Challenges for

Methacrylate Monomers for

Low VOC Coatings

John Wey / Gerold Schmitt

Page | 2

1) High Solid Monomers for Reduction of Resin Viscosity

2) Methacrylic LACE (Long Alkyl Chain Ester) Monomers for the Formulation of Solvent Based Coating Resins

3) Oxidative Crosslinking VISIOMER®

MUMA (Multiple Unsaturated Methacrylates)

4) Adhesion Promotion Using Wet Adhesion Monomer VISIOMER® MEEU

Page | 3

150 ± 30

50

0,20

0,50

98,00

IBOMA

250 ± 25

50

0,20

0,50

98,5

IBOA

50 ± 5ppmstabilization

HQME

max.colour

0,10%max.water content

0,01%max.acid content

98,00%min. purity

cHMASpecification

O

O

O

O

O

O

Bulky Side Chain Methacrylic

Monomers

Page | 4

Influence of High Solid

Methacrylates on Resin Viscosity

Solution polymerization in BuAc @ 140°C

Mn ~ 2000-3000 g/mol

75% solid content

Brookfield viscosity @ 23°C, Sp II

020

2530

IBOMA

cHMA

109000

101000

68000

60000

109000

98000

87000

53000

0

20000

40000

60000

80000

100000

resin viscosity [mPas]

high solids monomer [wt%]

bulky side chain

monomers are used

for the synthesis of

high solids resins

because they

significantly reduce

the resin viscosity

Page | 5

MIBK

BuAc

Xylol

IBOMAcHMA

15

4

29

21

4

41

increase of

solid content

[%]

increase of

solvent

polarity

high solids monomer

The solvent

polarity

influences the

increase of the

solid content

with the

individual high

solid monomers

Increase of Solid Content by Incorporation of

High Solid Methacrylates

Page | 6

Low Tg Resin compositions using

LACE Monomers

• 10% MMA and 20% BA in the comparative

sample were replaced by 30% LACE

monomers

• Polymerization was performed in Solvesso

100 / BuAc = 2:1 at 144°C with 75% solid

content

• OH content ~ 142 [mg KOH / g]

acid content ~ 16.5 [mg KOH / g]

Mn ~ 2200 g / mol

PD ~ 2.5

10MMA

30-LACE

33GMAA

1010TMCHMA

4040HEA

1010EHMA

727BA

with LACE

monomer

without LACE

monomer

[wt % of monomer in solid resin]

Page | 7

Properties of Crosslinked Films

versus Resin Tg

-6

5

16

-25 -20 -15 -10 -5 0 5 10 15 20

C17,4-MA

C13-MA

non

Temp. [°C]

Tg (resin polymer)

198

197

202

171

148

137

110120130140150160170180190200210

pendulum hardness [sec]

IPDI crosslinking HDI crosslinking

linear LACE monomers render a film

hardness depending on the resin glass

transition temperature

Page | 8

Solvent Resistance of Resins

Containing LACE-Monomers

linear LACE monomers with

longer side chains resist

better against automotive

fluids and organic solvents

60

80

100

120

140

160

180

200

non C13-MA C17,4-MA

pendulum hardness

break fluid diesel oil

2-propanol methyl ethyl ketone

original hardness value

Page | 9

Oxidative Crosslinking

VISIOMER® MUMA

VISIOMER® MUMA

Oxidative crosslinking

Oxidative

crosslinking

Emulsion O2

CrosslinkingO

O

X-linkable Copolymerization

O

O

X-linkable

Need for

improvement� film formation at low temperature

� improved film properties through post-crosslinking

VOC reduction

Page | 10

Pure Acrylic System

� chemical & mechanical properties improvement via cross-

linking

� improvement of open time

Improvement of Alkyds

� compatibility improvement in alkyd-acrylic blends and hybrids

� enhanced weathering resistance

� improvement of open time

Emulsion polymers

(exemplary, amounts in wt%)

GMAA

1

1

1

5

BuA

50

47

45

43

MUMA MMA

5 44

10 42

15 39

20 32

VISIOMER® MUMA Incorporated into

Emulsion Polymers

VISIOMER® MUMA

O

O

X-linkable

Page | 11

Benefits of VISIOMER® MUMA

• Superior chemical resistance

• Formulation without the use of solvents

• Improved film properties through oxidative crosslinking

• Crosslinking is accelerated by drying agents

0 1 2 3 4 5

commercial PU-

modified alkyd

dispersion

VISIOMER®

MUMA-ctg.

dispersionNivea

HOAc

EtOH

NH3

poor good

Furniture Test

(DIN 68861-1)

Improved resistance

compared to PU-modified

alkyd dispersion

Page | 12

Benefits of VISIOMER® MUMA

• Increased block temperature

⇒⇒⇒⇒ improved dirt pick-up resistance

• Good (wet) adhesion

• Excellent adhesion to old alkyd paints

• Good compatibility with alkyds

• Excellent weathering resistance

Adhesion of VISIOMER®

MUMA on alkyd paints

Cross hatch with and without

adhesive tape excellent

Adhesion on aluminium

Cross hatch with and without

adhesive tape good

w /o ta p e

w ith ta p e

0 1 2 3 4 5

Cross hatch

(DIN EN ISO 2409)

Page | 13

Wet Adhesion Monomer

VISIOMER® MEEU

N NHO

O

O

stabilization

colour

water content

Methyl methacrylate

content

N-(2-Methacryloyl

oxyethyl)ethylene urea

content

Specification

500 ± 100 ppm HQME

max. 100 ppm

Phenothiazine

max. 250

max. 1,0 %

73 ± 5 %

25 ± 3 %

VISIOMER® MEEU 25 M

stabilization

colour

water content

Methyl methacrylate

content

reactive ester content

800 ± 100 ppm HQME

max. 200 ppm

Phenothiazine

max. 500

50 ± 2,5 %

max. 5 %

50 ± 2,5 %

VISIOMER® MEEU 50 W

Page | 14

VISIOMER® MEEU

N NHO

O

O

VISIOMER® MEEU

penetrating

moisture

new paint layer

hydrophilic

interlayer

aged paint layer

How does it work:

� adhesion of emulsion coatings to

the substrate is deteriorated

under moisture contact

� consequence: blisters and

cracks

⇒⇒⇒⇒ VISIOMER® MEEU provides

excellent adhesion

Advantages:

� excellent wet adhesion and

increased wet scrub resistance

� low concentrations required (0,5

– 3 % by weight of the binder)

� easy incorporation into the

binder

Typical Application:

� emulsion coatings for exterior

applications and humidic

conditions

Page | 15

Further Information Available….

please visit us

at booth 1244