NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 1 Marine Coatings & Protective Coatings.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 2 Marine & Protective Coatings Main function of epoxy coatings is to protect steel structures against corrosion and against chemicals Marine and Offshore Industrial Steel Structures Industrial Maintenance Tanks Transportation –Railcars –Large vehicles –Sea containers [China]
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 3 Key Market Segments in Europe Worldwide consumption of anticorrosion coatings estimated at ca. 1.1 Millions MT, with a value of ca. $ 5 Billions in M&PC coatings represent 4% of the global coatings volume, but 8-9% of the total value. Source: SRI Consulting
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 4 Marine Coatings Ballast tanks The role of epoxy coatings is to protect against corrosion each part of ships, which are continuously exposed to severe conditions, i.e. sea water immersion, splashes of sea water, UV rays –maintain the value of the assets –ensure vessel safety –protect cargoes, e.g. grain or liquids
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 5 Marine sub-segments –Water ballast tanks –Under water hulls and sides –Cargo tank linings –Cargo holds –Boot-topping and splash zones –Topsides and external superstructures –Offshore oil drilling platforms Key Performances requirements Resistance to corrosion Chemical resistance Mechanical resistance, e.g. abrasion Weatherability
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 6 Oil & GasChemical Processing Power Generation Pulp & Paper Mining & MetalsBridges & Infrastructure Typical Protective Coatings Markets Pictures downloaded from Akzo Nobel Coatings web-site
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 7 Non-generic Competition Source: SRI report 2001 Epoxy Resins are essential raw materials for Marine & Protective Coatings. Epoxy systems offer an outstanding balance between performances [durable corrosion protection] and costs.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 8 Desired Properties of M&PC Coatings Each end-use requires an optimum balance between: –Ambient application window –Ease of applying [ spray, brush, roll ] –Solids content, VOC content –Film thickness –Drying time –Sufficient hardness / flexibility –Edge covering –Impact resistance –Overcoating time window, –Long term corrosion protection –Long term adhesion, adhesion in wet environment e.g. in water immersion conditions –Resistance against chemicals { acids, solvents, caustic,… }
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 9 Chemical cure2 pack systems Limited pot life Excellent adhesion on many substrates Excellent corrosion protection Superior resistance to water, chemicals, solvents & oil Extremely resistant to mechanical stress Good surface preparation required Curing rate depends upon temperature. Chalking when exposed to sun light Over coat-ability limitations Minimum & maximum intervals between layers to be respected Cathodic disbondment resistance required in some applications Properties of ambient cured epoxy coatings
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 10 Main Dow resins employed in M&PC Bisphenol A epoxy resins & solutions –D.E.R. 331 –D.E.R. 337X80 –D.E.R. 660X80 –D.E.R. 671 –D.E.R. 671X75 –D.E.R. 671XB70 Bisphenol F epoxy resin –D.E.R. 354 Epoxy novolac resins –D.E.N. 425 –D.E.N. 431 –D.E.N. 438X80 Trademark of the Dow Chemical Company } Best chemical resistance Trend towards Liquid Epoxy Resins and Semi-Solid Epoxy Resins expected in Europe due to more stringent VOC regulations
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 11 Schematic epoxy coatings formulation 2- Pack Solvent Borne Systems Component AComponent B Epoxy Resin(s)Curing Agent(s)Pigments & Extenders Solvents AdditivesAdditives Accurate Mix ratio. Thorough mix prior to use. Pot-life of hours. (Pot life depends on temperature, quantity, type of resin and hardener) Modifiers e.g. hydrocarbon resins or reactive diluents can be used
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 12 Typical curing agents used in M&PC Curing agents [mostly based on amine chemistry]. Polyamidoamines [Versamide TM type] Amidoamines Epoxy - Amine adducts Mannich bases [Faster cure] Phenalkamines [Low temperature cure] Typical accelerators Tertiary amines e.g. Ancamine TM K54 type Alkyl phenols Remarks: Induction time needed with some curing agents to overcome the limited compatibility with epoxies and to minimize the blushing effect. Curing agents frequently used at under-stoichiometric levels to minimize blushing [typical NH / epoxy stoichiometry = 80%]
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 13 Example of Anticorrosion Coating System Metal Substrate Epoxy Topcoat; 150 µm Epoxy Epoxy, PU, Alkyd, Acrylate ca 400 µm Mid coat; 150 µm Primer; 70 µm Top Coat: Appearance & Protection against UV-light Mid Coat:Barrier Protection effect. Intercoat adhesion Primer:Corrosion protection & Adhesion
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 14 Examples of commercial coatings systems (1) Epoxy zinc primer30 µ Epoxy primer50 µ Epoxy tie coat100 µ Epoxy top coat50 µ or weatherable PUR Epoxy zinc primer30 µ Epoxy aluminium primer300 µ Epoxy top coat300 µ } Steel protection } Superior steel protection, e.g. off shore
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 15 Typical Epoxy Polyamide Primer Formulation. ( Red oxide & Zinc Phosphate) Epoxy resin componentParts by weight D.E.R. 671X75 Epoxy Resin Solution18.7 Pigment grinding additive0.5 Zinc Phosphate10 Silica Powder 5 Iron Oxide Red20 China Clay 5 Fumed silica thickener 1 Xylene17 n-Butanol 7 Curing agent component: Versamide ® 115/70X10.6 Or similar polyamido-polyamine hardener
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 16 Typical Properties of type 1 epoxy resin / polyamide formulation. Pot-life: min 8 hours Coverage: m2 per 100 µm thickness Surface hardness: 300 s Persoz Pendulum Erichsen Flexibility: min 7 mm Salt Spray Test: min 1000 hours Low Temperature Cure: 10 °C Adhesion to all kinds of substrates Note: Properties strongly depend on the surface preparation
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 17 Interdependency between Pot life, Drying Times and VOC Drying times (full dry) hours at low temperature Pot 20°C, hours 1 Hr 8 Hrs High VOC [D.E.R. 671] 48 Hrs24 Hrs16 Hrs Solvent free Low VOC, <250 g / litre Low VOC or VOC free epoxy systems exhibit a poorer balance between drying time and pot life than high VOC systems.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 18 Drying times and pot life - Additional comments The coatings are often stored in a heated warehouse to prevent addition of solvent to adjust the viscosity to spray viscosity. The epoxy – amine reaction is exothermic Increase of the pot temperature after mixing of the 2 components Coatings drying time dominated by the temperature of the substrate and by the degree of ventilation. Faster reaction kinetics in the pot than in applied paint film, especially in winter time. Generally lower viscosity epoxies have a lower EEW (a higher oxirane content) Higher levels of hardener needed or hardeners with higher NH content needed. High solids / solvent free coatings have a higher concentration of reactive groups in the mixed paint, which goes against pot-life.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 19 Surface preparation The removal of rust salt mill scale weld spatter grease & oil dirt old paint depending upon quality and rounding of sharp edges are critical to achieve optimum performances of epoxy coatings Surface preparation is labour intensive and represents a significant part of total costs of the coating process.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 20 Blast cleaningIdeal Hydro jetting Mechanical wire brushing Manual brushingPoor Note: Hydro jetting is increasingly popular. But it poses some specific problems Surface preparation techniques
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 21 Surface preparation rating SA 1Light blast cleaning SA 2Thorough blast cleaning SA 2 1/2Very thorough blast cleaning SA 3Blast cleaning to visually clean St 2Thorough manual cleaning St 3Very thorough manual cleaning Optimum coatings performances achieved with SA 2 1/2 cleaning.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 22 Cost of coating is less than 20 % of total cost of painting job Typical cost structure of a Paint Job [ Euros / m2 / 150 µm ] ( Brevoort Consultancy ) Surface Cleaning –Hand cleaning 4.6 –SA 2.5 blasting 8.0 –SA 3 Near White blasting 9.2 Application –Brush / Roller 2.1 –Spray 2.6 Coating –Alkyd 1.6 –Epoxy 1.9
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 23 Estimated Service Lives of High-Performance Anticorrosion Coatings (years) Source: GH Brevoort et al Epoxy based anticorrosive coatings provide long lasting service life and corrosion protection
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 24 Single feed Airless pump & spray gun Twin feed airless technology exists but is not widely accepted, because of cost, less user- friendliness and lower robustness Typical pressure: ca 250 Bars. No pressurized airflow. High fluid pressures force the coating through a small orifice Atomization Minimum pot-life: 45 min (time to spray 25 liters of mixed paint ) Otherwise risk of gelation in the pumps, hoses and spray guns
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 25 Technology Trends & Some unmet needs Higher solids coatings Solvent-free coatings Water borne coatings Faster cure Low temperature cure to extend application window Surface tolerant coatings to reduce surface preparation costs Improved overcoatability window Flexible Epoxy Resins Improved balance between drying time and pot-life } VOC reduction } Productivity gains
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 26 Epoxy Resins in Marine & Protective Coatings Epoxy Resins are essential raw materials for these high demanding coatings segments, thanks to the outstanding benefits they provide : –Corrosion protection –Chemical resistance –Mechanical properties, e.g. adhesion –Low VOC levels achievable Marine & Protective Coatings, a large and growing market for epoxy resins
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 27 Any questions I could possibly answer on M&PC applications ? End of the Marine & Protective Coatings Part Further Technical as well as Product Stewardship related information can be found on e.g. Dow Epoxy Products Portfolio incl. Corresponding technical datasheets, Dow Liquid Epoxy Resin Brochure Dow Epoxy Novolac Brochure Dow Epoxy Resin Product Stewardship Manual Dow Epoxy Curing Agents Product Stewardship Manual
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 28
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 29 Solvents Role of solvents: Reduce the viscosity and aid the film formation Types of solvents Aromatics, ketones, glycol-ethers, acetates … are suitable. Limitations with aliphatic alcohol's which must be used in combination with better solvents. Aliphatic solvents are unsuitable with standard epoxy resins Key parameters Solvency Power Hansen Solubility Parameters / Compatibility Evaporation profile Flash-point Solvent retention effect Influence on reactivity and pot-life Smell EH & S properties
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 30 Pigments & Fillers Opacity and colour –Titanium dioxide –Iron oxides –Organic pigments Anticorrosion –Zinc dust –Zinc phosphates –Borates –Whole range of new environment friendly anticorrosive pigments Extenders –Barium sulphates –Talc –Silica –Calcium carbonates Barrier –Aluminium flakes –Miox –Mica –Micaceous iron oxide Abrasion resistance –Glass flakes
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 31 Additives Accelerators Sagging control / Rheology modifiers Wetting agents Pigment and extender anti-settling additives Film Flow additives Craters, Orange Peel, Benard Cells Foaming / Air release Surface Tension 0.1 % of additive can significantly change the performances
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 32 Typical Wt Composition of D.E.R. 671X75 based coatings Typical VOC content: 300 – 350 g / liter
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 33 Typical Wt Composition of low VOC epoxy coatings Typical VOC content: 200 – 250g / liter Low VOC coatings are based on liquid epoxy resins or on low viscous semi-solid epoxy resins
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 34 Types of epoxy coatings Shop primers –Zinc rich primers Epoxy primers –Zinc phosphate primer Glass flakes reinforced coatings. Tie coats Putty / Caulking Transparent varnishes Winter grades Etc….. Solvent borne High solids Solvent free Water Borne
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 35 Examples of commercial coatings systems (2) Zinc silicate70 µ Epoxy tie coat 50 µ High built epoxy coat200 µ Weatherable PUR 50 µ Epoxy primer30 µ Epoxy mineral flakes coat300 µ } } Interior tank lining Steel protection, e.g. off shore, above splash zone
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 36 Typical Composition of High Solids Epoxy Primer Epoxy Resin ComponentParts by weight D.E.R.331 Epoxy Resin21 Pigment grinding additive0.5 Iron Oxide Red10 Barium sulphate filler20 Mica filler20 Fumed silica thickener 2 Xylene10 Butanol 5 Curing Agent Component Ancamine® 2253 [Polyamide type]12 Note: Hydrocarbon resins [e.g. Necires grades] often employed as co-binders to reduce the brittleness of pure high solids epoxy coatings.
NEO Chemical Seminar 2007 Toine Dinnissen / March 28th 2007Page 37 Drying time versus temperature of commercial coatings Drying time of epoxy coatings severely affected by temperature Drying time strongly influenced by solids content Note: More reactive curing agents generally employed in winter systems