E-Sperse® Products for Epoxy Coatings – Waterborne and Solventborne
E-Sperse® Waterborne Epoxy Additives
E-Sperse® epoxy additives provide long pot life and short cure times to waterborne epoxy emulsions. They greatly increase the stability of epoxy resin emulsions and compatibilize hardeners and epoxies. E-Sperse® surfactants are also miscible in the epoxy resin. E-Sperse® 703 imparts freeze/thaw to aqueous epoxy dispersions.
The unusual stability of these systems is due to the similarity of the surfactant hydrophobe and the epoxy chemical structure providing for stable anchoring of the surfactant to the dispersed epoxy micelle surface. Thus, the waterborne particle stability benefits are similar to those of a reactive surfactant but when drawn down into a coating, the E-Sperse® surfactant will dissolve into the bulk of the curing resin. This will minimize the risk of the formation of surfactant rich domains in the coating, thus improving its water resistance.
Ethox Chemicals new E-Sperse® surfactants for epoxy emulsions:
|E-Sperse® 100||60 - 65||Anionic, sulfate, neutralized|
|E-Sperse® 1711||100||Anionic, sulfate, NH4+ salt|
|E-Sperse® 704||30||Anionic, sulfate, NH4+ salt|
E-Sperse® 704 is an excellent choice to create long-term stable epoxy dispersions without added glycols or solvents creating a VOC- and APE-free system. It also allows for low viscosity high solids systems. Since no reactive epoxy groups are added, recalculation of the EEW is not needed.
E-Sperse® 703 can be added to E-Sperse® 704 to produce epoxy dispersions that are freeze/thaw stable. With this addition the epoxy dispersion maintains its low viscosity including its long-term shelf and heat age stability.
A 75% by weight epoxy dispersion is produced by adding liquid epoxy, water, and between 1 and 5% E-Sperse® 704 into a suitable container. Blends of E-Sperse® 704 and E-Sperse® 703 may also be employed. This mixture is then sheared for about 3 minutes to produce the dispersion. Heating of the epoxy mixture is required to disperse epoxies that are solid at room temperature.
EPOXY HARDENER APPLICATIONS - PERFORMANCE BENEFITS
E-Sperse® 704 and E-Sperse® 703 are excellent choices to extend the pot life of 2K epoxy dispersion systems. The addition of E-Sperse® 704 to amine hardeners improves the stability of the mixed epoxy and hardener allowing for better uniformity of the coating. It also increases the pot life of the system while only slightly affecting cure time. This allows the applicator increased working time and less wasted material while not sacrificing productivity due to slow curing.
Incorporation of these surfactants into the waterborne epoxy system will likely result in significant improvements in corrosion and blister resistance for epoxy coatings.
Simply blend E-Sperse® 704 into your existing hardener package. Typical suggested starting point levels are between 10% and 50% of the hardener on solids. An increase of 100% in pot life was obtained when E-Sperse® 704 was added to an aliphatic amine hardener and an epoxy dispersion (produced with 5% E-Sperse® 704). It is suggested that the formulator optimize the addition for the appropriate end use needs.
Solventborne Epoxy Systems
The addition of ERS 480 to solventborne epoxies results in higher elongation in the coatings as well as improved impact resistance. However, depending on the amount used and the ethoxylate chain length, it may have a detrimental effect on corrosion protection.
- “Improved Epoxy Dispersions” Charles F. (Chip) Palmer, in Proceedings of the Waterborne Symposium 2013, J W Rawlins, R Storey, editors.
- “Surfactant System for Waterborne Epoxy Coatings Simultaneously Giving Long Pot Life, Short Cure Times, and Freeze/Thaw Stability,” Charles F. (Chip) Palmer Eastern Coatings Show, May 2013.
- The information contained herein is believed to be correct; however, it should not be construed as a guarantee or as a statement of suitability for use in any application. This information should not be considered as a recommendation to violate any patent.
EthoFlex® ER Additive for Solventborne Epoxy
EthoFlex® ER is an additive for epoxy coatings. With this single additive a number of epoxy coating properties are improved. These include toughness, impact resistance, corrosion resistance, gloss, weathering resistance, and adhesion. Not only does no other additive do all of these things without hurting pot life or cure time, or increasing VOCs, the performance of EthoFlex® ER exceeds the performance of most other single-property additives in their designed use. Usage is 5-30% depending on the quality of the starting epoxy resin and hardener.
Added to Epoxy or Hardener
Used with any solvent