Innovative Polyaspartic Systems for Flooring Applicationspda-europe.org/wordpress/wp-content/uploads/2019/...• Polyaspartic technology cures up to a few times faster than conventional

Innovative Polyaspartic Systems for Flooring Applications

An aliphatic 2K polyurea system which is in use like a 2K PUR system

1

Content

November 19 │Innovative Polyaspartic Systems for Flooring Applications2

Introduction

Chemistry

Available Products

• Product Properties

Polyaspartics for flooring applications

Mechanical properties cured systems

Chemical resistance cured systems

Working Time & Reactivity

Formulation & Application Hints

Summary



The unique chemistry of polyaspartic coatings is based on a reaction of an aliphatic polyisocyanate with a

polyaspartatic ester (sterically hindered aliphatic amine)

Chemistry

O

O

O

O

NR’

R’

R+

R''N C O R’'

O

O

O

O

R’

R’

NC

NH

R

O

H

Aspartic Acid Ester Aliphatic Isocyanate Aliphatic Urea Structure

Polyaspartic Resins


Product properties

Supply

Form

Equivalent

Weight

Viscosity

@ 25 °C Reactivity

% approx. g/mol mPas

Desmophen® NH 1220 100 234 90 High

Desmophen® NH 1420 100 276 1450 Moderate +

Desmophen® NH 1423 (low FADEE*) 100 274 1450 Moderate +

Desmophen® NH 1520 100 290 1400 Low

Desmophen® NH 2850 XP (co-resin) 100 208 100 Moderate

* Fumaric acid diethylester (FADEE) content < 0,1 wt.-%

Vis

cosity

NH

1220

NH

2850

XP

NH 1420

NH 1423NH

1520

Reactivity

Aliphatic polyisocyanate cross-linkers


Product properties

Supply

Form

Equivalent

Weight

Viscosity

@ 25 °C Reactivity

% approx. g/mol mPas

Desmodur® ultra N 3600 100 183 1200 Moderate +

Desmodur® N 3900 100 179 730 Moderate

Desmodur® XP 2840 100 183 500 Moderate

Desmodur® XP 2860 100 215 500 Moderate -

Desmodur® E 2863 XP 100 380 1350 Low

Vis

cosity

Reactivity

N

3600N

3900

XP

2840

XP

2860

E2863

XP

Y = isocyanurate or

more elastic structure

OCNN

N

N

O

OO

NCO

NCO

Y



Shore hardness & Elongation

By varying the ratio of the aliphatic polyisocyanates

and polyaspartic resins the mechanical properties of

the coatings system can be fine-tuned

Properties of cured systems

20

30

40

50

60

70

80

90

100

Desmodur N3900

Desmodur XP2840

Desmodur XP2860

Desmodur 2860XP/E 2863 XP

(1:3)

Desmodur E2863XP

Sh

ore

Un

it

Shore A Shore D

230 %

<10% <10% <10%

300 %

A Comp. based on WKHB 502/ Resin: NH1420/ NH 2850 XP (7:3)


November 19 │Innovative Polyaspartic Systeme im Bereich Boden-beschichtung 7

Chemical resistance of cured systems

80 80

74

64

75 76

53

40

76 77

66

61

76 76

62 63

72 73

55

0

76 75

60 61

0

10

20

30

40

50

60

70

80

90

Demodur N3900 Demodur XP 2840 Desmodur XP 2860 DesmodurXP2860/E2863XP

(1:3) (Shore A)

Sh

ore

hard

ness

Shore D Hardness

Start value storaged in break fluidstoraged in HCl (10%) storaged in NaOH (10%)storaged in Skydrol Storaged in deion. H2O

A Comp. based on WKHB 502/ Resin: NH 1420/ NH 2850XP (7:3)

The Polyisocyanate (B Comp.) Desmodur N3900

and XP 2840 have the best chemical resistance.

In general have hard system a better resistance in

comparison to flexible Polyaspartic systems

• The tested samples were stored in the chemical medium

for 7 days. Before the test, the samples were dried in the

air at RT for 1 hour.

November 19 │Innovative Polyaspartic Systeme im Bereich Boden-beschichtung 8

Chemical resistance of cured systems


5 5 5

227

5 5 5 05 5 5

238

5 5 5

200

5 5 5 05 5 5

193

0

50

100

150

200

250


(1:3)

Elo

ng

ati

on

[%

]

Elongation at break

Start value storaged in break fluidstoraged in HCl (10%) storaged in NaOH (10%)storaged in Skydrol Storaged in deion. H2O

45

49

34

7

3431

10

0

30

43

23

6

40 40

22

5

41

35

23

5

35 34

15

50

10

20

30

40

50

60


(1:3)

Ten

sile

str

en

gth

[N/m

m²]

Tensile strength

Start value storaged in break fluid storaged in HCl (10%)

storaged in NaOH (10%) storaged in Skydrol Storaged in deion. H2O

A Comp. based on WKHB 502/ Resin: NH1420/ NH 2850 XP (7:3)

Application of Polyaspartics for Flooring Systems


Pot life & Drying Time versus Working Time & Walk-over Time

Past/ Laboratory

Potlife

Drying time

Working time

Walk-on time

Present/ on construction



Working time1 [min]

The reactivity/ working time depends on the selection

of the polyisocyanate

In general a polyisocyanate with a higher NCO

content reacts faster than a polyisocyanate with a

lower NCO content

Reactivity

0

10

20

30

40

50

60

N3900 XP 2840 XP 2860 E2863XP

1 A Comp. based on WKHB 502 but with different

isocyanate as hardener, application by hand with roller



Working time @23°C / 50%H Walk-on time @23°C / 50%H

Working time & Walk-on time

0 10 20 30 40

N3900

XP 2840

XP 2860

Blend 1

Time in min.

Blend 1: Desmodur XP 2860 / E 2863 XP (1:3)

0 100 200 300

N3900

XP 2840

XP 2860

Blend 1

Time in min.

A Comp. based on WKHB 502 but with different

isocyanate as hardener, application by hand with roller



Viscosity in mPas

A higher water content in the resin accelerates the

reaction working time is shorter

CO2 (water + polyisocyanate) formation has no

chance to form bubbles in the coating, due to the fast

curing time

Humidity has an influence on the curing time (walk-

on time), but it has no influence on the working time

Influence of water in the resin on reactivity

0

10000

20000

30000

40000

50000

60000

70000

80000

90000

100000

0 10 20 30 40 50 60

Time in min.

0,50 % 0,30 % 0,10 % 0,065 % 0,045 %* *

* Originally water content of the resin NH 1420 crosslinked with Desmodur N3900



Working time* of blend 1 Walk on time* of blend 1

Influence of air conditions - humidity and temperature

0 5 10 15 20 25 30 35

10°C / 30 % H

10°C / 80 % H

23°C / 50 % H

38°C / 80 % H

Time in min.

0 50 100 150 200 250 300 350 400

10°C / 30 % H

10°C / 80 % H

23°C / 50 % H

38°C / 80 % H

Time in min.

*A Comp. based on WKHB 502, application by hand with roller Blend 1: Desmodur XP 2860 / E 2863 XP (1:3)

Formulation hints


1. Vacuum during the paint manufacturing

Put comp. A at least 20 min under vacuum ≤ 200mPa

2. Use of molecular sieve powder

Add 2+% of a 4Å molecular sieve powder to comp. A

(best: Sylosiv A4)

3. Use of oxazolidine

Add a certain amount of oxazolidine (e.g. Incozol) to

comp. A (ongoing work)

→ working time increased by 5 min


→ adds turbidity


→ increased VOC emissions

Influence of water – How to get rid of water

Preference: 1 < 2 < 3

Possible combinations: 1 + 2 or 1 + 3

Formulation Hints


Over-indexing can increase pot life and working time

for each 20% increase in cross-linking the working time is increased by 5 - 10 minutes

curing time is also effected up to 24 hours curing time at higher over-indexing levels

Optimal cross-linking ratio is 110 – 120 %

Less effect on curing time

Best mechanical performance

< 100% reduced mechanical properties and lower chemical resistance

110-120% preferred ratio due to best overall performance

> 130% reduced mechanical properties

Important note: Cross linking ratios of ≥150 % are covered by patents in some countries, e.g. USA

Over-indexing to increase working time

0

10.000

20.000

30.000

40.000

50.000

60.000

70.000

80.000

90.000

100.000

0 10 20 30 40 50

Vis

co

sit

yin

mP

a*s

Time in min.

80% 100% 110% 120% 140% 160%

Formulation hints


Influence of cross-linking index on reactivity

Desmophen NH 1420 / 2850 XP (7:3) cross-linked

with Desmodur XP 2860

By increasing the cross-linking index the

working time is prolonged

Over-indexing to increase working time



PAS technology is a 2K technology

Same basic rules as for other 2K systems apply

Recommended mixing procedure

1. Homogenize the components prior to the mixing

2. Always blend comp. B (polyisocyanate) into

comp. A (amine part)

3. After mixing refill into a neutral container and mix

again to avoid that non-mixed material is applied

Recommended total mixing time:

180 sec (120 sec + 60 sec)

4. Mixing tools: Standard 2K mixing equipment

Application Tools & Mixing Procedure



Pasquick® system for a parking deck coatings

1st day 08:00 Surface preparation

Primer/ base coat with chips

(Pasquick)

11:00 1st top coat

(Pasquick)

14:00 2nd top coat

(Pasquick)

18:00 Return to service

Standard system for a parking deck coatings

1st day: Surface preparation

Primer/ base coat with chips

(2C EP or MCU PU)

2nd day: 1st top coat

(2C PU with solvents)

3rd day: 2nd top coat

(2C PU with solvents)

4th day: Return to service

Benefits of Polyaspartic Floor Coatings



Fast cure at ambient temperature

• Faster painting process and return to service

• Polyaspartic technology cures up to a few times faster

than conventional floor coating systems

Ideal for both interior and exterior applications.

Robust and easy application with standard

equipment

Durability and chemical resistance are on the

high level of aliphatic 2K-PUR topcoats

AgBB confirmed products (indoor air quality test)

Polyaspartics are also used in several other

application areas

• Corrosion protection, Wind Energy, Industrial Coatings

and Car Refinish

Summary


Forward-looking statements

This presentation may contain forward-looking statements based on current assumptions and forecasts made

by Covestro AG.

Various known and unknown risks, uncertainties and other factors could lead

to material differences between the actual future results, financial situation, development or performance of the

company and the estimates given here.

These factors include those discussed in Covestro’s public reports, which are available on the Covestro

website at www.covestro.com.

The company assumes no liability whatsoever to update these forward-looking statements or to adjust them to

future events or developments.

http://www.covestro.com/

November 19 21

Thank you for your attention

[email protected]

Documents

Innovative Polyaspartic Systems for Flooring Applicationspda-europe.org/wordpress/wp-content/uploads/2019/...• Polyaspartic technology cures up to a few times faster than conventional