A guide to non-slip coatings

by jason_cramp | November 5, 2015 3:20 pm

By Brian Field

[1]

Rubber has been used as an anti-slip surface in and around wet areas for much of the past century. It is proven to be a great performer in providing excellent grip and preventing falls, which can turn nasty very quickly on hard, wet surfaces such as pool decks. The problem, however, was rubber always came in the form of a mat or other temporary surfaces and only provided safety in a localized area.

Everyone is familiar with the term ‘necessity is the mother of invention,’ and what was necessary in the pool environment was the need for a non-slip seamless surface, which could be easily adapted and customized to fit any area.

Cue the poured-in-place rubber surfacing market. In a trial back in 1983, granules of rubber were mixed with a high-tech polymerized resin and trowelled over the surface of a pool deck in Garland, Tex. Since then, rubber surfacing has become a popular and efficient way to cover existing decks. In some cases, it is specified on many new construction projects—commercial and residential.

Lay some rubber

[2]

With applications ranging from low-use residential backyard pools to the extreme durability requirements of a major theme park, the composition of the rubber and binder is critical to achieving long lasting success. For someone in the market for a rubber surfacing installation, they will likely encounter a number of different options before making a final decision for what works best for their project. The first selection, however, is the type of rubber to use.

Many different types of rubber can be used for surfacing, all of which are synthetic polymers. Rubber surfacing does not use any natural rubber, which also means it is latex free. Synthetic rubber is cheaper and easier to produce than natural rubber; therefore, with many applications already in use in the automobile industry, it was an easy decision when it came to the materials used on that first pool deck in Texas. That said, there are many different types of synthetic rubber to choose from. The following is a look at which type of synthetic rubber should be used for different applications.

Styrene-butadiene rubber (SBR)

The most common and cheapest type of synthetic rubber available is called Styrene-butadiene rubber (SBR). The basic elements that make up SBR—styrene and butadiene—are byproducts from the petroleum industry. Most commonly used by tire manufacturers, SBR can also be found in shoe soles, hoses, and other applications requiring a cheaper durable rubber.

In the rubber surfacing business, SBR has a wide variety of applications. Almost all of the SBR used comes from the recycled-tire market. This also means it is almost always black. In playgrounds, SBR is the key element in providing the shock absorption layer. It can also be used as a topcoat for a playground surface and running tracks. To achieve different colours when using SBR, it is typically painted with
an acrylic coating or by using a tinted binder. Painting the SBR granules is a less expensive way to achieve a colourful poured-in-place rubber safety surface; however, it does have some drawbacks.

For instance, the colour will wear away, depending on the amount of use the surface gets, revealing the black granule. This creates the need for periodic re-coating of the surface, which can quickly offset the initial cost savings, not to mention the inconvenience of the shutdown periods.

Typically, an SBR surface will be recoated every two to three years. If installed properly and maintained, an SBR surface will last a long time, but it might be worth considering other options.

Ethylene propylene diene monomer (EPDM)

[3]

Most of the bright, vibrant, colourful rubber surfaces found on today’s new playgrounds have been created using another type of synthetic rubber called ethylene propylene diene monomer (EPDM). This material was created to satisfy the need for a synthetic rubber that can withstand the harsh conditions of the outdoors.

It is designed not to crack and has outstanding heat, ozone, and weather resistance. Thermal properties maintain its flexibility between -50 and 150 C (-58 and 302 F). It also has excellent electrical insulating properties and good resistance to many chemicals. Because of these properties, EPDM has been used for decades in seals, gaskets, hoses, waterproofing membranes, and many other applications—all which require extreme durability under the harshest conditions.

The use of high quality EPDM in rubber surfacing is a large factor to its success over the past 32 years. Unlike recycled SBR rubber, EPDM is coloured at the manufacturing stage where the pigment is effectively infused throughout the granule. This means there is no paint or tint to wear away.

The finished surface can be sanded or cut and it would be the same colour throughout. The use of EPDM has enabled rubber surfacing to offer virtually unlimited design potential. The long history of EPDM already used in rubber surfacing combined with decades of history in many other industries is why EPDM is still regarded as the premium choice material.

Thermoplastic vulcanizate (TPV)

Another type of synthetic rubber that has made its way to the rubber surfacing market is called thermoplastic vulcanizate (TPV). The attraction of TPV is its ability to maintain bright bold colours, especially useful in large-scale commercial applications. TPV is relatively new as a surfacing material and to date does not have a long history to fall back on like EPDM does. Time will tell as to whether it can prove itself as a long-term contender before being classified as a mainstream product in the rubber safety surfacing market.

In a bind

[4]

Having discussed the various synthetic rubbers used in a poured-in-place safety surface, it is also important to review the different resins used to bind the rubber granules together. First and foremost, it is essential that any resin used in a wet deck area, whether for a pool or splash pad, be formulated for underwater applications.

Methylene diphenyl diisocyanate (MDI)

The most commonly used binder is methylene diphenyl diisocyanate (MDI). It is an aromatic, one-part, moisture-cured urethane resin, which is not only strong, but also has the ability to keep the rubber granules flexible. It should be pointed out that MDI-bound rubbers will experience a chemical reaction known as ambering, which affects the top granules of the surface. This reaction is noticeable in some colours more than others and will eventually wear off after continued exposure to the elements. Depending on location, or how much sun or shade the surface is exposed to, colour selections should be chosen carefully.

Aliphatic

If an environment is likely to cause surface ambering where very light colours (e.g. white, light grey, or beige) are required in the mix, it may be favourable to avoid this possible reaction by using aliphatic resin, which is not affected by ultraviolet (UV) light. It is more expensive than MDI, but at times when price is not the important factor it can be worth the consideration.

Epoxy resin

Epoxy resin is usually a two-part mix system and careful attention has to be paid to the mixing ratio. Formulations containing powdered metal and rubber or plasticizers are very tough and shock-resistant, which results in a harder finished surface than when using MDI or aliphatic resins. Epoxy can also trigger long-term sensitivity (allergies) from overexposure, and is often expensive.

Weather permitting

[5]

Depending on the weather conditions during the time of installation, it can impact the drying time of any resin. Therefore, it is important to verify the temperature before and during the installation to ensure proper set-up. The outside temperature needs to be consistently above 5 C (41 F) for proper installation. Failure to install the rubber safety surface within the temperature parameters could result in sub-standard quality of the surface or even delamination.

Another important consideration to keep in mind is the resin’s off-gassing of carbon dioxide (CO₂) as it dries. This gas is removed by evaporation through the material when first installed and generally causes no concern; however, inclement weather or improperly mixed materials can inadvertently create blowback, which takes on the form of milky resin sitting on top of the surface. An experienced installer working in the right conditions will rarely need to deal with this, but if necessary, the affected areas can be cut back and reapplied.

Experience is the best teacher

Although the choice of material remains critical to the success and longevity of any rubber surfacing project, equal weight must be given to the installation techniques and experience of those who carry out the project. That said, the right product in the hands of a well-trained contractor will produce a safe, resilient rubber surface that can be enjoyed for decades.

[6]Brian Field is president of Rubaroc Canada and Rubaroc USA, a Canadian-based developer and installer of rubberized safety surfacing. He now operates both offices from Texas. With more than 30 years’ experience, Rubaroc is offered coast to coast through an extensive dealer network. Field can be reached via e-mail at brianf@rubaroc.com[7].

Source URL: https://www.poolspamarketing.com/trade/a-guide-to-non-slip-coatings/

---