Physical sciences | EnginEEring
Research and development
of polyurea pavement marking
paint
Thi Bich Thuy Nguyen1*, Ngoc Ly Le1, Hong Chuyen Pham1, Van Tai Do2,
Hai Ninh Tran3, Dang Khoa Nguyen4
1University of Transport Technology
2Institute of Transport Science and Technology
3Hanoi University of Science and Technology
4Vietnam Institute for Building Science and Technology
Received 8 May 2017; accepted 31 August 2017
Abstract:
paints contain two components that are
Pavement markings make an important contribution to the safety of people
and vehicles on roads. Many types of pavement marking materials have been
used, and most recently, polyurea materials have been used as a binder in
pavement marking paint. This type of paint has high retro-reflection and
durability, so it has been widely applied for use at airports and on highways
around the world. This article introduces the results of our research and the
new materials recently applied to the
transport sector. Polyurea paints have
several features, like two-component-
modified polyurethane paints; polyurea
coating is a unique coating technology,
which is unlike polyurethane coating [3].
making of polyurea pavement marking paint using the formula: binder/harder
ratio (1.3/1 by weight), 42% of pigment and filler, 10% of reflective balls,
rheological additive, and dispersive additive to create outstanding features
(retro-reflection > 260 mcd/m2/lux).
Two-component polyurea coatings
are applied using specialized spray
equipment that provides high-pressure
application, fast drying time, and an
Keywords: pavement marking material, polyurea, retroreflection.
Classification number: 2.3
achievement of optimal adhesion. The
fast drying feature is contained within a
wide temperature range and is unaffected
by moisture. A fast drying time of paint
Introduction
Outlined reflective traffic guides
serve an important role in controlling the
flow of traffic. The painted lines on roads
include centerline stripes, lane dividing
lines, and marked areas due to obstacles,
parking areas, road signs, and walkways.
The standards of these marking materials
consider their durability, dry time, and
alkyd paints become brittle and lead to
decreased adhesion on road surfaces,
as well as developing glass particles in
the paint. Besides that, solvent signal
reflective paint also contains volatile
organic compounds (VOC) that are not
suitable for traditional usage, transport,
and removal methods.
Reflective marking paints based on
leads to time to put the product into
use more quickly. Polyurea coatings
have color stability, abrasion resistance,
and good adhesion to all surfaces. In
particular, polyurea reflective marking
paints have high reflectiveness and
are sustainable over time. Polyurea
materials claim to have a lifespan of up
to five years [4, 5].
their impact on the environment [1, 2].
thermoplastics
are
also
being
widely
Despite their appearance in many
Currently in Vietnam, solvent
reflective marking paints based on alkyd
resins or styrene acrylic are usually
used in the transport sector. It has been
found that signal reflective paints based
on alkyd resins and solvents provide
better visibility for pedestrians, both
during the day and at night, compared to
signal reflective paints that are based on
used today on express ways, highways,
and airplane runways. For highways,
roads, and airplane runways, the
abrasion resistance and reflectiveness
of these coatings are still having many
shortcomings, resulting in increasing
maintenance and repair costs, being
inefficient, and not ensuring traffic
safety [1, 2].
countries, polyurea coatings have
yet to be applied broadly in Vietnam,
particularly in the field of transportation.
In this study, with an aim of mastering
the technology and initial identification
of polyurea coating applications in
the conditions of Vietnam, marking
materials based on polyurea elastomer
have been studied on a selection of basic
thermosetting plastics. Under oxidation,
Polyurea
elastomer-based
marking
components
including:
curing
agent
*Corresponding author: Email: thuygiaothong@gmail.com
December 2017 Vol.59 Number 4
Vietnam Journal of Science,
Technology and Engineering
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Physical sciences | EnginEEring
ratio, filler content, dispersing additives,
Results and discussions
components is varied from 2:1 to 3:1 by
rheology additives, and loading of glass
bead.
Materials and experiment
Resin/curing agent
Based on a published document and
standards prescribed about polyurea
volume;
- Loading of pigments, filler powder
is greater than 15% by weight;
Materials
- The binder is Bayer NDT1-
Desmophen® (amine number 190 mg
KOH/g, viscosity at 25°C: 1,000 mPa.s,
marking materials, the specifications for
polyurea marking paints are chosen as
follows [3-5]:
- Paints having 100% solid content;
- Using amino resin NDT1 and
isocyanate Desmodur VP LS 2371
to making polyurea coatings. The
components are blended according to
the density at 20°C: 1.06 g/ml);
- A mixing ratio between A and B
the formula in Table 1.
- The curing agent is polyisocyanate
Desmodur VP LS 2371 (Bayer -
Table 1. Polyurea marking paint components.
Germany);
% by weight
- Titanium oxide pigment, yellow
organic pigment, calcium carbonate, and
Sample 01
Sample 02
Sample 03
talc fillers (China);
A component
-
Dispersing
additives
including
NDT1
30
37
45
dispersants, DP-1 of BYK (solution
of copolymers with acid groups, acid
TiO2
15
15
12
number: 53 mg KOH/g, specific weight:
Filler
27
20
17
1.03 g/ml, concentration of volatile
substance: 52%);
- Dispersing additives including
dispersants, DP-2 of Cognis
Rheology agent FS-1
Dispersing agent DP-1
B component
1
1
1
1
1
1
(neutralization of acid salts polycarbonic
Desmodur VP LS 2371
28
28
28
with polyamines, the density: 0.88 to
0.90 g/cm3, acid number: 50 mg KOH/g);
Table 2. Drying time, adhesion, and abration of coating films.
- Rheological additives including
rheological additives FS 1 (compound
Properties
Drying time (min)
Adhesion (MPa)
Abration (g)
of
hydrophilic
silica
surface
of
the
Sample 01
5
3.5
0.08
carrier Aerosi, specific surface: 200
m2/g, average particle size: 12 nm, SiO2
content: 99%);
Sample 02
Sample 03
8
12
3.0
4.0
0.07
0.06
- Rheological additives, FS
Elements (organic derivatives
2
of
Table 3. Paint with differences in titanium oxide content.
hectorite clay, fine
weight: 1.8 g/cm3);
powder,
specific
% by weight
- The glass bead, DPI Class
according to AASHTO M247.
I,
A component
Sample 01
Sample 02
Sample 03
Experiment
NDT1
37
37
37
Thedetermination of paint properties
TiO2
7
13
18
is according to the following tests: KU
Filler
28
22
17
viscosity, smoothness, luminosity,
impact resistance, oil resistance, salt
resistance, alkali resistance, retro-
Rheology agent FS-1
Dispersing agent DP-1
1
1
1
1
1
1
reflectivity, and abrasion. The testing
B component
methods are specified in ISO standard
8787: 2011.
Desmodur VP LS 2371
28
28
28
22
Vietnam Journal of Science,
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Physical sciences | EnginEEring
Then, prototyping and testing the
properties of coating film including the
drying time (minutes), the abrasion (g),
and the adhesion (MPa). The results are
shown in the Table 2.
90
80
70
60
60
76
80
From the obtained results, the ratio
50
1.3/1 of A/B is chosen to carry out the
next survey.
40
30
Effect of pigments on properties of
paint
20
10
The brightness of road markings
has major influence on the ability to
recognize road markings of driving.
0
7
13
18
Typically, the rutile titanium oxide
powder was used with the aim to
Fig. 1. Effect of TiO2 content on the paint brightness.
increase the brightness of the paint. With
amine compound NDT1 and isocyanate
Table 4. Formula of polyurea yellow paint.
curing agent, the paints were conducted
with titanium oxide content changing 7,
% by weight
13, and 18% by weight (Table 3).
A component
After fabricating the prototypes, the
brightness of the paint was measured
NDT1
37
(Fig. 1). The results showed that the
brightness of the coating increases
when the content of titanium oxide is
TiO2
Yellow pigment
8
5
increased. Specifically observed was
the brightness of the paint at 60% with
Filler
22
7% by weight of titanium oxide, further
Rheology agent FS-1
1
increased to 13 and 18% by weight at the
brightness of 76 and 80%, respectively.
Dispersing agent DP-1
1
The chosen content of titanium oxide in
white paint polyurea was at least 13% by
B component
weight. Polyurea yellow paint is made
Desmodur VP LS 2371
28
with the following formula (Table 4):
The measured brightness of marking
paint is 55% in accordance with standard
Table 5. Effects of additives on properties of paint.
yellow marking paint.
Dispersing agent
Appearance
Fineness (µm)
Effect of additives on properties of
paint
DP-1
Homogeneous. Normal surface
25
The effect of dispersing additives
DP-2
A few small cracks appeared
30
signed DP-1 and DP-2 on the properties
of paints having the same content of
Table 6. Properties of marking paint having rheology agent.
1.0% by weight is shown in Table 5.
The results from Table 5 show that
Anti-deposition aadditives
Flow ability
State
using
dispersing
agent
DP-1
makes
better dispersion of pigment powder and
filler than that of DP-2.
FS-1
Non flow
Non deposition
The effect of rheology agent FS-1
FS-2
Flow
Slight deposition
and FS-2 on the properties of marking
paints having the same content of 1.0%
Not rheological additives
Flow
Deposition
by weight is shown in Table 6.
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Brightness, %