1、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 coatingsDescribe the properties of
2、 polyurethane coatingsList various types of polyurea coatingsDescribe the properties of polyurea coatingsRecognize two SSPC Performance-based Paint Standards for polyurethane and polyurea coatings,Learning Objectives (cont.),List the basic performance differences between polyurethane and polyurea co
3、atings Describe the surface preparation requirements for concrete and steelDescribe the coating application equipment typically employedList the common applications (when and where polyurethane and polyurea coatings are used),Basic Chemistry/Properties,Polyurethanes Polyureas Hybrid coatings,Polyure
4、thanes,Polyurethanes are formed by the reaction between a polyisocyanate and hydroxyl (-OH) containing resin blend,Polyurethanes,Disocyanate can be aromatic or aliphatic Wide variety of formulations,Polyurethanes,Conventional 2-part (thin film) Waterborne formulations Moisture cure polyurethane sing
5、le component End product can be polyurethane or polyurea chemistry 100% Solids/Elastomeric,Polyurethanes,Conventional 2-part (thin film) Slower cure, longer pot life Waterborne formulations Use water dispersible polyisocyanates SSPC Paint Specification No. 36 “Two-Component Weatherable Aliphatic Pol
6、yurethane Topcoat, Performance-Based”,SSPC Paint No. 36,Weathering levels for color and gloss (accelerated or Florida exposure) Level 1 (2000 hrs or 48 months) Color: max 2.0 E, Gloss: max loss 30,Polyurethanes,Thin-film polyurethanes properties: Typically aliphatic Slower cure Excellent color and g
7、loss retention Good chemical/solvent resistance Good hardness/abrasion resistance,Polyurethanes,100% Solids/Elastomeric Typically aromatic Fast cure Hi build, up to 100+ mils,Polyurethanes,100% solids polyurethane properties: Elongation/flexibility Excellent chemical/solvent resistance Moisture sens
8、itive application Can be applied in low temperatures (below freezing) Low VOC,Polyureas,Formed by the reaction between an isocyanate component and an amine-terminated (-NH2) resin blend,Polyureas,Isocyanate can be aromatic or aliphatic Aromatic resins will yellow but not crack Aliphatic resins have
9、excellent weatherability Wide variety of formulations possible through particular resin blend Typically 100% solids,Polyureas,100% solids polyurea properties: Elongation/flexibility Excellent chemical/solvent resistance Not sensitive to moisture during application Can be applied in low temperatures
10、(below freezing) Thermal shock resistance Minimize down time Low VOC,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 polyurethane
11、s,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,Polyureas,Fast cure Moderate cu
12、re Hybrid systemsSSPC Paint Specification No. 39 “Two-Component Aliphatic Polyurea Topcoat Fast or Moderate Drying, Performance Based”,SSPC Paint No. 39,Type 1: Fast Drying (less than 30 minutes) Type 2: Moderate Drying (30 minutes to 2 hours) Weathering levels,SSPC Paint No. 39,Weathering Levels Ac
13、celerated 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,SSPC Paint No. 39,Other tests Solvent Resist
14、ance No visible topcoat removal (100 double rubs) Pull-Off Adhesion Average (3 pulls) 600 psi Minimum 500 psi,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 p
15、olyurethanes,Surface Preparation,Steel Abrasive blast cleaning to SSPC-SP 10, Near White Angular surface profile,Surface Preparation,Concrete Abrasive blast cleaning Profile/roughening required Specialized primer may be necessary Check moisture content,Application Equipment,Thin film polyurethanes a
16、nd polyureas (polyaspartics) Conventional or airless spray 100% solids polyurethanes and polyureas Plural component spray,Application Equipment,Plural component spray equipment Heats and mixes resin (part A) and curing agent (part B) components automatically in correct proportions Paint mixture trav
17、els directly to spray gun for immediate application Some coatings may be brush/roller applied,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) Flushi
18、ng system,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),Application Equipment,Application Equipment,Appl
19、ication Equipment,Polyurethane Applications,Roof coatings Pipe Tank interior/exterior Truck bed liners Railcars Parking decks Anti-graffiti coatings Caulk/joint/sealant materials,Polyurea Applications,Roof coatings Pipe Tank linings Truck bed liners Railcars Parking decks Caulk/joint/sealant materia
20、ls,Polyurethane Systems,Conventional polyurethane for steel structures (exterior tank, bridges) 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,Polyurethane Systems,Waterborne polyurethane for stee
21、l /concrete (anti-graffiti coating) 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,Polyurethane Systems,Waterborne polyurethane properties Tensile strength:
22、 5950 psi Elongation: 150% Taber abrasion: 45 mg loss/1000 cycles Graffiti resistance: Level 3, ASTM D6578,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 hou
23、rs Toluene: no effect after 4 hours,Polyurethane Systems,Steel pipe (exterior) coating Surface preparation: SP 10, profile 2.5 mils minimum Application: 100% solids polyurethane 13 15 mils DFT,Polyurethane Systems,Concrete tank lining Surface preparation: ASTM D4259/ ICRI 03732, CSP 5 Application: E
24、poxy primer 5 7 mils DFT 100% solids elastomeric polyurethane 60 80 mils DFT,Polyurethane Systems,Elastomeric polyurethane properties Shore A hardness: 60 Adhesion to concrete: 350 psi Elongation: 400% Tear strength: 150 psi Tensile strength: 900 psi,Polyurethane Systems,Elastomeric polyurethane che
25、mical immersion Acetic acid, 10% Hyrdochloric acid, 10% Methanol Nitric acid, 10% Phosphoric acid, 10% Sulfuric acid, 30%,Polyurea Systems,Steel tank lining Surface preparation: SP 10, profile 3 mils Application: 100% solids aromatic elastomeric polyurea 60 80 mils DFT,Polyurea Systems,Elastomeric p
26、olyurea properties Shore D hardness: 50 Elongation: 250% Tensile strength: 2125 psi Tear strength: 390 psi,Polyurea Systems,Elastomeric polyurea chemical immersion: Acetic acid, 10% Ammonium hydroxide, 20% Hydrochloric acid, 10% Phosphoric acid, 10% Sulfuric acid, 10%,Polyurea Systems,Concrete tank
27、lining Surface preparation: SP 13 / ICRI 03732, CSP 3-5 Application: Epoxy primer 3 5 mils DFT 100% solids aromatic polyurea 60 100 mils DFT,Polyurea Systems,Steel structures (exterior tank, bridges) Surface preparation: SP 10, profile 2-3 mils Application: Zinc primer 3 4 mils DFT Aliphatic polyasp
28、artic 6 9 mils DFT,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,Polyurea Hybrid Systems,Concrete floor coating Surface prepara
29、tion: abrasive blasting/mechanical roughening Application: Epoxy primer 3 5 mils DFT 100% solids elastomeric polyurea hybrid 30+ mils DFT,Polyurea Hybrid Systems,Elastomeric polyurea hybrid properties Shore D hardness: 60 Tensile strength: 2300 psi Elongation: 100% Tear resistance: 330 psi Taber abr
30、asion: 25 mg/1000 cycles,Summary of Key Points,Polyurethanes Thin film conventional and waterborne Single component moisture cure 100% solids thick film Polyureas 100% solids thick film No moisture sensitivity Thin film polyaspartics,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,Advances in Polyurethane and Polyurea Technology,Questions?,
