Novel Monomer Free Vinyl Hybrid Resin for Composite Radomes and Aerospace Applications
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Novel Monomer Free Vinyl Hybrid Resin for Composite Radomes and Aerospace Applications Jim Bono JEC Paris March 12th, 2014

Background • Advanced Material Market • Styrenated Systems are Unacceptable – Governmental Regulations – Control Technologies Needed – Minimize Capital Investment • Development Need for Reactive Diluent Free Thermoset Resin Systems – Cost Effective – Improved Dry/ Wet Tg – Improved Water Absorption – Improved Production Rates- approach 3 minute cycle

Nomenclature Styrene Free Resins Reactive Diluent Free Solids: “Pre-preg Monomer Free Hot Melt Vinyl Hybrids” Alternative Reactive Diluents Liquids: Reactive Oligomers “Vinyl Hybrid Liquid Resins” VT • Acrylates • Others

Chemistry Description: Vinyl Hybrids • ADVALITE™ – Monomer Free Hot Melts • ADVALITE™ – Vinyl Hybrid Liquid Resins

Radomes Functions • Shield microwave antenna from adverse environmental effects • Minimal effect on electrical performance • Withstand Structural Loads from pressure differential Material Property Considerations • Water Absorption: Water absorbs transmission energy and increases loss tangent – Low water absorption is necessary for radomes Dielectric Constant: Determine the ability of insulator to store electrical energy – Low dielectric constant is necessary for radomes Loss Tangent: Ratio of input/output power through material – Low loss tangent is necessary for radomes

Radome Resin Candidates • Cyanate Esters • Modified Epoxies (BisA Cyanate/Epoxy) • Epoxy (Accelerated Dicyanamide, 120° C cure) • ADVALITE™ Vinyl Hybrid

% Water Absorption Comparisons (64 Hour Boil) 3,5 3 2,5 Epoxy/DICY Modified Epoxy Cyanate Ester 1 0,5 0 Percent Water Absorption

Dielectric Constant Comparison 3,1 3 2,9 Epoxy/DICY X4833-60 (Vinyl Hybrid) Cyanate Ester

Dielectric Constant Comparisons Dry vs. Wet 3.30 Dielectric Constant X4833-60 (Vinyl Hybrid) No Preconditioning X4622-47 (Vinyl Hybrid) 24 Hrs Boiling Water X4767-47 X4759-06 (Vinyl Hybrid) (Vinyl Hybrid) 64 Hrs Boiling Water

Dissipation Factor/Loss Tangent Comparison 0,025 Epoxy/DICY X4833-60 (Vinyl Hybrid) Modified Epoxy 0,01 Cyanate Ester

Comparison of Dissipation Factor/Loss Tangent 0,050 Loss Tangent Epoxy/ DICY

ADVALITE™ X4833-60 Radome Resin Clear Cast Mechanical Properties Property Flexural Strength Flexural Modulus Tensile Strength Tensile Modulus

Hand Lay-up (Prepreg) Properties for Optimum Prepreg Optimum tack and drape Low volatile content Low temperature cure Long shelf-life Low heat of reaction Controlled flow

Hand Lay-up • Heat of reaction of ADVALITE™ Vinyl Hybrids System is roughly half of a standard 120 °C cure, accelerated Dicyanamid Bis-A epoxy, so parts with large crosssections can be cured with less risk of exotherm and cracking ADVALITE™ Vinyl Hybrid Systems offer cure times under 5 minute for rapid part production ADVALITE™ Vinyl Hybrid Systems are a peroxide-cure, lending itself well to inline mixing for rapid prepreg production Prepreg produced using ADVALITE™ VINYL HYBRIDS systems does not need to be frozen or refrigerated, lowering the cost of shipping and handling, and minimizing...

Radome Resin Typical Cost/Lb (Formulated) $100 $90 $80 $70 Cyanate Ester

ADVALITE™ 35000-00 Vinyl Hybrid FR Grade Hot Melt Prepreg Resin Prepreg Thermo-Mechanical Properties Property Tensile Strength Tensile Strength Retention Tensile Modulus Tensile Modulus Retention Compression Strength Compression Modulus Flexural Strength Flexural Strength Retention

ADVALITE™ Vinyl Hybrid Liquid Resins Vacuum Infusion Process (VIP) Critical to Filling Complex Geometries and Moldability: • Processing Conditions- resin factors to consider: • • • Polymer structure Viscosity Degree of cure-part thickness Optimize resin for low viscosity and good fiber wetting while retaining good physical properties

Vacuum Infusion Process Infusion Flow Rates Vacuum Line Peel Ply Flow Distance vs Time Record Time at Distance Increments Start Stopwatch Flow Media Inlet Line

Vinyl Hybrid Infusion Trial Thick section part- 12 mm Used to study exotherm conditions and glass wetting Glass wetting acceptable Glass wetting acceptable throughout entire composite part throughout entire composite part Deep vertical draw sections to ensure proper resin flow rates

Mechanical Properties Comparison Neat Resin Clear Cast Results ADVALITE™ Flexural Modulus Tensile Strength Tensile Modulus Water Absorption Flexural Strength

Conclusions ADVALITE™ Vinyl Hybrid Systems offer resins capable to produce both prepreg and vacuum infusion molding systems for the Aerospace market which offer the following: • Excellent retention of properties after exposure to water at elevated temperature • Superior performance to epoxy regarding; Water Absorption, Dielectric Constant and Dissipation Factor • Lower heat of reaction than epoxy for rapid cures of thick cross-section parts • No need for refrigeration of prepreg • Lower total cost for the manufacture of cost effective commercial radomes

Visit Reichhold at booth M48 – 7.3 THANK YOU FOR YOUR ATTENTION!