• U.S.: 3 major organizations driving the reduction of VOC – Environmental Protection Agency (EPA, through Clean Air Act) – South Coast Air Quality Management District (SCAQMD) – Ozone Transportation Commission (OTC)
NEO Chemical Seminar 2007
VOC-free Waterborne Epoxy Emulsions and Dispersions
for Ambient Cure Coatings
Toine Dinnissen / March 28th 2007
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NEO Chemical Seminar 2007
– “Green Image” – environmental friendly coatings – Low odor, low flammability – Easy cleaning of equipment with water
Making use of the excellent properties of Epoxy resins (e.g. corrosion resistance, chemical resistance, adhesion,…) with minimal amounts of solvent to fulfill legal and environmental requirements
Grade
Liquid Epoxy Resin XZ 92598.00
Solid Epoxy Resin
XZ 92533.00
Epoxy Novolac Resin XZ 92546.00
Waterborne Epoxy dispersions?
– Stricter legislation is limiting the use of solvents-Volatile Organic Compounds (VOC) in paints e.g.
• European directive 1999/13/EC and amendment 2004/42/EC – first stage implemented in 2007 – second stage implemented in 2010
Dow’s Technology Approach
• Dow technology – Non ionic surfactant was especially developed for WB epoxy resins – Surfactant is epoxy functional so that it will be part of the cured matrix – Unique dispersion process which allows mono modular and submicron particle size distributions – Submicron particle size distributions allow a good storage stability and film formation – Formulator can use solvent of choice – No additional solvent, so low VOC formulations can be prepared
Toine Dinnissen / March 28th 2007
Chemistry +
Process
Properties
Ambient cured coatings
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NEO Chemical Seminar 2007
VOC free WB epoxy dispersions
Aqueous dispssen / March 28th 2007
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NEO Chemical Seminar 2007
Drivers and alternative approaches
• Typical solvent borne formulations for Marine and Protective coatings are based on epoxy resin grades with an Epoxy Equivalent Weight of ~500 gr/eq containing solvents like Xylene
– High solids coatings – Powder coatings – Radiation cured coatings – Waterborne coatings
Toine Dinnissen / March 28th 2007
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NEO Chemical Seminar 2007
• Grades – Emulsion of a Liquid Epoxy Resin – commercial grade – Dispersion of an Epoxy Novolac Resin – commercial grade – Dispersion of a Solid Epoxy Resin – commercial grade
• Typical solvent content of these solid epoxy resin solutions is 25% • Major contributor to the overall VOC content of a solvent borne
formulation • Several approaches exist to minimize or eliminate the VOC content