Rubber tape is a Ethylene Propylene Rubber (EPR) based high-insulating voltage tape. It is used for electrical insulation, water sealing and mechanical padding and shaping.

Rubber tape is a splicing compound. The tape is applied to the splice with a light tension so that each layer presses tightly against the one beneath it. This pressure causes the rubber tape to blend into a solid mass.

In roll form, there is a layer of paper or treated cloth between each layer of rubber tape. This layer prevents the rubber from fusing while still on the roll. The paper or cloth is peeled off and discarded before the tape is applied to the splice.

Types
Rubber tapes are of various forms depending on various industrial and commercial applications.

• Natural rubber tape: provides superior adhesion in extreme temperatures. It is not affected by humidity and dampness. It yellows with age.
• Cohesive rubber tape: consists of one soft, uncured layer bonded to a cured, abrasion-resistant layer. Unique separator allows controlled removal at the user’s discretion. An airtight, waterproof, gas-tight seal is formed when the uncured layer is bonded to itself. It is used as a covering for communication and control cables.
• Double rubber tape: non-adhesive, self-bonding communication tape used for critical sealing and rejacketing. One layer of uncured compound permanently fused to an abrasion resistant layer of cured rubber.
• Self-amalgamating rubber: forms a solid piece of rubber. As the rubber cures and bonds it shrinks 3% which makes the tape excellent for forming watertight and air tight seals on most irregular surfaces.
• Butyl rubber tapes: these pliable, tacky adhesive and sealing tapes adhere to all metals, glass, plastics, concrete and porous surfaces. These tapes come in black or white.
• Rubber mastic tape: combines the higher voltage insulating capabilities of rubber tapes with the excellent moisture seal and padding of mastic. This tape is excellent for stretching and conforming in tight places.
• Hot melt rubber tape: features excellent shear adhesion to prevent flagging, and outstanding tear, burst, impact and transverse strength. It also provides good quick stick and controlled unwind properties.
• Rubber preformed tapes: hydrocarbon rubber based sealant can be formulated as hot melts, solvent release or preformed tapes using polybutenes, butyl rubber or polyisobutylene.

Features
Rubber tape provides a fast build of insulating materials and water seals on irregular joints and connections. It completely covers the entire joint or connection and makes a gasket –type seal onto the existing cable jacket. It prevents water seepage, even on very slick materials such as high-density polypropylene. Rubber tapes are typically overwrapped with vinyl tape, which forces the rubber flow and provides a slick abrasion-resistant outer surface. Most rubber tapes use a liner to prevent the tape layers from bonding or fusing in place on the roll. The liner is removed during application.

Applications
Some rubber tapes are made for special applications. These types are semi conducting and will pass electrical current, which presents a shock hazard. Also used for swimming costumes and pants edges.