TECHNICAL FIELD
5 The present invention relates to the use of a polymer
resulting from the polymerization of 2-octyl aerylate and
optionally at least one other monomer as binding agent in
or for the manufacture of a coating composition.
10 BACKGROUND OF THE INVENTION
It is known to apply paints of acrylic type to surfaces,
in particular building facades, not only to embellish
them and to prevent the deposition of dirt, in particular
dust, but also in order to protect them against the
15 infiltration of rainwater. To this end, the coating must
be able to adhere suitably to the surface, deform easily
without risk of cracking and not exhibit a tacky nature.
An example of a paint composition exhibiting the
20 abovementioned compromise in properties has been
disclosed in the application EP 0 599 676. This
composition includes a polymer resulting from the
polymerization of three distinct monomers, consisting in
particular of a mixture of (meth)acrylic acid, a
25 (meth)acrylic acid ester, such as n-butyl acrylate, and a
benzophenone derivative, and optionally of a fourth
monomer which is styrene.
Another type of paint composition has been described in
30 the document US 2012/0121921. It is a flame-retardant and
water-resistant polymer composition, comprising a polymer
binder in the latex form, obtained by radical
WO 2014/207389 2 PCT/FR2014/051615
polymerization of at least one ethylenically unsaturated
monomer, comprising in particular n-butyl acrylate, and
of tert-butyl (meth)acrylate.
5 Acrylic compounds, optionally in combination with
styrene, in addition exhibit the advantage of making
possible the formulation of paints giving good resistance
to light and to weather conditions. However, they are
generally produced from propylene, which is a byproduct
10 of the refining of oil. In point of fact, oil deposits
are rapidly becoming exhausted. In order to anticipate
the supplying difficulties relating to these resources,
it would be desirable to be able to replace these acrylic
compounds with compounds obtained from carbon sources of
15 renewable origin.
In order to meet this need, provision has been made, in
the application WO 2012/084974, to use, as binder in
paints, a dispersion of two vinyl polymers including at
20 least 10% by weight of monomers of renewable origin, such
as n-butyl acrylate. It is indicated that this binder
makes it possible to obtain a flexible and nontacky paint
which dries at low temperature.
25 However, it is apparent to the applicant company that
n-butyl acrylate does not include sufficient carbon of
renewable origin and that it exhibits a more hydrophilic
nature than long-chain acrylates, such as 2-octyl
acrylate.
30
After numerous research studies, the applicant company
has demonstrated that it is possible to formulate a
composition for coating in the film form, based on
WO 2014/207389 3 PCT/FR2014/051615
polymer of predominantly renewable origin, which
composition simultaneously exhibits good mechanical
properties, in particular a suitable flexibility and a
suitable elongation and a good cohesion, and also a
5 sufficiently hydrophobic nature, using, as binder, a
homo- or copolymer based on 2-octyl acrylate.
Such a compound has already been described, in
particular, in the application WO 2012/038441, as
10 constituent of an impact modifier, and in the documents
WO 2008/046000, WO 2009/079582, WO 2009/132098 and WO
2009/129087, as constituent of a pressure-sensitive
adhesive.
In the document US 4,983,454, an acrylic resin based on
15 2-octyl acrylate and other (meth)acrylic monomers,
prepared in an aqueous solvent, is used as barrierforming
coating interposed between, on the one hand, a
metal substrate covered with a layer of paint obtained by
electrodeposition and, on the other hand, an upper layer
20 of paint. The acrylic resin exhibits a glass transition
temperature of -52CC and an elongation at break at -20°C
of 610%. This coating is presented as flexible, adhesive
and in particular capable of absorbing energy in order to
protect the composite material against impacts, this
25 composite material advantageously constituting a motor
vehicle paint.
The applicant company has now discovered that it is
possible to use 2-octyl acrylate of renewable origin to
prepare a copolymer exhibiting specific properties well
30 suited to forming a binder in coating compositions, this
coating having properties identical with those obtained
with monomers resulting from the petrochemical industry.
WO 2014/207389 4 PCT/FR2014/051615
ACCOUNT OF THE INVENTION
A subject matter of the present invention is thus the use
of a polymer resulting from the polymerization of 2-octyl
5 acrylate of renewable origin and optionally at least one
other monomer, as binding agent in or for the manufacture
of a coating composition.
DETAILED DESCRIPTION OF EMBODIMENTS
10
In this invention, provision is made to use a specific
polymer as binding agent in a coating composition.
The term "coating" is understood to mean, in the present
15 description, a layer applied to a substrate in the film
form, with a thickness generally of between 50 urn and a
few mm, starting from a binding polymer with a Tg of
between -40°C and +40°C according to Fox's law, said film
being applied in a thickness sufficient to modify the
20 appearance of the substrate, in particular its optical
properties, and/or to protect its surface, in particular
against scratches, moisture, dirt or light.
The term "coating composition" thus does not encompass
25 the adhesive compositions intended to improve the
adhesive properties of the substrate. On the other hand,
it encompasses paint, mortar, coating, varnish and ink
compositions, without this list being limiting.
30 In addition, in this description, the expression "of
between" is understood as including the limits cited and
also all the intermediate values, and the expression
WO 2014/207389 5 PCT/FR2014/051615
"ranging from ... to ..." is understood as excluding the
limits cited.
The polymer used according to the invention comprises
5 2-octyl acrylate of renewable origin.
This monomer results predominantly, indeed even
completely, from plant sources and can thus be regarded
as a material of renewable origin, which is characterized
10 by the fact that its content of 14C represents at least
50%, preferably at least 60%, for example at least 70%,
indeed even at least 80%, of that of atmospheric C02
(according to the standard ASTM D6866) . In other words,
the 2-octyl acrylate comprises at least 0.6 x 10"10% by
15 weight of 14C, with respect to the total carbon,
according to the standard ASTM D6866-06. The content of
14C can be measured according to a method of counting by
liquid scintillation and expressed in disintegrations per
minute per gram of carbon, or dpm/gC. The dpm/gC value of
20 the 2-octyl acrylate is generally at least 7.2 ±
0.1 dpm/gC.
The 2-octyl acrylate can be prepared from 2-octanol and
acrylic acid, in particular in the presence of an
25 esterification catalyst of acid type comprising sulfur,
such as methanesulfonic acid, and of at least one
polymerization inhibitor. Alternatively, it can be
prepared by a transesterification reaction between a
light acrylate, such as ethyl acrylate, and 2-octanol.
30 The 2-octanol can itself result from the treatment of
ricinoleic acid, derived from castor oil, with sodium
hydroxide, followed by a distillation in order to remove
the sebacic acid. A process for the preparation of
WO 2014/207389 6 PCT/FR2014/051615
2-octyl acrylate by direct esterification is in
particular described in the application WO 2013/064775.
The abovementioned monomer can be homopolymerized, in
5 which case the polymer used according to the invention is
a 2-octyl acrylate homopolymer. In an alternative form,
it can be copolymerized with at least one other monomer,
so that the polymer used according to the invention is a
copolymer including, advantageously, from 1% to 80% by
10 weight, preferably from 25% to 75% by weight, more
preferably from 30% to 75% by weight, indeed even from
50% to 70% by weight, of 2-octyl acrylate, with respect
to the total weight of the copolymer.
Furthermore, the use of monomers, themselves at least
15 partially of plant and/or animal origin, makes it
possible to reinforce the biobased nature of the
copolymer containing the 2-octyl acrylate.
This other monomer can in particular be chosen from:
20 vinylaromatic monomers, such as styrene; ethylenically
unsaturated nitriles, such as acrylonitrile; esters of
ethylenically unsaturated mono- and dicarboxylic acids,
such as 2-ethylhexyl acrylate, n-butyl acrylate, methyl
methacrylate and itaconic acid esters; esters of
25 monocarboxylic acid and vinyl or allyl alcohol, such as
vinyl acetate; ethylenically unsaturated mono- and
dicarboxylic and sulfonic acids, such as (meth)acrylic
acid, itaconic acid and styrenesulfonic acids; amides of
ethylenically unsaturated mono- and dicarboxylic acids,
30 such as acrylamide; N-vinyllactams, such as N-vinylpyrrolidone;
N-vinylamides; N,N~diallylamines; N,Ndiallyl-
N-alkylamines; allyl- or vinyl-substituted
nitrogenous heterocycles, such as N-vinylimidazole and
WO 2014/207389 7 PCT/FR2014/051615
vinyl- and allylpyridines; and their mixtures. Preferred
comonomers are the esters of ethylenically unsaturated
mono- and dicarboxylic acids, in particular methyl
methacrylate and n-butyl acrylate, vinylaromatic
5 monomers, more particularly styrene, and their mixtures.
Other functional or crosslinking monomers can
advantageously be added to the 2-octyl acrylate before
polymerization, for the purpose of improving the
10 properties of chemical resistance to water or to
different household products of the coating composition.
These monomers can also improve the barrier properties or
properties of resistance to the fouling of the coating
composition, or also improve the mechanical properties of
15 the polymer, such as its resistance to elongation.
Mention may nonexhaustively be made, among the
crosslinking monomers, of diacetone acrylamide in
combination with the adipic acid bishydrazide,
hydroxylated monomers in combination with
20 polyisocyanates, siloxane-comprising (meth)acrylates,
polyfunctional (meth)acrylates, that is to say
(meth)acrylates exhibiting several unsaturations, and
their mixtures. Mention may nonexhaustively be made,
among the functional monomers, of acetoxyethyl
25 (meth)acrylates, monomers carrying phosphate or
phosphonate functional group(s), monomers carrying ureido
functional group(s), monomers carrying amine functional
group(s), and their mixtures.
30 The monomers constituting the polymer used according to
the invention can be polymerized conventionally, for
example by means of a radical aqueous emulsion
polymerization. The pH of the emulsion can be buffered in
WO 2014/207389 8 PCT/FR2014/051615
order to be maintained between 4 and 7 during the
polymerization process. The choice may be made, as
radical initiators, of those conventionally used in this
type of reaction and in particular inorganic initiators,
5 such as ammonium persulfate, sodium persulfate and
potassium persulfate, alone or in combination with a
reducing agent intended to lower the polymerization
temperature, or also organic initiators, such as tertbutyl
hydroperoxide or hydrogen hydroperoxide, which are
10 activated by reducing agents. Depending on the properties
targeted, one or more chain-transfer agent(s) can be
added during the process in order to obtain the desired
distribution of molecular weights. The polymerization can
be carried out at a temperature of 0°C to 150°C,
15 preferably of 30°C to 100°C and for example of 50°C to
90°C, for a period of time of 4 to 6 hours, for example.
It can be carried out at atmospheric pressure and/or in
the presence of an inert gas. This polymerization process
results in a latex advantageously having a dry matter
20 content of between 20% and 70% by weight and preferably
between 35% and 60% by weight.
The polymer obtained generally has a glass transition
temperature (Tg), calculated by virtue of Fox's law, of
25 between -40°C and +40°C, preferably ranging from -30°C to
+30°C, more preferably of between -10°C and 10°C, indeed
even between -10°C and 0°C.
The polymer can be obtained according to a single-stage
30 process, that is to say with continuous feeding with a
single monomeric composition, or according to a multistage
process employing different monomeric compositions,
in order to obtain particles exhibiting different Tg
WO 2014/207389 9 PCT/FR2014/051615
ranges. Particles of this type are denoted by particles
of the core-shell type or structured particles. In this
case, the mean Tg of the polymers obtained on conclusion
of each stage can also be of between -40°C and +40°C and
5 preferably ranging from -30°C to +30°C.
In addition to this polymer, the coating composition used
according to the invention contains water. It can include
various additives chosen, for example, from: one or more
10 pigments; one or more pulverulent fillers; one or more pH
adjusters, in particular one or more bases making it
possible to neutralize the acid monomers optionally
copolymerized with the 2-octyl acrylate, such as an
alkali metal hydroxide (in particular sodium hydroxide),
15 aqueous ammonia or a water-soluble amine; one or more
dispersing and/or wetting agents, such as sodium
polyphosphate, potassium polyphosphate or ammonium
polyphosphate and naphthalenesulfonic acid salts; one or
more thickening agents, such as xanthan and cellulose
20 derivatives; one or more antifoaming agents; one or more
film-forming agents; one or more antifreezes; one or more
flame retardants, in particular organophosphorus
compounds, magnesium hydroxide or aluminum hydroxide; one
or more biocides; and their mixtures.
25
The pigments can in particular be chosen from: white or
colored inorganic pigments, such as titanium dioxide,
zinc oxide, barium sulfate, antimony trioxide, iron
oxides, ultramarine and carbon black; organic pigments,
30 such as azo dyes, indigo dyes and anthraquinone dyes; and
their mixtures.
WO 2014/207389 10 PCT/FR2014/051615
The pulverulent fillers can in particular be chosen from:
calcium carbonate or magnesium carbonate; silica;
silicates, such as talc, kaolin or mica; calcium sulfate;
aluminosilicates; and their mixtures. These fillers are
5 preferably employed in the finely divided form.
In addition, in particular in the case where it is used
for the manufacture of a coating, the coating composition
according to the invention can include an additional
10 binder, in particular a silicon resin or a silicate.
The different constituents of the coating composition can
be mixed in a way conventional for a person skilled in
the art, in their normal proportions. It is preferable
15 for the polymer to be added, generally in the form of an
aqueous dispersion (latex), to a dispersion or a paste of
pigments.
The polymer in the form of an aqueous dispersion
20 generally represents from 5% to 90% by weight, preferably
from 10% to 75% by weight, with respect to the total
weight of the composition. By dry weight, the polymer
generally represents from 5% to 50% by weight and
preferably from 20% to 40% by weight, with respect to the
25 total weight of the composition.
This composition can be provided in the liquid or
semisolid form.
30 It preferably has a concentration of solids of betv/een
25% and 75% by weight and preferably between 35% and 65%
by weight.
1
WO 2014/207389 11 PCT/FR2014/051615
The composition used according to the invention can be
applied to any substrate, in particular made of wood,
metal, glass, cement, paper, textile, leather, plastic or
brick, by any means in particular using a brush,
5 including a fine brush, a roller, a pad, a sprayer or an
aerosol, optionally after application to the substrate of
an adhesion primer.
It then forms, on this substrate, a film at ambient
10 temperature (<30°C), making it possible to confer on the
substrate the desired esthetic properties and to protect
the substrate, in particular against moisture.
A better understanding of the invention will be obtained
15 in the light of the following nonlimiting examples, the
aim of which is to illustrate the invention and not to
limit the scope thereof, defined by the appended claims.
EXAMPLES
20
Example 1: Preparation of polymer dispersions
A. General procedure
25 1) Starting materials
Use was made, for the preparation of the polymers
according to the invention, of the starting materials
shown in table 1 below.
30
WO 2014/207389 13 PCT/FR2014/051615
The Tg of the polymers was calculated as follows,
according to Fox's law:
5 1/Tg = xVTg1 + x2/Tg2+...xn/Tgn
where x represents the fraction by weight of the monomer
under consideration and Tg represents the glass
transition temperature of its homopolymer. In the tests
10 which follow, the values mentioned in table 2 below have
been retained:
WO 2014/207389 14 PCT/FR2014/051615
Table 2
2) Apparatus
5
The syntheses were carried out in a 3 1 (internal
capacity) glass reactor equipped with a jacket and
provided with efficient stirring (vortex), with a threeflow
reflux condenser and with control and regulation of
10 the material temperature. The reactor comprised the
number of inlets necessary for the separate introduction
of the different components and also an inlet dedicated
to rendering the assembly inert with nitrogen. The
leaktightness was confirmed before each synthesis. The
15 apparatus was equipped with a system which makes it
possible to adjust the flow rates for the introduction of
the components. The temperature of the material and also
the temperatures of the jacket were recorded and
adjusted. The synthesis was carried out semicontinuously.
20
3) Methods for characterizing the dispersions
a) Solids content (SC)
The solids content of the aqueous dispersions was
25 measured according to the ISO standard 3251.
b) pH
WO 2014/207389 15 PCT/FR2014/051615
The pH of the aqueous dispersions was measured
according to the ISO standard 976.
c) Viscosity
The viscosity of the aqueous dispersions was
5 measured according to the ISO standard 2555.
d) Size of the particles
The size of the particles was measured by Photon
Correlation Spectroscopy (PCS) using an N4+
device from Beckman Coulter. The sample was
10 diluted (3 to 5 drops of emulsion in 50 ml of
water) in a polystyrene vessel using deionized
water through a 0.22 pm cellulose acetate filter.
The size of the particles was measured at a
temperature of 25°C, under a measurement angle of
15 90° and at a wavelength of the laser of 633 nm.
e) Minimum film-format ion temperature (MFFT)
measured and expected as a function of the
structuring or nonstructuring of the particle
The MFFT of the aqueous dispersions was measured
20 according to the ISO standard 2115.
B. Syntheses carried out
A first polymer dispersion, hereinafter denoted
"Dispersion Dl", was prepared as follows.
25
15.25 g of a 40% solution of Emulsifier E30 were
dissolved in 1165.85 g of demineralized water as vessel
heel. The pH of the vessel heel was advantageously less
than 3. The temperature of the vessel heel was brought to
30 80°C.
WO 2014/207389 16 PCT/FR2014/051615
Separately, a preemulsion was prepared by dispersing
44.38 g of Emulsifier E30 (40%) and 83.33 g of Disponil
FES 77 (30%) in 865.04 g of demineralized water with good
stirring.
5 The following were added thereto in turn and with good
stirring:
- 1007.5 g of MMA
- 1462.5 g of 20ctA
10 The preemulsion thus formed was white and stable during
at least the time of the polymerization. It was kept
under gentle stirring.
Finally, different solutions of catalysts were prepared
15 as follows:
SI: 1.25 g of ammonium persulfate were dissolved in
11.25 g of water.
S2: 1.50 g of ammonium persulfate were dissolved in
148.50 g of water.
20 S3: 1.25 g of ammonium persulfate were dissolved in
123.75 g of water.
S4: 2 g of sodium metabisulf ite were dissolved in
198 g of water.
25 The polymerization was carried out in the following way.
i) Seeding
270.1 g of the preemulsion described above were
30 introduced, for the purpose of the seeding, into the
vessel heel including the initial charge stable at
80°C. Once the temperature had stabilized at 80°C,
100% of the solution SI, of 12.5 g, were added. The
WO 2014/207389 17 PCT/FR2014/051615
exothermicity maximum marked the end of this stage.
The particle size was approximately 60 nm and the
conversion was greater than 70%.
5 ii) Polymerization
The remainder of the preemulsion, and also 5 g of
AllylM and 25 g of AA, were introduced over 210
minutes at a polymerization temperature of 82°C.
10 The solution S2, i.e. 150 g, was run in in parallel
in 255 min.
iii) Stage of consumption of the residual monomers
15 The temperature was maintained at 82°C for 15
minutes. At the end of the thermal curing, the
following were run in separately and in parallel:
in 45 min, the solution S3, i.e. 125 g
in 75 min, the solution S4, i.e. 200 g,
20 still at 82°C. This redox treatment was followed by
curing at 82°C for 20 minutes before cooling to
ambient temperature.
iv) Final additions
25
The latex was neutralized at 30-35°C by addition of
sodium hydroxide solution up to pH 8-9 before adding
a biocide thereto. It was subsequently adjusted in
solids content and filtered through a 100 urn cloth.
30 The final solids content amounted to 47.6%.
WO 2014/207389 18 PCT/FR2014/051615
A dispersion Dl was obtained comprising a polymer based
on MMA/20ctA/AA/AllylM in the proportions by weight of
40.3/58.5/1/0.2, exhibiting a Fox Tg of 0°C.
5 The final particle size was approximately 130 nm, the
viscosity was less than 1000 mPa.s and the MFFT measured
was 5°C.
The list of the other aqueous dispersions prepared on the
10 basis of the same procedure is presented in table 3
below, with the compositions which vary from one test to
another being indicated.
T^hlA 3
15 In these three tests, 68.5 g of methacrylic acid were
added to the preemulsion and the AllylM was replaced with
a transfer agent, nDDM, in a proportion of 0.025 part.
20
C. Physicochemical characterization of the dispersions
The characteristics of the dispersions D2 to D4 obtained
are collated in table 4 below.
WO 2014/207389 19 PCT/FR2014/051615
Example 2: Physical properties
5 Each dispersion obtained in example 1 was applied, in the
film form, to a polypropylene plaque (800 urn wet) before
drying it at 23°C under 50% relative humidity for 7 days.
The following tests were then carried out:
10 Dynamic mechanical analysis (DMA) : Use was made of a
Mettler DMA8 61e device in shear mode, with scanning in
temperature from -50°C to 200°C, The temperature rise
gradient was 3°C/min and the frequency was 1 Hz.
15 Mechanical tests: Use was made of an MTS tensile testing
device regulated at a temperature of 23°C, a relative
humidity of 50% and a test rate of 500 mm/min, with a 50N
cell and a dumbbell-shaped test specimen.
20 The results obtained are collated in the following table
5.
'i
•i
WO 2014/207389 20 PCT/FR2014/051615
It emerges from this table that the differences between
5 the dispersions tested are extremely small, so that the
mechanical and viscoelastic properties of the films are
regarded as equivalent. The use of larger amounts of
20ctA does not modify them.
10 Example 3: Applicative evaluation
a. Formulation of the varnishes
Varnishes were formulated by using the starting materials
15 identified in table 6 below.
WO 2014/207389 21 PCT/FR2014/051615
The dispersions prepared in example 1 were formulated in
5 the form of varnishes (solids content by volume at 35%)
having the following compositions:
1
WO 2014/207389 22 PCT/FR2014/051615
5 b. Evaluation of the resistance to water
The above varnishes VI to V3 were applied to a glass
plate (200 urn wet) and dried at 23°C, 50% RH, for 7 days.
10 At the end of the 7 days, a drop of water was deposited
on the surface of the varnish film and left in contact
with the latter for 15 minutes, 30 minutes, 1 hour, 2
hours, 8 hours and then 24 hours. The bleaching of the
film on contact with water was then evaluated according
15 to the following scale of grading: 0 = no bleaching, 1 =
slight bleaching, 2 = moderate bleaching, 3 = intense
bleaching.
As is seen, the varnish V3 (formulated from the
dispersion D4 which contains the biobased monomer 20ctA)
exhibits a resistance to water equivalent to the varnish
5 VI, which is formulated with the dispersion D2 not
containing biobased monomer.
Example 4
10 Three other aqueous dispersions were prepared according
to the same procedure shown in example 1.
The compositions and characteristics are collated in
table 7 below:
15 Table 7
15
The mechanical tests as described in example 2 were
applied to these 3 dispersions, and also tensile tests at
5 mm/min carried out at -20°C.
5 The results are collated in table 8 below.
These tests shov/ that the dispersions D5 and D6 exhibit a
very low elongation at break at -20°C in comparison with
the dispersion D7, which has a Tg of -56°C.

CLAIMS
1. The use of a polymer resulting from the polymerization
of 2-octyl acrylate of renewable origin and optionally at
5 least one other monomer, as binding agent in or for the
manufacture of a coating composition, characterized in
that the polymer has a glass transition temperature (Tg),
calculated by Fox's law, of between -40°C and +40°C.
10 2. The use as claimed in claim 1, characterized in that
said other monomer is chosen from: vinylaromatic
monomers, such as styrene; ethylenically unsaturated
nitriles, such as acrylonitrile; esters of ethylenically
unsaturated mono- and dicarboxylic acids, such as 2-
15 ethylhexyl acrylate, n-butyl acrylate, methyl
methacrylate and itaconxc acid esters; esters of
monocarboxylic acid and vinyl or allyl alcohol, such as
vinyl acetate; ethylenically unsaturated mono- and
dicarboxylic and sulfonic acids, such as (meth)acrylic
20 acid, itaconic acid and styrenesulfonic acids; amides of
ethylenically unsaturated mono- and dicarboxylic acids,
such as acrylamide; N~vinyllactams, such as N-vinylpyrrolidone;
N-vinylamides; N,N-diallylamines; N,Ndiallyl-
N-alkylamines; allyl- or vinyl-substituted
25 nitrogenous heterocycles, such as N-vxnylimidazole and
vinyl- and allylpyridines; and their mixtures.
3. The use as claimed in claim 2, characterized in that
said other monomer is chosen from esters of ethylenically
30 unsaturated mono- and dicarboxylic acids, in particular
methyl methacrylate and n-butyl acrylate, vinylaromatic
monomers, more particularly styrene, and their mixtures.
WO 2014/207389 27 PCT/FR2014/051615
4. The use as claimed in any one of claims 1 to 3,
characterized in that the polymer has a glass transition
temperature (Tg), calculated by Fox's law, ranging from
-30°C to +30°C, more preferably of between -10°C and
5 +10°C, indeed even between -10°C and 0°C.
5. The use as claimed in any one of claims 1 to 4,
characterized in that the polymer is a copolymer
including from 30% to 75% by weight and more preferably
10 from 50% to 70% by weight of 2-octyl acrylate, with
respect to the total weight of the copolymer.
6. The use as claimed in any one of claims 1 to 5,
characterized in that the coating composition is a paint, •
15 mortar, coating, varnish or ink composition.
7. The use as claimed in any one of claims 1 to 6,
characterized in that the polymer represents, by dry
weight, from 5% to 50% by weight and preferably from 20%
20 to 40% by weight, with respect to the total weight of the
composition.