Sikaflex® PRO

Sikaflex® PRO is supplied throughout the world by Sika® and conforms to the most stringent sealant standards, for example:

• US Federal Specification TT-S-00230C, Type II, Class A.
• BS4254: For one part polyurethane based sealants for the building industry.
• JIS A 5758: For one part polyurethane based sealants for the construction industry.

Moisture curing polyurethane prepolymer.

Sikaflex® PRO has a shelf life of 12 months from the date of production, if it is stored in undamaged, original, sealed packaging, and if the storage conditions are met.

Sikaflex® PRO shall be stored in dry conditions, where it is protected from direct sunlight and at temperatures between +5 °C and +25 °C.

1.25 - 1.3 kg/l depending on colour

23 - 27 after 28 days (at +23 °C, 50% R.H.)

−30 °C to +70 °C (maximum +40 °C in water and temporarily +50 °C)

Permissible change in the joint width at ambient temperatures:

• above 0°C is ±30% of average joint width at the time of sealing
• below 0°C is a total of ±20% of average joint width at the time of sealing
• admissible total shear movement is 20% of joint width at the time of sealing

For the successful sealing of joints with Sikaflex® PRO it is essential that the following guidelines on joint configuration are observed:

General use:

• for joints up to 12 mm wide, width to depth ratio = 1:1
• for joints over 12 mm wide, width to depth ratio = 2:1

(minimum joint depth 8mm, maximum joint width 35mm).

An approximate rule of thumb for joints in precast concrete

Joint interval (metres) up to 2.0 2.0-3.5 3.5-5.0 5.0-6.5 6.5-8.0

Joint width (mm) 10 15 20 25 30

To ensure that the correct width to depth ratio is achieved and to provide a firm backing against which the sealant can be tooled off and also to prevent the sealant from adhering to the bottom of the joint, the space under the Sikaflex® PRO must be filled with a tight fitting, non-rotting, non-absorbent backing material eg. fibreboard combined with a bond breaking tape (eg. polypropylene or PVC) or, alternatively, an open cell polyurethane or closed cell polyethylene backer rod supplied by Sika. Open cell PU backer rod has the advantages of allowing moisture access to the front and back of the joint simultaneously facilitating faster curing. Also open cell PU backer rod is much more compressible than closed cell PE foams thus one diameter rod can be used in a much wider range of joints widths. Closed cell PE backer rod can cause bubbling in uncured sealant in rising temperature conditions if it's outer skin in punctured. It is essential that oil or tar impregnated backing materials are not used.

+5 °C to +40 °C, min. 3 °C above dew point temperature

2 mm in first 24 hours (+23 °C / 50% r.h.)

2 to 4 hours (+23 °C / 50% r.h.)

SIKAFLEX® ESTIMATING CHART

Quantities: a guide to Sikaflex® PRO quantities (for fillet work multiply metre runs per cartridge or 'unipac' by two).

Clean, sound, dry and free of oil, grease and surface contaminants such as form release agents, curing membranes and hydrophobic water repellents. Thoroughly remove all loose particles and dust.

Masonry / Brick / Concrete: Any loose particles or laitance should be removed with a rotary mechanical wire brush followed by blowing out with oil free compressed air. Use Sika cementitious or epoxy mortars for making good spalled or damaged joints.

Metals: Surface must be free of rust, scale or oxide films and should be degreased using Sika® Colma Cleaner, Acetone or M.E.K.

PRIMING

(Refer to Primer Selection Guide for detailed information. This is separate document).

Use Sika Colma Cleaner to remove uncured sealant from tools after first removing the bulk of the Sikaflex material with a scraper followed by a rag or paper tissue. Sikaflex Hand Cleaner will remove fresh and partially cured Sikaflex from the skin. Hardened material can only be removed mechanically.