PAINT FORMULATION AND LATEX SELECTION TO ELIMINATE

ARKEMA COATING RESINS

PAINT FORMULATION AND LATEX SELECTION TO ELIMINATE SURFACTANT LEACHING IN LOW VOC PAINTS

NEAL ROGERS, SENIOR PRODUCT

DEVELOPMENT ENGINEER


AGENDA

Understanding Surfactant Leaching

Methods to Analyze Surfactant Leaching

● Application Testing

● Analytical Testing

Levers to Pull in Latex Development

Paint Formulation Aspects

Performance Data

UNDERSTANDING SURFACTANT STAINING

Low VOC coatings formulated with

common acrylic latexes are prone to

surfactant staining when applied to

exterior buildings

Painting in low temperature / high

humidity environmental conditions

tends to promote surfactant leaching

A resin technology solution in

combination with proper formulating

strategies are needed to eliminate the

defect

Surfactant staining defect

may be pronounced soon

after painting as shown in

these examples.


Pacific Northwest climate is particularly

welcoming for surfactant leaching

Low Temps < 45°F combined with rel.

humidity > 70% are favorable conditions

for leachate migration

Sources:

https://www.usclimatedata.com/climate/seattle/washington/united-states/uswa0395

https://weather-and-climate.com/average-monthly-Humidity-perc,seattle,United-States-of-America


Staining comes from leachate that migrates outward from an applied

coating system to wet environment

Leachates may include a wide variety of hydrophilic materials found

in a fully formulated coating

● Surfactants: alcohol ethoxylates, polyethylene glycols

● Excess salts

● Biocide and fungicides

Because colorant pigment dispersions contain concentrated amounts

of surfactants, dark tinted paints are more susceptible than white or

light color paints

APPLICATION TESTING TO ASSESS SURFACTANT STAINING

Water droplet test

● Described in ASTM D7190-10: Standard Practice to Evaluate Leaching

of Water-Soluble Materials from Latex Paint Films

● Place water droplets on paint film drawdown at various stages of

drying

● Allow the water to stand for 10 minutes, then tilt up the test panel to

allow the water to run-off

● Once dry, evaluate the runoff area for visible streaking defect

APPLICATION - SURFACTANT LEACHING TESTING

Surfactant leaching (D 7190-05 (2015))

● Phenomenon simulated: visible water streaking with

obvious gloss or color difference, or both

7 Days 1 Day 4 Hours

Rating: 1 ~ 5

Exudate extraction test

● Drawdown test panel is prepared and the weight of dry

coating film is determined prior to testing

● There are several ways to force the exudation. One

variation is to submerge a pre-weighed coated test

panel in water for 1 hour

● Test panel is removed and allowed to dry.

● Test panel is re-weighed to determine % leachate

extracted from the film.

GRAVIMETRIC METHOD

SURFACTANT MIGRATION IN LATEX FILMS HAS BEEN

CHARACTERIZED

In simple systems, surfactant leaching can be easily characterized

● Acrylic latex using sulfonate as polymerization surfactant

● Combination of Atomic Force Microscopy (AFM) and X-Ray

Photoelectron Spectroscopy (XPS) proven to be powerful approach to identifying surfactant enriched on surface

Latex film

surface

Same film

surface

after water

rinse

0.0

1.0

2.0

3.0

4.0

5.0

Surface beforerinse

Surface after rinse Bulk

Na

or S

, %Na

S

HOW DO WE USE THIS APPROACH TO SOLVE A PROBLEM WHERE THE COMPONENTS OF THE SYSTEM ARE NOT WELL KNOWN?

Two commercial paints: “Paint A” and “Paint B”

● Paint A shows less leaching than Paint B in the field

• Confirmed by gravimetric method and physical inspection in our lab

● Qualitative method does not reveal source of leachate and formulations not

completely known.

Paint B

Paint A

Leachates

under

optical

microscope

FILM POROSITY & WATER VAPOR PERMEABILITY OF PAINTS

Paint ID Paint A Paint B

Void area – digital image analysis 11% 23%

WVP (perms) – ASTM D1653 19.0 ± 2.2 29.1 ± 3.2

Paint A Paint B

APPROACH TO DETERMINING NATURE AND SOURCE OF THE

LEACHATE

Chemical analyses of leachates

● Analyses of Inorganics

• Trace metals by Inductively Coupled Plasma-Mass Spectrometry (ICP-MS)

● Analyses of Organics

• Functional groups by FTIR and NMR

• Separation and identification by Liquid chromatography-ElectroSpray Ionization Mass Spectrometry (LC-ESI-MS)

● Components Analyzed:

• Paint A:

- Whole paint, paint serum, dry leachate

• Paint B:

- Whole paint, paint serum, paint base serum, dry leachate

- Latex serum

QUANTITATIVE ANALYSIS OF INORGANIC LEACHATES OF

PAINTS

From ICP it was determined:

• Paint A (better performing) has higher concentration of cations in serum but lower concentration in leachate than paint B, i.e., lower percentage leaching of different cations

• Paint B has much higher concentration of Sodium ions in paint and serum

• Paint A is rich in Potassium salts but lower amounts detected in leachate

From other techniques we determined:

• Paint B has a more complex mixture of organics in the leachate including complex mix of alcohol ethoxylates, biocides and fungicides etc.

General Conclusions

• Consistent with porosity measurements

• Sodium seems to be an issue, other inorganics perhaps not so important

Elements (ppm)

K P Na Total Cations

Serum Paint A 1200 416 631 2598

Paint B 402 ND 1200 1712

Leachate Paint A 511 10 391 945

Paint B 245 ND 842 1103

ICP-MS analysis

of spun-down serum

and dry leachate

SOURCE OF THE SODIUM AND ORGANICS IDENTIFIED IN

“PAINT B” LEACHATE

Na

BIT

Anionic Surfactant

Low MW PEG

alcoholEthoxylate

Biocide/Fungicide/Algeacide

Other unknownwater-solublecompounds

Latex Paint

alcoholethoxylates

alcohol Ethoxylates

Reducing surface leaching requires a holistic approach

Latex modification

Paint reformulation

Analysis of

Serum from paint,

paint base, and

latex

WHAT WERE THE RESULTS AND WHAT WE LEARNED

Latex & Paint Design● Latex designed to improve film

formation and reduce sources

materials contributing to leaching.

● Latex film formation optimized with morphology & particle size.

● Paint formulated to reduce leachate.

Key learnings● A combination of analytical techniques

definitively identified the chemical

origins of leachate

● Deep technical understanding enabled collaborative problem solving

Before After


NEW SURFACTANT LEACHING RESISTANT INTERIOR/EXTERIOR ACRYLIC

PAINT PERFORMANCE

ARKEMA HAS DEVELOPED A NEW LATEX TO OPTIMIZE

SURFACTANT LEACHING RESISTANCE

100% Acrylic binder for Interior and Exterior Coatings

Properties

Property Typical Value

Total Solids % 52

Weight per Gallon 8.8

pH 8.5

Viscosity, cps <800

Particle Size, μm 0.15

MFFT, °C 16

NEW LATEX PERFORMANCE HAS BEEN EVALUATED ACROSS

A NUMBER OF FORMULATIONS

The next few slides feature a comparison of binders that include those targeting general exterior or masonry applications, featuring a satin or

general semi-gloss and gloss formulations.

MFFT °C % Solids

New Latex 16 52

Masonry Acrylic 1 16 58

Masonry Acrylic 2 12 58

Gloss Acrylic 1 <5 49

Gloss Acrylic 2 24 45

Gloss Acrylic 3 <5 45

NEW LATEX PERFORMANCE: SATIN DEEP BASE

Satin Deep Base Formulation

Tinted with individual low-VOC colorants at 12 fl oz/gal

0

0.5

1

1.5

2

2.5

3

3.5

4

Masonry Acrylic 1 ENCOR 601

% L

ea

cha

te E

xtra

cte

d

Satin Deep Base Surfactant Leaching

Blue Red Green Untinted

• 70% Reduction

in extracted

leachate for an

untinted deep

base

• 40% Reduction

in extracted

leachate when

tinted

SA

TIN

Be

st P

erf

orm

an

ce

New Latex

NEW LATEX PERFORMANCE: SATIN MID BASE

New Latex offers excellent potential for block resistance, scrub resistance and efflorescence resistance

0

1

2

3

4

5

6

7

8

9

10

Masonry Acrylic 1 Masonry Acrylic 2 ENCOR 601

Satin Mid Base - Brown Tint

Block Resistance

Block Resistance Room Temp

Block Resistance 120F

New Latex0

200

400

600

800

1000

1200

1400

Masonry Acrylic

1

Masonry Acrylic

2

ENCOR 601


Scrub Resistance

0

2

4

6

8

10

12

14

16

Masonry Acrylic 1 Masonry Acrylic 2 ENCOR 601

DE

Co

lor

Ch

an

ge

aft

er

Exp

osu

re


Efflorescence Resistance

24 Hr DE 7 Day DE

SA

TIN

New LatexNew Latex

NEW LATEX PERFORMANCE: GLOSS WHITE

The new technology may also be formulated in semi-gloss to high

gloss coatings and maintain excellent performance balance

for block resistance and surfactant leaching

0

1

2

3

4

5

6

7

8

9

10

Gloss Acrylic 1 Gloss Acrylic 2 Gloss Acrylic 3 ENCOR 601

Gloss White Block Resistance

Overnight Block RT Overnight Block 120F

50 55 60 65 70 75 80 85 90

Gloss Acrylic 1

Gloss Acrylic 2

Gloss Acrylic 3

ENCOR 601

Gloss @ 60 deg

0

1

2

3

4

5

Water Drop (0-5, 5 = no visible

leaching)

% Leachate 1 Hr Soak

Gloss White Surfactant Leaching

Gloss Acrylic 1 Gloss Acrylic 2 Gloss Acrylic 3 ENCOR 601

Be

st P

erf

orm

an

ce

Be

st P

erf

orm

an

ce

GLO

SS

New Latex

New Latex

New Latex

NEW LATEX PERFORMANCE: SEMI-GLOSS DEEP BASE

0

5

10

15

20

25

30

Gloss Acrylic 1 Masonry Acrylic 1 ENCOR 601

Semi-Gloss Deep Tint:

Konig Hardness, 7 Day Dry

No Tint Dark Blue

0

1

2

3

4

5

6

7

8

9

10



Block Resistance, Overnight Dry

Room Temp, No Tint Room Temp, Dark Blue 120F, No Tint 120F, Dark Blue

New latex matches performance of Acrylic binder technology engineered for

deep tint hardness and block resistance while offering greatly improved

surfactant leaching and water resistance.

Se

mi-

Glo

ss

New LatexNew Latex

NEW LATEX PERFORMANCE: SEMI-GLOSS DEEP BASE

New latex matches performance of Acrylic binder technology

engineered for deep tint hardness and block resistance while

offering greatly improved surfactant leaching and water

resistance.

0

1

2

3

4

5

6

7



% Leachate Extracted, 1-Hour Soak

No Tint Dark Blue

Se

mi-

Glo

ss

Be

st P

erf

orm

an

ce

New Latex

FORMULATION STUDY FOR SURFACTANT

LEACHING RESISTANCE

ARKEMA IS ACTIVELY STUDYING KEY RAW MATERIAL SELECTION DRIVERS TO OPTIMIZE PERFORMANCE FOR SURFACTANT LEACHING

Current formulation studies focus on dispersant and

associative thickener choice

Comparing Results at 2 PVC levels

● 20%

● 50%

Dispersant Rheology – HEUR Chemistry

A Hydrophilic KU driver #1 + ICI driver #1

B Hydrophobic #1 KU driver #2 + ICI driver #2

C Hydrophobic #2 Thickener #3

NEW LATEX FORMULATION PARAMETERS

Held TiO2 and Extender type

constant to focus on impacts

to Dispersant/Rheology

modifier choice

Different Coalescent levels

were tested for the different

formulations

● 20 PVC at 4.6% on resin solids

● 50 PVC at 2.5% on resin solids

20 PVC 50 PVC

WPG 10.7 11.7

# TiO2 / 100 Gal 219 245

# Extender / 100 Gal 22 282

% PVC 20 50

% Vol Solids 43 38

SCRUBS AND BLOCK: 20 PVC FORMULA

0

1

2

3

4

5

6

7

8

9

10

A/A A/B A/C B/A B/B B/C C/A C/B C/C

Dispersant/Rheology Combination

Block Resistance: 20% PVC Formulas

Block Room Temp Block Elevated Temp

0%

20%

40%

60%

80%

100%

120%


3000 Scrubs


Scrubs: 20% PVC Formulas

All samples performed well for 1-Day dry time block resistance.

Dispersants A and C were slightly better overall than Dispersant B.

Scrubs was best for sample A/A followed by B/A and B/C.

SURFACTANT LEACHING: 20 PVC FORMULA

All samples rated 4 or 5 for surfactant leaching after overnight dry using water drop test method ASTM D7190.

Formulations using more hydrophobic dispersants B and C showed

lower leachate than dispersant A.

0.0%

0.2%

0.4%

0.6%

0.8%

1.0%

1.2%

1.4%



Collected Leachate, 1-Hr Water Soak:

20% PVC

SURFACTANT LEACHING: 50 PVC FORMULA

Samples made from Dispersant C rated best – 4 or 5 ratings –for surfactant leaching after overnight dry using ASTM D7190.

Dispersants A and B gave 2 and 3 ratings.

Formulations using more hydrophobic dispersants B and C showed lower leachate than dispersant A.

0.0%

0.2%

0.4%

0.6%

0.8%

1.0%

1.2%

1.4%

1.6%

1.8%



Collected Leachate, 1-Hr Water Soak:

50% PVC


ADDITIONAL BASELINE

PERFORMANCE STUDIES

NEW LATEX - FLAT TO SEMI-GLOSS

Study Formulations: VOC <10g/L

Exterior Flat White & Deep Base

Exterior Semi-gloss White & Deep Base

• White base tested with standard Universal colorant

(2oz/Gal) & hydrophilic dispersant

• Deep base tested with low-VOC Universal colorant

(12oz/Gal) & hydrophobic dispersant

FLA

TS

em

i-

Glo

ss

ADHESION

NEW LATEX – EXTERIOR FLAT DEEP BASE – AGED GLOSS

ALKYD ADHESION

New Latex provides wet adhesion to alkyd after 4

hour dry. 100% of the coating remaining after cross

hatching and 500 scrub cycles.

FLA

T

Wet Adhesion

over GA (4hr dry) A1 A4 A6

A7 New

Latex

C1 -

Contractor

C2 -

Contractor C3 - DIY C4 -

Standard

C5 -

Standard

C6 -

Standard

C7

Standard

C8 -

Masonry

% remaining after

scrub:0 100 0 100 100 0 100 100 100 100 100 0

Scrubs at Initial

Failure1 >500 1 >500 >500 1 >500 >500 >500 >500 >500 1

Scrubs at Final

Failure3 >500 1 >500 >500 3 >500 >500 >500 >500 >500 2

A1 – Good value acrylic

A4 – High-performance interior/exterior acrylic

A6 – General-purpose acrylic

A7 – New Latex

C – Commercial Paints

NEW LATEX – EXTERIOR FLAT DEEP BASE

CHALKY ALKYD ADHESION

FLA

T

C2 C3New Latex C1 C4 C5

Commercial Flat Deep Base Paints

A4 A5A1 A3 A6Commercial Binder in Lab Paints

New Latex provides excellent 24 hour wet and dry

chalk adhesion.

NEW LATEX – EXTERIOR SEMI-GLOSS WHITE BASE – AGED

GLOSS ALKYD ADHESION

New Latex provides wet adhesion to alkyd after 4 hour dry. 100% of the coating remaining after cross hatching and 500 scrub cycles.

Se

mi-

Glo

ss

Wet Adhesion over GA

(4hr dry) A1 A4 A5 A6

A7 New

Latex

C1 -

Contractor

C2 -

Contractor C3 - DIY

% remaining after scrub: 0 100 100 0 100 100 100 100

Scrubs at Initial Failure 1 >500 >500 1 >500 >500 >500 >500

Scrubs at Final Failure 10 >500 >500 9 >500 >500 >500 >500

A1 – Good value acrylic

A4 – High-performance interior/exterior acrylic

A5 – Self-crosslinking APE-free acrylic

A6 – Legacy general-purpose acrylic

A7 – New Latex

C – Commercial Paints

Exterior Semi-gloss White Base

PVC 20%, VS 40%

Se

mi-

Glo

ss

New LatexL2 A3 A5

Commercial Acrylics in Semi-Gloss FormulationA4 A6

New Latex provides excellent 24 hour wet and dry

chalk adhesion.

Dry

Tape

Pull

Wet

Tape

Pull


PVC 20%, VS 40%

NEW LATEX – EXTERIOR SEMI-GLOSS WHITE BASE – AGED

CHALKY ALKYD ADHESION

ACCELERATED

DIRT PICK-UP RESISTANCE

ACR’S ACCELERATED DPR CYCLIC TESTING

Samples prepared on aluminum panels, dried overnight

Panels exposed in QUV for 100 hours

Iron oxide slurry drawn down over portion of panel, allowed to sit for a standard two hours

Panels scrubbed with wet sponges for 30 cycles

Excess iron oxide rinsed off under running water

Panels allowed to dry for two hours

Y% brightness readings taken from both sponge paths, averaged.

Staining cycle repeated two more times, recording Y% brightness.

Cyclic DPR testing done to better simulate long-term DPR of coating.

FLA

T

New

Latex

CYLIC ACCELERATED DPR SHOWS GREAT LONG TERM

PERFORMANCE OF NEW LATEX

Exterior Flat White Base

PVC 40%, VS 40%



Se

mi-

Glo

ss

New Latex


PVC 20%, VS 40%



L2A1 A3 A4 A5 A6 A7

New Latex

C2

Photos show enhanced dirt pickup resistance

performance for new latex.


PVC 20%, VS 40%

ACCELERATED

EFFLORESCENCE RESISTANCE

ACR’S ACCELERATED EFFLORESCENCE TEST

Fiber-cement composite board coated with high pH mortar, allowed to dry overnight.

Two coats of tinted test paint applied to sections of the mortar, allowed to dry overnight

Panels placed in Cleveland Humidity cabinet set at 50ºC for 48 hours.

Remove panels and place on a cool surface. Rate the panels for efflorescence on a scale from 0-5, with 5 equal to no efflorescence, 0 equals complete failure

NEW LATEX OUTPERFORMS MANY OF THE FORMULATED

COMMERCIAL PAINTS FOR EFFLORESCENCE RESISTANCE

FLA

T

0.0

0.5

1.0

1.5

2.0

2.5

3.0

3.5

4.0

4.5

5.0

A1 L2 A3

A4

A5

A6

A7

EN

CO

R 6

01

X8

C1

- C

on

tra

cto

r

C2

- C

on

tra

cto

r

C3

- D

IY

C4

- S

tan

da

rd

C5

- S

tan

da

rd

C6

- S

tan

da

rd

C7

- R

ece

nt

C8

- M

aso

nry

Flat Deep Accelerated Efflorescence Resistance (48Hr)

Be

stP

erf

orm

an

ce

Ne

w L

ate

x

FLA

T

NEW LATEX OUTPERFORMS MANY OF THE FORMULATED

COMMERCIAL PAINTS FOR EFFLORESCENCE RESISTANCE

New

Latex

Paint #7

BLOCK RESISTANCESemi-Gloss

NEW LATEX SHOWS ROBUST BLOCK RESISTANCE POTENTIAL

Se

mi-

Glo

ss

New

Latex


PVC 20%, VS 40%

SUMMARY

New Arkema resin technology enables architectural coatings formulators to construct low surfactant leaching coating systems.

Polymer and paint manufacturers can work together to define the source of surfactant leaching.

● Focus on reducing all free hydrophilic species in end formulation.

● Latex morphology and structure must enable optimum tight film formation.

Delivers excellent water resistance capabilities balanced with strong block resistance, hardness, and film toughness for interior and exterior coatings.

A strong binder choice for

● Zero and low VOC exterior masonry coatings

● Commercial building re-paint needs

● Interior semi-gloss tint base coatings with robust water resistance

RECOGNITION

Many Arkema colleagues contributed in preparing the contents of this presentation. Especially the following:

Doug Mall

Jeff Schneider

Christine Fortener

Dr. Wenjun Wu

Thank you!

[email protected]

Documents

PAINT FORMULATION AND LATEX SELECTION TO ELIMINATE