1. Advances in Polyurethane and Polyurea Technology
Presented by:
Jayson L. Helsel, P.E.
KTA-Tator, Inc.

2. Learning Objectives
Comprehension of the Advances in Polyurethane and Polyurea Technology Webinar will enable the participant to:
List various types of polyurethane coatings
Describe the properties of polyurethane coatings
List various types of polyurea coatings
Describe the properties of polyurea coatings
Recognize two SSPC Performance-based Paint Standards for polyurethane and polyurea coatings

3. Learning Objectives (cont.)
List the basic performance differences between polyurethane and polyurea coatings
Describe the surface preparation requirements for concrete and steel
Describe the coating application equipment typically employed
List the common applications (when and where polyurethane and polyurea coatings are used)

4. Basic Chemistry/Properties
Polyurethanes
Polyureas
Hybrid coatings

5. Polyurethanes
Polyurethanes are formed by the reaction between a polyisocyanate and hydroxyl (-OH) containing resin blend

6. Polyurethanes Disocyanate can be aromatic or aliphatic
Wide variety of formulations

7. Polyurethanes Conventional 2-part (thin film)
Waterborne formulations
Moisture cure polyurethane single component
End product can be polyurethane or polyurea chemistry
100% Solids/Elastomeric

8. Polyurethanes Conventional 2-part (thin film) Waterborne formulations
Slower cure, longer pot life
Waterborne formulations
Use water dispersible polyisocyanates
SSPC Paint Specification No. 36
“Two-Component Weatherable Aliphatic Polyurethane Topcoat, Performance-Based”

9. SSPC Paint No. 36
Weathering levels for color and gloss (accelerated or Florida exposure)
Level 1 (<1000 hrs or <24 months)
Level 2 (<2000 hrs or < 48 months)
Level 3 (>2000 hrs or > 48 months)
Color: max 2.0 ∆E, Gloss: max loss 30

10. Polyurethanes Thin-film polyurethanes properties: Typically aliphatic
Slower cure
Excellent color and gloss retention
Good chemical/solvent resistance
Good hardness/abrasion resistance

11. Polyurethanes 100% Solids/Elastomeric Typically aromatic Fast cure
Hi build, up to 100+ mils

12. Polyurethanes 100% solids polyurethane properties:
Elongation/flexibility
Excellent chemical/solvent resistance
Moisture sensitive application
Can be applied in low temperatures (below freezing)
Low VOC

13. Polyureas
Formed by the reaction between an isocyanate component and an amine-terminated (-NH2) resin blend

14. Polyureas Isocyanate can be aromatic or aliphatic
Aromatic resins will yellow but not crack
Aliphatic resins have excellent weatherability
Wide variety of formulations possible through particular resin blend
Typically 100% solids

15. Polyureas 100% solids polyurea properties: Elongation/flexibility
Excellent chemical/solvent resistance
Not sensitive to moisture during application
Can be applied in low temperatures (below freezing)
Thermal shock resistance
Minimize down time
Low VOC

16. Polyureas Polyaspartic ester based polyureas are a newer technology
Resin blend based on aliphatic polyaspartic ester
Can have much slower reaction time
Thinner film application
Typical use is analagous to conventional polyurethanes

17. Polyurethane/Polyurea Hybrids
Hybrid coatings are formed by the reaction between an isocyanate component and a resin blend component
Resin blend may contain amine-terminated and/or hydroxyl-terminated polymers
Wider range for reaction time and performance properties

18. Polyureas Fast cure Moderate cure Hybrid systems
SSPC Paint Specification No. 39
“Two-Component Aliphatic Polyurea Topcoat Fast or Moderate Drying, Performance Based”

19. SSPC Paint No. 39 Type 1: Fast Drying (less than 30 minutes)
Type 2: Moderate Drying (30 minutes to 2 hours)
Weathering levels

20. SSPC Paint No. 39 Weathering Levels Accelerated weathering levels
1A – 500 hours, max 2.0 ∆E, 20% gloss loss
2A – 1000 hours, max 3.0 ∆E, 30% gloss loss
3A – 2000 hours, max 3.0 ∆E, 40% gloss loss
Outdoor weathering levels
1N – 12 months, max 2.0 ∆E, 35% gloss loss
2N – 24 months, max 3.0 ∆E, 50% gloss loss

21. SSPC Paint No. 39 Other tests Solvent Resistance Pull-Off Adhesion
No visible topcoat removal (100 double rubs)
Pull-Off Adhesion
Average (3 pulls) ≥ 600 psi
Minimum 500 psi

22. Polyurethane vs Polyurea
Polyureas are faster cure, e.g. seconds
Polyureas not moisture sensitive
Polyurethanes cure slower but are moisture sensitive
May have fewer adhesion problems with polyurethanes

23. Surface Preparation Steel
Abrasive blast cleaning to SSPC-SP 10, Near White
Angular surface profile

24. Surface Preparation Concrete Abrasive blast cleaning
Profile/roughening required
Specialized primer may be necessary
Check moisture content

25. Application Equipment
Thin film polyurethanes and polyureas (polyaspartics)
Conventional or airless spray
100% solids polyurethanes and polyureas
Plural component spray

26. Application Equipment
Plural component spray equipment
Heats and mixes resin (part A) and curing agent (part B) components automatically in correct proportions
Paint mixture travels directly to spray gun for immediate application
Some coatings may be brush/roller applied

27. Application Equipment
Plural component spray equipment
Storage to deliver unmixed material
Proportioning Device
Pressure Pump
Mixing Device
Static mixer or air impingement
Delivery system (spray gun)
Flushing system

28. Application Equipment
Plural component application
Equipment as recommended by coating manufacturer
Requires trained/licensed applicators
Involve coating manufacturer technical representative for projects
Single application (multiple passes)

30. Application Equipment

31. Application Equipment

32. Application Equipment

33. Polyurethane Applications
Roof coatings
Pipe
Tank interior/exterior
Truck bed liners
Railcars
Parking decks
Anti-graffiti coatings
Caulk/joint/sealant materials

34. Polyurea Applications
Roof coatings
Pipe
Tank linings
Truck bed liners
Railcars
Parking decks
Caulk/joint/sealant materials

35. Polyurethane Systems
Conventional polyurethane for steel structures (exterior tank, bridges)
Surface preparation: SP 10, profile 2-3 mils
Application:
Zinc 3 – 5 mils DFT
Epoxy 4 – 6 mils DFT
Aliphatic 3 – 5 mils DFT

36. Polyurethane Systems
Waterborne polyurethane for steel /concrete (anti-graffiti coating)
Surface preparation: abrasive blast cleaning
Application:
Sealer/primer for concrete
2 coats waterborne urethane 2 – 3 mils DFT/coat
2 coats waterborne urethane 2 – 3 mils DFT/coat

37. Polyurethane Systems Waterborne polyurethane properties
Tensile strength: psi
Elongation: 150%
Taber abrasion: <45 mg loss/1000 cycles
Graffiti resistance: Level 3, ASTM D6578

38. Polyurethane Systems Waterborne polyurethane chemical resistance
MEK double rubs, 300+ cycles
Gasoline: no effect after 7 days
50% NaOH: no effect after 24 hours
10% HCl: no effect after 24 hours
Toluene: no effect after 4 hours

39. Polyurethane Systems Steel pipe (exterior) coating
Surface preparation: SP 10, profile 2.5 mils minimum
Application:
100% solids 13 – 15 mils DFT

40. Polyurethane Systems Concrete tank lining
Surface preparation: ASTM D4259/ ICRI 03732, CSP 5
Application:
Epoxy 5 – 7 mils DFT
100% solids elastomeric 60 – 80 mils DFT

41. Polyurethane Systems Elastomeric polyurethane properties
Shore A hardness: 60
Adhesion to concrete: 350 psi
Elongation: 400%
Tear strength: 150 psi
Tensile strength: 900 psi

42. Polyurethane Systems Elastomeric polyurethane chemical immersion
Acetic acid, 10%
Hyrdochloric acid, 10%
Methanol
Nitric acid, 10%
Phosphoric acid, 10%
Sulfuric acid, 30%

43. Polyurea Systems Steel tank lining
Surface preparation: SP 10, profile 3 mils
Application: 100% solids aromatic elastomeric 60 – 80 mils DFT

44. Polyurea Systems Elastomeric polyurea properties Shore D hardness: 50
Elongation: 250%
Tensile strength: psi
Tear strength: 390 psi

45. Polyurea Systems Elastomeric polyurea chemical immersion:
Acetic acid, 10%
Ammonium hydroxide, 20%
Hydrochloric acid, 10%
Phosphoric acid, 10%
Sulfuric acid, 10%

46. Polyurea Systems Concrete tank lining
Surface preparation: SP 13 / ICRI 03732, CSP 3-5
Application:
Epoxy 3 – 5 mils DFT
100% solids aromatic 60 – 100 mils DFT

47. Polyurea Systems Steel structures (exterior tank, bridges)
Surface preparation: SP 10, profile 2-3 mils
Application:
Zinc 3 – 4 mils DFT
Aliphatic 6 – 9 mils DFT

48. Polyurea Systems Polyaspartic properties
Abrasion resistance: 90 mg loss/1000 cycles
Adhesion: 825 psi
Corrosion weathering: 15 cycles ASTM D5894, Rating 10 blistering/corrosion
Freeze/thaw: 30 cycles, no adhesion loss

49. Polyurea Hybrid Systems
Concrete floor coating
Surface preparation: abrasive blasting/mechanical roughening
Application:
Epoxy 3 – 5 mils DFT
100% solids elastomeric polyurea mils DFT

50. Polyurea Hybrid Systems
Elastomeric polyurea hybrid properties
Shore D hardness: 60
Tensile strength: psi
Elongation: 100%
Tear resistance: 330 psi
Taber abrasion: 25 mg/1000 cycles

51. Summary of Key Points Polyurethanes Polyureas
Thin film conventional and waterborne
Single component moisture cure
100% solids thick film
Polyureas
No moisture sensitivity
Thin film polyaspartics

52. Summary of Key Points (cont.)
Blast cleaning generally required
Plural component application for 100% solids polyurethane/polyurea
May allow for low temperature applications
Minimize down time

53. Advances in Polyurethane and Polyurea Technology
Questions?