Choosing the Right Plexus Structural Adhesive
When you need to bond metal, composites, or plastics without drilling, welding, or rivets, Plexus structural adhesives offer a powerful alternative. Used across transport, signage, fabrication, and industrial manufacturing, these methacrylate adhesives deliver exceptional strength, excellent gap filling, and fast curing even on minimally prepared surfaces.
Manufactured by ITW Plexus Adhesives, Plexus products are designed for real-world assembly environments where speed and reliability matter.
At Adhesive Supply Company, we regularly help customers choose between MA300, MA310, MA420, MA425, MA830, and MA832. This guide breaks down exactly what each grade is best for, so you can select the right adhesive first time.
Quick Comparison of Key Properties
(All values measured at 23°C from the Plexus EMEA selector guide.)
| Product | Working Time | Fixture Time | Tensile Strength | Best Known For |
|---|---|---|---|---|
| MA300 | 3–6 min | 10–13 min | 24–29 MPa | Fast assembly, high strength |
| MA310 | 15–18 min | 38–40 min | 20–24 MPa | Longer positioning time |
| MA420 | 4–6 min | 15–17 min | 19–21 MPa | Versatile all-rounder |
| MA425 | 28–30 min | 80–85 min | 18–22 MPa | Large assemblies |
| MA830 | 4–6 min | 15–17 min | 18–22 MPa | Primerless aluminium |
| MA832 | 12–14 min | 55–60 min | 19–24 MPa | Primerless aluminium with more open time |
Product Breakdown
Plexus MA300 (Fast, High Strength)
MA300 is a rapid-curing, all-purpose structural adhesive designed for production environments.
Why choose this grade
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Extremely fast working time
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High ultimate strength
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Excellent gap filling
Common substrates
Steel, aluminium, GRP, ABS, acrylic, PVC
Typical applications
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Metal brackets
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GRP panels
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Industrial housings
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General fabrication
Buy MA300 here
Plexus MA310 (More Time to Position)
MA310 offers similar strength to MA300 but with extended working time, making it ideal when alignment matters.
Why choose this grade
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Longer open time for accurate placement
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Strong structural performance
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Good all-round compatibility
Common substrates
Steel, aluminium, composites, most plastics
Typical applications
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Larger bonded panels
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Composite assemblies
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Multi-part fabrications
Buy MA310 here
Plexus MA420 (Reliable General Purpose)
MA420 is one of the most widely used Plexus structural adhesives, valued for its balance of speed, toughness, and versatility.
Why choose this grade
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Fast fixture
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Broad material compatibility
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Excellent everyday structural bonding
Common substrates
Metals, GRP, ABS, PVC, polycarbonate
Typical applications
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Vehicle body panels
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Signage fabrication
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Composite enclosures
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Plastic-to-metal bonding
Buy MA420 here
Plexus MA425 (Extended Working Time)
If you’re bonding large structures, MA425 gives you nearly 30 minutes of working time.
Why choose this grade
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Long open time
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Ideal for complex assemblies
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Strong structural performance
Common substrates
Metals, composites, thermoplastics
Typical applications
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Large GRP panels
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Structural frameworks
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Multi-component builds
Buy MA425 here
Plexus MA830 (Primerless Aluminium, Fast Cure)
MA830 is engineered specifically to bond aluminium without primer while still curing quickly.
Why choose this grade
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Primerless aluminium bonding
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Rapid fixture
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High strength
Common substrates
Aluminium, steel, GRP, composites
Typical applications
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Aluminium frames
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Transport panels
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Fabricated metal assemblies
Buy MA830 here
Plexus MA832 (Primerless Aluminium with More Open Time)
MA832 offers the same aluminium capability as MA830 but with extended working time.
Why choose this grade
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Primerless aluminium
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More positioning time
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Strong, durable bond
Common substrates
Aluminium, steel, GRP, composites
Typical applications
-
Larger aluminium structures
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Mixed-material assemblies
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Complex builds needing alignment
Buy MA832 here
Why Manufacturers Switch to Plexus Structural Adhesives
Across all grades, Plexus structural adhesives provide major advantages over mechanical fixings:
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Bond dissimilar materials
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No drilling or welding
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Reduced stress concentrations
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Cleaner finished appearance
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Excellent impact resistance
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Faster assembly
If you’d like a technical overview of methacrylate chemistry, Wikipedia offers a useful background resource:
https://en.wikipedia.org/wiki/Methacrylate
How to Choose the Right Grade
A simple guide:
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Need speed? MA300 or MA830
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Need more working time? MA310, MA425, or MA832
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Want a versatile all-rounder? MA420
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Bonding aluminium without primer? MA830 or MA832
Working time is usually the most important factor. Strength differences between these Plexus structural adhesives are relatively small in real-world applications.
PC120 Primer Guide (Typical Requirements)
When should PC120 primer be used?
PC120 is most commonly applied to bare aluminium or steel when assemblies will face moisture, temperature cycling, or long-term outdoor exposure. In controlled indoor environments with clean, abraded metal, many users bond successfully without primer.
MA830 and MA832 are specifically formulated to bond aluminium without primer. For MA300, MA310, MA420, and MA425, PC120 primer is optional on metals and mainly used when maximum long-term durability is required or surfaces are difficult to prepare. GRP and most plastics generally do not require primer with any of these grades.
Based on ITW Plexus application guidance and common fabrication use cases. Buy Plexus PC120 here
| Adhesive | Aluminium | Steel | GRP / Composites | ABS / Acrylic / PVC | Notes |
|---|---|---|---|---|---|
| MA300 | Sometimes | Sometimes | No | No | Primer may improve durability on bare metals |
| MA310 | Sometimes | Sometimes | No | No | Same behaviour as MA300, longer open time |
| MA420 | Sometimes | Sometimes | No | No | General-purpose grade, primer optional on metals |
| MA425 | Sometimes | Sometimes | No | No | Large assemblies, primer improves metal longevity |
| MA830 | ❌ No | Sometimes | No | No | Designed to bond aluminium without primer |
| MA832 | ❌ No | Sometimes | No | No | Primerless aluminium with longer working time |
Key:
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❌ = Primer typically NOT required
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“Sometimes” = Depends on surface condition, environment, and durability expectations
Accessories Required for Plexus Adhesives
All Plexus cartridges require manual dispensing guns and static mixing nozzles to ensure proper 2-part mixing and application. Without these, the adhesive can’t be used correctly.
To make things simple, here’s what you’ll need:
🔫 Manual Dispensing Guns (Required)
Each cartridge size needs a matching gun:
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50ml cartridges
👉 Manual 50ml dispensing gun
Buy here: https://www.adsupply.co.uk/product/50ml-1-1-ratio-manual-dispensing-gun-economy/ -
400ml cartridges
👉 Manual 400ml dispensing gun
Buy here: https://www.adsupply.co.uk/product/plexus-400ml-1-1-ratio-manual-dispensing-gun/ -
380ml cartridges
👉 Manual 380ml dispensing gun
Buy here: https://www.adsupply.co.uk/product/plexus-380ml-applicator-cartridge-gun/ -
490ml cartridges
👉 Manual 490ml dispensing gun
Buy here: https://www.adsupply.co.uk/product/plexus-490ml-manual-applicator-gun/
(All Plexus MA300, MA310, MA420, MA425, MA830, and MA832 cartridges require one of the above, depending on pack size.)
🧪 Static Mixing Nozzles (Also Required)
Each cartridge also needs a static mixer nozzle to properly blend the adhesive components during dispensing.
👉 Plexus-compatible static mixing nozzles
We recommend keeping spare nozzles on hand, especially for larger jobs or multiple assemblies.
Need Help Selecting?
Every project is different. Substrates, joint size, ambient temperature, and assembly method all influence performance.
If you’re unsure which of these Plexus structural adhesives fits your application, contact Adhesive Supply Company with details of what you’re bonding. We’re happy to help you choose the right product and avoid costly trial-and-error.
