Frequently Asked Questions
Concrete is a mixture of cement, aggregates and water, which when mixed together at a typical w/c ratio, cement hydration takes place forming C-S-H bonds. For ease of working, excess water is always added to the cement mixture and once the concrete slab is poured and cured; it needs 28 days for the excess moisture to come out of the system. It reaches a point of equilibrium once the concrete is cured for 28 days and the moisture retained within the concrete at this point of equilibrium is called residual moisture. The residual moisture should be below 5% for any resinous flooring to be laid.
Abrasion resistance can be defined as the ability of a material to resist to withstand mechanical action such as rubbing, scraping or erosion. It is a very important performance parameter for industrial floorings. Taber abrasion tester is used to determine a flooring’s resistance to abrasion by weight loss method conforming to ASTM D 4060. The test specimen after weighing the original weight, is placed on the Taber abrasion tester. 1000 gram load is placed on top of the abrader wheel and allowed to spin for 1000 revolutions. C-17 or H 22 abrading wheels are specified. The final weight is taken after 1000 cycles and loss in weight shows the abrasion resistance of the floorings. A typical epoxy flooring shows a weight loss of 80-100 mg (CS17 wheel), while polyurethane coatings shows a weight loss of 40-60 mg, which means PU is more abrasion resistant than epoxy.
Among epoxy primers, Cipy offers Cipoxy 11, 15, 16, 17 and Aquoxy 50. The following table shows their characteristics.
Solvent free/solvent borne/aqueous
Polymer: Filler ratio
Moisture insensitive primer. Compatible with PU & PU-Concrete topcoats
Moisture insensitive. Compatible with epoxy, PU & PU-concrete topcoats
Primer for PU-Concrete and Cipocem 3K
The moisture which emanates continuously from the concrete even after 28 day cure is called rising moisture, which creates mayhem with industrial floorings, leading to osmotic blisters. This happens when there is no damp proof membrane (DPM) between PCC and RCC or when the concrete is cast at a place where the water table is very high. Moisture from the ground makes its way into concrete floor, traverses through the capillaries. These moisture vapour transmission (MVT) forces exceed the adhesive strength of the flooring, creating blisters, delamination and ruptures.
EPU is a short abbreviation for hybrid polymer of epoxy and polyurethane. EP stands for epoxy and U for Urethane. It is also called as urethane modified epoxy. Cipy was the first to introduce the first EPU flooring in the country, by infusing urethane groups into epoxy polymer matrices where the functional properties of epoxy (adhesion, toughness and gloss) are combined with those of PU (abrasion resistance, flexibility and impact resistance). EPU flooring systems are more flexible, more impact and wear resistant than their epoxy counterparts. They are characterised by excellent flow, self-smoothing feature, resilience, and good abrasion resistance.
ECC is a short abbreviation for Epoxy Cement Concrete. EMC is Epoxy Modified Concrete. ECC is a three component underlay consisting of a modified epoxy resin, a specially formulated waterborne amine and a powder pack containing cement, graded aggregates and plasticisers, thereby forming a dual reaction: Epoxy is cured by amine, while the water in the waterborne amine hydrates with cement to form concrete.
ECC (Cipocem 3K) is used as a residual moisture mitigation system and can be applied as underlay on damp concrete without causing blisters. This is used as a self-smoothing underlay, at a thickness between 2-4 mm. A polymeric overlay, either epoxy or PU, can be laid over Cipocem 3K, after 24 hours of curing.
Epoxy flooring is a 2K system, consisting of epoxy resin and a curing agent. Epoxy resin is a reaction product of Bisphenol A and Epichlorohydin. The curing agent is amine or amide, which reacts with epoxy resin to form a tough, hard, glossy polymer. Epoxy is a rigid polymer with a very low flexibility of 1-2%.
PU is a reaction product of isocyanates and hydroxyl groups to form polyurethane linkages. There are two types of polyurethanes: Aromatic and Aliphatics. Aromatic Polyurethanes are based on aromatic isocyanates like TDI, MDI etc, whereas aliphatic polyurethanes are based on aliphatic and cyclo-aliphatic isocyanates like IPDI, HDI, TMXDI etc. Aromatic polyurethanes turn yellowish on exposure to sunlight, while aliphatic polyurethanes are recommended for outdoor applications because of their light stability. PU is characterized by its excellent abrasion resistance, flexibility and impact resistance.
MMA floorings offer stupendous advantages over other seamless flooring systems like epoxy and PU. A typical MMA floor will set within 1 hour, while 6 to 24 hours are normally required for the common fluid applied floor coating systems for the curing process. The rapid cure characteristics of MMA enables the installation to be concluded on a fast track, reducing downtime and execution cost. MMA resin cures via a radical polymerization reaction, catalysed by 50% granular benzoyl peroxide. A Cipy MMA flooring system which consists of primer, screed and topcoat cures rapidly @ 30-40 minutes per individual layer and the whole three coat system can be installed in 1.5-2 hours and returned to service within 4-5 hours.
The three main parameters needed to be considered for choosing the right flooring system for your facilities are abrasion resistance, flexibility, and impact resistance. Abrasion resistance should be higher, with a weight loss of around 40-50 mg. The system should have adequate flexibility to withstand the concrete substrate movements. It should be resilient enough to resist impact of falling objects without cracking.
One of the main parameters needed for the floorings for F&B is thermal shock resistance. A flooring that is thermal shock resistant has the ability to resist rapid and sudden changes in temperature in food and beverage facilities where the vessels and floors are frequently cleaned with steam. All resinous flooring systems crack or delaminate, as they can’t withstand temperature swings, except PU-Concrete floorings. PU-Concrete floorings are based on a hybrid technology combining PU and Cement, triggering two reactions simultaneously:
- Formation of urethane linkages due to NCO-OH reaction
- Formation of concrete(C-S-H) due to cement hydration
PU-Concrete floorings, i.e., Cipy’s Duracrete floorings exhibit similar coefficient of thermal expansion as that of concrete and hence can sustain temperature extremes.
Epoxy resin is a hard polymer and has a very low flexibility of 1-2 %. Epoxy resin is not resilient enough to withstand the cracks that will form in the concrete substrate due to expansion and contraction in summer and winter. That is why you can find cracks in epoxy floorings after a few months of installation. Also, it has comparatively lower wear resistance than EPU & PU.
All Cipy floorings are naturally bacteriostatic and fungistatic, as they have no seams or grout lines to harbour dirt, dust and pathogens. The floors of a hospital and healthcare facility contribute to a large hosting surface area for pathogens which can remain active from days to months and hence there is a necessity for antimicrobial floorings which do not allow the viruses, bacteria and microbes to replicate. The antimicrobial properties can be further strengthened by the addition of a synergistic combination of organic and inorganic antimicrobial agents. Our hygienic floorings like Cipoxy SL 1000 AM, Duracrete MD/AM are the reinforced antimicrobial floorings.
Unlike cementitious terrazzo, epoxy terrazzo is a thin set, high strength terrazzo flooring system, employing a high strength epoxy resin along with decorative aggregates such as marble, granite, recycled glass, and mother of pearl. This can be laid at as thin as 8 mm as against a conventional cementitious terrazzo of 50 mm thickness.
Polyurea is a reaction product of polyisocynate and amine along with amine chain extenders, triggering rapid crosslinking to cure within a few seconds. Polyureas cannot be applied by conventional methods like brushing or rolling, but strictly by high pressure plural spray equipment.
According to PDA, pure polyurea is a reaction product of an isocyanate component and a resin blend component. The isocyanate can be aromatic or aliphatic in nature. The resin blend must be made up of amine-terminated polymer resins, and/or amine terminated chain extenders.
In hybrid polyurea, the resin blend will consist of amine terminated polymers along with hydroxy containing polyols, forming a dual reaction of polyurethane and polyurea. Hybrid polyurea exhibits both the properties of polyurethane and polyurea.