DE2631468A1 - METHOD FOR PRODUCING A BITUMINOUS MIXTURE AND ITS USE FOR SURFACE COATINGS - Google Patents

Description

SHELL INTERNATIONAL RESEARCH MAATSCHAPPIJ B.V. The Hague, Netherlands

"Process for the preparation of a bituminous mixture and its use for surface coatings".

claimed priority:

July 15, 1975, Great Britain, No. 29611/75

The present invention relates to a method for producing a bituminous mixture from a chemically modified one bituminous binder, a mineral aggregate and / or a filler. The invention also relates to the use of a such bituminous mixture for surface coatings.

It is known per se, surfaces with mixtures of bituminous To coat binders and a mineral aggregate and / or fillers. Such mixtures can be used directly as such be applied to a surface, and one speaks of einbaufbaren'Mischungen, or they can be applied to the The surface is self-made, and such mixtures are then referred to as being suitable for the soil mixing process. Such

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Measures are particularly useful for road construction, such as for the production of road surfaces, for hydraulic engineering, for erosion control and for the construction industry, for example for producing roof and floor coverings, and for sealing pipelines. Mixtures suitable for installation as well as mixtures suitable for soil mixing are usually produced, by mixing the components in question with one another at elevated temperatures in the range from, for example, 100 to 250.degree mixed, although lower operating temperatures can also be used, e.g. ambient temperature. As far as ready-to-install Mixtures for hot paving are to be prepared, the components in question are generally heated to one temperature preheated in the predetermined area before they are intimately mixed with one another. As far as mixes for The soil mixing process is usually only the bituminous binder to a temperature in the aforementioned Area preheated and then mixed with the mineral aggregate and / or filler located on the surface in question. Such measures using premixes or mixtures that can be built-in are described in the relevant literature discussed, for example in "Asfalt", published by the Vereniging voor Bitumineuze Werken (1973).

A wide variety of bituminous binders have already been combined with mineral aggregates and / or fillers, . to mix or mixes that can be installed in this way for the soil mixing process. In practice, however, is the selection of the binder component in general

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limited those binders which have a sufficiently low viscosity at the mixing temperature. For the production of puttable mixtures is such a low viscosity both for spraying or pumping in the relevant Binder in the mixing zone or mixing chamber of the mixing device in question as well as for good, intimate mixing Required in the mixing device with the mineral aggregate or filler.

In the case of. Mixtures for the soil mixing process is one low viscosity necessary so that the binder can be pumped or sprayed onto the surface. In general binders are considered unsuitable or unmanageable if the viscosity is at the relevant mixing temperature Exceeds 400 to 500 centistokes (cSt). Chemically modified bituminous binders are also very suitable per se for the aforementioned purpose, however, such modified binders have hitherto been used because of their very high viscosities has not yet been used on an industrial scale.

Surprisingly, it has now been found that it is also under Use of such highly viscous binders is possible to produce bituminous mixtures if you only take care that at least part of the binder in question is chemically modified only in situ in the presence of the aggregate and / or filler.

The inventive method for producing a bituminous

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Mixture of a chemically modified bituminous binder, a mineral aggregate and / or a filler is accordingly characterized in that the chemical modifier with at least part of the non-emulsified binder only while it is being mixed with the aggregate and / or Filler, brings to implementation. -.._- ■. . -.

The method according to the invention is particularly suitable for the production of mixable mixes, especially mixable mixes for hot paving, i.e. mixes, which are produced at elevated temperatures, for example in the temperature range from 100 to 250.degree. As far as mixtures to be produced for installation at ambient temperature, the bituminous binders in question can be in the form , a cut-off bitumen, i.e. a bitumen that has been diluted with a volatile solvent. Such However, cut-off bitumen is only used to a small extent, especially in road pits, because of its setting time sehr.lang is and also after the evaporation of the solvent remaining mixture does not have good physical properties. Those consisting of a cut bitumen Bituminous binders also do not always offer handling difficulties, even when made from a chemical modified bitumen. When using the method according to the invention, however, it is possible to

. - / less solvent than / than cut bitumen / ~ otherwise usual-

when doing the chemical modification in situ.

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Although any chemically modified bituminous binders and any mineral aggregates for the process according to the invention and / or fillers can be used as starting materials, it is particularly suitable for the production of Mixtures of chemically modified blown bituminous binders. In particular, chemically modified ones can be used for this purpose Fully blown bituminous binders are used as well as chemically modified, already malienic acid-modified ones bituminous binders and any mineral aggregates and / or fillers. ·

Blown eitumens are known per se, and they are either partially blown or fully blown bitumen. . Partially blown bitumens are produced by using a starting bitumen material, like gilsonite. or a directly distilled bitumen (distillate bitumen), at elevated temperatures up to Achieving a certain penetration value with air or Oxygen blows. Fully blown bitumen types, on the other hand, have a stronger viscoelasticity and are often produced as a result that a cut bitumen is produced from a partially blown bitumen by diluting it with a volatile solvent and then this cut bitumen from a partially blown raw material again at elevated temperatures with air or blowing oxygen.

Such blown bitumens can be made using chemical modifiers be reacted, for example with inorganic acids or organic acids or their anhydrides.

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For this purpose, e.g. hydrochloric acid, phosphoric acid, maleic acid or maleic anhydride, also alkali hydroxides such as sodium hydroxide, Potassium hydroxide or lithium hydroxide. Other suitable modifiers are organic or inorganic halides, such as aluminum, titanium or boron halides. Inorganic acids, such as phosphoric acid, and alkali hydroxides, such as potassium hydroxide, however, chemical modifiers are preferred according to the invention. The chemical modifier can be in one concentration in the range from 0.1 to 10 percent by weight, based on the amount of bituminous binder, can be used. Before the blown bitumen such chemical modification treatment is subjected, it can also be mixed with extenders and / or with polymeric substances.

Bituminous binders made by converting a starting bitumen such as gilsonite, directly distilled bitumen, propane bitumen

or blown bitumen either as such or in admixture with extenders and / or polymeric materials are, using, for example, 0.5 to 10 percent by weight of an olefinically unsaturated acid anhydride, such as maleic anhydride, or an olefinically unsaturated acid, such as maleic acid, are known per se. This kind of bituminous minerals is hereinafter referred to as maleic acid-modified bituminous binders for the sake of simplicity. The production of such maleic acid-modified bituminous binders from bitumen-polymer mixtures is already in progress has been proposed (see OS 25 13 514, published October 2, 1975). Polymeric substances suitable for this are ole-

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Finically unsaturated elastomers have molecular weights in the range from 100,000 to 500,000, such as styrene-butadiene copolymers. Such copolymers are commercially available, for example under the Designation "Cariflex" S 1712 and "Cariflex" S 1500. The polymeric substances can suitably be used in amounts below 10 percent by weight, based on the bituminous binder, can be used, with polymer concentrations in the range from 0.1 to 7.0 percent by weight are preferred.

Such maleic acid-modified bituminous binders, suitably having acid values in the range of about 0.01 to -2.0 Milliequivalent / gram, determined by titration, may have can be used very well as starting materials to be modified in the process according to the invention.

Such maleic acid-modified bituminous binders can be carried out according to the invention by means of ionic or covalent coupling Application of a suitable chemical modifier can be further modified. Suitable chemical modifiers for coupling with maleic acid-modified bituminous binders have already been proposed in OS 25 13 514 mentioned above. It's also been performing the Coupling reaction of emulsified maleic acid-modified bituminous Binding agents in the presence of a mineral aggregate and possibly other coupling agents in this earlier right has been proposed.

For the ionic coupling of maleic acid-modified bituminous

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Chemical modifiers suitable for sen starting binders are compounds of the metals of groups I to IV and in particular of subgroups IA to IVA of the Periodic Table of the Elements, such as compounds of lithium, sodium, potassium, calcium, Magnesium, barium, aluminum and lead. The hydroxides, alkoxides and salts of weak acids are very suitable for this purpose these metals. Lithium hydroxide is particularly suitable, Sodium hydroxide, potassium hydroxide and barium hydroxide as well as lead (II) acetate, Magnesium acetate, aluminum isopropoxide and / or aluminum sec-butoxide. The chemical modifier is preferably used as an aqueous solution or in liquid form in the Mixing temperature.

For the covalent coupling of a maleic acid-modified bituminous Chemical modifiers which are suitable as a binder as a starting material include esters, thioesters, amide groups or capable of forming imide groups. Such groups are formed when organic compounds with at least two functional groups are used which are bound to the maleic acid-modified bituminous binder groups can react. Suitable functional groups in such chemical modifiers are the hydroxyl group, the Mercapto group, the amino group and the N-hydrocarbylamino group as well as the epoxy group such as an epoxyalkyl group and isocyanate groups. Examples of suitable chemical modifiers are ethylene glycol, diethylene glycol, 1,4-butanediol, Glycerine, trimethylolpropane, the diglycidyl ester of bisphenol A, Methylenediphenyl-4,4-diisocyanate, tolylene-di-isocyanate,

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Triethylenetriamine, tetraethylene pentamine and diethanolamine.

For the coupling of maleic acid-modified bituminous binders used as starting material, the modifiers are used used in amounts of 28 to 500 percent by weight of that amount which is required to be stoichiometric to react with the binding agent in question, i.e. to neutralize it. The chemical modifier is preferred in concentrations of 50 to 300 percent by weight and in particular from 75 to 200 percent by weight, based on the theoretically required amount, used. That as the starting material Maleic acid-modified bituminous binders used can also be mixed with extenders before the chemical modification and / or polymeric substances are mixed.

The method according to the invention is particularly suitable for producing mixtures of chemically modified blown bituminous binders or again chemically modified already maleic acid-modified bituminous binders with Mineral aggregates and / or fillers. This is due to the fact that although blown bituminous binders and maleic acid modified blown bituminous binders, especially if less than 10 percent by weight maleic anhydride for their production has been used, at the usual mixing temperatures, viscosities below the stated limit of 400 to 500 cSt and are therefore easy to handle per se, but that the chemically modified blown bituminous binders and the again chemically modified, already

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acid-modified bituminous binder viscosities well over 400 to 500 cSt and usually even over 1000 cSt the usual mixing temperatures on iron and therefore practical are unmanageable and difficult to mix.

However, the method according to the invention is not limited to mixtures which are made by means of chemically modified bituminous Binders of the type mentioned above have been obtained. For example, by means of the method according to the invention also produce a maleic acid-modified bituminous binder with a high acid content. As stated above, using less than 10 percent by weight Maleic anhydride produced maleic acid-modified bituminous binders at the mixing temperature usually Viscosities below 500 cSt, but if maleic anhydride quantities for the manufacture of, for example, above 20 percent by weight are used, then the obtained can Binder have such a high viscosity that it can no longer be handled. The inventive method can therefore serve to chemically produce a starting bitumen, for example a distillate bitumen, by means of maleic acid or maleic anhydride to modify or an already maleic acid-modified bituminous starting binder can be further mixed with maleic acid or modified with maleic anhydride.

A customary mineral aggregate or a customary filler can be used for the process according to the invention. Suitable mineral aggregates are, for example, gravel , bauxite, granite,

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Sandstone, basalt, porphyry, dolomite, slag and limestone. Suitable fillers consist, for example, of limestone, sand, Asbestos and / or fiberglass. In general, the mineral aggregates are particles that cannot pass through a sieve with a Mesh sizes of 75 microns go, while fillers generally have a particle size such that they can pass through a Pass a sieve with a mesh size of 75 microns through it. In general, the proportion of mineral aggregate in the invention is preparable mixtures 10 to 5000 percent by weight, based on the homogeneous bituminous binder.

For the production of mixes that can be built-in, the three Starting components, i.e. the bituminous binder, the mine ral unit and / or the filler and the chemical modifier are fed separately into the mixing zone. It is but also possible, first the mineral aggregate and / or the filler with the chemical modifier or the Mix bituminous binder. It is advantageous not to feed the chemical modifier into the mixing zone until if the bituminous binder and the mineral aggregate and / or the filler have been together for a certain period of time have been premixed.

The invention is illustrated by the following examples. In these examples, the viscosities given are in accordance with according to ASTM D-2170 using a capillary viscometer. The penetration values are according to the ASTM regulation D-5 has been measured (25 C, 0.1 mm), and the softening points

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have been determined in C by the ring and ball method. The Marshall test is according to ASTM D-1559 a compression carried out at 160 C.

example 1

Production of a maleic acid-modified bituminous binder.

1000 g of a fully blown Kuwait bitumen (penetration 40, softening point 85 C) are mixed with 200 g of an aromatic oil extract (Dutrex 729 HP) mixed and thereby stretched. This mixture is then heated to 175 ° C and then become 24 g (2 percent by weight) of maleic anhydride were added and this mixture was stirred for a further 2 hours on a Maintained temperature of 170 to 180 C. The homogeneous product produced in this way has a viscosity of 175 cSt and a viscosity at 190 ° C Acid value of 0.23 milliequivalent / g.

At spie 12 (comparison test)

1200 g of the maleic acid-modified bituminous binder produced according to Example 1 are heated to 160 to 180.degree. 15 g of potassium hydroxide are then added with stirring. The temperature is held in the range of for half an hour to two hours 160 to 180 ° C. The viscosity of the chemically modified one thus obtained Product is so high that it cannot be determined, and one cannot find this product in a usual one Process hot mixing device.

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Example 3

66 g of the modified maleic acid prepared according to Example I. bituminous binder are placed in the mixing zone of a laboratory hot mixer at a temperature of 175 to 180 ° C pumped in, and at the same time separately 1200 g of a conventional road construction mineral aggregate are added, which to 55 percent by weight of stones with a particle size of 0.2 to 1.8 cm, 35 percent of sand with a particle size of 2 mm and 10 percent of filler with a particle size smaller than 64 u. Then 1.0 g of potassium hydroxide as an aqueous solution- added to the mixture, and one continues mixing for another minute. In this paved mix is a chemically modified bituminous Binder intimately associated with the mineral aggregate and shows excellent processing properties including one good compressibility. The data obtained from the Marshall test are summarized in Table I below.

Example 4

Production of a maleic acid-modified bituminous binder.

The procedure of Example 1 is followed using a half-blown Kuwait bitumen repeated (penetration 80 to 100, the data of the Marshall test are summarized in Table I) . 48 g of maleic anhydride (4 percent by weight) are also used here. The homogeneous product obtained in this way has a viscosity of about 109 cSt at 190 ° C and an acid value of about 0.40 milliequivalents / g.

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Example 5 (comparative experiment)

The procedure of Example 2 is carried out using 1200 g of the maleic acid-modified bituminous produced according to Example 4 Binder and with the addition of 34 g of the diglycidyl ether of bisphenol A repeated. The product thus obtained has at 190 ° C a viscosity of 1800 cSt, and it is not possible to use this binder in a conventional hot mixer to process.

Example6

The procedure of Example 3 is modified using 66 g of the maleic acid prepared according to Example 4 bituminous binder and 1.9 g of diglycidyl ether of Bisphenol A repeated. In this case, however, the hot-installable mixture of chemically modified bituminous Binder and mineral aggregate have excellent properties and good compressibility. The corresponding values of the " Marshall tests are listed in Table I. Corresponding results are achieved if potassium hydroxide is used instead of the Diglycidyl ethers of bisphenol A as a chemical modifier used.

Example 7

Production of a maleic acid-modified bituminous binder.

The procedure of Example 1 is repeated using a bitumen with a penetration of 80 to 100, which

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has been produced by blending 565 g of an Iran propane bitumen with 6 35 g of an Iran Short Residue ", with also 4 percent by weight of a styrene-butadiene rubber are added (commercial product "Cariflex" S-1500). There are 24 g (2 percent by weight) maleic anhydride reacted with the starting bitumen. The homogeneous end product obtained in this way is at 190.degree a viscosity of 200 cSt and an acid value of 0.17 milliequivalent /G.

Examples 8 and 9 (comparative experiments)

The procedure of Example 2 is modified using 1200 g of the maleic acid-modified prepared according to Example 7 bituminous binder and of 26.9 g of KOH (Example 8) or of 39.3 g of aluminum sec-butoxide (Example 9J repeated. The The products obtained in this way have such a high viscosity that it cannot be determined, and the bituminous in question Binders cannot be used in a conventional hot mixing apparatus either are processed.

Examples 10 and 11

The procedure of Example 3 is modified using 66 g of the maleic acid prepared according to Example 7 bituminous binder and of 1.5 g of KOH (example 10) or of 2.2 g of aluminum sec-butoxide (example 11). the thus obtained buildable mixtures, which the chemically modified bituminous binder and a mineral aggregate contain excellent properties and are easy to compress. The experimental data obtained from the Marshall test

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are given in Table I below.

Example 12 (comparative experiment)

The procedure of Example 2 is carried out using 1200 g of a homogeneous, fully blown Kuwait bitumen (penetration 40, softening point 88 ° C, viscosity at 190 ° C: 300 cSt) and of 12 g of KOH repeated. The product thus obtained has a very high viscosity and cannot be processed in a conventional hot mixer.

Example 13 "

The procedure of Example 3 is followed using 66 grams of the fully blown Kuwait bitumen described in Example 12 and repeated by 0.7 g of KOH. The thus obtained buildable mixture of a chemically modified bituminous Binder and mineral aggregate has excellent properties and good compressibility. The ones obtained from the Marshall test Data are summarized in Table I below. Corresponding favorable results are achieved if one takes place used by KOH phosphoric acid as a chemical modifier.

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Table I 2 *

example P _M (kN) F _M (mm) ^Q M ⁽ V ^P M ^J *
Kuwait 80/100 3 ^Γ * 6.7 4.8 1.4 3. 11.3 2.1 6.3 6th 14.2 4.1 3.5 10. 11.5 3.9 3.0 11. .12.2 3.3 3.7 13th 15.6 3.1 5.0 1 stability 2 * flow value

3 see example 4

Claims

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Claims (13)

- ie - 263-468 Claims | lJ process for the production of a bituminous mixture from a chemically modified bituminous binder, a mineral aggregate and / or a filler / characterized, that the chemical modifier with at least a portion of the non-emulsified binder only during mixing the same with the unit and / or filler to implement. 2. The method according to claim 1, characterized in that the mixture is prepared prior to application to a surface. 3. The method according to claim 1 and 2, characterized in that the mixture using a temperature in the range from 100 to 25O ° C. 4. The method according to claim 1 to 3, characterized in that the binder in the modified state at the mixing temperature has a viscosity greater than 400 to 500 cSt. 5. The method according to claim 1 to 4, characterized in that a blown bitumen is modified *. 6. The method according to claim 5, characterized in that 0.1 to 10 percent by weight of the modifying agent, based - 19 - 2631463 on the non-emulsified binder. 7. The method according to claim 5 or 6, characterized in that an inorganic acid or an alkali hydroxide as a modifying agent can be used. 8. The method according to claim 1 to 4, characterized in that one by reacting a mixture of bitumen and one
Polymer obtained with maleic anhydride, non-emulsified binder is used as the starting material. 9.. Method according to claim 8, characterized in that
the modifier is applied at a concentration of 75 percent to percent of the amount required to react with the non-emulsified binder. 10. The method according to claim 8 and 9, characterized in that a hydroxide or alkoxide is used as a modifying agent
Metal of groups I to IV of the periodic table of the elements
is used. 11. The method according to claim 8 and 9, characterized in that an organic compound is used as a modifying agent
at least two functional groups are used which are suitable for reaction with groups of the non-emulsified binder. 12. The method according to claim 1 to 11, characterized in that 609885/1054 that mineral aggregate and / or filler in an amount of 10 to 5000 percent by weight, based on non-emulsified binder, be applied. 13. Use of the bituminous produced according to claims 1 to 12 Mixture for surface coatings. G0.5-8L8.E - / - 10i4