How to choose the right resin

Polyurethane or epoxy resin? Choosing the right resin when you have something to do is often problematic. Depending on the work to be done, the resin to be used is not the same. What’s more, the number of different resins on the market doesn’t necessarily help you make the right decision. In this article, we’ll look at two main types of resin that are important to distinguish. Epoxy resins (EPO) and polyurethane resins (PU). RESIMARMO uses these two types of resin for different and very specific purposes. However, these two resins have one thing in common. They are almost always composed exclusively of a resin base and a chemical catalyst.

Do you always ?

No, except in the case of a single-component ready-to-use resin.

But what is a catalyst ?

In chemistry, a catalyst is a substance that increases the speed of a chemical reaction. The resulting chemical reaction makes the base resin harder, more stable and more neutral.
Precisely dosed with natural marble aggregate, the resin produces a paste that can be used to create floor coverings. With no unsightly joints, the surface is supple, non-slip and provides excellent drainage. The different shades of marble used offer a wide range of colour effects. Geometric graphics, stripes and colour changes can all be incorporated into the same surface.

EPOXY RESINS

Epoxy resins are the result of polymerising epoxy monomers with a cross-linking agent called a hardener. Its main component is bisphenol A, which can sometimes be combined with bisphenol F to obtain greater resistance. The most commonly used hardener is a cycloaliphatic amine. These are known as polyepoxides or, more commonly, « epoxies ». These epoxy polymers have the EP designation according to the ISO 1043 – plastic and ISO 1629 – rubber standards. Araldite » adhesive is certainly the best-known epoxy polymer. It was first synthesised in the 1940s.

These resins are not used for the manufacture of parts, their rapid setting being the main reason for this. They are most often used for glass fibre lamination or with fillers.

The filler :
Fillers consist of neutral elements and do not alter the quality of the resin. Castability may be affected by an increase in viscosity.
Different types of filler : :

• Aluminium powder or other metals.
  
• Or fibreglass powder or similar..
• Minerals such as talc, limestone, marble, etc..

They can be used as an undercoat for mineral aggregate mixes. They also work wonders as a primer. We use these characteristics to interpose it between the concrete and the RESIMARMO mix.

Main uses

They are used in various economic sectors.

• Decoration : furniture customisation, exterior decoration, marble granulate flooring, etc.
  Electricity : electrical installations such as transformers, turbines and switches, as well as in wind turbines.
• Electronics : production of printed circuits, often combined with glass fibre fabric, as well as encapsulation and cladding of electronic components.
• Food industry : drinks cans, as well as tins and storage tanks. All these containers can be coated on the inside with polyepoxide.
• Construction : Certain floor coverings.
• Transport : Certain car body parts, or even a complete body for competition prototypes.

Advantages

• Low cost.

Disadvantages

• Not resistant to UV rays and therefore age very poorly.
• They turn yellow over time, so their natural transparency should never be visible. They are also used with colour pigments.
• They cannot be used on unstable surfaces such as wood, steel, mortar, etc.
• They become brittle over time.

Risks of using epoxy resin :

Epoxy resin is more allergenic and more insidious. It doesn’t contain styrene, which has that characteristic heady scent – yes, like perfume, but you get bored of it quicker all the same !

Epoxy is dangerous in two ways :

Contact and fumes

Contact: with the skin should be avoided, avoided and avoided, as epoxy is a highly allergenic product. There are two types of risk :

Contact allergy, which results in red patches on the skin, eczema, itching, localised at the point of contact or which can spread well beyond the point of contact and affect the whole body.

Emanations : that we inhale do not cause any real allergies as far as we know. But they do act over time, and in a more perfidious and dangerous way for health. They have a cellular toxicity, particularly on the nervous system. They also have a slower but definite effect on the risk of cancer. Wherever they go when you breathe them (mouth, bronchi, lungs, but also bladder, kidneys, when you urinate what you have inhaled, brain). Like all petrochemical products (paint, for example).

POLYURETHANE RESIN

Polyurethane resin is an organic molecule. It is more flexible than epoxy resin and offers good resistance to impact and temperature variations. It is a urethane polymer. Urethane, or more commonly « carbamate », is any compound produced by the reaction of an isocyanate and an alcohol. Depending on their structure, organic isocyanates are classified into aliphatic, alicyclic and aromatic series. The latter are more rigid and reactive than the former.

This reaction had been known for several decades when, in 1937, Otto Bayer discovered how to make a usable plastic free of polyisocyanate and polyol. Urethane technologies were brought to the United States in 1953 by Jean-Pierre Abbat and Fritz Hartmann. In the 1970s, the use of urethane for wheels, for example, revolutionised roller sports (roller skates, skateboards). It is also found in some toys.

Polyurethanes can be made to a wide variety of textures and hardnesses by varying the monomers used and adding other substances. They are used in adhesives, paints, resins, elastomers (« rubbers »), foams and fibres. These versatile plastics are used in a wide range of industries. Polyurethane resin is also known as « composite concrete ». It has all the main characteristics of concrete, such as excellent firmness, impact resistance and adaptability to the space to be fitted out. Like other concretes, it can be coated with resin, wax or oil.

Main uses

According to a study by ADEME, polyurethanes are used worldwide as follows :

• 34% Flexible block foams.
• 12% Moulded flexible foams.
• 18% Rigid foams for building insulation.
• 8% Rigid foams for household appliance insulation.
• 28% Other
  • Adhesives.
  • Elastomers.
  • Waterproofing.
• Polyurethane’s elasticity, moisture resistance and buoyancy properties make it a popular material in the marine industry. For example, some surfboards and sailboards are built around a polyurethane core. The bladders of kites used for kitesurfing are also made of polyurethane. Similarly, boat hulls are often made from polyurethane foam integrated into a double skin of fibreglass.
• Many types of condom are made from polyurethane. They have the advantage of being less allergenic than latex, while offering excellent quality.
  
• Polyurethane films are used to protect many types of equipment (aircraft wings, trains, cars, wind turbine blades, etc.) from abrasion and erosion.
• Polyurethanes are used in the manufacture of adhesives, particularly for assembling wood or gluing shoe soles. The main advantage of this type of glue is its resistance to water.
• They are widely used in coatings, lacquers, paints and varnishes in the construction, furniture, car manufacturing and wood protection industries.
  

Advantages

• Polyurethane resin is a more flexible resin than epoxy, making it more versatile than epoxy.
• Mixed with marble granules, it produces a seamless, comfortable and hard-wearing floor.
  Its main advantage is that it offers a more flexible floor, while remaining hard thanks to the resin. It can therefore be used for both industrial floors and sports fields, thanks to its resistance to impact and the cracks caused by the passage of time.
• Its main advantage is that it offers a more flexible floor, while remaining hard thanks to the resin. It can therefore be used for both industrial floors and sports fields, thanks to its resistance to impact and the cracks caused by the passage of time.
• This resin makes it possible to really furnish an interior. It is highly elastic and adapts to all room shapes. It can therefore be used to create original shapes throughout the house.
• It’s light enough to be installed upstairs. So don’t hesitate, even if the name « concrete » might put you off.
• What’s more, polyurethane resin can be any colour you like. You can buy one already tinted in the resin itself. Or you can apply a tint to the surface, which can be gloss, satin or matt. It’s up to you to decide which type of floor suits you best, and matches the rest of the house to optimum effect.
• PU resins are extremely easy to mould and reproduce. They are easy to install, even with limited resources.
  

Disadvantages

Although PU resins have good resistance to temperature variations, they do not appreciate sudden changes in temperature. It cannot therefore be installed on underfloor heating.