Tanks: Sealing and joint bonding of rotational-molded or welded HDPE and PP containment tanks, baffles, and drain spouts.

• Ducting & Piping Fixtures: Attaching flanges, brackets, and stiffening ribs to polyethylene or polypropylene ventilation ductwork and chemical-resistant exhaust manifolds.

• Wear Plates & Liners: Fastening ultra-low-friction PTFE or HDPE wear strips and chute liners directly to steel or aluminum backing frames.

3. Appliance & Consumer Electronics Assembly

• White Goods & Appliances: Assembling washing machine tub components, dishwasher impellers/housings, refrigerator liner trims, and drainage pump casings made of polyolefins.

• Power Tool & Equipment Housings: Bonding impact-resistant nylon, TPE grips, or PP outer clamshell cases.

• Battery Packs & Enclosures: Fastening cylindrical or prismatic cell holders and plastic outer housings in power equipment, e-bikes, and portable electronics.

4. Signage, Displays & Outdoor Graphics

• Fluted Plastic / Coroplast Signs: Assembling point-of-sale (POS) stands, corrugated PP display boxes, and mounting frames.

• Dissimilar Sign Assemblies: Attaching acrylic, polycarbonate, or metal standoff brackets to polyolefin backer boards cleanly without mechanical rivets.

5. Composite & Engineering Assemblies

• Thermoplastic to Metal Joints: Eliminating screws and rivets when attaching structural aluminum or carbon steel brackets directly to PP, PE, or FRP composite skins.

• Sporting Goods & Marine Components: Manufacturing and repairing kayak hulls, watercraft accessories, dock floats, and sporting gear molded from tough, chemically inert polyethylene.

Why Supex 508 LE Fits These Uses:

• No Primers Needed: Creates permanent, structural bond strength directly on PP and PE without flame, plasma, or chemical primers.

• Automotive Fluid & Water Resistance: Cured bond lines withstand ethylene glycol, power steering fluid, brake fluid, moisture, and high humidity.

• Fast Assembly Speed: 4–6 minute open working time with room-temperature curing makes it ideal for continuous assembly-line throughput.

1. What is SUPEX 508 LE?

SUPEX 508 LE is a two-part (10:1 mix ratio), room-temperature curing acrylic structural adhesive specially formulated to bond Low Surface Energy (LSE) plastics without surface primers or heat flame treatments.

2. Which plastics can SUPEX 508 LE bond?

It provides structural adhesion on hard-to-bond polyolefins, including:

• Polypropylene (PP)

• Polyethylene (PE, HDPE, LDPE)

• Fluoropolymers like PTFE and PVDF

• Engineering plastics including ABS, Polycarbonate, Acrylics (PMMA), and PVC

3. Does it bond plastic to metal or other materials?

Yes. In addition to plastic-to-plastic joints, SUPEX 508 LE bonds plastics to dissimilar materials such as aluminum, carbon steel, stainless steel, fiberglass/composites (FRP), glass, and wood.

4. Are primers, corona discharge, or flame treatments required?

No. Unlike conventional cyanoacrylates or standard epoxies that bead up on PP and PE, SUPEX 508 LE directly wets out the surface chemically, eliminating the need for primers or flame/plasma oxidation.

Application & Processing

5. How is SUPEX 508 LE dispensed and mixed?

It is packaged in a dual-component cartridge system (10:1 ratio by volume). It is dispensed using a matching manual or pneumatic dispensing gun with a static mixing nozzle to ensure homogenous blending.

6. What is the working time and fixture time?

• Working/Open Time: 4 to 6 minutes.

• Fixture Time: 17 to 19 minutes (parts can support light handling).

• Full Structural Cure: 24 hours at room temperature (~22°C–25°C).

7. How should surfaces be prepared before application?

Surfaces should be dry, clean, and free from oil, grease, mold-release agents, or dust. A simple wipe with a fast-evaporating solvent (like isopropyl alcohol or acetone) is typically sufficient.

8. Can it bridge gaps between ill-fitting parts?

Yes. It has a thixotropic gel consistency that resists sagging on vertical joints and can fill assembly gaps up to 5 mm without slumping.

Mechanical Strength & Durability

9. How strong is the bond on polypropylene and polyethylene?

It provides genuine structural joint strength, frequently exceeding the substrate’s yield point:

• Polypropylene (PP): ~1,075 psi lap shear strength

• Polyethylene (PE): ~1,100 psi lap shear strength (In many tests, the plastic itself deforms or tears before the adhesive bond line fails.)

10. What chemicals and fluids can it resist?

Once cured, the adhesive polymer resists exposure to:

• Automotive fluids (brake fluid, ethylene glycol, power steering fluid)

• Hydrocarbons (fuels, iso-pentane, motor oils)

• High moisture, water immersion, and environmental weathering

11. What is the operating temperature range?

SUPEX 508 LE performs reliably across a continuous temperature range of –55°C to +120°C.

Storage & Shelf Life

12. How should SUPEX 508 LE be stored?

Store cartridges refrigerated at or below 4°C (40°F) in original, unopened packaging to maintain stability and shelf life. Allow the cartridge to return to ambient room temperature before dispensing.

13. What is the shelf life?

When stored at the recommended refrigerated temperature (≤ 4°C), the product has a shelf life of 6 to 8 months from the date of manufacture.