Transcript Polyurethane,Polyureaand HybridTechnology

Polyurethane, Polyurea and
Hybrid Lining Technology
Presented by: Dudley Primeaux, PCS
VersaFlex Incorporated
Introduction
• This webinar reviews
application of polyurea,
polyurethane, or
polyurea/polyurethane
hybrid thick film coatings
to steel or concrete
surfaces using pluralcomponent spray
application
SSPC Standards
• SSPC-Paint 45, Two-Component, ThickFilm Polyurea and Polyurea/Polyurethane
Hybrid Coatings, Performance-Based
– Expected to be released by December 2013
• SSPC-PA 14, Application of Thick Film
Polyurea and Polyurethane Coatings to
Concrete and Steel Using PluralComponent Equipment
SSPC-Paint 45
• A coating standard that contains minimum
performance requirements for polyurea
and polyurea/polyurethane hybrid
coatings
SSPC-Paint 45 Coating Types
• 2 types defined
– Type 1
• Polyurea
– 1a, Fast Cure
» Dry in less than 2 minutes
– 1b, Moderate Cure
» Dry time is 2 minutes – 30 minutes
– Type 2
• Polyurea/Polyurethane Hybrid
– 2a, Fast Cure
» Dry in less than 2 minutes
– 2b, Moderate Cure
» Dry time is 2 minutes-30 minutes
Polyurea
• A coating material which is the reaction
product of an isocyanate and a
polyamine.
Polyureas
• Isocyanate Component can be aromatic
or aliphatic
• Resin / Polyamine Component can be
aromatic or aliphatic
– Aromatic based systems will yellow or fade
but not crack
– Aliphatic based systems have excellent
weatherability
Polyurea Properties
•
•
•
•
•
•
Good elongation and flexibility
Excellent chemical/solvent resistance
Can be applied in low temperatures
Good thermal shock resistance
Turn Around Time
100% Solids
Polyurea Standard
• SSPC Paint No. 39, Two-Component
Aliphatic Polyurea Topcoat Fast or
Moderate Drying, Performance Based
– Type 1: Fast Drying
• Less than 30 minutes
– Type 2: Moderate Drying
• 30 minutes to 2 hours
SSPC Paint 39
Exposure Test Performance
Level
Exposure
Time
Color
Retention Per
ASTM D2244
Maximum
Gloss
Reduction
From
Original
Reading Per
ASTM D523
ASTM D4587
Level 1A
500 h
≤ 2.0 ∆E
20%
ASTM D4587
Level 2A
1000 h
≤ 3.0 ∆E
30%
ASTM D4587
Level 3A
2000 h
≤ 3.0 ∆E
40%
ASTM D1014
Level 1N
12 mo
≤ 2.0 ∆E
35%
ASTM D1014
Level 2N
24 mo
≤ 3.0 ∆E
50%
From Table 1: Summary of Performance Testing Results to be Reported
Polyurethane
• A coating binder material formed by the
reaction of an isocyanate with hydroxylcontaining substances (polyols) to
produce an organic polymer compound
known as a urethane
Types of Polyurethanes
• Conventional 2-part (thin film)
• Moisture cure polyurethane single
component
• 100% solids/elastomeric (thick film)
Conventional 2-Part Polyurethane
• Waterborne formulations
– Use water dispersible polyisocyanate
• Slower cure
• Longer potlife
• Typically aliphatic
– SSPC Paint Specification No. 36
• Two Component Weatherable Aliphatic
Polyurethane Topcoat, Performance-Based
SSPC Paint No. 36
Accelerated UV-A Testing
Performance
Level
Hours to
Months to
Noticeable Change Noticeable Change
Level 1
500 to 999
12 to 23
Level 2
1000 to 1999
24 to 47
Level 3
2000 or more
48 or more
From Table 1: Time Corresponding to Each Performance Level
SSPC Paint No. 36
Exposure Test
Performance Level
Exposure
Time
Color Change
ASTM D2244
Maximum Gloss
Reduction
ASTM D523
Accelerated Weathering
ASTM D4587
Level 1
500 h
Less than 2.0 ΔE
25% from
original reading
Accelerated Weathering
ASTM D4587
Level 2
1000 h
Less than 2.0 ΔE
25% from
original reading
Accelerated Weathering
ASTM D4587
Level 3
2000 h
Less than 2.0 ΔE
25% from
original reading
South Florida
Weathering ASTM
D1014
Level 1
12 mo
Less than 2.0 ΔE
35% from
original reading
South Florida
Weathering ASTM
D1014
Level 2
24 mo
Less than 2.0 ΔE
35% from
original reading
South Florida
Weathering ASTM
D1014
Level 3
48 mo
Less than 2.0 ΔE
35% from
original reading
From Table 2: Summary of Performance Testing Results to be Reported
Conventional 2-Part
Polyurethane
• Excellent color and gloss retention
• Good chemical/solvent resistance
• Good hardness/abrasion resistance
Characteristics of MoistureCured Urethane Coatings
• Moisture-Cured Urethane (MCU)
Coatings
– Advantages
– Limitations
Polyurethane Advantages
• Turn Around Time
• 100% Solid
• Can Have Some Limited Ability to Apply
During Winter Months
• Unique “Self-Inspecting” Property
Hybrid
• A blend of polyurea and polyurethane
100% Solids/Elastomeric
•
•
•
•
•
•
•
Typically aromatic
Fast cure
High build, up to 100+ mils (2.5+ mm)
Good elongation and flexibility
Excellent chemical and solvent resistance
Can be applied in low temperatures
Low VOC
Thick Film
• Greater than 20 mils (500 µm) dry film
thickness
• Shown here is a wet film
gage used in some
Moderate Cure systems
• Fast Cure systems would
require the use of either a
Type 1 magnetic or Type 2
electronic gage, or an
ultrasonic gage
Service Environments
• SSPC-Paint 45 coatings are suitable for
application in the following SSPC
environmental zones:
– 1A (Interior, normally dry)
– 1B (Exterior, normally dry)
– 2A (Frequently wet by fresh water, excluding
immersion)
– 2B (Frequently wet by salt water, excluding
immersion)
– 2C (Fresh water immersion)
– 2D (Salt water immersion)
Surface Preparation of Steel
• Removal of Visible Contaminants
– SSPC-SP 1, Solvent Cleaning
• Removal of Non-Visible Contaminants
– SSPC Guide 15, Field Methods for Retrieval and Analysis
of Soluble Salts on Steel and Other Nonporous
Substrates
• Minimum Surface Profile of 3 mils (76 µm)
– ASTM D4417, Standard Test Methods for Field
Measurement of Surface Profile of Blast Cleaned Steel
– Method B
– SSPC-PA 17, Procedure for Determining Conformance to
Steel Profile/Surface Roughness/Peak Count
Requirements
Surface Preparation of Concrete
• Verify that the concrete substrate is sound and
solid
– ASTM C805, Standard Test Method for Rebound
Number of Hardened Concrete
• Repair surface defects such as: bugholes, voids
and cracks
• Clean the surface so it is free of dust, dirt, grease
and oils, contaminants, laitance, and loosely
adhering concrete (SSPC-SP 13)
• Create a surface roughness within ICRI 310.2,
CSP range of 2-6
Rebound Hammer and ICRI
310.2 CSP replicate plaques
• ASTM D7682, Standard Test Method
for Replication and Measurement of
Concrete Surface Profiles Using
Replica Putty
Coating Material Receipt
• Check that coatings delivered:
– Are in original, unopened containers with labels
intact
– That containers are not damaged
– Have readily accessible PDS’s and SDS’s
– Each container is marked, showing: coating
identification, date of manufacturer, batch number,
and basic chemical composition
– Coatings are stored in accordance with applicable
federal, state and local safety regulations
– Coatings are stored in accordance with
manufacturer’s recommendations
– Are within applicable shelf life
Mixing
• Mix each individual component of the
coating system in accordance with
manufacturer’s instructions
• Verify proper mix ratio of coating
components prior to placement into plural
component equipment
Mixing
Pre- Application Checks
• Prior to application of the coating check:
– Ambient conditions
• Coating is not to be applied in wind, snow, fog,
mist or rain.
• Coating is not to be applied to wet or damp
substrates
– Temperature
• The surface temperature, temperature of the
coating and ambient air temperature must be
within coating manufacturers requirements
Pre-Application Checks (Cont’d)
• Humidity
– Coating shall not be applied when the surface
temperature is less than 5 degrees Fahrenheit (3
degrees Centigrade) above the dew point
• Concrete Substrate Moisture
– The moisture level of the concrete shall comply with
the coating manufacturer’s requirements as
determined by the measurement method specified
on the PDS
• Steel Substrate Moisture
– Apply coating to dry substrates that are free of any
water in seams, fasteners or joints
Application Equipment
• Coating are applied by high-pressure or lowpressure plural component spray equipment
• Equipment is capable proportioning and heating
the fluid
• The spray gun is capable of mix and dispense
of the thick film coating to the desired DFT and
pattern specified on PDS
– DFT can be achieved in 1-3 overlapping
passes
Mixing at the Gun
Air purge gun
Mechanical purge gun
Test Area
• Prior to spraying project area, create a
test area
– ~11 square feet (1 square meter) in size
– Test adhesion
• For steel test in accordance of ASTM D4541,
Method D or E
– Average of 3 pulls
• For concrete test in accordance of ASTM D7234
– Average of 3 pulls
Application
• Primer
– Applied in accordance with PDS
– Applied in a visually continuous film with
overlapping at the edges of the spray pattern
• Topcoat
– Applied in accordance with PDS
– Not applied until primer has cured
– Applied within recoat window of primer
Coating Thickness
• The coating thickness is verified by:
– Steel: SSPC-PA 2, Procedure for
Determining Conformance to Dry Coating
Thickness Requirements
- Type 1 (magnetic) or Type 2 (electronic)
– Concrete: SSPC-PA 9, Measurement of Dry
Coating Thickness on Cementitious
Substrates Using Ultrasonic Gages
Coating Continuity
• Inspect coating for a cured film that is
continuous and pinhole free
– NACE SP0188, Discontinuity (Holiday)
Testing of New Protective Coatings on
Conductive Substrates
– ASTM D4787, Standard Practice for
Continuity Verification of Liquid or Sheet
Linings Applied to Concrete Substrates
Summary
• By following appropriate test methods and
good practices, polyurea, polyurethane
and hybrid coatings can provide excellent
corrosion protection for concrete and steel
substrates
• This protection includes a variety of
interior and exterior coating work, as well
as immersion lining application areas
Questions?