Hydrophobic Elastomeric Coatings for Chemical Resistance
Aayush A. Shah, Fabio Aguirre, Avery Watkins and Amber Stephenson
Polyurethanes Application Development and Technical Services
Opportunity
Relative Polarity of VORAPELTM
Assets for primary and secondary
containment of chemicals, such as tanks
and pipelines are coated to prevent
corrosion. However, the maintenance of
the coatings on these assets required
rapid return to service, which current
epoxy solutions do not provide.
Product
Surface
Tension
(mN/m)
EO Polyether
Polyol (OHV
= 260-280)
PO Polyether
Polyol (OHV
= 225-250)
VORAPELTM
T5001(OHV =
280-300)
VORAPELTM
D3201 (OHV
= 53-59)
Comparison between fast-set
elastomers and Epoxy Coatings 1
*
Comparison to Standard Polyurea
Dispersive Polar
%
(mN/m) (mN/m) Polarity
39.4
23.5
16.0
40.5
34.1
26.9
7.2
21
32.3
27.6
4.7
14.7
31.4
28.8
2.6
8.3
VORAPELTM polyols reduce surface tension
and hence increased hydrophobicity of
fast-set elastomeric coatings making them
less prone to chemical attack
Although standard polyureas are known to
cure rapidly they do not have the chemical
resistance of epoxy coatings
Chemical Resistance of VORAPELTM based Coatings
VORAPELTM polyols dramatically improve acid resistance of fast-set elastomeric coatings.
Comparison to Epoxy Coatings
Effect of VORAPELTM Polyols on
Hydrolytic Chemical Resistance
System
Part A
Part B
(Isocyanate Side)
Std. Polyurea
Std. Polyamine
15.9 % NCO std.
polyether polyol
prepolymer
VORAPELTM
Prepolymer
Polyurea
Std. Polyamine
15.9% NCO
VORAPELTM
prepolymer
VORAPELTM
Hybrid Polyurea
VORAPELTM
polyol
+ Std. Polyamine
15.9% NCO
VORAPELTM
prepolymer
* Based on results shown in the poster
Profile of capacitance (lower) over time determine better coating performance (EIS)
VORAPELTM polyols and prepolymers can be
used to make hydrophobic fast-set
elastomeric coatings with high chemical
resistance. The formulation can reach up to
~ 55% by weight of VORAPELTM
TM
VORAPEL hydrophobic
VORAPELTM based elastomeric coatings perform as good or better than epoxy materials in
certain conditions.
Panel Chemical Resistance
polyols
Conclusions
• Fast-set elastomeric coatings based
on
VORAPELTM
polyols
shows
enhanced chemical resistance due to
higher hydrophobicity.
VORAPELTM polyols form hydrophobic
polyurea hybrids
470
3
280-300
600
330
Long-Term Chemical Resistance
Reagent
4 Months immersion test of
Temp
coated panels
Third Party Lab Results
VORAPELTM
Based Coating
TEMPLATE DESIGN © 2008
www.PosterPresentations.com
Best – in – Class
Epoxy for Tank Lining
Hydrophobic VORAPELTM polyols significantly
improve hydrolytic stability of fast-set
elastomeric coatings.
B20 Bio-diesel (50°C)
Ethanol w/3% Gasoline (50°C)
Tap water (90°C)
DI water (60°C)
122°F
122°F
194°F
140°F
• VORAPELTM based coatings allows
higher performance and/or reduce
thickness in applications where std.
polyureas are typically used
Chalking
2000
Flaking
53-59
Cracking
2
Rust
VORAPEL™
D3201
VORAPEL™
T5001
Viscosity
OH
Average
at
Functionality Number
MW
100º F
Range
(cSt)
Blisters
Product
• Hydrophobic elastomeric coatings
can replace epoxy systems, in some
maintenance jobs where chemical
resistance, fast return to service and
good damage tolerant is critical.
• VORAPELTM prepolymers can be used
as a drop-in replacement in Std.
polyurea systems
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References
1.
Ha Q. Pham and Maurice J. Marks, Epoxy Resins,
Ullmann’s Encyclopedia of Industrial Chemistry,
156-244, Vol. 13.