HU212913B - Bitumen emulsion and process for using the bitumen emulsion and thickeners - Google Patents

Abstract

The present invention relates to a cationic bitumen emulsion comprising a bitumen, water, cationic emulsifier, thickener and optionally an additive. It is an object of the present invention to provide at least one nonionic, associative type thickener, generally in an amount of 0.05 to 1% by weight, based on the total weight of the bitumen emulsion. EN 212 913 B Description: 6 pages

Description

FIELD OF THE INVENTION The present invention relates to a bitumen emulsion containing a thickener, a process for the use of bitumen emulsion in road construction, roofing and dewatering, and a process for using a particular group of materials as a thickener in a bitumen emulsion.

During the production of cold-mixed asphalt from stone (rock chippings) and cationic bitumen emulsion, it is a common problem that bitumen is drained from the stones, so that only a very thin bituminous binder layer is formed on the stone surface. This difficulty is particularly troublesome when working with so-called open graded mixes, i.e. mixtures based on loosely graded aggregates. Thin bonding layers result in poor stability of the blend and the blend becomes wear-sensitive (aging-sensitive).

Many different methods have already been tried to solve this problem. Most often, smaller amounts of fine rock chippings are mixed into the bitumen emulsion to thicken the emulsion. However, this method has the disadvantage that the rock chips break the emulsion and result in a mixture which is extremely inelastic and therefore difficult to spread on the road.

Other methods of thickening the emulsion include additives such as carboxymethylcellulose, polyvinylpyrrolidone, methoxycellulose and the like. by thickening the aqueous phase (see, for example, U.S. Pat. No. 4,822,427, DE 3,934,856 and EP 403,005). However, all of these processes have the drawback that the additive absorbs water and / or has a negative effect on the breakage of the emulsion.

The most common thickeners used in bituminous acidic cationic emulsions are prerequisites for being nonionic or possibly cationic.

Another long-established method employs anionic emulsions, which emulsions can be prepared by selecting the emulsifiers with a very high viscosity (see, for example, Bacid Asphalt Emulsion Manual, Asphalt Institute Manual Series No. 19, 2nd Edition, page 6). The disadvantage of this type is that it breaks very slowly and is therefore not suitable for use in areas where there is a constant risk of rain (eg Sweden).

In the process of the present invention, we have developed a process using a type of thickener that interacts with the emulsifier on the surface of bituminous droplets, thereby creating a high pseudoviscosity network for the emulsion. However, the mesh is not so stable as to prevent the emulsion from forming a thick layer spread over the surface of the stone. The thickener belongs to the group commonly known as "associative thickeners". Such thickeners have the general structure "hydrophobic-hydrophilic-hydrophobic". Further information on this group of thickeners can be found, for example, in "Associativc Thickeners and Their Rheological Influence on Trade Sale Formulations", J.E. Glass et al., Org. Coat. Appl. Polym. Sci. Proc., 47, 498-502 (1982).

The cationic-type bitumen emulsion of the present invention containing a thickener is characterized in that the thickener comprises at least one material selected from the group of nonionic type associative thickeners.

In one form of the bitumen emulsions of the present invention, nonionic type associative thickeners are hydrophobically modified urethane ethoxylates, preferably urethane ethoxylates of formula (I),

SHE

II

RNC- (CH ₂ CH ₂ O) _X

I

H i ~ O o

II II

CNRNC- (CH ₂ CH ₂ O) II

Η H o

II

-C-N-R '

I H (I) in which

R and R 'each have the same or different C 12 -C 18 straight or branched alkyl group,

R is a saturated or unsaturated hydrocarbon chain having from 7 to 36 carbon atoms, a portion of which may form a ring when closed, x is 90-500 and n is 1, 2, 3 or 4.

The concentration of the thickener in the bitumen emulsion depends on the nature of the particular thickener used and on the properties of the particular bitumen emulsion. Generally, the concentration of the thickener is in the range 0.05 to 1% by weight of the bitumen emulsion. The typical concentration is preferably determined in each case by a single series of experiments in which the thickener is used in varying concentrations.

The bitumen emulsion of the present invention may be prepared by mixing thickeners and a standard cationic type bitumen emulsion according to conventional blending methods for bitumen products.

The standard cationic bitumen emulsions used as starting materials in the preparation of the bitumen emulsion of the present invention generally contain from 50 to 70% by weight of bitumen (starting material) based on the total weight of the emulsion.

The emulsifier used in the bitumen emulsions used as starting material in the preparation of the emulsions of the present invention has no critical role. Emulsifiers present in cationic bitumen emulsifiers include, for example, fatty acid diamines, quater

Ammonium compounds, ethoxylated amines, amidoamines and imidazolines.

In a preferred form of the bitumen emulsion of the present invention, the bitumen emulsion has an added breakage additive in the form of a water-in-oil emulsion in which the aqueous solution of a neutralizing agent is dispersed in an oil continuous phase.

The term "neutralizing agent" is used herein and in the claims to a material which, when added to a bitumen emulsion, has a neutralizing effect on the bitumen emulsion.

The neutralizing agents are preferably basic salts of organic bases, organic or inorganic acids, and alkali metal hydroxides which are soluble in water but sparingly soluble or insoluble in oil.

Examples of the above materials include low molecular weight amines from organic bases such as monoethanolamine, diethanolamine, triethanolamine and aminopropanol; basic salts of organic acids are trisodium citrate; basic salts of inorganic acids are sodium carbonate, sodium borate, sodium silicate and trisodium phosphate; and among the alkali metal hydroxides are sodium hydroxide and potassium hydroxide.

The neutralizing agent is preferably dispersed in a mineral oil or a petroleum naphtha solvent.

The emulsifying grains used to emulsify the neutralizing solution in the oil must be of the nonionic type and have an HLB (Hydrophilic-Lipophilic Ralance) in the range of 3-9, preferably 5-7.

The appropriate amounts and compositions of the breakage additive required for various purposes and effects can be readily determined by a series of experiments. However, the amount of said additive will generally be from 1 to 10% by weight, preferably from 1.5 to 6% by weight and particularly preferably from 2 to 4% by weight, based on the total weight of the final bitumen emulsion.

The present invention also relates to a process for the use of a non-ionic type associative thickener, wherein the material is used as a thickener in a cationic type bitumen emulsion.

The nonionic type associative thickener may be a hydrophobically modified methane ethoxylate, preferably a modified urethane ethoxylate of formula (I) wherein R, R 'and R, and x and n are as defined above.

A further aspect of the present invention is a process for applying the bitumen emulsion of the invention, wherein the bitumen emulsion is used in road construction, road maintenance or construction work such as roofing, coating and waterproofing.

In a preferred embodiment of this part of the invention, a water-in-oil oil-dispersed emulsion of an aqueous solution of a neutralizing agent is incorporated into the bitumen emulsion prior to or in connection with the use of the bitumen emulsion.

The following non-limiting illustrative examples serve to illustrate the invention in further detail.

Example 1

A. A distilled bitumen (industrial product, trade name BE60M [Nynas Bitumen AB, Johanneshov, Sweden]) containing an average fracture cationic bitumen emulsion containing 60% by weight of the total emulsion was filled into a mixing vessel. The hydrophobically modified urethane ethoxylate (Collacral PU 75 (BASF, Ludwigshafen, Federal Republic of Germany)), a hydrophobically modified compound of formula (I), was added to the bitumen emulsion.

The viscosity of the additive-containing emulsion was measured using a Brookfield viscometer equipped with a 4 spindle. The sample was tested at 5 rpm.

The additive was used in three different concentrations, 0.1, 0.2 and 0.4% by weight, based on the total weight of the emulsion. For comparison, the viscosity of the additive-free emulsion was also determined.

B. The procedure of step A was repeated, but another hydrophobically modified urethane ethoxylate of the formula I (Collacral PU 85 (BASF, Ludwigshafen, Federal Republic of Germany)) was used as an additive.

The results of the viscosity tests are shown in Table 1 below.

Example 2

The experiment described in Example 1 was repeated, but instead of the emulsion given in Example 1, a distilled bitumen (commercially available under the trade name BE60M (Nynas Bitumen AB, Johanneshov, Sweden)) had an average fracture of 67% by weight based on the total weight of the emulsion. A cationic type bitumen emulsion was used and the following hydrophobically modified urethane ethoxylates of the formula I were used as additives in varying amounts.

A. Collacral PU 75 [BASF, Ludwigshafen, Germany

Federal Republic];

B. Collacral PU 85 [BASF, Ludwigshafen, Germany

Federal Republic];

C. Acrysol RM 8 [Rohm & Haas, Philadelphia, USA];

D. Bermodol PUR2100 [From Nobel AB, Stockholm,

Sweden];

E. Collacral DS 6049 [BASF, Ludwigshafen, Germany

Federal Republic],

The results are shown in Table 1 below.

Example 3

The experiment described in Example 1 was repeated, but instead of the emulsion given in Example 1, one

HU 212,913 ument polymer modified bitumen (industrial product, commercially designated PME 89 [Nynas Bitumen AB, Johanneshov, Sweden]) was used as a fast-breaking, cationic-type bitumen emulsion containing 67% by weight of the total emulsion. The additives used in Example 1 were thus:

A. Collacral PU 75 [BASF, Ludwigshafen, Germany

Federal Republic];

B. Collacral PU 85 [BASF, Ludwigshafen, Germany

Federal Republic];

The results are shown in Table 1 below.

Example 4

The experiment described in Example 1 was repeated, but instead of the emulsion given in Example 1, a distilled bitumen (industrial product, trade name BE65R [Nynas Bitumen AB, Johanneshov, Sweden]) containing 67% by weight of the emulsion was fast broken. , a cationic type bitumen emulsion was used. The additives used in Example 1 were thus:

A. Collacral PU 75 [BASF, Ludwigshafen, Germany

Federal Republic];

B. Collacral PU 85 [BASF, Ludwigshafen, Germany

Federal Republic];

The results are shown in Table 1 below.

Table 1

Additive The emulsion has a viscosity of [Paxs] Conc. (lake- in%) Type 1 2 3 4 - - 0.6 1.6 0.6 1.8 0.05 THE 13.2 0.05 B 12.4 0.1 THE 2.6 14.4 8.0 4.0 0.1 B 2.8 14.8 10.4 5.2 0.2 THE 6.4 14.0 12.8 4.8 0.2 B 4.0 12.8 14.0 6.0 0.2 C 3.6 0.2 D 5.4 0.2 E 5.2 0.4 THE 4.8 15.4 12.0 4.8 0.4 B 6.8 17.2 16.8 6.0 0.4 C 8.4 0.4 D 17.2 0.4 E 23.8

Note on Additives (Examples 1-4)

A: Collacral PU 75

B: Collacral PU 85

C: Acrysol RM 8

D: Bermodol PUR 2100

E: Collacral DS 649

Example 5

Mixtures were prepared according to the procedure of Example 1, starting from the bitumen emulsion of Example 2 (BE65M [Nynas Bitumen AB. Johanneshov, Sweden]) and all additives of Example 2 (AE.) Based on the weight of the emulsion. , 2% by weight.

Mixtures were prepared using mineral aggregates and all bituminous emulsion containing additive containing 500 g aggregates moistened with 1% w / w water (used 0-16 mm Farsta granite corresponds to 0-16 mm stone hardened by Swedish Road Administration). requirements for asphalt emulsions (Road Administration, Sweden "Structural engineering directions and generic advices"}). 7% by weight of bitumen emulsion based on aggregate weight was added and the mixture was then poured into a funnel which had a filter at the bottom of the funnel for the Run off and Wash off tests. construction.

"Outflow" means the amount of material that accumulates within 30 minutes in a weighed aluminum sealing container placed under the funnel. The container was oven dried at 110 ° C. The amount of "leakage" is expressed as the percentage of binder loss per unit weight of aggregate.

The sample funnel remaining in the funnel is then used in the "release" test as described below.

After one hour, 200 mL of water was poured over the sample in the funnel and the eluate was collected in a weighed aluminum container. The contents of the container were dried in an oven at 110 ° C. The amount of "dissolution" is expressed as a percentage by weight of binder loss, similar to that described for "outflow". The procedure is described in "Basic Asphalt Fmulsion Manual", Asphalt, Institute, College Park, Maryland, USA.

The results of the above tests and the comparative study using the unadulterated emulsion are shown in Table 2 below.

Table 2

Additive "Outflow" (% by weight) “Wash” (wt%) Without additives 0.56 0.64 Collacral PU 75 - 0.40 Collacral PU 85 - 0.42 Acrysol RM8 0.04 0.82 Bermodol PUR 2100 0.17 0.55 Collacral DS 6049 0.30 0.59

HU 212 913 Β

The results show that the additives prevent or reduce the "leakage", but have no harmful effect on the breakage of the emulsions.

The results indicate that the use of an emulsion according to the invention makes it possible to use a higher concentration of bituminous binder in cold mixed asphalt and, consequently, it is possible to provide higher traffic volumes and longer life times than hitherto considered possible. Cold mixing processes may also be used in the production of asphalt for service.

Example 6

One distilled bitumen (industrial product, commercially available as BE 65 M [Nynás Bitumen AB, Johanneshov, Sweden]) for medium-breaking cationic bitumen emulsion containing 67% by weight of total emulsion - based on the weight of bitumen emulsion - 2.1 20% by weight of a breakdown additive and a hydrophilically modified urethane ethoxylate of the formula I (Collacral PU 75 (BASF, Ludwigshafen, Germany)). The breakage additive was in the form of a water-in-oil emulsion in which the oil phase contained 6.6% by weight of Hypermer A60 solution (industrial product, ICI Europe Ltd, Cortenberg, Belgium) and 0.33% by weight of Diamin BG ( industrial product, 30 Scanroad AB, Nacka, Sweden) and hydrogenated naphthenic oil (Nytex 800 standard grade) containing 0.66% by weight of Viscoplex BA9-700 (industrial product Rohm GmbH, Darmstadt, Germany) [Nynas Naphthenics AB, Nynás 35 hamn, Sweden)) and the aqueous phase consists of an aqueous solution containing 8% by weight of sodium carbonate and 16% by weight of trisodium citrate, and said water-in-oil emulsion contains a total of 70% by weight of water.

The mixture of the breaking additive and the thickener was mixed with a glass rod 40 just prior to the addition of 50 g of the emulsion to 500 g of a so-called loose-size mineral aggregate. The aggregate / emulsion mixture was mixed with a 45 steel spatula for 60 seconds and then poured into a plastic funnel fitted with a filter at the bottom of the funnel for performing "spill" and "wash out" tests.

In this case, there was no 'leakage' within 30 minutes. (A few drops of clear water were visible, but bitumen did not appear.)

After one hour, the mixture was also tested for "leaching" by adding 200 ml of water to the mixture.

Ο r O above. No "washout" (clear water from the funnel).

Example 7

The procedure of Example 1 was repeated, but using a slow breaking cationic bitumen emulsion at 66% based on the total weight of the emulsion; the trade name of the bitumen used is P92-21201, manufactured by Nynás Bitumen AB, Johanneshov, Sweden, instead of Example 1. The following associative type thickeners were used in varying amounts:

1. Atlas G1822, ICI Europe Ltd, Kortenberg, Belgium.

2. Atlas G1823, ICI Europe Ltd, Kortenberg, Belgium.

The chemical structure of both products is poly (ethylene glycol) 150 distearate.

The viscosity of the additive emulsions was measured with a Brookfield viscometer equipped with a 25 spindle. The samples were tested under the following conditions: speed: 6 rpm; temperature: 40 'C.

The results are summarized in Table 3 below.

Table 3

Additive type Additive amount Viscosity (MPa.s) Additive number 0 420 1 0.1 480 1 0.2 900 1 0.5 1800 2 0.1 780 2 0.2 880 2 0.5 2400

PATENT CLAIMS

Claims (11)

Claims 1. A cationic type bitumen emulsion comprising bitumen, water, a cationic emulsifier, a thickener and optionally refractory additives, characterized in that it contains at least one nonionic associative type thickener in an amount of 0.05 to 1% by weight based on the total weight of the bitumen emulsion. Bitumen emulsion according to claim 1, characterized in that the nonionic type associative thickeners are hydrophobically modified urethane ethoxylates. Bitumen emulsion according to claim 2, characterized in that the hydrophobically modified urethane ethoxylates are the urethane ethoxylates of the general formula (I), O - O RNC- (CH ₂ CH ₂ O) _X -C_N-RNC- (CH ₂ CH ₂ O) -C-N-R '(I) EN 212 913 Β of which R and R 'are each C 12 -C 18 alkyl, the same or different, linear or branched, R is a saturated or unsaturated hydrocarbon chain having from 7 to 36 carbon atoms, a portion of which may form a ring when closed, x is 90-500 and n is 1, 2, 3 or 4. 4. A bitumen emulsion according to any one of claims 1 to 4, characterized in that the bitumen emulsion comprises an added breakage additive in the form of a water-in-oil emulsion, in which the aqueous solution of a neutralizing agent is dispersed in an oil continuous phase. 5. Bitumen emulsion according to claim 4, characterized in that the neutralizing agent is selected from the group consisting of organic bases, organic O II RNC- (CH ₂ CH ₂ O) _X I H which formula R and R 'each have the same or different C 12 -C 18 straight or branched alkyl, R is a saturated or unsaturated hydrocarbon chain having from 7 to 36 carbon atoms, a portion of which may form a ring when closed, x is 90-500 and n is 1, 2, 3 or 4. Bitumen emulsion according to claim 4 or 5, characterized in that the neutralizing agent is preferably dispersed in a mineral oil or in a petroleum naphtha-type solvent. 7. A method of using a nonionic type associative bleaching agent, wherein the cationic type bitumen emulsion is used as a thickening agent in an amount of at least 0.05% by weight. The process of claim 7, wherein the nonionic type associative thickener is a hydrofluorically modified urethane ethoxylate. The process according to claim 8, wherein the hydrophobically modified urethane ethoxylates are the urethane ethoxylates of formula (I), O II -C-N-R '(I) I η H for use in bitumen emulsion, characterized in that bitumen emulsion is used in road construction, road maintenance and construction work. 10. Procedure 1-3. Basic salts of inorganic or acidic acids according to any one of claims 1 to 3 and alkali metal hydroxides which are soluble in water but sparingly soluble or insoluble in oil. 5 11. A process according to claim 10, characterized in that the water-in-oil dispersed emulsion of the aqueous solution of the neutralizing agent, known per se, is mixed with the bitumen emulsion prior to or in connection with the application of the bitumen emulsion. rO O II II -CNRNC- (CH ₂ CH ₂ O) II Η H