Advances in Polyurethane and
Polyurea Technology
Presented by:
Jayson L. Helsel, P.E.
KTA-Tator, Inc.
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
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)
Basic Chemistry/Properties
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Polyurethanes
Polyureas
Hybrid coatings
Polyurethanes
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Polyurethanes are formed by the
reaction between a polyisocyanate and
hydroxyl (-OH) containing resin blend
Polyurethanes
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Disocyanate can be aromatic or
aliphatic
Wide variety of formulations
Polyurethanes
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Conventional 2-part (thin film)
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Moisture cure polyurethane single
component
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Waterborne formulations
End product can be polyurethane or
polyurea chemistry
100% Solids/Elastomeric
Polyurethanes
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Conventional 2-part (thin film)
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Waterborne formulations
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Slower cure, longer pot life
Use water dispersible polyisocyanates
SSPC Paint Specification No. 36
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“Two-Component Weatherable Aliphatic
Polyurethane Topcoat, Performance-Based”
SSPC Paint No. 36
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Weathering levels for color and gloss
(accelerated or Florida exposure)
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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
Polyurethanes
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Thin-film polyurethanes properties:
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Typically aliphatic
Slower cure
Excellent color and gloss retention
Good chemical/solvent resistance
Good hardness/abrasion resistance
Polyurethanes
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100% Solids/Elastomeric
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Typically aromatic
Fast cure
Hi build, up to 100+ mils
Polyurethanes
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100% solids polyurethane properties:
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Elongation/flexibility
Excellent chemical/solvent resistance
Moisture sensitive application
Can be applied in low temperatures (below
freezing)
Low VOC
Polyureas
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Formed by the reaction between an
isocyanate component and an amineterminated (-NH2) resin blend
Polyureas
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Isocyanate can be aromatic or aliphatic
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Aromatic resins will yellow but not crack
Aliphatic resins have excellent
weatherability
Wide variety of formulations possible
through particular resin blend
Typically 100% solids
Polyureas
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100% solids polyurea properties:
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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
Polyureas
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Polyaspartic ester based polyureas are
a newer technology
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Resin blend based on aliphatic
polyaspartic ester
Can have much slower reaction time
Thinner film application
Typical use is analagous to conventional
polyurethanes
Polyurethane/Polyurea
Hybrids
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Hybrid coatings are formed by the
reaction between an isocyanate
component and a resin blend
component
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Resin blend may contain amine-terminated
and/or hydroxyl-terminated polymers
Wider range for reaction time and
performance properties
Polyureas
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Fast cure
Moderate cure
Hybrid systems
SSPC Paint Specification No. 39
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“Two-Component Aliphatic Polyurea
Topcoat Fast or Moderate Drying,
Performance Based”
SSPC Paint No. 39
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Type 1: Fast Drying (less than 30
minutes)
Type 2: Moderate Drying (30 minutes to
2 hours)
Weathering levels
SSPC Paint No. 39
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Weathering Levels
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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
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Outdoor weathering levels
1N – 12 months, max 2.0 ∆E, 35% gloss loss
 2N – 24 months, max 3.0 ∆E, 50% gloss loss
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SSPC Paint No. 39
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Other tests
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Solvent Resistance
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No visible topcoat removal (100 double rubs)
Pull-Off Adhesion
Average (3 pulls) ≥ 600 psi
 Minimum 500 psi
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Polyurethane vs Polyurea
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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
Surface Preparation
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Steel
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Abrasive blast cleaning to SSPC-SP 10,
Near White
Angular surface profile
Surface Preparation
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Concrete
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Abrasive blast cleaning
Profile/roughening required
Specialized primer may be necessary
Check moisture content
Application Equipment
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Thin film polyurethanes and polyureas
(polyaspartics)
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Conventional or airless spray
100% solids polyurethanes and
polyureas
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Plural component spray
Application Equipment
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Plural component spray equipment
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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
Application Equipment
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Plural component spray equipment
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Storage to deliver unmixed material
Proportioning Device
Pressure Pump
Mixing Device
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Static mixer or air impingement
Delivery system (spray gun)
Flushing system
Application Equipment
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Plural component application
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Equipment as recommended by coating
manufacturer
Requires trained/licensed applicators
Involve coating manufacturer technical
representative for projects
Single application (multiple passes)
Application Equipment
Application Equipment
Application Equipment
Polyurethane Applications
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Roof coatings
Pipe
Tank interior/exterior
Truck bed liners
Railcars
Parking decks
Anti-graffiti coatings
Caulk/joint/sealant materials
Polyurea Applications
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Roof coatings
Pipe
Tank linings
Truck bed liners
Railcars
Parking decks
Caulk/joint/sealant materials
Polyurethane Systems
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Conventional polyurethane for steel
structures (exterior tank, bridges)
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Surface preparation: SP 10, profile 2-3 mils
Application:
Zinc primer @ 3 – 5 mils DFT
 Epoxy intermediate @ 4 – 6 mils DFT
 Aliphatic polyurethane @ 3 – 5 mils DFT
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Polyurethane Systems
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Waterborne polyurethane for steel
/concrete (anti-graffiti coating)
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Surface preparation: abrasive blast cleaning
Application:
Sealer/primer for concrete
 2 coats waterborne urethane primer @ 2 – 3 mils
DFT/coat
 2 coats waterborne urethane finish @ 2 – 3 mils
DFT/coat
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Polyurethane Systems
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Waterborne polyurethane properties
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Tensile strength: 5950 psi
Elongation: 150%
Taber abrasion: <45 mg loss/1000 cycles
Graffiti resistance: Level 3, ASTM D6578
Polyurethane Systems
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Waterborne polyurethane chemical
resistance
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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
Polyurethane Systems
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Steel pipe (exterior) coating
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Surface preparation: SP 10, profile 2.5 mils
minimum
Application:
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100% solids polyurethane @ 13 – 15 mils DFT
Polyurethane Systems
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Concrete tank lining
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Surface preparation: ASTM D4259/ ICRI
03732, CSP 5
Application:
Epoxy primer @ 5 – 7 mils DFT
 100% solids elastomeric polyurethane @ 60 – 80
mils DFT
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Polyurethane Systems
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Elastomeric polyurethane properties
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Shore A hardness: 60
Adhesion to concrete: 350 psi
Elongation: 400%
Tear strength: 150 psi
Tensile strength: 900 psi
Polyurethane Systems
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Elastomeric polyurethane chemical
immersion
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Acetic acid, 10%
Hyrdochloric acid, 10%
Methanol
Nitric acid, 10%
Phosphoric acid, 10%
Sulfuric acid, 30%
Polyurea Systems
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Steel tank lining
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Surface preparation: SP 10, profile 3 mils
Application: 100% solids aromatic
elastomeric polyurea @ 60 – 80 mils DFT
Polyurea Systems
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Elastomeric polyurea properties
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Shore D hardness: 50
Elongation: 250%
Tensile strength: 2125 psi
Tear strength: 390 psi
Polyurea Systems
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Elastomeric polyurea chemical immersion:
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Acetic acid, 10%
Ammonium hydroxide, 20%
Hydrochloric acid, 10%
Phosphoric acid, 10%
Sulfuric acid, 10%
Polyurea Systems
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Concrete tank lining
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Surface preparation: SP 13 / ICRI 03732,
CSP 3-5
Application:
Epoxy primer @ 3 – 5 mils DFT
 100% solids aromatic polyurea @ 60 – 100 mils
DFT
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Polyurea Systems
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Steel structures (exterior tank, bridges)
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Surface preparation: SP 10, profile 2-3 mils
Application:
Zinc primer @ 3 – 4 mils DFT
 Aliphatic polyaspartic @ 6 – 9 mils DFT
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Polyurea Systems
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Polyaspartic properties
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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
Polyurea Hybrid Systems
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Concrete floor coating
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Surface preparation: abrasive
blasting/mechanical roughening
Application:
Epoxy primer @ 3 – 5 mils DFT
 100% solids elastomeric polyurea hybrid @
30+ mils DFT
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Polyurea Hybrid Systems
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Elastomeric polyurea hybrid properties
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Shore D hardness: 60
Tensile strength: 2300 psi
Elongation: 100%
Tear resistance: 330 psi
Taber abrasion: 25 mg/1000 cycles
Summary of Key Points
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Polyurethanes
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Thin film conventional and waterborne
Single component moisture cure
100% solids thick film
Polyureas
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100% solids thick film
No moisture sensitivity
Thin film polyaspartics
Summary of Key Points (cont.)
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Blast cleaning generally required
Plural component application for 100%
solids polyurethane/polyurea
May allow for low temperature applications
Minimize down time
Advances in Polyurethane and
Polyurea Technology
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Questions?