In this final post I am exploring the reasons why sometimes there are problems with the actual resin system that may lead to bubble formation. Although this problem is not very common it is growing in importance as many low-cost manufacturers are appearing out of nowhere selling low-priced epoxy products in an attempt to get market share..
It is important to understand that a properly formulated product does not just contain a resin and a hardener. In fact it is made up of a range of important ingredients that make up the system. Properly formulated resin systems contain special additives like defoamers, dispersing agents, and viscosity modifiers. Without these additives the epoxy systems on the market would produce entirely different (and inferior) results. Obviously, all these additives cost money and end up increasing the production cost of the material. Some low-cost producers do not use these additives or limit their composition in order to keep costs down.
Additionally, depending on the product in question, certain de-gassing procedures need to be applied during the manufacturing process in order to remove any air trapped within the product. It is also not uncommon for some formulators to ‘drown’ the system in solvents in order to bring down the cost. What happens then is that during the application stage, the solvent starts to evaporate which inevitably leads to bubble formation as well as shrinkage of the material.
My final word of advice is don’t just pick a product because of low cost. Low cost is usually associated with products of poorer quality. It is preferable to spend that extra money per square metre to ensure a well executed project and a pleased customer.