Additives can be an enabler of epoxy coatings in various industries and applications like industrial applications like concrete flooring, handles, screw drivers, adhesives and many more.
See how different additives can bring value to epoxy coating, take the quiz now.
What are the key advantages of using epoxy coatings?
Which of the following are not appropriate applications for epoxy coatings?
How could you address a foam problem in an epoxy coating?
What additivies could you use to incorporate pigments for asthetics / protective effects?
How can settling problems be addressed in an epoxy coating?
What can be used to address film defects and substrate wetting?
How can an epoxy coating be softened?
A Fast curing or short cure times
B UV resistance
C Chemical and water resistance, durability
D Soft feel
Epoxy coatings are known and used for their excellent overall chemical and water resistance, as well as durability.
Epoxies are known for their chemical and water resistance as well as durability. They also degrade with UV exposure (e.g., sunlight), leading to discoloration, flaking, and potential cracking which will compromise the protection of the substrate beneath. UV absorbers and light stabilizers can be added to the formulation to enable use in exterior applications.
A Indoor flooring
B External surfaces exposed to sun light
C Kitchen countertops
D Screwdriver handles
Epoxies are known to degrade with UV exposure (e.g., sunlight), leading to discoloration, flaking, and potential cracking which will compromise the protection of the substrate beneath. So it is not generally recommended to use epoxies as top coats for external applications where sunlight or UV exposure is likely. UV absorbers and light stabilizers can be added to the formulation to enable use in exterior applications.
Epoxy chemistry is extremely versatile including indoor flooring, kitchen countertops and even to form screwdriver handles. Epoxies are, however, susceptible to UV degradation and are not recommended for external sun exposure type applications. UV absorbers and light stabilizers can be added to the formulation to enable use in exterior applications.
C More Resin
Defoamers are additives designed to prevent and destroy foam as it forms in a formulation. They are the ideal way to do the job.
Adding more solvent may reduce the viscosity and allow gas bubbles to migrate out of the formulation more freely, but they typically increase the VOC of the coating which is not desirable. Defoamers are the most efficient tool for the job. Adding more resin does not effectively reduce foam.
A Rheology Modifier
A dispersant wets the pigment surface and prevents the pigment particles from agglomerating, which enables the best color and rheology in a formulation.
While rheology modifiers can help with settling, sag, and flow, they have no contribution towards aiding the dispersion of pigments. Dispersants are the proper tool to use. For 100% solids epoxy formulations, water would not likely be compatible and would disrupt the formulation.
C Rheology Modifier
A low shear rheology modifier is ideal for addressing the settling of pigments. With the right rheology modifier, a shear thinning behavior is achieved to allow for ease of application.
While dispersants can minimize the interaction of pigments in a coating, they cannot fully address settling of pigments in all cases. For such cases, the best overall solution is to use a rheology modifier. A plasticizer will soften and enable a formulation to flow more easily, but will not effectively control settling. A rheology modifier is the proper tool to use.
A Wetting Agents
B More Epoxy Resin
C Add Solvent
Wetting agents lower the surface tension of the formula to overcome issues with application of the coating (wetting) on substrates and will also address surface contaminants on the substrate that can lead to craters. Some wetting agents even have an antifoam feature to them.
Adding solvent may improve the wetting behavior of the formulation on a substrate, but it will also increase the VOC significantly. A wetting agent is the most effective way to address this issue. Adding more epoxy resin will not effectively change the surface tension to enable substrate wetting.
A Lower solids
B Add Solvent
A plasticizer adds a lubricating effect to the formulation which will enable a softer, more flexible film while maintaining good mechanical and chemical properties.
Lowering the solids of the coating may have detrimental effect on mechanical and aesthetic properties of the coating, not to mention potential negative impact on VOC. A plasticizer is a good way to achieve a softer or more flexible coating while still having good mechanical and chemical properties. Adding solvent will lover the viscosity of the formulation, but will not yield a softer, more flexible coating after curing. A plasticizer is a good way to achieve this goal.