effective foam control in metalworking coolants & industrial...

Effective Foam Control in Effective Foam Control in Metalworking Coolants & Industrial Metalworking Coolants & Industrial

FluidsFluids

Advantages of 3D Organo-Modified Siloxane Defoamers

Mary TaylorMünzing

KSTLE October 2, 2008

22

Presentation OverviewPresentation OverviewWhat is FoamWhy Control is necessaryMechanisms of Foam

StabilizationDe-Stabilization

Defoamer CompositionChoosing and Testing DefoamersAdvantages of 3D Organo-Modified Siloxane Defoamers

33

What isWhat is foam?foam?Basics

Simply StatedFoam is a (stable) dispersion of gas phase in a liquid system

(The Fundamentals)

44

Why is foam a problem?Why is foam a problem?The specifics are different for every industry

Use/Applications defectsMetalworking – insufficient lubricationPCB- Insufficient cleaningWood Preservatives- insufficient penetration into lumber

ProductionInsufficient fill of containersReduced speedVacuum and pump problems

SafetyTank overflow

55

Why is foam a problem?Why is foam a problem?

66

Foam StabilizationFoam StabilizationCohesive strength

pure water surfactant system

77

Foam StabilizationFoam Stabilization

Electrostatic RepulsionSurface ViscosityGibbs ElasticityMarangoni Effect

88

Foam StabilizationFoam StabilizationElectrostatic repulsion

-When the cell wall of foam drains, the two air-liquid interfacesapproach. -Electrostatic repulsion from the adsorbed and orientedsurfactant prevents further drainage and cell rupture is prevented.

99

Marangoni Effect

• Stretching of the cell wall causes a surfactantdeficiency

• Unequal surface tensions • Migration of surfactant to achieve equal surface

tension restores or heals the cell wall (Marangonieffect)

Foam StabilizationFoam Stabilization

1010

Defoaming mechanismsDefoaming mechanisms

•Drainage due to gravity

•Defoamer Spreading

•Hydrophobic Dewetting

1111

Foam (De)StabilizationFoam (De)Stabilization

GAS DIFFUSION THROUGH THE LAMELLAE

DRAINAGE TO PLATEAU BORDERS

LESSERPRESSURE

GREATERPRESSURE

DRAINAGE DUE TO GRAVITY

Thinner Films

⎟⎟⎠

⎞⎜⎜⎝

⎛+=Δ

21 R1

R14γP

1212

Defoamer SpreadingDefoamer Spreading

1313

Hydrophobic DewettingHydrophobic DewettingBridge Effects

Note:The defoaming active (whether a liquid droplet or solid particle) must have the correct size

lam

ella

Defoamers break the cell wall:

•bridging-dewetting•bridging-stretching•pin-effect

1414

What is a defoamer?What is a defoamer?

Defoamers must enter the cell wall and spread

Defoamer droplets need to have the right size to rupture the cell wall

Defoamers need to be incompatible with the system

However, too incampatible will lead to defects in the final application

Thus: defoamers must have the right balance between(in)compatibility and efficiency

1515

Defoamer ComponentsDefoamer Components

Adjust of viscosity, prevent separation, fouling,

Others

Adjust emulsifiability (compatibility) of defoamers in the systemEases spreading of the defoamer at the surface

Emulsifiers

Absorb surfactant molecules and enter into lamellae double layer

Hydrophobic ingredients

Transport of active ingredients to the surface, spread on the surface and prevent formation of a surfactant‘s layer

Carriers

1616

Defoamer compositionDefoamer composition

Biocides, thickeners, protective colloids

Surfactants

Waxes, hydrophobic silica, metal soaps, paraffines, amides, polyalkylene glycols, polyurethanes

Oils, water, solvents, modified Polyethersiloxanes, Oleo-ABCs

0 – 20%

0 – 5%

5 – 10%

75 – 90%

Others

Emulsifiers

Hydrophobicingredients

Carriers

1717

The key is the The key is the ““ Active particleActive particle””

Different active particles have different persistence strengths

3D Compounds: stable dropletSPE: semi-stable dropletGlycol emulsified: semi-stable dropletSilica: very hard particleStearate: Hard particleWax: soft particleOil emulsified: unstable droplet

For some particles, the process may “destroy” the particle or break it into smaller particles that are too small to effectively defoam

Note, the 3D siloxane compound is the ONLY truly stable particle

When effective, 3D compound is most effective.

HigherPersistence

1818

-a 3-dimensional crosslink siloxane

-presence of other components increases compatibility and washability

-very stable, very good persistence

Silicone, siloxane, SPE, Silicone, siloxane, SPE, …………SILOXANE (Si + O + CH3 + …)

SiliconeSPE

(Siloxane Polyether)3D Organo Modified Siloxane

“Silicone Fluid”“Silicone Oil”“PDMS”Polydimethylsiloxane

-very specific chemical structure:

-the “bad actor”-problems with washability-very hydrophobic:

-a good defoamer-but leads to defects

(CH3)3Si-O- -Si-O- -Si(CH3)3

CH3

CH3

x

(CH3)3Si-O- -Si-O- -Si(CH3)3

CH3

CH3

x

-a silicone backbone with polyether chains either (a) grafted on side or (b) incorporated into backbone

-PEG/PPG ratio in polyether will determine compatibility (including with water)

-the water affinity portions (i.e. the polyether portions) make this material “washable”

(CH3)3Si-O- -Si-O- - -Si-O- -Si(CH3)3

CH3

CH3

x

CH3

y

O C-CH2

OCH2CH2

OH

CH3H

m

n

(CH3)3Si-O- -Si-O- - -Si-O- -Si(CH3)3

CH3

CH3

x

CH3

y

O C-CH2

OCH2CH2

OH

CH3H

m

n

1919

3D 3D OrganoOrgano--Modified Modified SiloxaneSiloxane

Performance AdvantagesHigh Efficiency

Highly Surface ActiveHigh Persistence

High Surface AreaHigh washabilityExcellent Spreading & DispersabilityHigh Compatibility

Defoamer Selection & TestingDefoamer Selection & Testing

2121

Defoamer Selection & testingDefoamer Selection & testing

Compatibility is the key to long term persistenceBalance between incompatibility & efficiency

Too compatible the carrier acts like a surfactant or oil Defoamer selection is primarily influenced by the chemistry of the Metalworking Fluid not the machining processOther influencers are water hardness & filtrationManufacturing process

2222

INOCULATION OF

CONCENTRATE

Testing Procedures

2323

Compatibility EvaluationsCompatibility Evaluations

Oiling Out of Defoamer

Rating 1-5 (1=Best No Surface Defects)

2424

PrecipitationIn

Concentrate

Compatibility Evaluations

Rating 1-5 (1=Best No PPT)

2525

Compatibility EvaluationsCompatibility Evaluations

LossOf Clarity

Rating 1-5 (1=Best No Haze)

2626

Defoamer PerformanceDefoamer PerformanceHandshake TestHandshake Test

2727

Defoamer PerformanceDefoamer PerformanceBurrell Wrist Action ShakerBurrell Wrist Action Shaker

2828

Defoamer PerformanceDefoamer PerformancePeristaltic Pump RecirculationPeristaltic Pump Recirculation

2929

Recirculation with FiltrationRecirculation with Filtration

3030

CNOMO TesterCNOMO Tester

3131

Defoamer PerformanceDefoamer Performance

Silverson Mixer

3232

Defoamer Performance

3333

Defoamer PerformanceDefoamer PerformanceFiltration RecirculationFiltration Recirculation

3434

Defoamer PerformanceDefoamer PerformanceASTM D892ASTM D892

3535

Compatibility Compatibility vs.vs. EfficiencyEfficiencyExperimental

0.0

2.0

4.0

6.0

8.0

10.0

12.0

14.0

16.0

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28

defoamer

air c

onte

nt (%

)

0

20

40

60

80

100

120

140

160

180

surf

ace

defe

cts

air content (%)

surface defects

E ( f

3636

Predicting defoamer behavior in any single metalworking fluid is difficult because of the complex interaction of multiple components.

There is no substitute for laboratory testing!

Defoamer Selection Defoamer Selection --TestingTesting

Why not let us work for you

3737

Performance Advantages Performance Advantages

Münzing 3D Organo-modified Siloxane Defomoamers Formulated for:

CompatibilityHigh Efficiency (Speed to Knock Down)High Persistence (Time of control)Dispersability & Washability

3838

Value of 3D OrganoValue of 3D Organo--Modified Modified Siloxanes & Technical SupportSiloxanes & Technical Support

Study A – Customer Submitted 5 SystemsCustom formulated 3D Organo-modified siloxane defoamer improved compatibility & efficiency over current competitive product

Customer consolidated from 3 defoamers to 1Study B-Post Add Recirculation Test

Persistence-Up to 2 X more persistent over PDMS or Oil/Wax EmulsionEfficiency-Up to 4 X reduction in additions over PDMS or Oil/Wax Emulsion

Study C-Post Add Recirculation Test Competitive SPE vs. 3D Siloxane comparison

3 Hours Recirculation at Time Zero 16.5% Improvement1 Minute off system recovery 86% improvement5 Minutes off system recovery 86% improvement

Study D-Post Add Recirculation TestCompetitive SPE vs. 3D Siloxane comparison

With 100 ppm water & filtration Minimum 40% improvement

3939

Compatibility Rating 5 Differnt Metalworking fluids

0

1

2

3

4

5

6

7

8

Semi 206 Semi C804 Semi M203 Semi 3030 Semi 500

Ratin

g 1-

15 (l

owes

t val

ue b

est)

Competitve3D Siloxane

Study A- Product Consolidation

4040


Hand Shake Data, Time to Zero

0

10

20

30

40

50

60

70


Seco

nds

Competitve 3D Siloxane

4141

Burrell Wrist Action Shaker, Time to Zero

0

10

20

30

40

50

60

70


Seco

nds

Competitve 3D Siloxane


4242

Peristaltic Recirculation Semi 206

0

200

400

600

800

1000

1200

0 5 15 30 60 120 180 240 241 245

Time, minutes

Foam

Hei

ght,

mls

Competitive control 3D Siloxane

Pump Turned Off


4343

Peristaltic Recirculation Semi C840

0

100200

300400

500

600700

800

0 5 15 30 60 120 180 240 241 245

Time, minutes

Foam

Hei

ght,

mls


Pump Turned Off


4444

Peristaltic Recirculation Semi M203

0100200300400500600700800900

0 5 15 30 60 120 180 240 241 245

Time, minutes

Foam

Hei

ght,

mls


Pump Turned Off


4545


0

200

400

600

800

1000

1200

0 5 15 30 60 120 180 240 241 245

Time, minutes

Foam

Hei

ght,

mls


Pump Turned Off


4646


0

200

400

600

800

1000

1200

0 5 15 30 60 120 180 240 241 245

Time, minutes

Foam

Hei

ght,

mls


Pump Turned Off


4747

Post Add Recirculation Tank Side Defoaming StudyFoam Height Equivalent Additions

0

500

1000

1500

2000

2500

3000

3500

3D Organo Modified Siloxane SPE Competitor Oil Wax Defoamer 10% Siliconeemulsion

Ave

rage

Foa

m H

eigh

tStudy BStudy B-- Post Add RecirculationPost Add Recirculation

High Efficiency

4848

Study BStudy B-- Post Add RecirculationPost Add RecirculationHigh Persistence

Post Add Recirculation Tank Side Defoaming Study Foam Height 1 minute after pump shut down

0

50

100

150

200

250

300

350

400

3D Organo Modified Siloxane SPE Competitor Oil Wax Defoamer 10% Siliconeemulsion

Foam

Hei

ght,

cm

4949

Average Foam Height 18 different systems After 3Hours time 0 1minute pump off 5 minutes pump off

0

100

200

300

400

500

600

700

0 1 5

Foam

Hei

ght,

ml

Study CStudy C-- Post Add Post Add RecirculationRecirculation

SPE Competitive

3D Siloxane Defaomer

5050

Foam Height after pump shutdown

0

200

400

600

800

1000

1200

DI 100ppm DI+Filter 100ppm Filter

Foam

Hei

ght,

ml

SPE Competitor

3D Siloxane

Study DStudy D-- Post Add Post Add RecirculationRecirculation

5151

Representation

Production Site

R&D or Tech. ServiceCenters

Regional Management

Headquarters

Munzing: Organization - Locations

Heilbronn, GermanyBloomfield, NJ

Clover SC

Shanghai, China

5252

Committed to Technical Committed to Technical Support and InnovationSupport and Innovation

Chemical TechnologiesOil and Fat Chemicals-

SulfonationEsterificationAmidationPhosphationChlorination

Polymer ChemicalsPolymerisationPolycondensationPolyaddition

Compounding/Formulating

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