1. Innovative Coatings from Low Molecular Weight EPDM Western Coatings Symposium 2015 Las Vegas, Nevada October 27, Zhiyong Zhu Lion Elastomers, LLC., Geismar, LA

2. EPDM Properties Desired in Coating Applications
√ Rubber flexibility, especially at low temperature
√ Weather durability
√ Hydrophobic and water proof
√ Low Moisture Permeability
√ Excellent electrical properties
A rubber coating that provides similar rubber properties of silicone coatings but at a lower cost level.

3. What is EPDM? EPDM Ethylene Propylene Diene M*
Compositions, crystalinity and molecular weight determine the properties of EPDM. The special properties of EPDM are derived from the saturated backbone structure.
* In ASTM Nomenclature system, M designates a saturated polymer backbone. In contrast, R designates polymers that contain unsaturated backbone, e.g. NR, SBR.

4. Curing of Trilene® Polymer: Peroxide Curing
Curing of EPDM relies on a free radical crosslinking chemistry. The peroxide generates polymer free radicals either by adding to a double bond or through the abstraction of Hydrogen atoms, often adjacent to the double bond (α-H).

5. Curing of EPDM: Photo / UV Curing
BAPO: Bis-Acyl-Phosphine Oxide, IRGACURE® 819, Peak adsorption 371, 400 nm, CAS#
Curing through photo / UV follows the same free radical crosslinking chemistry. The only difference is the source of free radicals. Irgacure® 819 (BAPO) has the best absorption and allows a curing with natural sunshine.

6. Starting Formulations from Peroxide and UV Curing
Material
Function
Supplier
Peroxide F.
UV F.
Part A
Trilene® T65
Lion Copolymer
32.92
28.37
Ricon® 156
Co-agent
Cray Valley
2.74
2.36
SR-350
Sartomer
0.69
Mineral Spirit
Solvent
Lard Oil
20.67
16.55
SIH6115.0
Exempted Solvent
Gelest
10.00
21.28
Disper BYK® 118
Dispersant
BYK
1.10
0.70
Ti-Pure® R-706
White Pigment
Dupont
8.23
9.46
Coupsil® 6508
Reinforcing Filler
Evonik
Ultrex® 96
Kaolin
16.46
Irgacure® 819
Photo Initiator
BASF
12% Co Ten-Cem
Catalyst
OMG
0.27
18% Zn Ten-Cem
Toluene
Co-solvent
Multi
Part B
Peroxan® PPIN
Curative
Pergan
1.65
5.00
Total
100
Solid Content (w/w%)
64.3%
52.7%
VOC (g/L)
243
247
Brookfield Viscosity (cP)
4600
5400
Specific Gravity
0.946
0.955

7. Typical Performance of Coatings
Item
UV/Sunshine Cured
Peroxide Cured
Standard
Solid Content
Up to 80 wt%
ASTM D2369
VOC
<250 g/L
ASTM D3960
Specific Gravity
~0.94
ASTM D1475
Viscosity (25oC) cP cP
ASTM D2196
Tensile Strength
psi
psi
ASTM D412
Elongation at Break % %
Paint Dry Time
(to tacky free, 75oF)
30-60 min
3-4 hours
(Walk-able, 75oF)
8 hours
16 hours
Paint Pot Life (75oF)
> 4 hours
> 1 hour
Adhesion to substrates
OK with aged EPDM, wood, metal, concrete, and typical acrylic or epoxy primers
ASTM D903
Moisture Permeability
< 0.2 perm
ASTM E96
Paint Shelf Life (70oF)
3 years
1 year

8. Examples of Coating Films
Color samples from peroxide formulations on cold-rolled steel
White sample from UV formulation on aged EPDM roofing sheet (no cleaning or pre-treatment)

9. EPDM Coating Compared with Other Coatings
Excellent
Very Good
Good
Fair
Poor
5 = best; 1 = poorest.

10. UV Curing of Trilene® Polymer
A starting UV formulation with Irgacure® 819 and white TiO2 pigment after 2 days in sunshine.
Development of curing in sunshine and shaded area.
The Irgacure® 819 enables a fast curing under natural sunshine. The curing after 2 days achieves sufficient mechanical strength. Curing in shaded area is also sufficiently fast.

11. Effect of EPDM Chemical Structure
E/P Ratio
54/46 
45/55
75/25
75/25 
Diene Type
 DCPD
ENB
ENB 
Diene %
 9.75
4.5
9.5
4.0
 10.5 Mv
6411
8000
7700
7500
Solid%
55.9%
45.4%
Estimated VOC g/L
236
379
Viscosity (mPas, #64, 50%)
3260
4420
6440
5760
4280
Curing speed in 30 Minutes
OK 
 OK
Tensile (psi, 5 days)
 1086
 327
592
 411
 524
Elongation at break (%)
114
 43
 100
 44
 86
Modulus (psi, 50%)
794 
126 
 426
 na
 432
The functionality and molecular weight dominate the final coating performance. Trilene® T65 was found to be the optimized resin so far, probably due to the more reactive and high content of DCPD.

12. Study of Formulation: Fillers
Coupsil
Coupsil (phr)
Effect of filler type and filler load on the properties of the peroxide coatings.
Both filler type and filler loading could have a deep effct on the final mechanical strength of coating.

13. Field Application with Airless Spray
Airless Spray Video 1
Airless Spray Video 2

14. Hydrophobicity – Contact Angle Test ASTM-D7490
Urethane Paint
LINK TO A VIDEO
Hydrophilic
Trilene® based membranes are more hydrophobic than acrylic and PU paints, and water is easier to exclude from the surface.

15. Hydrophobicity – Ponding Water Resistance ASTM D7281
EPDM Coating
A Commercial Acrylic Roof Coating
A Commercial Silicone Roof Coating
* Water was let sitting on coatings at 40oC for 30 days.
Trilene® based membranes showed good dimension stability as silicone rubber, while acrylic coatings showed significant swelling.

16. Adhesion to Substrates and Primers ASTM-D4541
Pulling Test (psi)
Results
Aged EPDM Sheet
(pre-cleaned with NaOH)
 2300 OK
(No Pretreatment)
2150
New TPO Sheet
1350 
Aluminum Panel (Q Panel)
 1420
Cold Rolled Steel
 2200
Wood Panel
 1900
Concrete Panel
 1600
Master Chem KILZ2
 2100
Master Chem KILZ Complete
Behr 436
 2250
Roman Rx35
 2450
Glidden Gripper
 2000
Zinsser B.I.N.
2240 
Zinsser 1.2.3
 2260
Peroxide coatings showed good adhesion to various substrates and primers. UV samples are still being tested.

17. Roof Coating: Field Application
Confidential
DURABILITY; FLEXIBILITY; AND BETTER WATER PROOFING

18. Protective Coating: Field Application
Before Coating
After Coating

19. Lion’s Efforts: Prepare EPDM Latex for Aqueous Coatings
EPDM Polymer
Royalene®, Trilene® Mw
5,000 and up
Solid Content
> 30%
Surfactant type
Non-Iononic
Surfactant Content (w/w)
5 – 50%
Brookfield Viscosity (25oC, cP)
100 – 10,000
pH value
6.8 – 7.0
Density (g/mL)
0.90 – 0.95
Average Particle Size
< 2 µm
Confidential
High Solid, Low surfactant, reasonable processing cost
Provisional US Patent Application: A “Method for making a cross-linked ethylene propylene diene TERPOLYMER latex”
Provisional US Patent Application: A “solvent-free Method for making ethylene propylene diene TERpolymer latex”

20. Miscibility of EPDM Latex with Acrylic Latex
Mixture
Acrylic Latex
Confidential
DSC curve for mixture of 20% EPDM latex in acrylic latex
Viscosity change for mixture of EPDM latex in acrylic latex
Disappearance of Tg peak of EPDM and reduction of viscosity showed good miscibility of EPDM latex in acrylic latex.

21. Conclusions
Coatings based low molecular weight EPDM polymer were successfully developed from peroxide crosslinking and photo initiator crosslinking.
Properties and advantages of EPDM coatings have been demonstrated, and influences from crosslinking agents, co-agents, polymer chemical structure and fillers are discussed.
EPDM Coatings offer potentials in various coating applications, including roofing, protective, decorative coatings etc.

22. Welcome to our booth for samples!
THANK YOU !!!
Welcome to our booth for samples!