Syncoat is our range of resin coating and flooring systems. Over time there have been many types of resin technology and some are better than others for different purposes. Sometimes a blended system is the right choice. It is never a case of “this is the best resin in the world for everything”, one must understand the attributes of each product and the part they play.
As a brief overview I will outline the different resins and their best application.
Epoxy Resin Systems
Noun – An adhesive, plastic, paint, or other material made from a class of synthetic thermosetting polymers containing epoxide groups.
As with most resins, Epoxy is a 2 component (base and cataylst) liquid, that when mixed undergoes a chemical reaction that causes the resin to set. This is useful for us, as while it is in liquid form we can apply the epoxy to a substrate and then it goes hard and is suitable as a floor surface. Most epoxies form a rigid coating with a tenacious bond to a properly prepared porous surface. Different blends of epoxy resin can be used as a moisture barrier to prevent moisture escaping through concrete floors and walls. We call these Moisture Tolerant or epoxy polymides. Not all epoxies are equal so it is important to get professional advice.
A) Epoxies usually adhere very well to prepared substrates (always grind or abrade the concrete surface).
B) Epoxy can be applied from a thin roll on layer, to a thick 4mm layer if more impact protection is required. (just be prepared to pay a lot more).
C) Epoxy resin is at the lower end of the cost scale.
D) There are Moisture tolerant epoxy coatings that can be applied to new or damp floors (less than 10% are capable of moisture tolerance).
E) There are solvent free epoxies that preform very well without the odour during application.
F) Glossy epoxy floors will show scratches and signs of wear quite quickly (they last a long time, but mar quite easily)
G) Epoxy floors take days to install and then days to cure (7 days before they should get wet)
H) Most epoxy resins will yellow with UV exposure – sunlight or artificial lights.
Summary – Epoxy floors are great for internal areas, not subject to direct sunlight, where a glossy finish and optimum visual appeal is not required. Epoxies make great base coats for systems and the moisture tolerant versions are essential in some circumstances.
Please do not misunderstand me. We do lots of epoxy floors and lots of epoxy base-coat floors (with other resins over the top).
Polyurethanes (sometimes refered to as just Urethanes) are in the class of compounds called reaction polymers, which include epoxies, unsaturated polyesters, and phenolics. In Liquid form Polyurethane has a part A and a part B, polyurethanes are produced by mixing two or more liquid streams. Polyurethane is a common “plastic” use extensively in manufacturing of everything from seats to skateboard wheels. Polyurethane is also commonly used on timber floors. Many tradespeople moving from the timber flooring industry to concrete flooring have continued to use polyurethanes.
One limitation of most forms of polyurethane it it’s inability to wet or penetrate into the surface of concrete. The result is poor adhesion and subsequent bond failure.
This is unfortunate as polyurethane has better abrasion/scratch and chemical resistance than most epoxies, and therefore is a better flooring finish. But if it can’t bond the the surface and peels off in sheets, then it is not the right system.
One way around this is to use an epoxy base coat to guarantee adhesion to the concrete. But this requires careful selection of both the epoxy and the polyurethane to ensure they will crosslink and care taken that they are applied at the right curing stage of the epoxy. Too early and you have reaction, too late and you have rejection.
Like epoxies, most urethanes will discolour or yellow with UV exposure and are not suitable for external application or near windows.
Excellent chemical resistance
Very good scratch and abrasion resistance
High heat resistance (the thicker the coating the higher the resistance)
Poor adhesion directly to concrete
most will yellow with UV exposure
Polyurea is a type of elastomer that is derived from the reaction product of an isocyanate component and a synthetic resin blend component through step-growth polymerization. The word polyurea is derived from the Greek words πολυ- – poly- meaning “many”; and ουρίας – oûron meaning “to urinate”. The latter term refers to the substance urea, found in urine, rather than urine itself. (thanks wikipedia)
Their fast reactivity and relative insensitivity to moisture make them useful coatings for large surface area projects, such as secondary containment, manhole and tunnel coatings, tank liners, and truck bed liners. Excellent adhesion to concrete and steel is obtained with the proper primer and surface treatment. They can also be used for spray molding and armor. Some polyureas reach strengths of 6000psi (40MPa) tensile and over 500% elongation making it a tough coating. The quick cure time allows many coats to be built up quickly. Some formulations can cure in a couple of seconds.
In terms of floor coatings, the cure time can be altered to suit the application. One difference between polyurea and epoxies and urethanes is that epoxies and polyurethanes cure faster in concentration (in the mixing pot) and more slowly once spread out. Polyurea cures faster once spread out. This is an advantage for floors that require quicker return to use or the next coat to be applied.
Some formulations of polyurea resin allow a floor to be completed in one day and returned to use after 4-6 hours. This is good news for business owners who can not justify being closed for days.