DE1945481A1 - Stabilised bitumen for water-repellent - comps - Google Patents

Abstract

Bitumen compositions for binders, layers or film applied to acidic building aggregates used in underground constructions, for bulkheads or roads, made by either mixing into the bitumen a non-extending, water-repellent oil (silicone or paraffin oil) or a clay (montmorillonite, illite, kaolin) with a molecular sieve character or alternatively by applying Fe formate to the aggregate, converting it by heating during mixing to Fe2O3 when the oxide on the surface will strongly bind the applied bitumen to the surface. Such bitumen coatings have good water repellency and good adhesion.

Description

Process for the production of dry and water-repellent bitumen The invention relates to the production of bitumen distilled from petroleum, Bitumen binders, bitumen layers and bitumen films, with the addition of solid and liquid substances.

The adhesive strength of bituminous binders, layers and films or the binding agent bitumen obtained by distillation of the petroleum in particular on acidic rock with a relatively high silicon content, for example on quartzite (quartzite chippings) is in many cases insufficient to achieve a durable bond, in which bitumen or stone was tested for adhesive strength according to DIN 1995 and primarily insofar as the bitumen or its bond, in particular to acidic, is insufficient Rock becomes permeable to water after a short period of use and thereby separates itself from rock replaces.

The object of the invention is disadvantageous for rock formation Bitumen and stone for civil engineering, especially sheet piling and road construction make usable eu To ensure both a safe and a better adhesion of under Water exposure to standing bitumen, especially on acidic rock with a high silicon content To achieve (quartzite), the crosslinking is based on amino groups Known adhesive agents; but they only prevent the bitumen film from contracting (Stripping); however, bituminous substances and mixtures of this type have the disadvantage high temperature sensitivity and low resistance due to premature aging. Also is ea known from the addition of tar oils, the passage speed to reduce the water, but without being able to prevent its passage, so that the bitumen or bitumen film detachment takes place in a relatively short time.

The invention is based on the observation that the regular about 1% part by weight of water in the bitumen in the case of a relatively thin bitumen paint or bitumen film, also the crystallization cavity and the polarizability of the bitumen molecules contribute significantly to the harmful water permeability.

The invention relates to a process for the production of bitumen, Bitumen binders, bitumen layers and the bitumen film as a finishing agent Addition of oils and fillers, in which water impermeability and appropriate Increasing the usefulness and service life is achieved in that the bitumen molecules either by adding non-spreading, water-repellent oils electrostatically or by the addition of two-dimensional molecular sieve forming substances, for example Iron formate for the formation of Fe2 O3 or through three-dimensional molecular sieves Substances, for example clays, are mechanically stabilized.

To prevent possible water migration or

the migration of water molecules through crystallization cavities in the Bitumen and the temperature and time-dependent solubility of bitumen at water interfaces the bitumen is here according to the invention for the first time in a high-performance mixer with a non-spreading oil, for example silicone oil, paraffin oil, for higher degrees Distribution mixed, which means that even the smallest crystallization cavities are later filled can be the non-spreading oil, for example silicone oil or paraffin oil still a moderate flow during the Has test temperature and higher evaporation temperature than the bitumen processing temperature of approx. 140 until 20,000 has. The surface tension of these non-spreading, water-insoluble ones Oils, especially silicone and liquid paraffin, that meet this condition, has to der.des interfacial or surface water has a voltage difference that is so it is great that the dipole forces of the water do not separate the bitumen molecules from their respective ones Can bring rest positions, i.e. that the bitumen molecules are not aligned or be polarized. The oil that does not spread also fulfills the task, that in the bitumen to emulsify enclosed water (approx. 1 percent by weight), so this further Block water molecule migration path.

The amount of oil to be added depends on the type of bitumen and the type of bls. It varies between 0.1 to 2% parts by weight. The respectively added, Non-spreading oil can and will be with less addition, if it is bitumen and Require oil consistency, with well-known diluents, for example richloracethylene, benzene diluted in a known manner during the mixing process and evaporate again during short-term storage. A small remainder of the Solvent has no harmful effect.

To prevent water migration and the dissolution of bitumen Second, at the rock boundary, the bitumen molecules are passed through a molecular sieve mechanically stabilized in space, i.e. clays of montmorillionite, illite or kaolinite are in the compulsory mixer by adding water, with some clays better with lime liquor brought to honey plasticity and mixed with the bitumen in a high-performance mixer at a Initial temperature of about 100 ° C, which leads to the processing temperature of 140 to 200 ° C is increased, mixed.

This mixing process is a corresponding one with strong foaming Loss of water or water vapor accompanies and is upright for as long until the processing temperature for the respective bitumen (140- 2oo0C) no more foaming occurs.

The effect is: When the water in the clay mineral hydrate shell evaporates the clay minerals move away from each other and now offer the bitumen their wetting surfaces at.

The clay used must have the character of a molecular sieve, which is determined by the Space proportions of the bitumen and clay is determined. The determinable bitumen-clay ratio can be determined in the laboratory, as the clays are not pure and uniform in character to have.

This clay molecular sieve has the property of fixing molecules. The bitumen molecules this fixation removes the polarizability.

The remaining water content is also stabilized by the clay molecular sieve, i.e. in the form of a mono- or macro-molecular water layer on the clay minerals; the crystallization cavities cannot be created due to the fixation of the bitumen molecules Establish a connection with each other and thereby lose their effect as a water migration route.

Due to the changing behavior of bitumen, clay and rock material the bitumen-clay proportion is to be determined by the Marshall test, with the amount of the bitumen-clay mixture, the clay component due to its changing surface it can be determined that the mixture in the spreader bowl is not spreading.

To achieve the purpose of the invention, the bitumen molecules are summed up through the two-dimensional. Molecular sieve, represented here by a layer of iron oxide is mechanically stabilized.

For this purpose, a saturated iron formate solution (iron + iron acid) the acidic rock (e.g. quartzite chippings) during the drying process in the drying drum added by spraying. If the rock reaches the temperature above 1ooOC, the water in the solution evaporates and carbon dioxide escapes. if all the water as well as the vaporizable carbonic acid is broken down, the film is with the desired Mosieb surface and can come into contact with bitumen.

To save iron formate, the addition of Fe formate can also be used in the mixer when the aggregate in question is over the hot sieving was pulled out. The amount of heat required for evaporation is supplied to the rock of the water is necessary.

The effect of this treatment is that on the rock surface an Fe2 O3 film remains, which has a molecular sieve effect. The molecular sieve stabilizes the Bitumen mole cooler so that it is the hydrophilic or water-friendly ends of the bitumen molecules and the hydrophobic or water-hostile ends of the water migration path oppose and thus build up a water-repellent protective layer.

The bitumen layer as a film or paint can be used except in the case of acidic rock can also be used in sheet pile construction for steel sheet pile walls.

The amount of addition of the saturated iron formate solution depends on the size of the surface of the mineral (stored or freshly broken) and is included 1 - 3% wt .-% saturated solution. The surface of a rock for the Fe2 O3 film changes due to time and weather influences and the breaking process. Therefore varies the required iron formate solution between 1 - 3 aew

Claims (3)

Claims 1.) Process for the production of low-water and waterproof bitumen, bitumen bonds, layers, films and paints, characterized in that its molecules either by adding not Spreading, water-repellent oils electrostatically or by adding two-dimensional ones Molecular sieve forming substances, for example iron formate (Fe2 03) or through three-dimensional molecular sieve-forming substances, for example clays mechanically be stabilized. 2.) Manufacturing method according to claim 1, characterized in that that bitumen in the high-performance mixer with a non-spreading, water-repellent Oil, primarily silicone oil or paraffin oil, is mixed, which is at the test temperature still a moderate flow behavior and a higher evaporation temperature than the bitumen processing temperature from about 140 to 2000C. 3.) Manufacturing method according to claim 1, characterized in that that clays, for example Montmorilliontt, illite or kaolinite in the mixer with the addition of water brought to honey plasticity and bitumen in the so-called high-performance mixer Bitumen melting temperature of over 100 ° C is mixed and the mixture at a Treatment temperature of 140 / to 200 ° C is freed from the previously added water, 4.) Manufacturing method according to claim 1, characterized in that the rock during the mixing and drying process 1 to 3% of an iron and formic acid Iron formate solution is added by spraying.