In-mold coatings for SMC, thermoplastics and low

temperature thermoset composite processes European Coatings Conference

Functional Coatings

Berlin, Germany

5-6June2012

Elliott J. Straus

OMNOVA Solutions Inc.

2990 Gilchrist Rd.

Akron, Ohio 44305

USA

Presentation Outline

• Part I IMC functionality and

application to SMC

• Part II IMC application to

thermoplastics and low

temperature composites

• Part III

Summary & questions

In-Mold Coatings Technology – Compression Molding

• In-Mold Coatings improve the

quality of SMC parts

• Growing use of IMC as a primer

for basecoat paint

• Economic incentive to replace paint

operations with conductive and color

matched IMC’s

• Next logical step to use IMC itself

as an appearance coating

GenGlaze® and Stylecoat® In-Mold Coatings

EC-610, EC-2447, EC-2500

(Conductive Black)

EC-800

(Conductive Gray

20 Gray

(Non-Conductive)

50 Gray

(Non-Conductive) Stylecoat® Red

(Appearance IMC)

Stylecoat® Green

(Appearance IMC)

SMC Manufacturing Process

Film

Film

Wind up Roll

Compaction Rolls

Resin

Resin

Chopper

Chopped Fibers

Cut and weigh

SMC charge

Charge

the Mold

SMC

Filling

SMC

Curing

IMC

Injection

IMC

Curing

Filling

Open the Mold Remove the

Molded Part

SMC Cycle IMC Cycle Pre-Molding Post-Molding

Unit Operations in Compression Molding

Sheet Molding Compound with IMC

IMC Process for Compression Molded SMC

Stationary Mold Half

Moveable Mold Half

Stationary Mold Half

Moveable Mold Half

Stationary Mold Half

Moveable Mold Half

IMC

SMC

In-Mold Coatings Technology – Compression Molding

IMC Key Performance Features

• One component design with catalysis by the addition of peroxide

initiator away from the press

• Excellent rate of property development at typical molding temperatures

• High conductivity in primer IMC at coating thicknesses as low as 0.5

mil (12.7 microns)

• Excellent strength, abrasion and scuff resistance for ease of handling

and sanding in subsequent processing

• Appearance UV resistant clear/pigmented coating available

• Excellent substrate adhesion

• 100% Solids

In-Mold Coatings Technology – SMC Compression Molding

• Substrate porosity filling and surface sealer

• Provides solvent/moisture barrier

• Provides a uniform and improved surface

– reduces or eliminates fiber read through

– no orange peel

– levels low and high spots

– enhances DOI

• Facilitates good primer/paint adhesion

• Provides the option of a “primerless” scenario

• Product available with specialized functions

– conductivity

– color matched primer & clear/color topcoat

– Soft touch

IMC Functionality

IMC Application Equipment

Common SMC Parts Utilizing GenGlaze® IMC

Storage

Door Transition

Panel

A-Pillar

D-Pillar

Hood

Sunvisor Cab Door

Fender

Rooftop

Gravelometer 0°F

GM9508P

Cross-Hatch

Ford Bl 106-01

Tape Adhesion

GM9071P

Brittleness

GM9506P

CDL4.0 (no chipping)

MT2C after

10 Day Water Immersion

Ford ESB-M2P124-A1

MT1A After

E-Coat

1 Hour @ 400°F

IMC performance and Overall part quality Acceptable part

• Summer Months

• Storage conditions

• Humidity effect on

SMC/IMC

• Temperature Control

• Cooling bands on

drums

• Housekeeping

• Monitoring press operation

• Force

• Velocity

• parallelism

• Phase timing

• IMC open/reclose speed

• IMC open height

• IMC booking

• Shot size adjustment

• SMC/IMC cure times

• IMC film thickness

Selection of Process parameters

• SMC charge placement

• SMC molding profile

• IMC molding profile

• IMC shot size based on part surface area

• Rationale for adjustments

•Troubleshooting guide

IMC Meter

• Properly sized

• Check valve leak

• (2) Synchronized

• Injection rate

Press

• Force profile

• Velocity profile

• Parallelism

• Machine time

• Operational performance

Mold

• Position in Press Bed

• Temperature control

• Shear edge condition

• Nozzle placement/Flush

• Condition of mold in general

• Vacuum effectiveness & process

• Part lifting

IMC

• Catalyst level

• Age/History

• Temperature

• Shot volume

• Storage

• Mixing schedule

• SMC pattern cut

• SMC pattern placement

• Good molding practices

•Cleaning

•Discipline

• Training status

• Shift change communication

Environment Measurement Method

Machine Equipment Material Human

IMC Process Troubleshooting

SMC

• Viscosity consistency

• Sheet weight

• Cure behavior

• Release

•Enhances DOI

•No orange peel

•Provides a solvent/moisture barrier

•Abrasion and scuff resistance

•Provides a conductive surface for electrostatic painting

•100% solids (zero VOC’s)

Key Points to Remember

In-Mold Coatings for SMC

Presentation Outline

• Part I IMC functionality and

application to SMC

• Part II IMC application to

thermoplastics and low

temperature composites

• Part III

Summary & questions

Injection

Molding Primer Top Coat

Emission Emission Current Process

Thermoplastic Pellets Finished Product

Injection

Molding Top Coat

Emission

IMC

Short term solution (no primer)

Thermoplastic Pellets Finished Product

Injection

Molding

Long term solution (no primer and paint)

Thermoplastic Pellets Finished Product

IMC for Thermoplastic

Thermoplastic

Injection

Packing

Solidification by Cooling

Packing

Coating Curing Reaction

IMC

Filling

Eject Part

IMC for Thermoplastic in Injection Molding

Injection Molding with IMC process

Key Issues in IMC Process

• Nozzle location

– 100% coverage is achieved

– Location is cosmetically acceptable

– Easy maintenance

– Defects like trapped air are minimized

• Coating Injection Pressure

– Should not exceed the clamping pressure of the Injection Molding Machine to avoid leakage

– Mold design to prevent IMC leakage from parting line

• Coating material curing conditions

– Adhesion and compatibility with particular thermoplastic molding conditions and mold thermal design

– Peroxide selection and amount yields adequate pot life of IMC

Summary of low temperature IMC primer @ 100ºF (38ºC) potlife

Catalyzed and placed in Oven @530

Hour of Day

% peroxides 630 730 930 1000 1030 1100 1115 1315

1.75/1.0 ok ok gel Solid Solid Solid Solid Solid

1.75/0.75 ok ok ok Solid Solid Solid Solid Solid

1.75/0.5 ok ok ok gel Solid Solid Solid Solid

1.75/0.25 ok ok ok ok ok ok gel Solid

1.75/0.1 ok ok ok ok ok ok ok gel

1 hour 2 hours 4 hours 4.5 hours 5 hours 5.5 hours 5.75 hours 8.25 hours

IMC for SMC and Thermoplastic – Tooling Difference

shear edge acts as a seal

SMC mold

Opening will lead to

coating leakage

Thermoplastic

mold

The Thinner Groove of the Valve Cover

Study on the IMC Filling in a Valve Cover Part

IMC Injection Port

Comparisons of the Short Shots and Numerical Predictions

IMC Nozzle Experimental Mold

Predicting Fill Patterns

• IMC Fill simulation tool developed based on Hele-Shaw model to predict Fill patterns

32

Pressure Comparison for PCABS

(Full Shot)

Comparison of the Short Shots and Numerical Predictions

Heavy Truck Bumper

• The Priamus data collection device used for determining the optimum injection process and in place to monitor the IMC injection pressure from the IMC injection device for future trial/production process control.

• IMC 13in3 shot volume target

•Thermoplastic PC/ABS

•Cincinnati Milacron 4500 Ton Press

•dual injection cart with 9000psi peak injection pressure

capability

•Mold temperature 180°F target (actual range 165°-180°F)

•PRIAMUS data collection device used to optimize process

Presentation Outline

• Part I IMC functionality and

application to SMC

• Part II IMC application to

thermoplastics and low

temperature composites

• Part III

Summary & questions

Summary of Applications Available IMC for various applications

IMC Chemistry Substrates Temperature Application Functionality

GenGlaze® Primers

epoxy acrylate SMC BMC LCM

150ºC

Automotive

Heavy Truck

Marine

Conductive primers

non-conductive primers

epoxy/urethane

acrylate

Stylecoat® Topcoats urethane acrylate SMC BMC LCM 150ºC Residential

Topcoat

NSP® Soft Touch urethane di-acrylate SMC BMC LCM 150ºC (80ºC)

Food Service

Specialty non-slip surface

GenGlaze®/Stylecoat® with low temp peroxide package

urethane acrylate PC/ABS PET

DCPD RTM TPO 80ºC

Automotive

Heavy Truck

Agricultural

Primer or Topcoat

Development or

Approval process

Commercialized

Summary

• The absence of solvents in IMC makes it an environmentally preferred “green” process.

• Since the coatings are incorporated during the molding process instead of being applied separately they reduce the number of surface finishing steps and cost in manufacturing while being environmentally friendly.

• A newly developed family of primers and topcoats for low temperature processes allow for a broader application potential.