陶氏水性环氧涂料

Viscosity profile of epoxy dispersion
10 9
8
7
XZ 92533.00 up
6
XZ 92533.00 down
5
4
XZ 92533.00 Good shear thinning properties allowing good flow and spray properties
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 dispersion based on Grade Epoxy Equivalent Weight (gr/eq) Solid content Viscosity @ 23 °C Brookfield, mPa•s Typical average Particle size D[4.3] Liquid Epoxy Resin XZ 92598.00 194 – 204 60 - 75 % 3000 - 30.000 0.5 µ m Solid Epoxy Resin XZ 92533.00 475 – 500 46 - 48 % 3000 - 9000 0.5 µ m Epoxy Novolac Resin XZ 92546.00 184 – 204 56 - 59 % 5000 - 10.000 0.5 µ m
0.80
2
Vmean particle size (microns)
0.75 0.70 0.65 0.60 0.55 0.50 0.45 0.40 0.35 0.30 0 500 1000
R = 0.9262
Particle size can be influenced by the total flow rate
– – – – High solids coatings Powder coatings Radiation cured coatings Waterborne coatings
Toine Dinnissen / March 28th 2007
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NEO Chemical Seminar 2007
Particle size distribution of an aqueous dispersion of an epoxy novolac resin
Particle Size Distribution
14
Particle size distribution of an aqueous dispersion of a solid epoxy resin
Weeks of storage 0 27 56 Average particle size D[4.3] 0.385 µ m 0.385 µ m 0.390 µ m Epoxy Equivalent Weight 190 g/eq 191 g/eq 191 g/eq Brookfield viscosity at 23°C 4660 mPa•s 4200 mPa•s 4200 mPa•s
NEO Chemical Seminar 2007
VOC-free Waterborne
Epoxy Emulsions and Dispersions for Ambient Cure Coatings
Toine Dinnissen / March 28th 2007
Page 1
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
Only very light sediment after one year of storage at 23°C which can be easily stirred in
Toine Dinnissen / March 28th 2007 Page 7
NEO Chemical Seminar 2007
Pa*s
3
2
1
0 0.1 1 10 s-1 100 1000
Solid contents up to 54% without solvents can be achieved if high viscosities can be tolerated
Toine Dinnissen / March 28th 2007
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 • 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)
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NEO Chemical Seminar 2007
Mechanical dispersion Process
百度文库
Process patented by Dow:
Continuous feed of resin and water to the mixing unit under high shear High viscous resins can be dispersed without the addition of solvents Excellent transfer of process parameters from lab to pilot to manufacturing scale Submicron and mono modular particle size distributions
1500 2000 2500
Flow rate, g/min
Toine Dinnissen / March 28th 2007
Page 10
NEO Chemical Seminar 2007
Influence of process parameters
Viscosity versus particle size for WB Epoxy Novolac dispersion samples Viscosity measured by Brookfield DV-1 with Spindle #3 at 5 rpm, 23 ?C
Toine Dinnissen / March 28th 2007
12
Volume (%)
10 8 6 4 2 0 0.01 0.1 1 10 Particle Size (µ m) 100 1000 10000
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NEO Chemical Seminar 2007
Storage Stability
Toine Dinnissen / March 28th 2007 Page 2
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 • 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
Toine Dinnissen / March 28th 2007
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NEO Chemical Seminar 2007
Typical Particle Size distributions
Particle Size Distribution
16 14
Volume (%)
12 10 8 6 4 2 0 0.01 0.1 1 10 Particle Size (µ m) 100 1000 10000
Submicron particle size distributions lead to excellent storage stabilities demonstrated with the example of a WB epoxy novolac dispersion XZ 92546.00
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 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
Toine Dinnissen / March 28th 2007
Page 9
NEO Chemical Seminar 2007
Influence of process parameters
Influence of flow rates on average particle size of WB Epoxy Novolac Dispersion