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How to choose a cyanoacrylate instant adhesive

Cyanoacrylate instant adhesives cure in seconds using ambient moisture and bond almost any material. This guide shows how to select by viscosity, cure time and substrate, and how to avoid the typical white haze known as blooming.

5 minStand: 2026-07Geprüft: Technical editors
View instant adhesives
2-2000 mPa·s
viscosity range
1-60 s
handling strength
-55 to +80 °C
service range
< 0.2 mm
ideal gap
Inhalt
  1. Choosing viscosity
  2. Substrate and primer
  3. Preventing blooming
  4. Frequently asked questions

Which viscosity suits your part?

Viscosity decides how the adhesive flows into the joint and how much positioning time you get. Thin grades (2‑5 mPa·s) wick into the tightest gaps by capillary action, while thick or gel grades (up to 2000 mPa·s) stay put and fill gaps on vertical or porous surfaces.

Rule of thumb: the tighter the fit and the more absorbent the material, the lower the viscosity you need. For rough surfaces, overhead work or gaps above 0.1 mm choose a gel that will not run and bridges the joint reliably.

Cyanoacrylate is a contact adhesive for thin bond lines. Large gaps above 0.3 mm cure poorly - a two-part structural adhesive is the better choice there.

Rubber, metal or plastic - which grade fits?

The substrate sets the chemistry. Standard ethyl cyanoacrylate bonds metal, rubber and most plastics extremely fast. For rubber and elastomers there are toughened, rubber-filled grades that better withstand vibration and peel loads.

  • Metal and rubber: ethyl cyanoacrylate cures in seconds on residual moisture; rubber-toughened grades raise peel strength.
  • Plastics such as ABS, PVC, PC: bond well; a flexible grade reduces stress cracking.
  • Hard-to-bond PE, PP, POM and silicone: only durable with an adhesion promoter (primer).
  • Porous materials (wood, leather, ceramic): medium to high viscosity, otherwise the adhesive soaks away.
An activator (accelerator) instantly cures excess adhesive and fillets - ideal on porous or acidic surfaces that would otherwise slow the reaction.
Adhesive selection

From activators to primers - the right accessory for every bond line.

Read the guide

How do I avoid white blooming and stringing?

White haze (blooming) forms when evaporating cyanoacrylate monomers react with airborne moisture and settle as a fine white film around the bond. It is most obvious on glossy, dark or optical parts.

  • Apply sparingly - one drop is usually enough; excess evaporates.
  • Ensure good ventilation so monomers are carried away instead of condensing.
  • Use low-bloom, low-odour cyanoacrylates with low vapour pressure.
  • Apply activator to lock down free monomers immediately.
  • Avoid bonding in high humidity over cold surfaces.
A cured white film can be wiped away carefully with a dry soft cloth or a dedicated cyanoacrylate cleaner. Solvents like acetone attack many plastics.

Frequently asked questions

Why does cyanoacrylate cure so fast?

The reaction is triggered by traces of moisture on the surface (anionic polymerisation). Even ambient humidity and the moisture on the parts is enough to reach handling strength in seconds.

How do I bond PE, PP or silicone?

These non-polar plastics barely bond untreated. An adhesion promoter (primer) makes the surface reactive, after which standard cyanoacrylate bonds reliably.

How should I store instant adhesive?

Cool and dry, ideally at 5‑8 °C in the sealed original bottle. This keeps the reactivity over its shelf life; use opened bottles up promptly.

Is cyanoacrylate temperature resistant?

Standard grades hold roughly -55 to +80 °C in continuous use. For higher temperatures up to around 120 °C there are dedicated heat-resistant formulations.

Looking for the right instant adhesive?

We supply cyanoacrylate adhesives in every viscosity, plus activator, primer and cleaner - matched to rubber, metal and plastic.

Full viscosity range

From thin wicking grades to gel for every joint.

Seconds to fix

Handling strength in 1 to 60 seconds.

Low-bloom options

Low-odour grades against white haze available.

Expert advice

We help with substrate and primer selection.

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