The best glue for polystyrene
The best glue for polystyrene really depends on what you’re using the polystyrene for.
Expanded Polystyrene (EPS), to give it its full name, comes in a multitude of shapes and applications. It’s perhaps most notable as a key component of packaging, but more recently polystyrene has shown its use as a construction material. Its high insulation capacity and light weight provide a versatile option for modern building practices.Â
In this blog we cover the 4 best adhesives for bonding polystyrene and look at the pros and cons of each.
PVA adhesive
PVA adhesive (aka white glue or wood glue) can bond polystyrene to other porous materials such as timber, OSB board, ply, MDF, plasterboard, cardboard or fabric. And of course to polystyrene itself.
Pros of PVA:
- Ideal for many construction materials
- Water based so low H&S Risk
- Very easy clean up (use water)
- Strong bond
- Easy to spread via brush or roller
Cons of PVA:
- Long dry time
- Lower grades may not be waterproof
Our Timbond water resistant PVA is an excellent choice for working with polystyrene and comes in 1kg, 5kg or 25kg options or is also available to buy in bulk.
PU adhesive
PU adhesives come in two main formats:Â 1-component and 2-component.
1-component PU uses moisture to cure whereas with 2-component PU you add an activator to initiate curing. 
Construction uses PU adhesive extensively for bonding polystyrene to practically everything. This includes timber, most board materials such as cement board and plasterboard as well as to metal and GRP sheets.Â
SIPs panel manufacturers like working with PU adhesive because of its structural bond strength and waterproof properties. When bonding polystyrene with 1-component PU we recommend over-misting the glue line with water.
Pros of PU adhesive:
- Will bond to nearly all construction materials
- 1-component PU will expand slightly so works well with rough, textured or uneven surfaces
- Bonds in damp conditions
- Seriously strong bond
- Will bond to non-porous materials like metals, GRP, and cement boards
- Comes in different applications. Cartridges & bottles are perfect for small areas and bulk 25kg barrels for laminating applications
- Available in different set times
Cons of PU adhesive:
- Harder to clean up. Use solvent (Solvent 9)
- Waterproof once cured
- Some H&S risks / PPE maybe required
Timbond 5917 PU is a specialist adhesive developed for a wide range of applications and panel fabrication including the construction of structural insulated panels (SIPs) and architectural panels.
Spray Adhesive
Traditionally the propellant in spray adhesives would melt the polystyrene, which is obviously not ideal! Fortunately, today specialist products use a different propellant avoiding the problem altogether. 
These spray adhesives are very popular for insulation as they’re very fast and easy to apply.Â
Spray adhesives are also useful for bonding large blocks of polystyrene together for formwork or model making. Timbond Insulation adhesive, for example, is excellent for bonding polystyrene to fabrics, leather, carpet, foam, and to metal, hard plastic or plywood.
Pros of spray adhesive:
- Bonds to nearly all construction materials if clean and dust free
- Very fast drying, no cramp time
- Easy to apply – bonds large areas quickly
Cons of spray adhesive:
- Doesn’t work well with dusty surfaces
Hotmelts
Low-melt hotmelts and pressure-sensitive hot melts (applied via swirl applicators) – are used extensively in the manufacture of polystyrene insulated building components.
Hotmelt such as Timbond H509 (watch video here) is a safe, quick and cost effective option that bonds to nearly all construction materials including plasterboard, correx, ply and MDF.Â
Pressure sensitive hotmelts often get used for packaging and case making.
Pros of hotmelts:
- Bonds to nearly all construction materials
- Very fast drying
- Very low cost per sqm
- Perfect for repeat applications
Cons of hotmelts:
- Equipment often required
- Limited open time with some hotmelts
For further insights watch a demonstration video of Timbond H509 in use here.
So, there you have it – a range of adhesives suitable for most applications, although, of course, there are more options out there.
Contact Adkwik today
If you’re still not sure which adhesive is best for you then why not reach out to our technical team on 01223 412373, via our live chat or email our team online HERE and we’ll be happy to help.
