Swelling Adhesive Mastic
Newton 306 SwellMastic is a high-quality, firm, fast curing, swellable, single-component, polymeric adhesive sealant.
The special composition of Newton 306 SwellMastic makes the sealant start to swell when in contact with water (to about 150% of original size). The sealant has high elasticity and high adherence and it develops a strong adhesive tensile strength immediately after application.
The first swelling is time delayed which allows Newton 306 SwellMastic to be applied to slightly damp surfaces.
Newton 306 SwellMastic is suitable for bonding Newton 303 PolyProof water bars to concrete and steel as well as being a sealant for service protrusions through the structure.
Typical Applications
- As a swelling adhesive for the installation of Newton 303 PolyProof hydrophilic water bars and Newton 305 ActiveJoint movement water bars.
- Sealing of service protrusions through the structure.
- To further waterproof around pipes sealed with Newton 307 PipeSeal.
Key Benefits
- Very high resistance to water pressure.
- Delayed swelling – will not swell during the installation process or during the concrete cure.
- Swells up to 150 times its original size to quickly seal leaks at joints in the structure.
- Very resistance to the high alkalinity of concrete.
- Maintains very high elasticity and tensile strength, even when swollen.
- Age resistant, no embrittlement.
Suitable Substrate and Materials
- Concrete.
- Steel.
- Plastic.
- Rubber.
System 300 – Waterproofing of Concrete Structures- View Full Product Range
View Newton Waterproofing Systems Catalogue
For a hard copy of this catalogue please e-mail your details
to info@newton-membranes.co.uk
Further Information
For further information or to place an order, please ring 020 7237 1217 or e-mail info@newton-membranes.co.uk. For a list of registered installers in your area, fill out our online form Request List of Registered Installers



