Modifier for bitumen, bitumen-containing binder, and bitumen-containing substances and materials

Abstract

The invention relates to a modifier (4) for bitumen (5) or bitumen-containing materials, in particular for bitumen-containing binders for bridge, tunnel or road construction. The modifier (4) comprises microspheres (1), wherein the microspheres (1) are made from a rigid elastic material. The invention also relates to a bitumen (5), a bitumen-containing material, in particular a binder, referred to as a bitumen-containing material, a bridge surface or road surface comprising bitumen (5) or bitumen-containing binder, wherein in each case a modifier (4) having elastic polymer microspheres (1) is present.

Description

[0001] MODIFIER for BITUMEN, BITUMEN-CONTAINING BINDER and BITUMEN-CONTAINING SUBSTANCES and MATERIALS

[0002] FIELD OF THE INVENTION

[0003] The invention relates to a modifier for bitumen or bitumen-containing materials according to the preamble of claim 1. The modifier can be used in construction, for example for bitumen and bitumen-containing binders for road construction. Furthermore, the modifier can be used for modifying bituminous materials, for example for asphalts, for sealing, vibration, oscillation and thermal insulation and / or corrosion protection, for example in bridges, road infrastructure and other structures. According to the preamble of claim 12, the invention also relates to a method for producing a modifier, in particular as described herein.

[0004] The invention also relates to a (road construction) bitumen according to the preamble of claim 13 and a (road construction) binder, in particular containing bitumen, according to the preamble of claim 14.

[0005] The invention further relates to an (asphalt) road surface according to the preamble of claim 15.

[0006] Furthermore, the invention relates to a method for producing a road surface, particularly described herein, according to the preamble of claim 16.

[0007] Finally, according to claim 20, the invention relates to a use of elastic microspheres, in particular elastic microspheres that comprise at least one polymer or are formed from at least one polymer. Microspheres are small, particularly elastic, hollow spheres.

[0008] TECHNOLOGICAL BACKGROUND

[0009] Bitumen and bituminous binders are widely used, particularly in road construction. Asphalt, for example, is made from rock flour (filler), fine and coarse aggregates, and a binder, such as bitumen. The properties of the asphalt are adapted to the specifications and local conditions by adding binder modifiers. Bitumen is modified for asphalt production using the "dry process," i.e., by directly mixing the asphalt mixture with bitumen and modifier in a mixer, or the "wet process," i.e., by pre-modifying the bitumen.

[0010] Modifiers can be used to specifically influence the physical, rheological, and chemical properties of binders and their parameters for use in bridge and road construction, particularly the properties of the road surface, such as elasticity, heat resistance, water resistance, as well as mechanical, acoustic, and structural properties. Ideally, the parameters should be adjusted as needed.

[0011] PRESENTATION OF THE INVENTION

[0012] The invention is based on the object of optimizing the properties of a bitumen material, in particular bridge or road surface, such that as many physical, rheological and / or technical parameters as possible can be adapted as needed. This object is achieved by a modifier according to claim 1. Accordingly, it is provided that the modifier comprises microspheres, wherein the microspheres or the wall of the microspheres or a wall layer of the wall of the microspheres are formed from a robust, solid, elastic, in particular permanently elastic, in particular organic, material. Microspheres are hollow, namely small hollow spheres (hollow spheres), or balls with one or more shells made of the same or different materials and an interior space. The interior space can contain an inner material, for example a gas or gas mixture.The microspheres or the wall of the microspheres or a wall layer of the microspheres can comprise or be formed from a polymer, for example polyacrylonitrile (PAN). A modifier with polymer microspheres can be used in bituminous materials and products, in particular in asphalt, in jointing materials, in waterproofing materials and in other materials. The modifier can be used to produce a sealing layer in the waterproofing structure on concrete, steel or asphalt surfaces. The incompletely expanded microspheres have improved strength and / or elastic properties, whereby the bitumen and asphalt in which they are used significantly improves their consumer properties. By composing microspheres from specific materials, of specific sizes, if necessarydifferent sizes, and from certain geometric and structural properties, certain properties of the binder and thus also of the road surface can be adapted as required. The modifier according to the invention results in a multitude of advantages: The modifier can be used for the "dry processes" and "measurement processes" mentioned above. Such a modifier with polymer microspheres can be used in bituminous materials and products, in particular in asphalt, also in crushed stone mastic asphalt, in materials for preparing the concrete surface for asphalting, for example for bridge construction and renovation, for joint sealing, in sealing materials or in other construction materials. When used in a binder for road construction, a higher elasticity of the binder and thus also of the surface is achieved. Furthermore, better mixing of the materials of the surface is achieved during its production.A typical asphalt concrete mix production plant with an average capacity of approximately 150 to 200 tons per hour, for example, has a single batch of approximately 2,500 to 3,000 kg of mix. The bitumen binder content can range from approximately 125 to 150 kg, or approximately 5%, for example, with the remainder being natural, very solid rock particles with a grain size of up to 20 mm. The intensive mixing time is approximately 30 to 45 seconds. Less robust microspheres made of non-elastic or less elastic materials, such as glass or ceramic, are not suitable for withstanding the high mechanical stresses encountered during the mixing process. The modifier described and claimed herein, on the other hand, comprises such elastic and robust microspheres that they are easily capable of withstanding the high mechanical stresses encountered during the mixing process.

[0013] The elastic microspheres also provide a vibration-reducing and / or shock-absorbing effect in the binder, thereby preventing cracking or the formation of ruts in the surface of a (road) pavement. This is particularly important during the construction and rehabilitation of bridges or tunnels. The proportion of microspheres in the binder can preferably be about 0.01% to about 10%, or about 0.01 wt% to about 10 wt%, or about 0.01 vol% to about 10 vol%. For standard road construction bitumen, an addition of between about 0.05% to about 8%, or about 0.05 wt% to about 8 wt%, or about 0.05 vol% to about 8 vol% can be provided. The polymer microspheres result in a higher volume of the binder while simultaneously reducing its weight. The specific gravity of polymer microspheres is preferably about 15 kg / m 3 up to about 30 kg / m 3In this respect, material savings are achieved due to the lower density of the binder without changing the other properties of the material.

[0014] The elastic microspheres act as a damping agent and improve the mixability of the road construction material. Furthermore, mixing time is reduced because the microspheres reduce internal friction. For example, the measures described here achieve a mixing time reduction of approximately 3% to approximately 8%. Microspheres act as a lubricant or mechanical (ball) bearing for the pavement components. The service life of the road surface is extended, particularly due to the damping effect of the elastic microspheres. Polymer microspheres act as elastic buffers or shock absorbers in an asphalt matrix. Aging effects are inhibited and / or reduced, and the elasticity of bitumen, which typically decreases over time, is maintained for longer. Furthermore, the viscosity of the bitumen can be reduced.

[0015] The polymer microspheres in the binder, in certain compositions, reduce noise, vibration, or sound (desired, for example, in so-called "whisper asphalt"). Other compositions can reduce the water absorption of the binder / paving. They also improve its rigidity. The modifier also improves the adhesion of bitumen / asphalt to concrete. This is particularly important in the construction and rehabilitation of bridges or tunnels.

[0016] The user can use a composition of (different) microspheres and / or a composition of a mixture of polymer microspheres with different degrees of openness, resulting in a gradual and / or time-dependent and / or temperature-dependent opening of the polymer microspheres in the overall system ("4D effect"). In this way, the elasticity and / or fatigue resistance, especially of asphalt, can be maintained over a long period of time, even over its entire service life.

[0017] According to a modifier variant, it can be provided that the microspheres, in particular the wall of the microspheres, are expandable, wherein the microspheres are incompletely expanded in the modifier.

[0018] According to a preferred embodiment, the microspheres or the wall of the microspheres or a wall layer of the wall of the microspheres can comprise at least one polymer or be formed from at least one polymer, e.g., polyacrylonitrile (PAN). A plastic composite or plastic compound can be provided. The wall / shell of the microspheres can be formed in multiple layers. Polymer microspheres are characterized by high strength and high elasticity. This makes them highly resistant to material fatigue. Compared to "standard modifiers" (e.g., with polypropylene components), the polymer microspheres, e.g., based on polyacrylonitrile (PAN), can withstand a very high number of compression and expansion cycles without damage, which is of fundamental importance for road construction materials that must remain stable under changing and cyclic loads for as long as possible.It may be advantageous for the microspheres to exhibit thermoplastic and / or elastic properties. During an expansion phase (e.g., thermally induced), the microspheres may exhibit thermoplastic properties, and after expansion, the microspheres may exhibit elastic properties.

[0019] According to a preferred variant, the microspheres contain at least one gas or a gas mixture. The inner material or filling of the hollow, spherical microspheres can thus be formed from a gas or gas mixture. Upon external pressure, the elastic shell of the microspheres can deform without losing its elastic properties. When the bitumen mixture is exposed to the user-adjustable and controllable external temperature range, the gas contained in the microspheres expands, the elastic wall / shell of the polymer microspheres softens, and the polymer microspheres expand to the required diameter-to-wall-thickness ratio, thus achieving the required strength and size.

[0020] Preferably, the microspheres have a diameter in a diameter range between about 5 pm and about 300 pm.

[0021] In particular, for the purpose of density reduction, the microspheres (immersed in bitumen) can be designed to expand upon heating, particularly so that the expanded microspheres have a diameter that is several times the original diameter, or almost the same. Upon heating, the gas expands and the shell softens, causing the microsphere to expand, i.e., its volume increases. This reduces the density of the material. The density reduction can occur by a factor of about 100, for example, by about 1,100 kg / m³. 3 to only about 15 kg / m 3 The microspheres used in the modifier can withstand temperatures ranging from approximately 200°C to approximately 250°C, depending on the shell structure. Furthermore, the expanded polymer microsphere can be easily flattened without loss of elastic and strength properties.

[0022] Preferably, the modifier, in particular as a carrier and / or as a distribution aid, may comprise at least one additive and / or at least one porous material, wherein the porous material preferably has a specific surface area greater than approximately 0.1 m 2 / g. The additive and / or the carrier may comprise rubber and / or a fiber material or be formed from rubber and / or a fiber material (as a similarly porous material). Rubber powder obtained from scrap tires can preferably be used as a carrier for the modifier. Such a rubber powder with a large specific surface area (more than 0.1 m 2 / g) not only acts as a carrier for polymer microspheres, but also creates a synergistic effect due to its sorption properties (temporary binding of maltenes and asphaltenes of the bitumen), enhancing the effectiveness of polymer microspheres. The particle size of the additive can range between approximately 0.2 mm and approximately 7 mm. Rubber particles and / or fibers of the additive can be at least partially devulcanized and / or formed from a material obtained, for example, from used tires.

[0023] Optimizing the properties of a bitumen material, in particular a bridge or road surface, so that as many physical, rheological, and / or technical parameters as possible can be adapted as needed is further achieved with a modifier production method according to claim 12. In particular, a modifier as described herein is produced in the method. At least one single- or multi-screw extruder is used, with rubber being partially devulcanized as a carrier, thereby making the microspheres more adaptable to the carrier.

[0024] Optimizing the properties of a bitumen material, in particular bridge or road surface, so that as many physical, rheological and / or technical parameters as possible can be adapted as required is further achieved with a bitumen according to claim 13. The bitumen is characterized in that it comprises a modifier described herein.

[0025] Optimizing the properties of a bitumen material, in particular a bridge or road surface, so that as many physical, rheological and / or technical parameters as possible can be adapted as required, is also achieved with a binder, in particular a bitumen-containing binder, according to claim 14. The binder is characterized in that it comprises a modifier described herein.

[0026] Optimizing the properties of a bitumen material, in particular a bridge or road surface, so that as many physical, rheological, and / or technical parameters as possible can be adapted as needed is further achieved with a road surface according to claim 15. The road surface accordingly comprises a bitumen as described herein or a binder, in particular a bitumen-containing one, as described herein. The bitumen content in the surface can be between approximately 3% and approximately 8%.

[0027] Optimizing the properties of a bitumen material, in particular a bridge or road surface, so that as many physical, rheological, and / or technical parameters as possible can be adapted as needed is further achieved with a manufacturing method according to claim 16. The method serves to produce a road surface described herein, using a bitumen and / or a binder described herein. Preferably, the bitumen or the binder can be heated, in particular to adjust the size and / or properties of the microspheres.

[0028] It can be provided, particularly in the wet process described above, that the incomplete expansion of the microspheres during introduction into the bitumen takes place at a temperature that is approximately 10% lower or more than 10% lower than the temperature at which complete expansion of the microspheres would occur. The incomplete expansion of the microspheres can take place in a tank, in particular in a bitumen storage and heating tank, wherein a mixing device, in particular a paddle mixer, is arranged in the tank. In this case, mixing with rubber powder can take place simultaneously with the expansion of the microspheres in the bitumen storage and heating tank. For this purpose, the rubber powder with a fraction of approximately 0.5 mm can be used. In this case, a modifier containing microspheres and rubber powder can be introduced into the bitumen in a ratio of up to approximately 9 to 1 in order to obtain masterbatches.

[0029] Optimizing the properties of a bitumen material, in particular a bridge or road surface, so that as many physical, rheological, and / or technical parameters as possible can be adapted as needed is finally achieved according to claim 20 by using elastic (polymer) microspheres or microspheres that comprise or are formed from polyacrylonitrile, or whose wall / shell comprises or is formed from polyacrylonitrile. The elastic microspheres are used as a modifier or modifier component, in particular of a modifier with the features described herein, for bitumen or bituminous material, in particular for bridge or road construction. Preferably, the bitumen or binder should be heated to at least a temperature at which the polymer microspheres expand at least threefold.

[0030] The aforementioned components to be used according to the invention, as well as those claimed and described in the exemplary embodiments, are not subject to any special exceptional conditions in terms of their size, shape, material selection and technical conception, so that the selection criteria known in the field of application can be applied without restriction.

[0031] Further details, features, and advantages of the subject matter of the invention emerge from the dependent claims, as well as from the following description and the accompanying drawing, which schematically illustrates, by way of example, an embodiment of the use of polymer microspheres. Individual features of the claims or embodiments can also be combined with other features of other claims and embodiments.

[0032] BRIEF DESCRIPTION OF THE CHARACTERS

[0033] In the drawing show

[0034] Fig. 1 Polymer microspheres in schematic representation,

[0035] Fig. 2 a bitumen matrix with microsphere modifier in schematic representation and

[0036] Fig. 3 shows an asphalt matrix with a modified bitumen in a schematic cross-sectional view. DETAILED DESCRIPTION OF EMBODIMENTS

[0037] A schematic representation of elastic polymer microspheres 1 is shown in Fig. 1. Microspheres for the applications described herein are highly elastic, acid- and alkali-resistant, hollow polymer spheres and / or PAN spheres, which, according to one variant, can be filled with a special gas that expands upon heating during the modification of the bitumen, thereby acquiring the strength and geometric dimensions required for the respective application. The strength and elasticity of the microspheres can depend on the nature of the wall thickness and / or the volume of the microsphere. The small, unexpanded microsphere 1 on the left edge of Fig. 1 has a small volume at normal temperature and pressure. As the temperature increases (symbolized by the arrow at the bottom edge of the image), the volume of microsphere 1 increases.The elastic microsphere 1 expands, with the wall thickness of the shell 2 decreasing with increasing temperature. A maximally expanded microsphere 1 can be seen on the right edge of Fig. 1. The shell 2 can comprise or be formed from a polymer. The shell 2 can be formed in multiple layers. The shell 2 and / or a shell layer can be formed from a plastic compound. The microspheres 1 can have a filling 3 made of a gas or gas mixture.

[0038] The microspheres 1 shown schematically in Fig. 1 can be incorporated into a bitumen matrix as a modifier 4 or modifier component, for example by blending or mixing. A bitumen matrix is ​​shown in Fig. 2, which schematically shows the volumetric distribution of the microspheres 1 in the bitumen 5. The microspheres 1 have different expansion rates depending on the temperature. The bitumen 5 can optionally be modified with a microsphere composition, whereby the microsphere composition can comprise microspheres 1 of different sizes and / or different (gas) fillings 3 and / or different nature / composition of the shell 2. Within the bitumen matrix, the microspheres 1 have, among other things, the function of an elastic buffer or shock absorber.Mechanical impacts on the bitumen 5 during its use as an asphalt mixture in the road surface (asphalt 7) can be absorbed by the damping microspheres 1 and make the material less susceptible to cracking or other structural defects and defects.

[0039] The binder (bitumen 5) shown in Fig. 2 can contain, in addition to the polymer microspheres, one or more modifier additives, such as porous materials, in particular as carriers for the microspheres 1. Rubber materials can be used to produce the additive. Various types of vulcanized and / or partially devulcanized rubber, for example in powder and / or granulate form, can be provided. Various types of pretreated rubber waste products, including scrap tires based on synthetic and natural rubber compounds, are also suitable. Ideally, the rubber materials have the largest possible specific surface area (0.1 m 2 / g). These can be provided by technical grinding processes, for example, using (single-, twin-, or multi-screw) extruders. This can also be achieved by technical comminution processes using cutting mills, rolling mills, and granulators.

[0040] The volumetric distribution of polymer microspheres 1 in an asphalt matrix is ​​schematically shown in Fig. 3. The asphalt 7 comprises rock material with many rock elements 6 and a binder, for example, bitumen 5. The binder comprises a modifier 4, which in turn comprises plastic microspheres 1. The elastic microspheres 1 form a kind of ball-bearing effect in the asphalt material, or buffering agent, for the rock elements 6. The physical, rheological, chemical, and geometric properties of the plastic microspheres 1 or microsphere composition in the binder modify the quality and technical parameters of the asphalt 7, such as its flexibility, adhesion properties, water resistance, heat resistance, density, porosity, acoustic properties, processability, recyclability, vibration properties, etc.Systematic investigations by the applicant have shown that when bridge or road construction bitumen 5 is modified with additized polymer microspheres 1 and rubber / rubber carriers (in particular from used tires), the bitumen properties exhibit significant improvements: accordingly, the following were observed for microsphere-enriched bitumen 5: a reduction in needle penetration, an increase in the softening point (ring and ball), an increase in elastic recovery, an increase in the complex shear modulus in the high service temperature range, and an ageing-inhibiting effect (according to thin film test oven tests: Rolling Thin Film Oven, RTFOT ageing).

[0041] LIST OF REFERENCE SYMBOLS

[0042] 1 microsphere

[0043] 2 wall / shell

[0044] 3 Filling

[0045] 4 Modifier

[0046] 5 Bitumen

[0047] 6 Rock Element

[0048] 7 Asphalt

Claims

CLAIMS 1. Modifier (4) for bitumen (5) or bitumen-containing materials, in particular for bitumen-containing binders for bridge, tunnel or road construction, characterized in that the modifier (4) comprises microspheres (1), wherein the microspheres (1) or the wall of the microspheres (1) or a wall layer of the wall of the microspheres (1) is / are formed from a solid elastic, in particular permanently elastic, material.

2. Modifier (4) according to claim 1, characterized in that the microspheres (1), in particular the wall of the microspheres (1), are expandable, wherein the microspheres (1) in the modifier are incompletely expanded.

3. Modifier (4) according to claim 1 or 2, characterized in that the microspheres (1) or the wall of the microspheres (1) or a wall layer of the wall of the microspheres (1) comprise at least one polymer or are / is formed from at least one polymer.

4. Modifier (4) according to one of claims 1 to 3, characterized in that the microspheres (1) or the wall of the microspheres (1) or a wall layer of the wall of the microspheres (1) comprises polyacrylonitrile or is formed from polyacrylonitrile.

5. Modifier (4) according to one of claims 1 to 4, characterized in that the microspheres (1) have thermoplastic and / or elastic properties.

6. Modifier (4) according to one of claims 1 to 5, characterized in that the microspheres (1) contain at least one gas or a gas mixture.

7. Modifier (4) according to one of claims 1 to 6, characterized in that the microspheres (1) have a diameter in a diameter range between about 5 pm and about 300 pm.

8. Modifier (4) according to one of claims 1 to 7, characterized in that the microspheres (1) expand upon heating, in particular such that the expanded microspheres (1) have a diameter which corresponds to or almost corresponds to a multiple of the original diameter.

9. Modifier (4) according to one of claims 1 to 8, characterized in that the modifier (4), in particular as a carrier, comprises at least one additive and / or at least one porous material, wherein the porous material preferably has a specific surface area which is greater than approximately 0.1 m 2 / g is.

10. Modifier (4) according to claim 9, characterized in that the additive and / or the porous material, in particular the carrier, comprises / comprises rubber and / or a fiber material or is / are formed from rubber and / or a fiber material.

11. Modifier (4) according to claim 10, characterized in that the rubber, in particular the carrier means, is at least partially devulcanized and / or is formed from a material obtained from old tires.

12. A method for producing a modifier, in particular a modifier according to one of claims 1 to 11, characterized in that at least one single-screw or multi-screw extruder is used, wherein rubber is partially devulcanized as a carrier, whereby the microspheres become better adaptable to the carrier.

13. Bitumen (5), in particular for bridge, tunnel or road construction, characterized by a modifier (4) according to one of claims 1 to 11.

14. Binder, in particular bitumen-containing binder, in particular for bridge, tunnel or road construction, characterized by a modifier (4) according to one of claims 1 to 11.

15. Bridge or road surface, in particular asphalt (7), characterized in that the bridge or road surface, in particular the asphalt (7), comprises a bitumen (5) according to claim 13 and / or a binder according to claim 14.

16. A method for producing a bridge or road surface, in particular a bridge or road surface according to claim 15, characterized in that a bitumen according to claim 13 is used and / or a binder according to claim 14.

17. The method according to claim 16, characterized in that the bitumen and / or the binder are heated, in particular to adapt the size and / or properties of the microspheres.

18. A method according to claim 16 or 17, characterized in that the incomplete expansion of the microspheres during introduction into the bitumen takes place at a temperature which is approximately 10% lower or more than 10% lower than the temperature at which a complete expansion of the microspheres would take place.

19. Method according to one of claims 16 to 18, characterized in that the incomplete expansion of the microspheres takes place in a tank, in particular in a bitumen storage and heating tank, wherein a mixing device, in particular a paddle mixer, is arranged in the tank.

0. Use of elastic microspheres (1) or of elastic microspheres (1) comprising at least one polymer or formed from at least one polymer, or of microspheres comprising polyacrylonitrile or formed therefrom, as a modifier (4) for bitumen (5) or bitumen-containing material, in particular for bridge or road construction, in particular as a modifier having the features according to one of claims 1 to 11.

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