How Is Epoxy made?

Lately, a lot of people wondering what is the best type of flooring for their house, garage or commercial place. In addition to the usual options like hardwood flooring, more and more people are choosing epoxy flooring or Vinyl flooring for their new house or remodeling project. 

Today I’ll explain about epoxy and the formation of it. 

What is Epoxy?

Epoxy is an amalgamation of organic compounds. It is manufactured using chains of carbon which are linked together to the elements like hydrogen, oxygen or nitrogen. The connection is formed using a covalent bond in which elements pair with each other and share electrons to stay with each other.

The term ‘epoxy’ is a comprehensive terminology. It helps to describe the epoxide functional group, which forms with a chain of oxygen and carbon atoms. The functional group determine the primary characteristics of the molecule formed during a chemical reaction. However, it means that molecules consisting of epoxide functions can react chemically to create a solid yet highly malleable material.

The term epoxy is also used to denote epoxy resins. Epoxy resins are known as polyepoxides. It is a group of reactive prepolymers and polymers that eventually forms epoxide groups. They are a result of a chemical reaction called ‘curing’. The process in which a material becomes hard after they are exposed to heat, air or chemical additives is called curing. It occurs with the help of a catalyst in epoxy.

The formation of Epoxy

The commercially used epoxy polymers are manufactured when a compound reacts with acidic hydroxyl groups and epichlorohydrin:

All the epoxy resins produced with the help of epoxy monomers are called glycidyl-based epoxy resins. The hydroxy group can be procured from aliphatic diols, polyols ( also known as polyether polyols), phenolic compounds or dicarboxylic acids.

Bisphenol-based epoxy resin

The epoxy resins which are used worldwide is 75% based on bisphenol A. This is a two-staged reaction in which epichlorohydrin is first added to bisphenol A, then in a condensation reaction, a bisepoxide is formed with a stoichiometric amount of sodium hydroxide. Then chlorine atom is released as sodium chloride, and the hydrogen atom is released in the form of water.

Novolac epoxy resin

When phenol reacts with methanal Novolaks are produced.  Then with the help of glycidyl residues, The reaction of epichlorohydrin and novolaks produces novolaks such as Epoxy Phenol Novolac (EPN) or epoxy cresol Novolak (ECN). These are highly clinging to solid resins typically carry 2 to 6 epoxy groups per molecule. By curing, highly crosslinked polymers with chemical resistance and high temperature are formed due to the high functionality of these resins.

The reaction of phenols with formaldehyde and subsequent glycosylation with epichlorohydrin produces epoxidized novolak, such as Epoxy Phenol Novolak (EPN) and Epoxy Cresol Novolak (ECN). These are highly adherent to solid resins with typical mean epoxide functionality of around 2 to 6. These resins are high in epoxide functionality and result in the formation of a highly crosslinked polymer network.

 Aliphatic epoxy resins

Basically, there are two types of Aliphatic epoxy resins. First one is obtained epoxidation of cycloaliphatic epoxides and epoxidized vegetable oils which creates a double bond. The other one is formed when glycidyl ethers react with esters and epichlorohydrin is formed. Cycloaliphatic epoxides consist of one or more aliphatic rings in the molecule which contains oxirane ring.

Epoxidized vegetable oils are formed by the process of epoxidation of the unsaturated fatty acids when it reacts with peracids. In this case, the peracids formed in situ by reacting carboxylic acids with hydrogen peroxide. 

Halogenated epoxy resins

Halogenated epoxy resins are generally commixed for obtaining special properties. For achieving flame retardant properties, Brominated bisphenol A is used,   like in electrical applications. The tetrabrominatedbisphenolA(TBBPA, 2,2-bis (3,5-dibromophenyl, propane) or its diglycidyl ether, 2,2-bis [3,5-dibromo-4-(2,3-epoxy propoxy) phenyl]propane, can be added to the epoxy formulation. The investigation of Fluorinated epoxy resins is for some high-performance applications, such as the fluorinated diglycidether 5-heptafluoropropyl-1,3-bis [2-(2,3-epoxypropoxy) hexafluoro-2-propyl] benzene. It behaves as a wetting agent (surfactant) for contact with glass fibres because it has low surface tension. Because of its reaction to hardeners in comparison to bisphenol A. The epoxy resin then leads to a high chemical resistance and low water absorption thermosetting plastic when it is cured. However, the business use of fluorinated epoxy resins is limited by its restricted cost.

Epoxy can be used as adhesives, paints, coatings and composite materials. It is used as tools in industries for producing moulds, master models, laminates, castings, fixtures, and other industrial production aids. Epoxy resin formulation plays an essential part in the electronics industry, and are employed in motors, transformers, generators, bushings, switchgear,  insulators, printed wiring boards (PWB), and semiconductor encapsulants. 

Nick Shushan is the owner of 2 flooring businesses in NY, he owns Parqet Ave which is a hardwood flooring in Queens NY and NYC Epoxy Flooring epoxy flooring company that serves all boroughs in NY.