Primer for porous joints


Polyprime PS is a single component solvent based adhesion promoting primer for movement and control joints in porous substrates like concrete, block work, asbestos and timber. The primer forms a chemical bridge between the concrete surface and the sealant which is applied into the joint.


  • Porous surfaces such as concrete, cement brickwork, gypsum board, timber and stone
  • Stabilizes and seals joint surface particularly in harsh environments such as areas subjected to heavy traffic, saline water, fuel or oil spillage areas

This TDS is applicable for the United Arab Emirates only. Please contact your local Polybit sales office for the available TDS in your region


Joint Preparation

The joint surface must be clean, dry and free from oil, loose particles, cement laitance and other contaminants which may affect the adhesion. A thorough wire brushing, grinding, sand blasting or solvent cleaning may be required to expose a clean and sound substrate. On painted surfaces all loosely adhering paint must be removed (contamination will reduce the strength of the bond), if in doubt remove all previous decorations. To optimize adhesion of both the primer and the sealant, remove all round or sharp edges and corners. Ensure that the surface is absolutely dry before the primer is applied.


Polyprime PS shall be applied to clean, dry surface prior to the installation of backer rod or bond breaking tape. Polyprime PS can be applied by a brush in one thin and uniform coat. The sealant shall be applied only after the primer becomes tackfree. A recoat of the primer is required to be applied on the surfaces if the sealant application gets delayed by more than 3 hours after application of the primer. For obtaining a clean and neat finish, masking tape shall be applied on both the edges of the groove before applying the primer and shall be removed once the sealant installation is complete.


Clean all tools with Polysolvent immediately after use. Hardened materials can be removed mechanically only.