Mastic Tape –
Self-Amalgamating Sealing Tape
Butyl rubber self-amalgamating mastic tape for cold-applied moisture-proof sealing in cable joints and terminations. No primer, no heat — just hand pressure. Supplied in insulating and semi-conductive grades.
Overview
Mastic tape is a butyl rubber-based self-amalgamating tape that forms a homogeneous, void-free seal when applied under hand pressure — no heat required. Unlike conventional PVC tapes that rely on adhesive and can delaminate in wet or hot conditions, mastic tape cold-flows to fill all voids, irregularities and gaps at cable surfaces. Over time, the layers merge completely into a solid rubber mass that is indistinguishable from a moulded seal. It is a standard component in VIKCHEM's cable jointing and termination kits and is also available separately for cable repair and standalone sealing applications.
Available Types
Insulating Mastic Tape
Black butyl rubber tape used as moisture sealant and void filler at cable jacket transitions, screen cutbacks and connector interfaces in cable joints and terminations.
Semi-Conductive Mastic Tape
Conductive variant for re-establishing cable screen continuity at repair and joint positions. Bonds to XLPE and EPR insulation for screen restoration.
Key Features
- Cold-applied — no heat gun or special tools needed
- Self-amalgamating — merges into a solid homogeneous mass under hand pressure
- Bonds directly to XLPE, PVC, EPR and PILC cable jackets without primer
- Excellent moisture and water vapour barrier — prevents ingress in underground conditions
- High elongation (>500%) — accommodates cable movement without cracking or delamination
- Dielectric strength >3kV/mm — suitable for insulating applications in cable kits
- UV and ozone resistant — suitable for outdoor and aerial cable connections
- Supplied interleaved on release film for easy, clean application
Applications
Cable Joint Sealing
Moisture-proof seal at cable jacket transitions within heat shrink jointing kits.
Termination Kits
Sealing the cable jacket / heat shrink interface at cable termination assemblies.
Screen Restoration
Semi-conductive grade re-establishes cable screen continuity at repair points.
Outdoor Weatherproofing
Sealing overhead cable connectors and dead-end fittings against rain and UV.
Pipe Sealing
Sealing cable entry points into junction boxes, switch rooms and electrical panels.
Battery Terminal Protection
Moisture and corrosion protection at battery terminals in UPS and telecom DC systems.
