FR2493329A1 - BITUMINOUS COMPOSITION - Google Patents

Abstract

Bituminous compositions having good energy-absorption properties contain bitumen, cured extract, a finely divided, crosslinked non-thermoplastic rubber and a filler, the amount by weight of the finely divided, crosslinked, non-thermoplastic rubber being greater than or equal to the amount by weight of the filler, and the bitumen being a rubber-containing bitumen in which the rubber is a non-thermoplastic copolymer of at least two mono- alpha -olefins and a cyclic olefin containing an endocyclic bridge and at least two olefinic double bonds. The compositions can be shaped to give boards or sheet-like materials using rubber mixing units and are suitable as safety coverings, for example for children's playgrounds.

Description

 The present invention relates to a composition which contains bitumen and rubber having energy absorbing properties and suitable for use, for example, as a safety surface on children's playgrounds.

 Various compositions containing bitumen and rubber and possessing greater or lesser properties of energy absorption are already known. In particular, compositions have been proposed which contain bitumen, thermoplastic rubber and non-thermoplastic rubber. For example, GB Patent Specification 2,036,760A discloses a bituminous composition having energy absorbing properties and comprising bitumen, hardened extract, thermoplastic rubber, finely divided particles of non-rubber, thermoplastic and a filler, a composition in which the amount of non-thermoplastic rubber is equal to or greater than the amount of filler, by weight.

 Although a thermoplastic rubber is an indispensable component of the bituminous compositions prepared according to the aforementioned GB patent application, the Applicant has found, surprisingly, that bituminous compositions having similar properties can be prepared by using a rubberized bitumen with a non-thermoplastic rubber. to replace bitumen and thermoplastic rubber. The use of a rubberized bitumen also makes it possible to reduce the mixing and / or premixing necessary during the production of the energy absorption compositions, which can thus be obtained under more economical conditions.

 According to the present invention, a bituminous composition having energy absorbing properties comprises bitumen, a cured extract, finely divided particles of a non-thermoplastic crosslinked rubber and a filler, the proportion of finely divided particles of non-thermoplastic rubber. crosslinked, by weight, being equal to or greater than the proportion by weight of the filler, the composition in which the bitumen is a rubber bitumen, the rubber for the rubberized bitumen is a non-thermoplastic copolymer of at least two monoalpha-olefins and a cyclic olefin having endocyclic bridging and at least two olefinic double bonds.

The energy absorbing compositions according to the invention advantageously contain the following weight proportions of the stipulated ingredients.
Rubber bitumen: 100 parts
Hardened extract: 4-40 parts
Rubber particles
non-thermoplastic
crosslinked: 50-175 parts
Charge: 50-175 parts
The compositions may also contain a long chain hydrocarbyl amine (e.g. octadecylamine) in a weight ratio of 0.05 to 5 parts and preferably 0.1 to 0.5 parts (based on the weight of the rubber bitumen). ) to facilitate the kneading and grinding of the composition.

 The above-mentioned proportion of crosslinked non-thermoplastic rubber is the amount of finely divided particulate rubber excluding the non-thermoplastic rubber present in the rubberized bitumen.

 Rubberized bitumens in which the rubber is a non-thermoplastic copolymer of at least two mono-alpha olefins and an acyclic olefin having an endocyclic bridging and at least two double bonds are already known. The olefins may be ethylene and propylene while the cyclic olefin may be dicyclopentadiene or ethylidene norbornene, which rubbers are commonly referred to as EPDM rubbers.

 To ensure homogeneity between the rubber and the bitumen, the copolymer can be incorporated in the bitumen by a technique of insufflation of the copolymer with an aromatic fluxing oil at a temperature of 150 to 3000C in the presence of a gas containing elemental oxygen. The mixture to be insufflated may comprise all or part of the bitumen. If the mixture to be insufflated does not contain bitumen or only a part of it, then the unfuffed product is mixed as necessary with non-furred bitumen. Suitable rubber bitumens can be prepared by the methods described in GB 1 304 238, 1325847, 1327535 and 1385706.

 GB Patent 1,304,238 describes a process for the preparation of a bituminous composition that can serve as a surface material for a roof, in which a gas containing elemental oxygen at a temperature of 150 to 3000 ° C is insoluble in a mixture of 23 to 88 0% (relative to the total weight of the mixture) of a bituminous substance, 2 to 25% (relative to the total weight of the mixture) of a copolymer of at least two mono-alpha olefins and a cyclic olefin having an endocyclic bridging and at least two olefinic double bonds, 10 to 75% (based on the total weight of the mixture) of a fluxing oil to elongate the copolymer, 0 to 4 parts of sulfur relative to 100 parts by weight; copolymer weight and 0 to 3% (based on the total mixture) of a polyolefin.

 GB 1 325 847 relates to a method for producing a bituminous composition, comprising mixing a bituminous substance, a copolymer of one or more mono-alpha olefins and a cyclic olefin containing an endocyclic bridging and at least two double bonds olefinic bonds, an aromatic fluxing oil and optionally sulfur, and then blowing into this mixture at a temperature of 150 to 2600C a gas containing elemental oxygen to form a concentrate and finally dissolve this concentrate in non-bitumen. breathed.

 GB 1 327 535 discloses a method for producing a bituminous composition, wherein a gas containing elemental oxygen in a mixture of 10 to 85% (based on total weight) is blown at a temperature of 180 to 2600C. of the mixture) of a bituminous substance, 5 to 25% (based on the total weight of the mixture) of an ethylene / propylene / cyclic olefin copolymer having an endocyclic bridging and at least two olefinic doubleglomerates, and 10 to 85% (by relative to the total weight of the mixture) of a fluxing oil to elongate the copolymer, the elastomer being in the form of a latex when added to the bitumen.

 Finally, GB 1 385 066 discloses a process for producing a bituminous composition, according to which an oxygen-containing gas is blown at a temperature of 150 to 2600C to form a concentrate in a mixture of an aromatic oil method of fluxing, an elastomeric copolymer of one or more alpha-olefins and an unsaturated hydrocarbon having more than one olefinic double bond and an endocyclic bridging comprising one or more methylene groups and optionally up to 10 parts by weight of sulfur per 100 parts of elastomeric copolymer, and then the concentrate is dissolved in the non-blown bitumen.

The preferred methods of producing a rubberized bitumen for use in the compositions according to the invention are those which have been described in US Pat.
GB 1,304,239 and 1,325,847.
Suitable rubber bitumens include those sold under the trademark "Olexobit" by Deutsche
BP AG.

 The finely divided particles of non-thermoplastic crosslinked rubber may be, for example, less than 0.83 mm in size. The rubber may be a vulcanized rubber, for example a synthetic rubber such as SBR or polybutadiene, or a natural rubber. This rubber may be extended or diluted with an oil and / or contain one or more fillers and may be a by-product material in the manufacture of various rubber articles, for example crumbs of tire, which are the waste obtained during the standardization or the rectification of the treads of tires.

 The finely divided particles of a crosslinked non-thermoplastic rubber are not believed to mix with the rubberized bitumen but remain as separate particles which impart rigidity to the composition.

 Any normal charges may be used for the bituminous compositions. The fillers may be fibrous, but it is preferred that they be pulverulent. Suitable fillers include the following products: limestone powder, silica, alumina, Portland cement, barite, pulverized fuel ash, talc and asbestos fibers. The presence of a small amount of talc is advantageous during the kneading and the load may comprise from 1 to 20 parts, relative to the total weight of the mixture, of talc that is added to the kneading operation.

 The cured extract can be prepared by blowing into a petroleum extract a gas containing oxygen, preferably air, at a temperature of 250 to 3500C in the absence or in the presence of a catalyst, for example a Friede Kraft metal halide, such as ferric chloride. Extracts of petroleum are obtained by extraction with a solvent of fractions of petroleum distillate, boiling in the range of lubricating oils, that is to say between 350 and 6000C and containing a preponderant proportion of aromatic hydrocarbons .

 It is believed that the blowing of the extract causes the condensation of the aromatic components to thereby obtain a cured product containing a high proportion of asphaltenes, cyclic products and insoluble products and a relatively low proportion of saturated products.

The cured extract can have a penetration of 0.1 to 6 at a temperature of 250C, determined by the ASTM test
D5 / 73 and a softening point (ball and ring) of 60 to 1700C.

 The weight ratio of the non-thermoplastic rubber particles to the filler is advantageously between 1: 1 and 3: 1. The hardness of the compositions can be adjusted by the proportions of the cured extract and the filler, the hardness being advantageously from 30 to 60 on the IRHD scale. At lower hardness values, the compositions tend to be soft and tacky whereas at higher hardness values the compositions tend to become too rigid and exhibit only reduced energy absorption properties.

 The rebound resilience of the compositions according to the invention does not exceed 20 Ojj! at 250C, when measured by falling two weights or using a pendulum (eg the Lüpke pendulum method). This figure should be compared to that of more than 30% which characterizes most rubbers and indicates that the compositions have a high capacity for absorption of impact energy.

 Another interesting feature of the compositions according to the invention is the ease with which they are deformed under load and resume fairly quickly their initial dimensions. The usual recoveries of the measurement of an impact deformation may be to twist 80% or more after twenty-four hours.

 Permanent compression is the reverse of recovery and represents the residual deformation of a specimen when it has been subjected to compression under defined conditions. Normally the permanent compressions for the compositions according to the invention are less than 20% when measured 24 hours after a compression of 25 to 230C during 22 hours.

 The compositions according to the invention can be prepared by mixing the ingredients together in a high intensity mixer, for example a Banbury mixer, for a period of from 2 to 60 minutes. The components can be loaded into the Banbury mixer at room temperature and this temperature can rise to about 1600C under the effect of frictional forces. The material from the Banbury mixer can then be shaped by conventional sheet molding or forming techniques. For example, sheets can be prepared with the compositions by grinding and calendering or by extrusion in a roller die.

 The compositions according to the invention may contain a number of additives to facilitate the treatment of the material or to improve the properties thereof. For example, the presence of a long chain hydrocarbylamine, as previously mentioned, prevents the material from sticking to the rolls during calendering and, if the material is to be molded, the presence of a small proportion, for example 0.1 at 2% by weight relative to the weight of the rubberized bitumen, a fatty acid amide, such as an oleamide or stearamide, facilitates demolding of the shaped article. A paraffinic oil such as "Enerpar 23" sold by BP Oil or an aromatic oil such as "Enerflex 72", also sold by BP Oil, may be added at a rate of up to 5% by weight as adjuvant of The presence of the oil makes it possible to reduce the time required for the treatment of the compositions in the mixer. An anti-ozone agent such as "Santoflex IP" sold by Monsanto can be incorporated in an amount of from 0 to 1% by weight to improve the resistance of the materials to ozone cracking during exposure to conditions. adverse atmospheres.

 Sheets or tiles can be formed with compositions according to the invention to prepare safety surfaces, for example on children's playgrounds, more particularly in the vicinity of swings, slides and other apparatus where the children may fall. These compositions can also be used for bumpers that absorb energy and are installed on motor vehicles or to make ship fenders or barriers on highways.

Normally the material can be molded into sheets having dimensions of 500 x 500 x 16 mm to form a safety pavement. These paving slabs can be attached to an underlying surface, for example asphalt or concrete using an adhesive. A suitable adhesive may contain the following ingredients, by weight
Bitumen: 91 to 95 parts
Rubber particles
thermoplastic: 5 to 9 parts, preferably
7 to 8 parts
1,1,1-trichloroethane: 55 to 100 parts
Normally a suitable adhesive can be prepared by mixing 57.5% by weight of a penetration bitumen 100,
4.7 gb by weight of a thermoplastic rubber "Solprene"
411P sold by Phillips Petroleum, ("Solprene" is
a registered trademark), and 37.8% by weight of 1,1,1-trichloroethane.

 The following Examples, in which all proportions are by weight, unless otherwise stated, serve to illustrate the invention without in any way limiting its scope. Crumbs or tire scraps are used in all examples as finely divided particles of a crosslinked non-thermoplastic rubber.

EXAMPLE 1
The following materials are fed into the mixing chamber of a Banbury mixer with a capacity of 1 liter:
616 g of "Olexobit 50", a rubber bitumen sold by
Deutsche BP AG,
205 g of a hardened extract (140 C softening point),
684 g of "Snowcal" 6ML, limestone load sold by
Cement Marketing Company Limited. ("Snowcal" is
a registered trademark)
900 g of tire crumbs of a dimension of
0.38 mm
4.8 g of octadecylamine.

 The charge is mixed at 20 rpm for 35 minutes and a temperature of about 20 ° C. is reached. The material is discharged from the mixer and milled for 5 minutes on a two roll mill (30.5 cm wide) to produce a sheet suitable for molding.

 Product samples were molded at 1600C for 5 minutes under a load of 20 tonnes in a 20.3 x 20.3 cm press. The molded samples are used for measurement tests of the physical properties of the material, the results of which are shown in Table 1. For comparison purposes, the physical properties of a composition prepared according to GB 2 are also shown in the table. 036 760A and two other commercial products. Comparative Material 1 is a material which comprises granulated rubber bonded with an elastomeric polyurethane resin. Comparative Matter 2 is a similar material that can be laid in the wet state.

 Dumbbell shaped specimens are prepared from a sheet having a thickness of 3 mm and used to determine the mechanical strength and elongation in accordance with BS 903 Pt. A2 1971 type 1. of 50 cm / min at 230 ° C. and the results which appear in Table I show that the material according to the invention is more resistant and capable of a much greater elongation than the material according to the patent GB 2,036,760 A or Comparative Matter. 2. Comparative Matter 1 is not subject to this test.

 The Lugke pendulum method is used to measure resilience. We use a pendulum weighing 250 g and suspended at a height of 2 meters at an angle of 180 from the vertical. The height of the first rebound, expressed as a percentage of the height of the initial fall, is a measure of the resilience of the material.

The rebound resilience of the specimens is measured at temperatures of -120C, 230C and 600C.

 The results obtained with the material according to the invention are very similar, at all temperatures, to those of the material prepared according to patent GB 2 036 760A, but are much lower than those obtained with tire crumbs agglomerated with using a binder (comparative material 1). This indicates that the energy absorption properties according to the invention are at least as good as those of the material according to GB 2,036,760A and are better than those of Comparative Material 1.

 The "tetrapod" go test is a simulated wear test that more closely matches the actual wear than, for example, an abrasion test: a molded sheet of material 30 cm wide, 3 mm thick is fitted Thickness and a known weight in a cylindrical drum having a diameter of 22 cm The edges are rubbed together and held in place by means of an adhesive tape A tetrahedral shaped device called "tetrapod" weighing 507 g is installed inside the cylinder and the ends are sealed with a polythene sheet 5 mm thick and a metal support plate.This device includes four equidistant arms (spacing 12.5 cm) and each 15 mm moving spindles.The cylindrical drum is rotated with rollers for 500,000 revolutions at 38 rpm, the specimen is then removed from the drum, wear is examined, and weight is weighed. calculate the loss of mass or volume during the test.

 A hexagonal pattern is molded on one side of the test pieces for this test. After the 500,000 revolutions, the pattern is still visible on the specimen made of material according to the invention while on the specimen according to GB 2 036 760A there is no evidence of the original pattern and the wear is also stronger. With respect to a sample of the bonded tire crumb material, ie Comparative Material 1, wear is severe and large areas of rubber have been torn from the specimen by the moving tips.

Thus a large volume of rubber crumbs was torn off the surface. Comparative Matter 2 also undergoes severe wear.

 The peak deceleration force refers to the maximum deceleration force experienced by a 4.1 kg mass when dropped onto a molded sample having at least 15 cm x 15 cm and 16 mm thickness.

The response is measured using a decelerometer; the load is amplified and transmitted to a transient recorder.

The peak deceleration force is measured from the graph that appears on the graph paper.

 The mass used is a spherical segment having a radius of 50 mm and forming part of a sphere having 65 mm radius.

 The material according to the invention behaves as well as all the other materials tested (see Table I page 15).

EXAMPLE 2
In a Banbury mixer, 63 kg of "Olexobit 50" which is a rubberized bitumen, 21 kg of hardened extract (softening point 1400 ° C), 70 kg of "Snowcal 7ML" which is a calcareous load, 92 kg of tire crumbs with a particle size of 0.38 mm, 0.612 kg of octadecylamine and 1.225 kg of oleamide. The compound compound reaches a temperature of 1530C as a result of the frictional heating during mixing. The product is discharged on a 2 meter wide two roll mill and milled to form a sheet about 9 mm thick. The material of the mill is removed when this material is at a temperature of 1100C.

 1900 g samples of this product are milled on a 2-roll cold laboratory mill for 5 minutes to form tiles measuring 30.5 x 30.5 x 1.6 cm. The IRHD hardness is measured on two samples over a range of temperatures. The results are reproducible and are shown in Table II (see Table II page 16).

EXAMPLE 3
The following ingredients are mixed in a Banbury mixer for 18 minutes and reached a peak temperature of 1800 ° C.: 51 g of "Olexobit 50" (rubberized bitumen), 170 g of hardened extract (softening point 1400 ° C.), 578 g. of "Snov-cal 7ML" (calcareous load), 747 g of tire crumbs with a particle size of 0.38 mm and 4 g of octadecylamine.

The material is molded and specimens are obtained to measure the following physical properties:
hardness IRHD: 48 (at 230C)
Resilience to rebound: 15%
Permanent compression: 17 5o '
(measured 24 hours later
25% compression
for 22 hours at
230C)
EXAMPLE 4
Two compositions are prepared by mixing in a Banbury mixer the following materials to a peak temperature of 1450C.

relative to the total weight of
mixed
Material Composition 1 Composition 2 "Olexobit 50" (rubber bitumen) 25.6 34.1 "Snowcal 7ML" (calcareous load) 28.5 28.5
Tire crumbs (0.38 mm) 37.4 37.4
Hardened extract (140 C softening point) 8.5
100.0 100.0
Both compositions also contain 1% octadecylamine and 2% oleamide (based on the weight of "Olexobit 50").

 The tile compositions were molded 305 x 305 x 16 mm and had a contoured (or patterned) upper surface and a plain bottom surface. The materials are molded either (a) with silicone release paper, or (b) with aluminum foil between the plates.

The wet wipe strengths of the tile surface of each composition are measured using a portable slip resistance of the composition.
Road Research Laboratory. The results are shown in Table III (see Table III, page 16).

 Compositions 1 and 2 in sheets measuring 80 × 80 × 16 mm were also molded and cooled to -50 ° C. in a thermostatically controlled water and glycol bath. Samples of both materials survive after a 5-joule impact test and a 1800 deflection around a 3-cm diameter mandrel. These results indicate that the incorporation of a hardened extract in no way detracts from the energy absorption or flexibility of the materials at low temperatures.

EXAMPLE 5
16 tiles measuring 300 x 300 x 16 mm were prepared with the composition described in Example 1. These tiles were bonded to an asphalt surface using four bitumen-based adhesives which were prepared as follows.

 Adhesive 1 - 1850 g of a penetration bitumen 200 are heated to a temperature of 1000 ° C. in an oven and then transferred to a flask with a capacity of 5 liters equipped with a stirrer and a condenser of reflux.

1214 g of 1,1,1-trichloroethane are added and stirred to form a solution at 700 ° C. 150 g of "Solprene" 411 P, which is a Phillips Petroleum thermoplastic rubber, are added to the solution and refluxed at 8 ° C. for one hour to dissolve the rubber. The contents of the flask are cooled to 50 C.

 Adhesive 2-Same technique as for the adhesive 1 except that a penetrating bitumen 100 is used.

 Adhesive 3 - Same technique as for the adhesive 1 except that a penetrating bitumen 100 is used and the proportion of "So1prene" 411P is increased to 200 g.

 Adhesive 4 - 692 g of penetrating "Olexobit" bitumen 100 were dissolved in 1237 g of 1,1,1-trichloroethane by stirring under reflux in a 5-liter flanged and round-bottomed flask with a condenser. reflux.

 The surface of the asphalt is pre-treated with a primer prior to bonding the tiles to the surface. The primer for adhesives 1 to 3 comprises a mixture of 92 parts of bitumen, 7.5 parts of Solprene 411P and 245 parts of 1,1,1-trichloroethane. The primer for adhesive comprises 87 parts of "@lexobit" 100 dissolved in 311 g of 1,1,1-trichloroethane.

 Four tiles are glued to the surface with each adhesive. After 6 months, the force required to pull the tiles is measured with a spring balance equipped with a 1.5 x 2.5 cm edge plate that is inserted under the edge of the tiles. The average force in kg required to tear the tiles bound by each of the 4 adhesives is shown in Table IV (See Table IV page 17).

TABLE I
Physical Properties of a Molded Safety Surface Prepared According to Example 1 and Other Commercial Products

Property <SEP> Units <SEP> Tile <SEP> Tile <SEP> Material <SEP> Material
<tb> molded <SEP> pre- <SEP> molded <SEP> compared- <SEP> compared <SEP> according to <SEP> according to <SEP> tive <SEP> 1 <SEP> tive <SEP> 2
<tb> GB <SEP> 2036760A <SEP> Example <SEP> 1
<tb> Thickness <SEP> mm <SEP> 16 <SEP> 16 <SEP> 16 <SEP> 15
<tb> Density <SEP> 1.2 <SEP> 1.28 <SEP> 0.65
<tb> Resiliency <SEP> at <SEP> rebound <SEP>%
<tb> (-12 C) <SEP> 9 <SEP> 8 <SEP> 31
<tb> (23 C) <SEP> 14 <SEP> 15 <SEP> 51 <SEP> 25-30
<tb> (60 C) <SEP> 21 <SEP> 22 <SEP> 55
<tb> Hardness <SEP>(<SEP> IRHD Scale)
<tb> to <SEP> 23 C <SEP> degree <SEP> 40-45 <SEP> 30 <SEP> 35-40 <SEP> 35
<tb> Resistance <SEP> to <SEP><SEP> tensile <SEP> MPa <SEP> 0.4 <SEP> 1.3 <SEP> 0.8
<tb> Lengthening <SEP> to <SEP><SEP> Breaking <SEP>% <SEP> 50 <SEP> 330 <SEP> 100
<tb><SEP> Wear Test <SEP> at <SEP> tetrapod <SEP> mg / m2 <SEP> 30-40 <SEP> 0 <SEP> 1400 <SEP> 800
<tb> of <SEP> Walker <SEP> port <SEP> by
<tb> 500,000
<tb> revs
<tb> Strength <SEP> of <SEP> Deceleration <SEP> of <SEP> g <SEP> 300 <SEP> 313 <SEP> 310 <SEP> 280
<tb> tip <SEP> (hemisphere <SEP> of <SEP> 4 <SEP> kg
<tb> falling <SEP> of a <SEP> height <SEP> of
<tb> 1 <SEP> meter)
<tb> TABLE II
Hardness (IRHD Scale) of the molded material

Temperature <SEP> (C) <SEP> -10 <SEP> 0 <SEP> 10 <SEP> 23 <SEP> 40 <SEP> 50
<tb> IRHD <SEP> Sample <SEP> 1 <SEP> 80 <SEP> 73 <SEP> 67 <SEP> 50.5 <SEP> 42 <SEP> 33
<tb> (degrees) <SEP> Sample <SEP> 2 <SEP> 82 <SEP> 75 <SEP> 69.5 <SEP> 50 <SEP> 38 <SEP> 31
<tb> TABLE III
Resistance to wet skidding

Material <SEP> Hardness <SEP> IRHD <SEP> to <SEP> 23 C <SEP> Type <SEP> of <SEP> Material <SEP> of <SEP> Strength <SEP> at
<tb> (degree) <SEP> surface <SEP> demoulding <SEP> skid <SEP> at
<tb> wet
<tb> Composition <SEP> 1 <SEP> 50 <SEP> profiled <SEP> silicone <SEP> 41
<tb> profiled <SEP> foil <SEP> 42
<tb> aluminum
<tb> united <SEP> silicone <SEP> 41
<tb> Composition <SEP> 2 <SEP> 50 <SEP> profiled <SEP> silicone <SEP> 28
<tb> profiled <SEP> foil
<tb> aluminum <SEP> 16
<tb> united <SEP> silicone <SEP> 18
<tb> united <SEP> tinsel
<tb> aluminum <SEP> 12
<tb> These results show that Composition 1 has a much higher skid resistance than Composition 2 regardless of the material used for demolding. Composition 2 differs from Composition 1 in that all of the cured extract has been replaced by "Olexobit 50", but the materials have similar hardnesses. As a result, the presence of a cured extract seems beneficial to obtain a material having better skid resistance.

TABLE IV
Force required to tear asphalt-related tiles

Type <SEP> Adhesive <SEP> Strength <SEP> Medium <SEP> (kg) <SEP> Required <SEP> for
<tb> raise <SEP> a <SEP> tile <SEP> of <SEP> the <SEP> surface
<tb> of <SEP> the asphalt
<tb> 1 <SEP> - <SEP> Contains <SEP> 7.5 <SEP>% <SEP> of <SEP>"Solprene"
<tb> in <SEP> a <SEP> bitumen <SEP> of <SEP> penetration <SEP> 200 <SEP> 5
<tb> 2 <SEP> - <SEP> Contains <SEP> 7.5 <SEP>% <SEP> of <SEP>"Solprene"
<tb> in <SEP> a <SEP> bitumen <SEP> of <SEP> penetration <SEP> 100 <SEP> 19
<tb> 3 <SEP> - <SEP> Contains <SEP> 10.5 <SEP>% <SEP> of <SEP>"Solprene"
<tb> in <SEP> a <SEP> bitumen <SEP> of <SEP> penetration <SEP> 100 <SEP> 2.7
<tb> 4 <SEP> - <SEP>"Olexobit",<SEP> asphalt <SEP> to
<tb> penetration <SEP> 100 <SEP> 4,5
<tb> These results show that the adhesive 2 has a remarkable ability to bind tiles to asphalt.

Claims (11)

 A bituminous composition having energy absorbing properties, comprising bitumen, hardened extract, finely divided particles of a non-thermoplastic crosslinked rubber and a filler, the weight proportion of the finely divided particles of crosslinked non-thermoplastic rubber being equal to or greater than the weight amount of filler, characterized in that the bitumen is a rubber bitumen, and in that the rubber in the rubberized bitumen is a non-thermoplastic copolymer of at least two mono-alpha olefins and an olefin cyclic compound comprising endocyclic bridging and at least two olefinic double bonds.  2 - Composition according to claim 1, characterized in that the technique of preparation of the rubberized bitumen comprises the operation of insufflation in the copolymer of an aromatic fluxing oil and optionally bitumen at a temperature of 150 to 3000C in the presence of a gas containing elemental oxygen.  3 - Composition according to one of claims 1 and 2, characterized in that the rubberized bitumen is prepared by blowing a gas which contains elemental oxygen at a temperature of 150 to 3000C in a mixture of 23 to 88% ( relative to the total weight of the mixture) of a bituminous substance, 2 to 25% (based on the total weight of the mixture) of a copolymer of at least two mono-alpha olefins and a cyclic olefin having an endocyclic bridging and at least two olefinic double bonds, 10 to 75% (based on the total weight of the mixture) of a fluxing oil to elongate the copolymer, 0 to 4 parts by weight of sulfur per 100 parts by weight of the copolymer and 0 at 3% (based on the total weight of the mixture) of a polyolefin.  4 - Composition according to one of claims 1 and 2, characterized in that to prepare the rubber bitumen is mixed a bituminous substance, a copolymer of at least 2 mono-alpha olefins and a cyclic olefin having an endocyclic bridging and at least two olefinic double bonds, an aromatic fluxing oil and optionally sulfur, and then blowing into this mixture at a temperature of 150 to 2600C a gas containing elemental oxygen to form a concentrated concentrate which is dissolve in unfused bitumen.  5. Composition according to one of claims 1 to 4, characterized in that the mono-alpha olefins in the copolymer are ethylene and propylene, and the cyclic olefin is dicyclopentadiene or ethylidene-norborenene.  6 - Composition according to one of claims 1 to 5, characterized in that it contains the following ingredients (parts by weight) rubberized bitumen: 100 parts hardened extract: 4 to 40 parts particles of non-thermoplastic crosslinked rubber: 50-175 parts filler : 50-175 parts  7 - Composition according to claim 6, characterized in that it also contains 0.05 to 5 parts by weight of a long chain hydrocarbyl amine.  8 - Composition according to one of claims 1 to 7, characterized in that the weight ratio of the crosslinked non-thermoplastic rubber to the load is between 1: 1 and 3: 1.  9 - Composition according to one of claims 1 to 8, characterized in that it has a hardness of 30 to 60 on the IRHD scale and a rebound resilience lower than 20 96 at 25 C.  10 - Composition according to one of claims 1 to 9, characterized in that it has a permanent deformation after compression less than 20 do.  11 - Composition according to one of claims 1 to 10, characterized in that the non-thermoplastic crosslinked rubber is constituted by tire crumbs.