Sikaflex® PRO
Sikaflex® PRO is a 1-component, thixotropic, polyurethane based joint sealant. It cures under the influence of atmospheric moisture to form an elastomeric material with adhesive properties. In some cases without the need for priming of the substrate.
- New Sikaflex® PRO will bond well to well cleaned Sikaflex® PRO.
- Excellent adhesion on all cement materials, brick ceramics, polyurethane, epoxy, most polyester, most metals and most timbers.
- High durability.
- Good weathering resistance.
- Non-sag on vertical and soffit joints up to 30 mm width.
- Short skinning time.
- Short cut off string, even after storage.
- Ready for immediate use - no mixing, saves time.
- No potential mixing errors or waste due to mixed quantities being greater than required.
- Non-corrosive.
- Can be painted over with many water, solvent and rubber based paints (preliminary tests recommended).
- Approved for use in potable water (AS4020:2005)
- Resistant to bacterial attack.
Usage
As an elastic joint sealant for:- Expansion joints in buildings and civil structures above and below ground.
- Construction joints.
- Joints in precast concrete elements.
- External walling and cladding joints.
- Infill panel joints.
- Curtain walling.
- Sanitary installations.
- Sealing around window and door frames.
- Flexible draught proofing.
- Sealing penetrations in walls or floors for ducts, piping etc.
- Retaining walls.
Advantages
- New Sikaflex® PRO will bond well to well cleaned Sikaflex® PRO.
- Excellent adhesion on all cement materials, brick ceramics, polyurethane, epoxy, most polyester, most metals and most timbers.
- High durability.
- Good weathering resistance.
- Non-sag on vertical and soffit joints up to 30 mm width.
- Short skinning time.
- Short cut off string, even after storage.
- Ready for immediate use - no mixing, saves time.
- No potential mixing errors or waste due to mixed quantities being greater than required.
- Non-corrosive.
- Can be painted over with many water, solvent and rubber based paints (preliminary tests recommended).
- Approved for use in potable water (AS4020:2005)
- Resistant to bacterial attack.
Packaging
310 ml cartridge, 12 cartridges per box
600 ml foil pack, 20 foil packs per box
Sika Primers are supplied in 250 ml and 1 litre cans (Flammable)
Sika Activator 205 supplied in 250 ml and 1 litre cans (Flammable)
Sika Colma Cleaner is supplied in 1 litre and 20 litre cans (Flammable)
Colour
Grey, dark grey, black, white
Colours are shown as a guide only. For true representation of colours please contact your local Sika® office or Technical Sales Department.
Product Details
APPROVALS / CERTIFICATES
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.
Composition
Moisture curing polyurethane prepolymer.
Shelf life
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.
Storage conditions
Sikaflex® PRO shall be stored in dry conditions, where it is protected from direct sunlight and at temperatures between +5 °C and +25 °C.
Density
1.25 - 1.3 kg/l depending on colour
Shore A hardness
23 - 27 after 28 days (at +23 °C, 50% R.H.)
Movement capability
Refer Joint Design section. |
Elastic recovery
>80% | (JIS A 5758 1992) |
Tear strength
>0.2 MPa @ 50% elongation @ +23 °C | (JIS A 5758 1992) |
Service temperature
−30 °C to +70 °C (maximum +40 °C in water and temporarily +50 °C)
Chemical resistance
Long Term | Mid Term | Low to Very Low |
Water | Mineral oils | Organic solvents |
Sea water | Vegetable oils | Paint diletents |
Dilute mineral acids | Fats | Strong acids |
Dilute mineral alkalis | Swimming / Spa | Strong Alkalis |
Domestic sewage | Pool water | |
Fuel oils |
Joint design
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.
Application
Ambient air temperature
+5 °C to +40 °C, min. 3 °C above dew point temperature
Curing rate
2 mm in first 24 hours (+23 °C / 50% r.h.)
Skinning time
2 to 4 hours (+23 °C / 50% r.h.)
Consumption
SIKAFLEX® ESTIMATING CHART
Quantities: a guide to Sikaflex® PRO quantities (for fillet work multiply metre runs per cartridge or 'unipac' by two).
Joint Size in MM | Litre Sikaflex® PRO per metre run | Metre run per cartiridge (310ml) | Metre run per cartiridge (600ml) |
5x5 | 0.025 | 12.4 | 24 |
5x10 | 0.050 | 6.2 | 12 |
5x15 | 0.075 | 4.2 | 8.0 |
10x10 | 0.100 | 3.1 | 6.0 |
10x15 | 0.150 | 2.0 | 4.0 |
10x20 | 0.200 | 1.55 | 3.0 |
10x25 | 0.250 | 1.24 | 2.4 |
15x10 | 0.150 | 2.06 | 3.9 |
15x15 | 0.225 | 1.35 | 2.7 |
15x20 | 0.300 | 1.04 | 2.0 |
15x25 | 0.375 | 0.82 | 1.6 |
15x30 | 0.450 | 0.69 | 1.3 |
15x40 | 0.600 | 0.51 | 1.0 |
20x10 | 0.200 | 1.55 | 3.0 |
20x15 | 0.050 | 1.04 | 2.0 |
20x20 | 0.400 | 0.78 | 1.5 |
25x12.5 | 0.310 | 1.00 | 2.0 |
25x15 | 0.380 | 0.81 | 1.6 |
25x20 | 0.500 | 0.62 | 1.2 |
25x25 | 0.630 | 0.50 | 0.9 |
30x15 | 0.450 | 0.69 | 1.3 |
30x20 | 0.600 | 0.51 | 1.0 |
30x25 | 0.750 | 0.42 | 0.8 |
40x20 | 0.800 | 0.39 | 0.8 |
40x25 | 1.000 | 0.31 | 0.6 |
40x30 | 1.200 | 0.26 | 0.5 |
SUBSTRATE PREPARATION
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).
CLEANING OF EQUIPMENT
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.