When to use Bond Breaker Tape?
Used in joint sealing applications, Bond Breaker Tape stops joint sealants from adhering to surfaces and preventing “3 sided adhesion” which limits the sealants ability to accommodate movement. Bond breaker Tape is black self adhesive polyethylene tape that has excellent conformability to irregular surfaces.
What is bond breaking tape?
3M™ Bond Breaker Tape 8891 is a black polypropylene tape that provides a unique. way to break the bond of sealant between the cement joints. The tape does not allow the sealant to adhere to the tape backing allowing the sealant joint to only adhere to the two cement sides. Construction.
What is a bond breaker in waterproofing?
The definition of a bond breaker according to AS 3740 is: “A system that prevents the membrane bonding to the substrate, bedding or lining.”
Why is a bond breaker important?
Bond breakers minimize the varying loads at the time of moving or stripping of precast components and ensures their easy separation from the casting molds. Generally bond breakers are also designed to provide curing function, to ensure effective curing of casting molds as well as the top surface of precast members.
What is the purpose of a bond breaker?
A bond breaker is the layer of separator substance applied in different forms between adjoining solid surfaces. It is used to ensure that there is no adhesive molecular bond between the surfaces.
Is polyurethane a bond breaker?
Polyurethane sealants are not bond breakers, where they do not allow the membrane to release when subjected to movement. These are termed as fillet joints, and therefore do not comply with AS3740 3.13. 7 requirements. Neutral cure silicone, non-paintable polyurethanes or vinyl tapes are used as bond breaker materials.
What does backer rod look like?
Backer rods are usually round, flexible lengths of foam that are used as a “backing” in joints or cracks to help control the amount of sealant/caulking used and create a back stop. Besides shape, an important attribute is the variety of foam cell structure types: closed cell, open cell, and bi-cellular.
Where to place 3M bond breaker tape 8891?
If the sealant becomes attached to the filler, it cannot seal the joint against water and debris. To ensure free movement in the joint, bond breaker tape is placed between the joint sealant and joint filler. 3M™ Bond Breaker Tape 8891 features a strong polypropylene backing with a synthetic rubber resin adhesive.
What kind of adhesive is bond breaker tape made out of?
The tape features a polypropylene backing with a synthetic rubber resin adhesive with high sealant release performance. Good dispensing properties make it suitable for on-site applications.
Why do you need bond breaker tape for joint sealant?
Joint sealant must allow free extension and compression during the opening and closing of joints to work properly. If the sealant becomes attached to the filler, it cannot seal the joint against water and debris. To ensure free movement in the joint, bond breaker tape is placed between the joint sealant and joint filler.
What kind of tape to use on backer rod?
Bond breaker tape is used in joints that are too shallow to install a backer rod. This type of tape is made of polyolefin or Teflon and provides a non-stick surface to prevent sealant 3-sided adhesion.