Novel Toughening Technology for Epoxy Thermosets Steve Hoyles, Nikhil Verghese, Michael Ross, Marv Dettloff and Ha Pham The Dow Chemical Company 11/22/2018

Outline Self assembled toughening technology background Example Application Area #1: M&PC Coatings Example Application Area #2: Powder Coatings 11/22/2018

Purpose:. Utilize self assembled block. copolymer technology to Purpose: Utilize self assembled block copolymer technology to increase the ductility of epoxy thermosets without negatively impacting other properties. 11/22/2018

There are two approaches to increased ductility… Flexibilization Backbone Stiffness Crosslink Density Plasticizers and diluents Toughening Interfacial strength Particle size Polydispersity 11/22/2018

Other Technologies Plastisizer Aliphatic backbone CTBN Core Shell Embrittlement Chem Resist Aliphatic backbone Reactivity CTBN Corrosion Core Shell Rubbers Viscosity 11/22/2018

Flexibility versus Toughening Flexbilization 11/22/2018

Self Assembled Block Copolymers Cured epoxy curing Curing agent Epoxy 11/22/2018

Macrophase Separation (example CTBN technology) Cure Self Assembly (current technology) Cure Epoxy Curing Agent Polymer 11/22/2018

Self-Assembly vs. Macrophase Separation Macrophase (e.g. CTBN) Low concentrations (5-10 vol%) self -assemble into dispersed morphologies Less detrimental effect on glass transition temperature, Tg, modulus, E Controlled structure size Can retain optical clarity No pollution of continuous phase High concentrations (10-20 vol%) macro phase separation Detrimental effects on glass transition temperature, Tg, modulus, E Hard to control structure size loss of optical clarity agglomeration 11/22/2018

TEM Images of Self Assembled Morphologies Wormlike Micelle Spherical Micelle 11/22/2018

Second Phase Toughening Mechanism Tensile Direction 11/22/2018

Typical Tensile behavior 5 10 15 20 25 30 Strain (%) Stress (Pa) Modified Unmodified Reduction of yield stress 11/22/2018

Effect on Material Properties 11/22/2018

Effect on Tg and Modulus Results from a plaque 1.E+09 1.E+08 Storage Shear Modulus, G' (Pa) 1.E+07  1.E+06 DER 383 epoxy resin cured with Phenolic Hardener: CONTROL Modified with 5wt.% Toughening Agent 1.E+05 50 100 150 200 250 300 Temperature (°C)  Trademark of The Dow Chemical Company 11/22/2018

Outline Self assembled toughening technology background Example Application Area #1: M&PC Coatings Example Application Area #2: Powder Coatings 11/22/2018

XU19108.00 Effective at 5-10 Vol% of total dry solids neat viscosity = 4000 cPs Density = 1.03 g/l 100% solids can be incorporated during paint grind phase or let down 11/22/2018

Clear Coat Testing Ancamine 1618* Ancamide 2353* NC541LV ** modified IPDA adduct cut in benzyl alcohol Ancamide 2353* TETA polyamide NC541LV ** phenalkamine * Air Products ** Cardolite 11/22/2018

Clear Film Formulations Prepared by Draw Down B1000 panels and free films from tin plate Cured at 60°C DFT = 110 +/- 5 microns 11/22/2018

Typical Impact Testing Result panels shown cured with Ancamine 1618 110 +/- 5 microns 11/22/2018

Free Film Tensile Results 11/22/2018

Pigmented system Based on D.E.R. 331 cured with Ancamide 2353 Pigmented with red iron oxide, extender and an anticorrosive pigment XU19108 was added at both 6.8% and 13.3% by volume dry paint Coatings spray applied on bare cold rolled steel panels Cured for 14 days at room temperature. DFT = 3.5 mils 11/22/2018

Pigmented standard formulation 11/22/2018

Pigmented system Test Results Standard 6.8 Vol% 13.3 Vol% PVC 37.5% 38.6% VOC 330.2 g/l 312.0 g/l 300.4 g/l Viscosity , 25°C 110 K.U. 98 K.U. 93 K.U. Sprayable vol. solids 62.2% 64.3% 65.7% Hardness 6H 3H Dry Adhesion 2B 4B Direct Impact 15 20 22 11/22/2018

Abrasion resistance Taber abrasion resistance is negatively impacted by the addition of XU19108.00 Tests run on clear coats cured for 14 days at 25°C with Ancamide 2353 with and without the toughening agent at 10 vol% loading ASTM D4060, 1000 g weight The unmodified sample lost 66.1mg per 1000 cycles The modified sample lost 108.1mg per 1000 cycles 11/22/2018

Effect on Gel and cure times Ancamine 1618 Minimal effect on gel time Effect is that of a non-functional diluent decreases the concentration of reactive groups NC541LV Ancamide 2353 11/22/2018

Significant Adhesion Improvement 5.5% modification Ancamide 2353 cured 11/22/2018

difference in corrosion Salt Spray Results There is no apparent difference in corrosion resistance between the standard and the modified system ASTM B117, 1000 hours on cold rolled steel Ancamide 2050 cured 11/22/2018

Outline Self assembled toughening technology background Example Application Area #1: M&PC Coatings Example Application Area #2: Powder Coatings 11/22/2018

Pipe Coating Formulation 14.5 vol% 6.9 vol% 11/22/2018

Pipe Coating Testing Formulations were dip applied 8”x1”x3/8” sand blasted bars 4 point bend at sub-ambient temperatures instron test frame number of hard cracks recorded Glass transition temperatures measured from free films 11/22/2018

Test Results 11/22/2018

Low Temperature 4 point bend performance 11/22/2018

Conclusions Self assembled second phase toughening agents improved impact resistance improved adhesion without negatively affecting viscosity or Tg 11/22/2018