Abrasion resistant, epoxy modified, polyurethane joint sealant

flexothane® EPU is a two-component abrasion resistant, tough, epoxy-modified polyurethane joint sealant for use where limited joint movement is expected and resistance to chemical spills is a prerequisite.

Uses

Low movement joints in:

  • Factory and warehouse floors
  • Chemical plants
  • Culverts
  • Spillways
  • Commercial centres
  • Petrol station forecourts
  • Airport aprons and hangars
  • Fuel depots
  • Bunded areas
  • Sea walls
Advantages
  • Tough material, withstands heavy traffic, high abrasion resistance for use in culverts and sea walls
  • Good chemical resistance to a range of chemicals
  • Can be installed to a flush finish to protect the joint arises in factory or warehouse applications
  • Applied to vertical and horizontal joints
Joint Geometry

flexothane® EPU can be used for joints from 5 mm to 50 mm. Where the joint width is less than 25 mm and the sealant is supported on the concrete, the depth must not be less than 15 mm. In instances where a flexible joint filler is used, the minimum depth should be 20 mm.

 

Surface Preparation

Thorough preparation of joints is essential if a satisfactory seal is to be obtained. For concrete surface all traces of dust, laitance, mould oil, any previous sealant and all other foreign material must be removed by mechanical grinding, followed by blowing out with dry oil free compressed air. All surfaces must be completely dry.

Typical Physical Properties
 Form Two-component
Base White paste
Curing agent Grey paste
Mixed colour Light grey
M.A.F. 10%
Reaction Chemical cure
Pot life 1 hour at 20 °C
Light traffic 24 hours
Heavy traffic 48 hours
Shore A hardness (at 20 °C) ± 70
Chemical Resistance (Occasional Spillage)
 Alcohols High
Alkalis High
Chlorinated hydrocarbons Low
Mineral oil High
Hot detergent solutions @ 60 °C High
Hydraulic fluid (Skydrol) Poor
Live steam High
Mineral acids (25%) High
Vegetable oils High
Kerosene High
Xylene Low
Coverage for Estimating Purposes
Joint size in mm  Litre per metre 
10 x 15 0,150
20 x 10 0,200
20 x 15 0,300
20 x 25 0,500
25 x 25 0,625
30 x 25 0,750
30 x 30 0,900
40 x 25 1,000
40 x 40 1,600
50 x 25 1,250
50 x 50 2,500

On average 1 x 250 ml tin of epidermix® 326 is sufficient for 6 tins/12 litres of sealant.

No allowance has been made for wastage or to varying porosity of the concrete to which it is being applied.

Protection of Surfaces

Masking tape applied to areas adjacent to the joint will protect them from smearing and enable the joints to be finished to a neat line. The tape should be applied after the joint has been prepared, prior to any priming or sealing operation and removed after all finishing and tooling operations have been completed, but before the sealant has cured.

Bonding / Priming

Joints to be sealed using flexothane® EPU do not usually require priming. The exception being where the sealant is subject to contstant immersion. In this circumstance, use epidermix® 326 as the primer. The primer film must be allowed to lose its solvent (about 30 minutes drying) before the sealant is applied. The primer open time is 4 hours. If, however, the primer is allowed to dry longer than 6 hours, the surface must be re-ground and re-primed.

Back-up Material

duracord is a self-releasing material, but if softboard is used as the joint filler, a plastic strip bondbreaker must be placed on the filler surface before the sealant is applied. Under a pressure head of liquid, backing cord should be at least 2,5 times greater in diameter than the width of the joint slot.

Mixing

Add the activator to the base and mix thoroughly using a suitable paddle attached to a slow-speed drill (approximately 300 r/min). Mixing should take at least 5 minutes.

Note: If the material is not mixed properly it’s performance will be impaired.

Coverage

Refer to table for estimated coverages. 

Application

Application to primed surfaces can be by hand operated or pneumatic gun.

Cleaning

Tools and mixing equipment should be cleaned immediately after use, and before the material has set with abe® super brush cleaner followed by washing with soap and water.

Protection on Completion

The finished sealant should be protected from traffic until the sealant has fully cured. Overpainting of the sealant is not recommended because of the inability of paint films to accept movement. 

Application Temperature

Surface and ambient temperature must be at least +5 °C and rising, ideally between 20 °C and 30 °C. Lower temperatures will affect the curing period.  

Model Specifications

Two-component, gun-grade, epoxy-modified polyurethane sealant for factory floors where small hard wheels are used, and abrasion and chemical resistance is required.

The sealant will be flexothane® EPU, a two-component, epoxy-modified polyurethane applied in accordance with the recommendations of a.b.e.® Construction Chemicals. The sealant will have a Shore A hardness of ±70 and a movement accommodation factor of 10%.

Packaging

flexothane® EPU is supplied in 2 litre kits.

Handling & Storage

flexothane® EPU has a shelf life of 6 months when stored in the original containers in a cool dry place. In more extreme conditions this period might be shortened.

Health & Safety

Uncured flexothane® EPU is toxic and flammable. Ensure the working area is well ventilated during application and drying. Avoid flames in the vicinity Always wear gloves and eye protection when working with the material and avoid excessive inhalation and skin contact. If material is splashed in the eye wash with plenty of clean water and seek immediate medical attention.

Cured flexothane® EPU is inert and harmless.

Important Note

This data sheet is issued as a guide to the use of the product(s) concerned. Whilst a.b.e.® endeavours to ensure that any advice, recommendation, specification or information is accurate and correct, the company cannot accept any liability for application – because a.b.e.® has no direct or continuous control over where and how a.b.e.® products are applied.

Further Information

Where other products are to be used in conjunction with this material, the relevant technical data sheets should be consulted to determine total
requirements.

a.b.e.® has a wealth of technical and practical experience built up over the years in the company’s pursuit of excellence in building and construction
technology.