EP2707435A1

EP2707435A1 - Polymer-modified bituminous compositions

Info

Publication number: EP2707435A1
Application number: EP12719971.9A
Authority: EP
Inventors: Jörg ZIMMERMANN; Martin Hansson
Original assignee: Sika Technology AG
Current assignee: Sika Technology AG
Priority date: 2011-05-11
Filing date: 2012-05-09
Publication date: 2014-03-19
Also published as: WO2012152828A1

Abstract

The present invention relates to a bituminous composition, especially to a asphalt composition, comprising bitumen and a comb polymer KP. The invention further relates to the use of a comb polymer KP for decreasing the processing temperature of a bituminous composition, and for reducing the viscosity of bitumen in a bituminous composition and for improving the wettability of aggregates in a bituminous composition. The invention further relates to a process for producing a bituminous composition.

Description

Polymer modified bituminous compositions

Technical area

The invention relates to the field of polymer-modified bituminous compositions, in particular asphalt compositions. Of

Furthermore, the invention relates to the use of polymers in bitumen-containing compositions and to a process for the preparation of polymer-modified bituminous compositions.

State of the art

Asphalt refers to a mixture of bitumen and aggregates of natural or technical origin. Bitumen acts as a binder, which connects the aggregates to a mechanically stable and resilient body. Gravel, sand and / or aggregates are used in particular as aggregates. Asphalt is used especially in road construction or generally as a floor covering.

In the technical production of asphalt bitumen is liquefied, mixed with aggregates and compacted. For the liquefaction of the bitumen, various processes are known, which differ in particular with regard to the processing temperature. The best asphalt quality is generally achieved with so-called hot asphalt, which is usually processed at temperatures of 150-180 ^Q C. In such

Processing temperatures markedly decreases the viscosity of the bitumen, resulting in effective wetting and mixing with the aggregates

allows. On the other hand, the disadvantage of hot asphalt is, in particular, the relatively high energy requirement, which is due to the high processing temperatures. Various techniques are known today for reducing the processing temperatures of asphalt

Due to the addition of viscosity-reducing additives, foaming with water or the use of low-viscosity vegetable binders, the process temperature can be greatly reduced. Such produced asphalt is depending on

Processing temperature as warm asphalt (processing temperature

120 - 140 ^Q C), semi-warm asphalt (processing temperature <100 ^Q C) or cold asphalt (processing temperature "ambient temperature). US 2003/0231928 A1 (Schumann Sasol GmbH) describes in this context, for example, the use of FT paraffin (paraffin from a Fischer-Tropsch synthesis) as a viscosity-reducing agent in

Asphalt compositions.

Known techniques for reducing the processing temperature of

Asphalt compositions, however, generally have a number of disadvantages: for example, asphalts treated with wax or paraffin additives must be densified and discharged at sufficiently high temperatures to prevent premature crystallization of the additives. Foamed asphalts, which usually have a high water content of up to 30%, usually have a lower quality than hot asphalt.

There is therefore still a need for alternative ways to reduce the processing temperature of bitumen and

Asphalt compositions. Presentation of the invention

It is therefore an object of the present invention to improve the processability of bitumen-containing compositions and, in particular, to provide a more favorable preparation of qualitatively high-quality asphalt in terms of energy requirements. In addition, a corresponding bitumen-containing compositions and a process for their preparation to be provided. In particular, a flexible solution is to be found, which is also adaptable to different circumstances.

Surprisingly, it has been found that the object according to the invention is achieved by using the comb polymer KP defined in the claims in bitumen-containing compositions or a corresponding

bituminous composition comprising the comb polymer KP according to claim 1 can be solved.

Further aspects of the invention are the subject of further independent claims. Particularly preferred embodiments of the invention are the subject of the dependent claims.

As has been shown, the comb polymer KP can significantly reduce the viscosity of bitumen, in particular liquefied bitumen. This in turn allows a significant reduction of

Processing temperature of bituminous compositions, in particular of asphalt compositions. As a result, on the one hand, the processability of bituminous compositions can be greatly improved; on the other hand, the energy requirement in the case of processability of bituminous compositions can be reduced. In addition, the wettability of aggregates in bitumen-containing

Improve compositions, especially in asphalt compositions, by the use of the comb polymer KP. The comb polymers KP can also be produced in different chemical modifications and can thus be adapted to a wide variety of conditions.

The solution according to the invention therefore represents a new and advantageous alternative in comparison with the prior art.

Ways to carry out the invention

The term "bitumen" refers in the present context in particular high molecular weight, colloid-disperse mixtures of various organic substances which are obtained in the treatment of petroleum. For this purpose, suitable petroleum oils are, for example, high-sulfur, heavy Crude oils such as Arab Heavy, Kuwait, Iran Heavy, Urals, Kirkuk. In principle, however, the bitumen can also come from natural deposits, eg from sedimentary rocks such as copper shale and from natural asphalt.

A first aspect of the invention relates to a bituminous composition comprising bitumen and a comb polymer KP containing

a) a molar proportions of a partial structural unit S1 of the formula I)

b) b molar proportions of a partial structural unit S2 of the formula (II)

c) c molar proportions of a partial structural unit S3 of the formula (III) d) d molar proportions of a partial structural unit S4 of the formula (IV)

in which

M is independently H ⁺ , an alkali metal ion, alkaline earth metal ion, a divalent or trivalent metal ion, an ammonium ion or an organic ammonium group,

each R ^u independently of the others for hydrogen or a

Methyl group stands,

each R ^{v is} independently of the others hydrogen or COOM, m = 0, 1 or 2,

p = 0 or 1,

R ¹ and R ² independently of one another are a C ₁ - to C 20 -alkyl group, -cycloalkyl group, -alkylaryl group or - [AO] _n -R ⁴ ,

wherein A is C ₂ -C ₄ -alkylene, R ^{4 is} a C ₂ -C 20 -alkyl group, cyclohexyl group or -alkylaryl group, and n is 2-250, R ³ independently of one another are NH ₂ , -NR ⁵ R ⁶ , -OR ⁷ NR ⁸ R ⁹ , where R ⁵ and R ⁶ are each independently

a C to C ₂ o-alkyl group, cycloalkyl group

Alkylaryl group or aryl group,

or for a hydroxyalkyl group or for a

Acetoxyethyl- (CH ₃ -CO-O-CH ₂ -CH ₂ -) or a hydroxy isopropyl- (HO-CH (CH ₃ ) -CH ₂ -) or a

Acetoxyisopropyl group (CH ₃ -CO-O-CH (CH ₃ ) -CH ₂ -);

or R ⁵ and R ⁶ together form a ring, of which the

Nitrogen is a part of a morpholine or

Build up imidazoline ring;

R ^{7 is} a C ₂ -C ₄ -alkylene group,

R ⁸ and R ^{9 are} each independently a C 1 to C ₂₀ alkyl group, cycloalkyl group, alkylaryl group,

-Aryl group or a hydroxyalkyl group, and wherein a, b, c and d are the molar proportions of the respective

Represent partial structural units S1, S2, S3 and S4, with a / b / c / d / = (0.1-0.9) / (0.1-0.9) / (0-0.8) / (0.0-0.8),

in particular a / b / c / d = (0.3-0.9) / (0.1-0.7) / (0-0.6) / (0.0-0.4), more preferably a / b / c / d = (0.6-0.8) / ( 0.15 - 0.35) / (0.001 - 0.01) / 0, and the condition that a + b + c + d = 1.

The sequence of the partial structural units S1, S2, S3 and S4 can be alternating, block-like or random. In principle, it is also possible that, in addition to the partial structural units S1, S2, S3 and S4, further structural units are present.

The comb polymer KP preferably has a proportion of 0.005-10 wt.%, In particular 0.05-5 wt.%, Particularly preferably 0.1-3 wt.%, Based on the bitumen present in the bitumen-containing composition. In particular, a proportion of water in the composition based on the bitumen at most 15 wt .-%, in particular at most 10 wt .-%, particularly preferably at most 5 wt .-%, even more preferably at most 3 wt .-%.

A proportion of the bitumen in relation to all components of the bituminous components liquefiable at a temperature of at most 200 ^° C.

Composition is preferably at least 50% by weight,

in particular at least 75 wt .-%, particularly preferably at least 90 wt .-% is.

In other words, bitumen in the composition forms, in particular, the major proportion of the usual processing temperatures of

bituminous compositions, in particular at most 200 ^° C., in liquid form. As components which are not liquefiable at usual processing temperatures or are not in liquid form, for example, optional aggregates such as sand, gravel and / or aggregates are considered.

More preferably, all liquefiable at a temperature of at most 200 C ^Q components of the bituminous composition are substantially homogeneously mixed with the bitumen before, this in particular when the composition is in a flowable state is present and / or at a temperature of 90-200 C. ^Q

"Substantially homogeneously mixed" means, in particular, that the components liquefiable at a temperature of at most 200 ^° C. are not present as dispersion, emulsion and / or foam.

In particular, the bitumen-containing composition in a flowable state, in particular at a temperature of 90 - 200 ^Q C, a

Phase volume ratio of a liquid bitumen phase to any other and with the bitumen immiscible fluid phases> 0.8, preferably> 0.9, more preferably> 0.97, on.

However, it is in principle possible that the bitumen-containing composition in a flowable state contains, for example, small amounts of water. As has been shown, it is particularly advantageous if the comb polymer KP a glass transition temperature (T _g) of -20 - 150 ^Q C, in particular from 40 to 140 ^Q C, particularly preferably 80 - 130 ^Q C has. As a result, the

novel advantages in particular mass in appearance.

According to an advantageous embodiment, the comb polymer KP has one or more of the following features:

a) The radical R ^u is a methyl group, and / or

b) the radical R ^v is hydrogen, and / or

c) R ¹ is - [AO] _n -R ⁴ , where A is in particular C ₂ -alkylene, R is preferably a methyl group and with advantage n = 20-70, and / or

d) R ² is - [AO] _n -R ⁴ , where A is in particular a mixture of C ₂ - and C ₃ -alkylene, R _{4 is} advantageously a methyl group and

in particular n = 20-70. A weight-average molecular weight of the group - [AO] _n -R ⁴ is advantageously 1 Ό 00 - 3Ό00 g / mol. One

The molar ratio of the C ₂ -alkylene units to the C ₃ -alkylene units is in particular 25:75 to 75:25, in particular 40:60 to 60:40.

According to a further advantageous embodiment, the comb polymer KP is in particular free of aromatic compounds and / or aromatic structural units.

A weight-average molecular weight (M _w ) of the comb polymer KP is in particular 5Ό00 - 150Ό00 g / mol, in particular 1 0Ό00 - 100Ό00 g / mol.

The partial structural units S1, S2, S3, and S4 together preferably have a weight fraction of at least 50% by weight, in particular at least 90% by weight, very particularly preferably at least 95% by weight, on

Total weight of the comb polymer KP on. Also preferably, a total number of atoms present together in the partial structural units S1, S2, S3 and S4 is at least 50%, in particular at least 90%, very particularly preferably at least 95%, all in the comb polymer KP

present atoms. Furthermore, the bitumen-containing composition may optionally contain solid aggregates, the solid aggregates in particular containing sand, gravel and / or aggregates. In this case, the bitumen-containing

Composition in particular an asphalt composition.

In principle, however, in addition to or instead of the stated aggregates, other solids and / or fillers may also be present.

According to a particularly preferred embodiment, the

bitumen-containing compositions, in particular in a flowable state, the following composition: a proportion of bitumen of 2 - 20 wt .-%, a proportion of the comb polymer KP of 0.001 - 0.5 wt .-% and a content of aggregates of 80 - 98 wt. %, wherein in particular water has a content of at most 4 wt .-%. The percentages by weight are based on the total mass of the bitumen-containing composition.

Other aspects of the present invention relate to various

Uses of a comb polymer KP as defined above

Context with bitumen-containing compositions or

Asphalt compositions. As has been shown, the comb polymers KP are particularly suitable for the following uses or purposes:

Use of a comb polymer KP for reducing the viscosity of bitumen in a bitumen-containing composition, in particular in an asphalt composition.

Use of a comb polymer KP for improving the wettability of aggregates in a bitumen-containing composition, in particular in an asphalt composition.

Use of a comb polymer KP for reducing the

Processing temperature of a bitumen-containing composition, in particular an asphalt composition.

Use of a comb polymer KP for improving the

Mixability of bitumen with aggregates. The bitumen is in particular liquefied bitumen and / or the aggregates include or consist of sand, gravel and / or aggregates. Furthermore, the present invention relates to a process for the preparation of a bitumen-containing composition, in particular a

Asphalt composition, wherein in one process step a comb polymer KP, as defined above, is mixed into liquefied bitumen.

Optionally, aggregates, in particular sand, gravel and / or aggregates, can be mixed in addition to the comb polymer. In this case, in particular, an asphalt composition is produced.

According to an advantageous embodiment, at least a portion of the comb polymer KP is premixed with the aggregates prior to mixing into the liquefied bitumen, and the premix thus produced is admixed with the bitumen. In particular, all comb polymer KP before the

Mix in the liquefied bitumen premixed with the aggregates.

As it has been shown, through these measures, the effect of

Kammpolymer KP with respect to viscosity reduction and reduction of

Processing temperature of bituminous compositions can be further improved in some cases. In addition, the comb polymer KP can thereby be optimally distributed in the bitumen-containing composition, which leads in particular to more homogeneous compositions.

Further, it may be advantageous if at least a part of the aggregates after mixing the comb polymer KP in the liquefied bitumen

be mixed. In particular, all aggregates can be added only after the mixing of the comb polymer KP in the liquefied bitumen. As it has been shown, this may possibly facilitate the mixing of the aggregates with the bitumen, since the viscosity of the bitumen-containing composition is already reduced and, in general, the wettability of the aggregates is improved.

Likewise, the following method may be advantageous: In a first step, a first subset of the comb polymer KP is premixed with the aggregates before being mixed into the liquefied bitumen and a second subset

Subset of the comb polymer KP is mixed with the liquefied bitumen mixed. Subsequently, the aggregates are mixed with the blended first subset of comb polymer KP in the liquefied bitumen with the second subset of the blended comb polymer KP. One

Weight ratio of the first subset of comb polymer KP to the second subset of comb polymer KP may be e.g. 5:95 - 95: 5, especially 40:60 - 60:40. Such a method may be good in terms of

Effect of the comb polymer KP be advantageous at the same time good miscibility of the components of the bitumen-containing composition.

In principle, however, other types of mixing are possible.

Preferably, the comb polymer KP is dissolved in an aqueous solution and / or mixed as an aqueous suspension in the liquefied bitumen and / or mixed with the aggregates.

Advantageously, the liquefied bitumen during mixing of the

Kammpolymers KP a temperature of 90 - 160 ^Q C, in particular

100 - 130 ^Q C, up.

The aggregates point into the liquefied bitumen during mixing

advantageously a temperature of 90 - 160 ^Q C, in particular 90 - 130 ^Q C, on.

The preparation of the comb polymers KP is known in the art and can, for example, by free-radical polymerization of

corresponding monomers of the formula (I _m ), (II _m ), (III _m ) or (IV _m ), resulting in a comb polymer KP having the partial structural units S1, S2, S3 and S4. The radicals R ^u , R ^v , R ¹ , R ² , R ³ , M, m and p are defined as described above.

(Im) (Um) (U lm) (IV _m )

Likewise possible is the preparation of the comb polymers KP by polymer-analogous reaction of a polycarboxylic acid of the formula (V).

In the polymer-analogous reaction, the polycarboxylic acid of the formula (V) is esterified or amidated with the corresponding alcohols or amines (eg HO-R ¹ , H ₂ NR ² , H-R ³ ) and then at most neutralized or partially neutralized (depending on Type of the residue M, for example with metal hydroxides or ammonia). Details of the polymer-analogous reaction are disclosed, for example, in EP 1 138 697 B1 on page 7 line 20 to page 8 line 50, as well as in its examples or in EP 1 061 089 B1 on page 4, line 54 to page 5 line 38 and in its the examples. In a variant thereof, as described in EP 1 348 729 A1 on page 3 to page 5 and in its examples, the comb polymer KP can be produced in a solid state of aggregation. The Disclosure of these cited patents is hereby incorporated by reference in particular.

Corresponding comb polymers KP are also sold commercially by Sika Schweiz AG under the trade name series ViscoCrete®.

From the following exemplary embodiments and the totality of the claims, further advantageous embodiments and feature combinations of the invention result.

embodiments

1 . Used Kammpolvmere

For the subsequent experiments, a comb polymer KP1 was prepared in a manner known per se by polymer-analogous reaction of polymethacrylic acid with alcohols of the HO-R ^{1 type} and amines of the H ₂ NR ² type. The structure of the comb polymer KP1 thus produced corresponds to the above-described comb polymer KP, wherein:

R ^{u is} a methyl group;

- R ^{v is} hydrogen;

- m = 0 and p = 1;

R ¹ for a mixture of a methoxy-terminated polyethylene glycol having mass M _n = 1000 g / mol (PEG 1000-OCH ₃ ) and a methoxy-terminated polyethylene glycol having mass M _n = 3000 g / mol (PEG 3000)

OCH ₃ ). The molar ratio of PEG1000-OCH ₃ to PEG3000-OCH3 is 0.1 15: 0.138.

R ^{2 is} a methoxy-terminated ethylene oxide / propylene oxide copolymer with mass M _n = 2000 g / mol, the ethylene oxide and the por oxide units being present in a molar ratio of 50:50;

- a: b: c: d = 0.745: 0.253: 0.002: 0, and

- The molecular weight of the comb polymer (M _w ) about 60Ό00 g / mol

is. 2. Bitumen-containing compositions

A first bituminous composition B1 was prepared as follows: Conventional road construction bitumen of the grade 160/200 (for example available from Skanska Sverige AB) was liquefied by heating and subsequently admixed with 5% by weight of the comb polymer KP1. The comb polymer KP1 was present in the form of an aqueous solution (about 40% by weight of KP1 in water). After mixing the two components, the

Bituminous composition cooled to about 25 ^Q C.

For comparison purposes, a second bitumen-containing composition BV at about 25 ^Q C, consisting of pure street burnet of the variety

160/200, provided. Accordingly, the second bituminous contained

Composition BV no comb polymer KP1.

The hardness of the two bituminous compositions was determined by needle penetration procedures under identical conditions. The needle penetration was in each case carried out in accordance with the standard DIN EN 1426 at 25 ^° C. using a standard needle, a standard weight of 100 g and for a period of 5 seconds. Was determined thereby the

Penetration depth of the needle in 1/10-mm. Table 1 shows the results of the tests.

Table 1 :

From Table 1 it can be seen in particular that the addition of the

Comb polymer KP1 is able to significantly reduce the hardness of the bitumen. As has been shown, the sample B1 with comb polymer KP1 correspondingly has a lower softening point or a lower one

Condensing temperature on, as the sample BV without KP1. Accordingly, the use of comb polymers according to the invention makes it possible to reduce the processing temperature of bitumen. 3. asphalt compositions

Further, various asphalt compositions of the type ABT 1 1 160/220 (standard road asphalt, for example available from Skanska Sverige AB) were prepared as follows:

A first asphalt composition A1 was prepared by the asphaltene components (aggregates and bitumen of type 160/220) was heated to a temperature of 1 10 ^Q C in a first step. Subsequently, 5 wt .-% (based on the bitumen) were admixed comb polymer KP1 to the heated asphalt composition at a temperature of 1 10 ^Q C. A second asphalt composition A2 was prepared substantially like the first asphalt composition A1, the

Asphalt components in the first step, however, were heated up to 150 ^Q C. The admixture of the comb polymer KP1 is carried out in accordance with a temperature of 150 C ^Q.

For comparison, a third asphalt composition became A3

which was prepared substantially like the first asphalt composition A1. However, unlike the first asphalt composition A1, no comb polymer KP1 was added to the third asphalt composition A3.

Also for comparative purposes, a fourth asphalt composition A4 was prepared. This essentially corresponds to the second one

Asphalt composition A2, but the addition of a comb polymer KP1 was also omitted.

The four asphalt compositions A1 - A4 were compacted according to the standardized Marshall method. Using the thus prepared Marshall specimens, the air pore content of the specimens was subsequently determined in a manner known per se. Table 2 gives an overview of the test results. Table 2:

From the data presented in Table 2 it can be seen that the two asphalt compositions A1 and A2, which both contain the comb polymer KP1, have a significantly lower air pore content compared to the asphalt compositions A3 and A4 (without comb polymer KP1). Accordingly, the asphalt compositions A1 and A2 are also easier to compact compared with the other two asphalt compositions A3 and A4.

The air content of the asphalt composition A1 (containing KP1 and at a temperature of 1 10 ^Q C) corresponds approximately to the air content of the asphalt composition A4 (without KP1 and at a temperature of 150 ^Q C). It can be seen that the processing temperature of an asphalt composition due to the present invention comb polymers at constant

Significantly reduce air entrainment. This without the

Processability of the asphalt composition would be significantly impaired.

However, the embodiments described above are to be understood merely as illustrative examples, which may be modified as desired within the scope of the invention.

In particular, it is possible, for example, to use other inventive comb polymers KP instead of the comb polymer KP1. It is the same possible to provide other types of bitumen or other types of asphalt compositions.

Claims

claims

1 . Bitumen-containing composition, in particular a

An asphalt composition comprising bitumen and a comb poly KP containing

a) a molar proportions of a partial structural unit S1 of the formula (I)

b) b molar proportions of a partial structural unit S2 of the formula (II)

c) c molar proportions of a partial structural unit S3 of the formula

d) d molar parts of a partial structural unit S4 of the formula (IV)

in which

each R ^u independently of the others for hydrogen or a

Methyl group stands,

each R ^{v is} independently of the others hydrogen or COOM, m = 0, 1 or 2,

p = 0 or 1,

A = C ₂ - to C -alkylene, R ^{4 is} H, a C ₁ - to C ₂₀ -alkyl group, -cyclohexyl group or -alkylaryl group, and n = 2-250,

R ³ independently of one another are NH ₂ , -NR ⁵ R ⁶ , -OR ⁷ NR ⁸ R ⁹ ,

wherein R ⁵ and R ^{6 are} independently for

a C 1 to C ₂₀ alkyl group, cycloalkyl group

Alkylaryl or aryl group, or for a hydroxyalkyl group or for an acetoxyethyl (CH ₃ -CO-O-CH ₂ -CH ₂ -) or a hydroxyisopropyl- (HO-CH (CH ₃ ) -CH ₂ - ) or one Acetoxyisopropyl group (CH ₃ -CO-O-CH (CH ₃ ) -CH ₂ -);

or R ⁵ and R ⁶ together form a ring, of which the

Nitrogen is a part of a morpholine or

Build up imidazoline ring;

R ^{7 is} a C ₂ -C ₄ -alkylene group,

R ⁸ and R ⁹ each independently of one another represent a C 1 to C ₂₀ alkyl group, cycloalkyl group, alkylaryl group,

-Aryl group or a hydroxyalkyl group, and wherein a, b, c and d are molar proportions of the respective partial structural units

S1, S2, S3 and S4, with

a / b / c / d / = (0.1-0.9) / (0.1-0.9) / (0-0.8) / (0.0-0.8),

in particular a / b / c / d = (0.3-0.9) / (0.1-0.7) / (0-0.6) / (0.0-0.4) and the proviso that a + b + c + d = 1.

2. Bituminous composition according to one of the preceding

Claims, characterized in that the comb polymer KP based on the bitumen has a content of 0.005 to 10 wt .-%, in particular 0.05 to 5 wt .-%, particularly preferably 0.1 to 3 wt .-%.

3. Bituminous composition according to one of the preceding

Claims, characterized in that a proportion of water in the composition based on the bitumen at most 1 5 wt .-%, in particular at most 10 wt .-%, particularly preferably at most 5 wt .-%, is.

4. Bituminous composition according to one of the preceding

Claims, characterized in that a proportion of the bitumen based on all at a temperature of at most 200 ^Q C liquefiable components of the bitumen-containing composition is at least 50 wt .-%, in particular at least 75 wt .-%, particularly preferably at least 90 wt .-% ,

5. Bituminous composition according to one of the preceding claims, characterized in that the comb polymer KP has a glass transition temperature (T _g ) of -20-150 ^Q C, in particular 40

- 140 ^Q C, more preferably 80 - 130 ^Q C, has.

6. Bituminous composition according to one of the preceding

Claims, characterized in that in the comb polymer KP the radical R ^{u is} a methyl group, the radical R ^{v is} hydrogen, m = 0, p = 1 and R ^{1 is} - [AO] _n -R ⁴ where n = 20 - 70 stands.

7. Bituminous composition according to one of the preceding

Claims, characterized in that solid aggregates are contained, wherein the solid aggregates include in particular sand, gravel and / or aggregates.

8. Bituminous composition according to claim 7, characterized

characterized in that a proportion of bitumen 2 - 20 wt .-%, a proportion of the comb polymer KP 0.001 - 0.5 wt .-% and a proportion of aggregates 80 -

98 wt .-%, wherein in particular water has a content of at most 4 wt .-%.

9. Use of a comb polymer, which is defined as the comb polymer KP in any one of claims 1-8, for reducing the viscosity of bitumen in a bitumen-containing composition, in particular in an asphalt composition.

Use of a comb polymer, which is defined as the comb polymer KP in one of claims 1-8, for improving the

Wettability of aggregates in a bitumen-containing

Composition, in particular in an asphalt composition.

1 1. Use of a comb polymer, which is defined as the comb polymer KP in one of claims 1-8, for reducing the

12. A process for the preparation of a bitumen-containing composition, in particular a bitumen-containing composition according to any one of claims 1-8, characterized in that in one

Process step a comb polymer KP, which, like the comb polymer KP according to one of claims 1-8 is defined, is mixed in liquefied bitumen.

A method according to claim 12, characterized in that in addition to the comb polymer KP aggregates, in particular sand, gravel and / or aggregates are admixed.

A method according to claim 13, characterized in that the comb polymer KP before mixing into the liquefied bitumen at least partially or completely premixed with the aggregates and the premix thus prepared is added to the bitumen. Method according to one of claims 12-14, characterized in that the liquefied bitumen during mixing of the comb polymer KP has a temperature of 90 - 160 ^Q C, in particular 100 - 130 ^Q C, having.