New Development of

Multifunctional Coalescent for Coatings

Laura J. Kovach, Emerald Kalama Chemical

CTT Conference, September 2019

Agenda

• Background

• Experimental Approaches & Protocol

• Test Results

• Secondary Benefits

• Conclusions & Next Steps

Journey to Reduced VOC Levels

• Drive to reduce VOC’s has resulted in a

series of incremental changes and innovations.

– Solvent to water

– Changes in resins

– Changes in coalescent types and levels used

– Changes in other additives

• Resulting technical performance trade-off’s

• New approaches to optimizing results continue to be developed.

1970’s

EPA targets

coatings

1990

Clean Air

Act

Amendment

1999

VOC levels &

progressive

reduction

targets

implemented

2004

Selective

HAPS

listings &

exemptions

2008

SCAQMD

implements

strictest VOC

limits,

emissions

fees

2014

OTC lowers

VOC levels,

lags

SCAQMD

4

Balancing Performance Needs

• Many believe coatings must

have a “10” ranking on

all criteria (unwilling to

compromise).

• While there is willingness to

sacrifice some properties,

which combination of

properties?

• Block resistance ranked

among highest needs

– Related to surface tack

– May also manifest as issues

with hardness development,

print, and dirt pick up.* Chemquest Market Study

Room for Improvement vs. Incumbent Solutions

Major US coating

companies feel there

is significant room

for improvement

in anti-blocking.

* Chemquest Market Study

Highly unsatisfied Highly satisfied

A

B

C

D

E

F

G

Approaches to Improved Hardness/Block

• Harder conventional resins:

required more coalescents (VOC considerations)

• Core-shell resins:

limits on addition for effectiveness, potential soft spots

• Self-crosslinking resins: economic considerations

• Other additives:

– Fluorinated Surfactants – economics, foam considerations

– Wax Additives – less permanence, recoat considerations

– Filler – surface appearance considerations

• New Developments: multifunctional coalescent

– Equal to improved efficiency to typical coalescents

– Increases hardness development

– Improves hot blocking

– Enhances robustness of preservation package (in-can)

Protocol – Coatings Modifier

• Binders

– Styrene acrylic, +44Tg

– 100% acrylic, +29Tg

– VAE, +6Tg

• Formulations

– Flat: 45 PVC

– Semigloss: 14 PVC

• Coalescents (formulated to 4.4°C MFFT)

– TMPDMIB

– TEGDO

– Commercial dibenzoate

– Experimental 1

– Experimental 2

• Flow/Leveling

• Burnish

• Hardness

• LTC

• Block

• Viscosity

• Contrast Ratio

• Gloss

• Dirt Pickup

• Print Resistance

• Scrub

• Washability

• Adhesion

• Dry Time

• Mudcracking

• Open Time

• Wet Edge

• Sag

• VOC

• Freeze/Thaw

• Heat Stability

• In-Can Stability

Testing

Coalescent Efficiency: Acrylic

* VOC’s calculated based on ASTM D6886 test method results

Sample% to

Binder% in

Formulation

VOC Add to Formula*

(Exclude Water, g/L)

Gloss -60°

TMPDMIB 3.2% 2.0% 39 39

TEGDO 3.6% 2.2% 0.2 43

Commercial

Dibenzoate4.0% 2.5% 6.4 42

Experimental 1 2.5% 1.5% 18 37

Experimental 2 3.2% 2.0% 14 40

Acrylic (Tg~29°C)

Required Amount for 4.4°C MFFT, PVC 14 (semi-gloss)

Coalescent Efficiency: Styrene-Acrylic

Styrene-Acrylic (Tg ~44°C)

Required Amount for 4.4°C MFFT, PVC 14

* VOC’s calculated based on ASTM D6886 test method results

Sample% to

Binder% in

Formulation

VOC Add to Formula*

(Exclude Water, g/L)

Gloss -60°

TMPDMIB 8.6% 5.3% 103 28

TEGDO 7.0% 4.3% 0.4 21

Commercial

Dibenzoate9.7% 5.9% 15 29

Experimental 1 7.9% 4.8% 57 18

Experimental 2 8.6% 5.3% 37 24

Coalescent Efficiency: VAE

VAE (Tg ~6°C)

Required Amount for 4.4°C MFFT, PVC 14

* VOC’s calculated based on ASTM D6886 test method results

Sample% to

Binder% in

Formulation

VOC Add to Formula*

(Exclude Water, g/L)

Gloss -60°

TMPDMIB 0.5 0.3% 5.9 42

TEGDO 0.5 0.3% 0.02 44

Commercial

Dibenzoate0.5 0.3% 0.8 39

Experimental 1 0.5 0.3% 3.5 41

Experimental 2 0.5 0.3% 2.1 43

Hardness (ASTM D4366A):Styrene-Acrylic

Hardness (ASTM D4366A): Acrylic

Block Resistance (ASTM D4946) -Styrenated Acrylic

E E E E E E

Block Resistance (ASTM D4946) -Acrylic

E E E E E EE E

* TMPDMIB, Commercial DB, and Experimental 2 were not tested

Block Resistance (ASTM D4946) -VAE

E E E E E E E E

Dirt Pickup Resistance

E E E E E E

VOC-ASTM D6886

Industry Challenge

Properly preserved water-based coatings have a better overall carbon footprint than alternatives studied.*

Responding to “no preservative” positions

Relative Cradle-to-Grave LCA results of different preservative

scenarios in architectural coatings

(water-based coating normalized

to 100% for each indicator)

* “Life Cycle Assessment of Architectural

Coatings: Considering Different

Preservations Scenarios.” ACA. Journal of

Coatings Technology. August 2018.

A Hot Topic

• Combinations of Antimicrobials (Lanxess, Eastern Coatings Show 2019)

– BIT and pyrithiones; OIT and pyrithiones

– Activated halogen compounds (i.e. DBDCB) and reduced levels of MIT/CIT

• Upgraded Antimicrobials

– Encapsulation encapsulated diuron (Lonza, European Coatings Conf. 2019)

– Copper compounds and combinations with ZPT or BIT (Corning, ECS 2019)

• Hurdle Technology

– Improved plant hygiene

– Higher pH (>10.5), concern for corrosive label

– Dry powder

– Boosters: EDTA, AMP, Li Salts, amine and chlorine compounds (Paul Wood, consultant, ECC 2019)

– Wollastonite fillers (Imerys, ECC 2019)

– Copper compounds and combinations with ZPT or BIT (Corning, ECS 2019)

– Binders and rheology modifiers (Dow, ECC 2019)

– New multifunctional coalescents (Emerald Kalama Chemical)

Many short- and long-term approaches at conferences in 2019

Day 0:

InoculateDay 1 Day 2 Day 3 Day 5 Day 7

EP Bacteria Requirement

:

3 Log Reduction

EP Yeast/Mold Requirement:

No Increase from 14 days

Test Protocol: ASTM D2574 – “In-Can” Coatings

Complete

kill

Round “X”

Gram Negative Bacteria: Pseudomonas aeruginosa, Enterobacter aerogenes

Procedure: Coatings are inoculated to an in-can concentration of

107 cfu/g (inoculum was 109 cfu/g) for each organism. Continue

inoculations until coating fails complete kill on day 7.

ASTM D2574 Challenge TestingAcrylic paint, 45 ppm BIT + varying multifunctional coalescent

ASTM Rating

0 = No bacterial recovery

1 = 1-9 colonies

2 = 10-99 colonies

3 = >100 distinct colonies

4 = TNTC

Experimental multifunctional coalescent #1 has secondary benefit to improve robustness of the traditional preservative in paint. This challenge test is for

demonstration purposes and would NOT be indicative of the types of conditions encountered in actual industrial, commercial use.

■ Negative Control

■ 3.0% Experimental 1

VOC, excl. water,

ASTM D-2369,

calculated

<1 g/l

Conclusions

• Coalescent results show equal to improved efficiency to

reduce MFFT and LTC performance.

• Experimentals show promising results to improve hardness

and hot block even over traditional high VOC coalescents.

• Unexpected results in enhancing formulation robustness.

• Further work planned in deep base systems and other resin

systems.

Disclaimer

DISCLAIMER

The information contained herein is believed to be reliable, however is based upon laboratory work with

small scale equipment and does not necessarily indicate end-product performance. Because of variations in

methods, conditions and equipment used commercially in processing these materials, Emerald makes no

representations, warranties or guarantees, express or implied, as to the suitability of the products for

particular applications, including those disclosed, or the results to be obtained. Full-scale testing and end-

product performance are the responsibility of the user. Emerald Performance Materials shall not be liable for

and the customer assumes all risk and liability for use and handling of any materials beyond Emerald’s direct

control. Nothing contained herein is to be considered as permission, recommendation nor as inducement to

practice any patented invention without permission of the patent owner.

THANK YOU

Brad Farrell

Brian Morehouse

Emily McBride

Jenna Blankenship

Julie Vaughn

Kyle Posselt

Sarah Strother

Shikha Gupta

Stephen Foster

Thank you!

Questions?

Laura.Kovach@EmeraldMaterials.com

Appendix: Test Methods

• pH: ASTM E70 – The pH of the coatings was measured using a Beckman 310 pH meter with general purpose electrode.

The coatings were pH adjusted to within 8.5 to 9.5 pH using ammonium hydroxide (28%).

• Stormer Viscosity: ASTM D562 – Initial Stormer viscosity was measured using a Brookfield KU-2 viscometer with

paddle geometry. Rheology modifier was added to adjust initial viscosity to within the range of 90 – 105 KU.

• ICI Viscosity: ASTM D4287

• MFFT: ASTM D2354 – Minimum film formation temperature was evaluated using a Gardco MFFT Bar 90 instrument.

Polymer latex emulsions blended with nonionic surfactant and coalescent were drawn down using an MFFT draw down

applicator and film formation was evaluated after one hour. The temperature gradient setting on the instrument was -5° C

to 13° C. The film formation temperature was evaluated visually, and the temperature measured using a separate

temperature probe.

• Low Temperature Coalescence (LTC): Paint and equipment were conditioned at 40°F for 2 hours. Paint was drawn

down on a Leneta Form HK to 6 mils wet. The films were dried horizontal at 40° F for 24 hours and rated (lab rating 10=

excellent, 0= very poor).

• Scrubbability: ASTM D2486 – Coatings were applied using a 7 mil Dow applicator bar to a Leneta P121-10N chart and

dried at 23° C at 50% RH for 7 days. The scrubbability was measured using a Gardco D10 Washability and Weartester. A

10 mil shim was employed with abrasive media (SC-2). Initial failure was recorded, and complete failure defined as a

continuous thin line across the shim.

• Block Resistance: ASTM D4946 – Coatings were applied using a 3 mil bird film applicator to a Leneta form WB chart

and dried in an environmentally controlled room at 23° C and 50% relative humidity for seven days. Samples were

constructed from 1.5 inch squares and oriented coating surface to coating surface with a 1 kg weight placed upon a

number 8 stopper at ambient temperature or 120° F for thirty minutes. The samples were then allowed to equilibrate at

room temperature for 30 minutes and were then evaluated through “blind” testing to remove bias.

• Gloss: ASTM D523 – Coatings were applied using a 3 mil bird film applicator to a Leneta form WB chart and dried in an

environmentally controlled room at 23° C and 50% relative humidity for seven days. Gloss measurements were

conducted in triplicate using a Gardco micro-Tri-gloss meter model 4446.

Appendix: Test Methods

• Heat Stability: ASTM D1849 – Tested at 120°F for two weeks. Initial and final viscosities taken.

• Flow and Leveling: ASTM D4062 – Leneta test blade used to apply paint. Dried paint was then rated.

• Hardness/Hardness Development: ASTM D4366A – Coatings were applied using a 3 mil bird film applicator to

aluminum A36 Q panels and dried in an environmentally controlled room at 23° C and 50% relative humidity. Hardness

was measured using a Gardco Koenig and/or Persoz Hardness Rocker with the respective pendulums for each test.

Hardness values were reported as the average of three measurements.

• Freeze/Thaw Stability: ASTM D2243 – Frozen at 0°C and thawed at ambient. 3 cycles used.

• Washability: the paint samples were drawn down on a Leneta P121-10N scrub chart using a 7 mil Dow blade. The

panels were then allowed to dry in a horizontal position for 7 days. Stains were applied to each panel in a 1 inch wide

area, with a 0.25 inch space left between stains. Stains tested included: Lip stick (Rimmel, Rosseto #510, red), crayon

(Crayola, red), ketchup (Hunts Tomato Ketchup, no preservatives), mustard (French’s Classic Yellow prepared mustard

packets, pencil (Papermate Micrado Classic HB#2), coffee (Safeway Signature Select: Sun Kissed Blonde), food Coloring

(McCormick Food Color & Egg Dye, green), wine (Gnarly Head Wines, old vine zinfandel, 2016 Lodi zinfandel), permanent

marker (Sharpie Magnum, black), ball point pen (Papermate Flexgrip Ultra 0.8F, black), and washable marker (Mr. Sketch,

blue). A Kim wipe was used to apply coffee, wine and food coloring by placing the dry Kim wipe on the panel and

saturating it with stain. The stains were left for 1 hour, after which any excess was removed. A C-31 sponge with 10 g

409 multipurpose-lemon was used to wash panel with 50 cycles. Permanent market, washable marker, and ballpoint pen

stains were washed separately to avoid bleeding. The panel was then rinsed, blotted dry and allowed to thoroughly dry in

a horizontal position overnight. The Delta E of stained area vs. white, unwashed area was measured using a colorimeter.

A visual assessment was also performed.

• Dirt Pick Up: The paint sample was applied by 3 mil drawdown on an aluminum Q36 panel. The panel was allowed to

dry in a horizontal position for 7 days. The top half of the panel was covered up and the synthetic dirt was spread evenly

over the uncovered portion. The panel was placed in a 50° C oven for 30 minutes. The panels were removed from the

oven and the loose dirt was removed by tapping on the panel. The top portion of the panel was uncovered. The % Y

reflectance of the tested part and the untested part were read.

• Burnish Resistance: ASTM D6736.

Appendix: Test Methods

Test Reference/method

Dry Adhesion ASTM D3359B – Paint was applied to dried aged alkyd with a brush

and dried for 7 days before testing by cross hatch tape adhesion.

Drying Time ASTM D1640 – 3 mil wet film applied to Leneta 3B, set to touch

determined at ambient.

Mudcracking Paint was applied with a Leneta Antisag meter (14-60 mils) on an HK

chart at ambient and 40°F. After 24 hours dry the greatest mils

without cracking noted.

Print Resistance ASTM D2064

Sag Resistance ASTM D4400

Touch Up Touch up was tested with the paint prepared for the color

acceptance. Self-primed Upsom was used and applied with a Linzer

2”Bristle and polyester brush at RT and 40°F and allowed to dry

overnight. The test paint was applied and rated for sheen uniformity

and color difference.

Appendix:CEH Surface Coatings, 2005