CS207641B2 - Aqueous emulsion of the bitumen and rubber and method of making the same - Google Patents

Abstract

An aqueous bitumen and rubber emulsion is described which comprises a bituminous compound, a block copolymer with radial configuration of conjugated diene and aromatic vinyl compound and an emulsifier consisting of an amine salt and water. The process for the preparation of these aqueous bitumen and rubber emulsions consists in mixing a bituminous compound with a block copolymer with radial configuration of conjugated diene and aromatic vinyl compound, in introducing a proportion of the total quantity of amine into this mixture and in emulsifying this mixture in an aqueous phase containing the remainder of the quantity of amine as well as an acid in a quantity which is at least sufficient to neutralise all the amine. This emulsion can be employed in the field of road surfacing and roofing.

Description

The invention relates to aqueous bitumen emulsions and an improved process for the manufacture of rubber-containing aqueous bitumen emulsions.

Biturnin mixtures containing a bituminous compound and a rubber, which is most often a block copolymer of conjugated dienes are. (C 4 -C 12) atoms; aromatic vinyl compounds have numerous uses, for example as road coatings, as glue or as roofing.

If these bituminous mixtures were to be used on pavements, large amounts of solvent had to be added to them to reduce them. viscosity of the composition, thereby facilitating its application. on the road. However, this method of use has many disadvantages, in particular the need to evaporate large quantities. and the need to wait a relatively long time before the road could be opened for traffic.

The first improvement was achieved by preparing aqueous emulsions of bitumen and rubber. The process consists in admixing bitumen with rubber, most often a block copolymer of conjugated diene and aromatic vinyl compound, and this mixture is emulsified with water containing an emulsifier and an acid. However, it has been found that it is difficult to emulsify the entire bitumen-rubber mixture at temperatures usually used. 2 .......

between 120 and 140 ° C. · Usually no more than can be cured. 40% bitumen mixture with rubber.

The invention. aims to overcome these disadvantages and its object is an aqueous emulsion consisting of a mixture of bitumen, rubber and an emulsifier. Its. The subject of the invention is further an improved process for the production of aqueous bitumen and rubber emulsions enabling the entire bitumen / rubber mixture to be emulsified.

It has now been found that when using a polystyrene-polybutadiene block copolymer of radial configuration, aqueous bitumen and rubber emulsions with very small micelles are obtained.

Aqueous bitumen emulsion a. The rubber according to the invention is characterized in that it contains from 25 to 25%. 55 wt. %, preferably 30 to 30%. 40% by weight based on the weight of the emulsion, water, 0.05 to 2% by weight, preferably 0.1 to 1.5% by weight, based on the weight of the emulsion, of an aliphatic or alicyclic amine salt containing at least 10% by weight carbon atoms as an emulsifier, the remainder being a mixture of bitumen with a penetration of between 10 and 300 and a softening point of between 25 and 95 ° C and a block copolymer of polybutadiene and polystyrene of radial configuration and molecular weight between 50,000 and 300,000, % of the copolymer in the mixture is 2 to 20% by weight, preferably 4 to 15% by weight.

As bitumen, which is a major component of the aqueous emulsions of the invention, natural bitumen or bitumen obtained directly as a residue from. Distillation of crude oil or oxidized bitumen. In particular, bitumen is characterized by its penetration, i.e. the penetration depth of a standardized needle, subjected to a load of 100 g within 5 s at 25 ° C into bitumen, the penetration being measured in tenths of a millimeter (ASTM-D-551). Another characteristic of bitumen is the softening temperature measured by the Ring and Pack method (ASTM-D-3626).

The radial configuration butadiene-styrene block copolymer used in the emulsion of the invention is prepared by copolymerizing butadiene and styrene in the presence of an organolithium initiator. The obtained block copolymer contains an active lithium atom at one end of the polymer chain.

Then, a block copolymer whose chain is terminated with one active lithium atom is reacted with a polyfunctional compound having at least 3 reactive sites capable of reacting with a carbon-lithium bond and attached to the carbon atom having that bond. A branched copolymer of this type is obtained whose individual branches originate from a polyfunctional compound core. This creates a radial structure of the following

One 'method of preparing' such a radial-type copolymer is described in U.S. Pat. No. 3,281,383. These radial-type block copolymers contain amounts of butadiene and styrene relative to each other, which can vary within wide limits. Usually the amount is butadiene. 50 to 70% by weight and 50 to 30% by weight of styrene. Molecular weight. These copolymers may range between 50,000 and 300,000, and preferably between 75,000 and 250,000.

The emulsifiers used in the emulsions of the invention are cationic. emulsifiers prepared by neutralization. a straight or branched aliphatic amine; a cyclic amine (monoamine, diamine, polyamine or mixtures thereof) containing at least 100 carbon atoms, with an organic or inorganic acid, for example acetic acid, hydrochloric acid, sulfuric acid, phosphoric acid. This reaction takes place directly in the emulsion medium. Examples of amines are:. in particular, a tallow diamine in which the alkyl chain contains 16 to 18 carbon atoms, an amidoamine resin acid and an imidazoline resin acid. Choice. Acids depend in particular on the 'availability,' cost and technological conditions. Of course, acids readily available, cheap and low volatile are used. For these reasons, the acid usually used to carry out the reaction is hydrochloric acid.

The amount of emulsifier used to prepare the aqueous emulsions of the invention may vary within wide limits. Usually, however, it is used as small as possible. an amount to obtain stable emulsions.

Too large amounts of emulsifier retard emulsion breakdown. 'after her. use on site.

The process for the preparation of the aqueous bitumen-rubber emulsions of the invention is characterized in that the bituminous compound is mixed with a conjugated diene block copolymer and an aromatic vinyl compound block copolymer. In the radial configuration, part of the total amine is added to the mixture and the mixture is 'emulsified' in the aqueous phase containing the remaining amount of amine as well as the acid in at least an amount sufficient to neutralize the entire amount of amine.

One feature of the process of the present invention for the production of aqueous bitumen-rubber emulsions is that 40-70% of the total amount of amine used is added to the bitumen-rubber mixture, the remainder being added with the acid to the aqueous phase. . If the total 'amount of amine' is added either to the bitumen-rubber mixture or to the 'aqueous' phase, the total' amount of the 'bitumen-rubber mixture' will not be agglomerated.

Another feature of the process of the invention is the high viscosity of the bitumen / rubber mixtures which can be emulsified without the aid of a solvent. . It is known, . The addition of a block copolymer bitumen considerably increases the viscosity of the bitumen. The viscosity of the bitumen / rubber mixture to be emulsified must normally be less than 0.4 Pa. at the emulsion preparation temperature, if no solvent is required. The process according to the invention makes it possible to emulsify. a mixture of bitumen and block 'copolymers having a radial configuration with a viscosity of up to 5 Pa. at an emulsion preparation temperature of generally 140-190 ° C without the use of a volatile solvent.

The amounts of water to be used will be such that the 'aqueous emulsion' has a viscosity allowing easy handling at the temperature of use. However, this viscosity must be high enough that the emulsion does not flow from where it has been applied. Usually an amount of water corresponding to 25 to 55% by weight, and in particular 30 to 40% by weight, based on the total weight of the emulsion, is used.

Aqueous phase. contains. also a certain amount - an acid which is at least equal to the amount required for neutralization of the amino compound contained. in a mixture of bitumen and rubber and in an aqueous phase. It is very important for the stability of the aqueous emulsion that this amount of acid is sufficient. The diffusion of the amyl compound from the micelles outwards proceeds very slowly and may take several days. If the amount of acid added is not sufficient, the emulsion,. which appears to be stable at the time of preparation, destabilizes in a few days by the appearance of amino compounds that are no longer neutralized. Typically, an amount of acid corresponding to 1.2 to 2 times the amount stoichiometrically required to neutralize the added amino compound is used.

In particular, the mean micelle size as well as the sedimentation coefficient were determined in the following exemplary embodiments, which data make it possible to assess the storage stability of the bitumen emulsions and the emulsion breakdown rate. Bituminous emulsion rate. the greater the smaller the burst index, measured by the number. grams of SiO 2 to be added to 100 g of emulsion to break it. This burst rate must be neither too low (unstable emulsion) nor too high (too stable emulsion). Usually - the index - is admitted. between 25 and - 100 · g SiO2 per. 100 g emulsion. The rate of bursting can also be measured by the bursting time of the emulsion applied to the road. This time also depends on atmospheric conditions. It is usually 20 minutes to 90 minutes. Density is given in g / cm3.

P ^^ asked ·

It mixes. bitumen having a penetration of approximately 200 and a softening temperature of 42 ° C; a block copolymer of polystyrene and polybutadiene. the radial configuration having a molecular weight of 250,000. The amount of block copolymer is 6% by weight of the total. Time. the incorporation of rubber into bitumen is 2. hours 30 minutes.

To this mixture is added 0.3% by weight (calculated on the weight of bitumen and rubber-tallow diamine) and 0.075% (calculated on the weight of bitumen and rubber) of the tallow polyamine. · The viscosity of this mixture measured with a Brookfield viscometer at 175 ° C is 1.5 Pa.

This mixture is granulated by being introduced at atmospheric pressure and 175 DEG C. into an aqueous phase Hurrel-type colloid mill containing, in addition to water, 0.3% by weight of tallow diamine, 0.075 ·% by weight of tallow polyamine and 1% by weight of tallow polyamine. % By weight, of hydrochloric acid having a density of 1.19, the percentages being calculated on the weight of water. The aqueous phase has a temperature of 60 ° C. The weight ratio between the bituminous mixture and the aqueous phase is 66 to 34.

The emulsion - the whole bitumen mixture - with the rubber and the emulsion obtained - has the following properties:

- medium - micelle size: 3 to 5 μπι - sedimentation coefficient (AST.M-D-244-75): 3 «/ o - thawing index: 35 g SiO2 per

100 g emulsion - break - on - road: 30 minutes

For comparison, the same mixture of bitumen and block copolymer was prepared in a radial configuration, but without the addition of an emulsifier. - This mixture was emulsified by being introduced under atmospheric pressure and at 175 ° C into a colloid mill - with an aqueous phase - containing - 0.88% by weight of tallow diamine, - 0.23% by weight of polyamine from - tallow and 1.2 why. % by weight, of hydrochloric acid having a density of 1.19, these percentages being calculated on the weight of water. - aqueous phase has a temperature of 60 ^{Э С} and the weight ratio between the bituminous -Mixtures - - and - aqueous phase - is - 66 - to - 34 Zemulgovalo only 70% - bituminous mixtures.

In another comparative example, the same mixture of bitumen and block copolymer - of the - radial configuration - was prepared and added to it - 0.45% by weight, (calculated on the weight of bitumen and rubber) of the tallow and 0, 12% by weight of the tallow polyamine (calculated on the mixture of bitumen and rubber) of the tallow, which was emulsified by introducing - at atmospheric pressure and at a temperature of - 175 ° C, to a water-cooled colloid mill. - phase - - containing only 1,2 ° / o - by weight, - calculated - per - by weight of the aqueous phase, hydrochloric acid - - at - density - 1,19 The aqueous - phase - had a temperature of - 60 ° C and by weight the ratio - between the bituminous mixture and the - aqueous phase was - 66 - to 34. Only 40% of the - bituminous - mixture were emulsified.

A - d - 2

The bitumen having a penetration of approximately 180 and a softening temperature of 42 ° C is admixed with a block copolymer of polystyrene and polybutadiene having a radial configuration and a molecular weight of 250,000. The amount of block polymer is 7% by weight, - total quantity. The incorporation time of the rubber into bitumen is ~ 3 hours. 0.4% by weight, based on the weight of bitumen and copolymer, of tallow diamine and 0.1 why are added to this mixture. % by weight (based on the weight of bitumen and copolymer) of tallow polyamine.

The viscosity of this mixture, measured with a Brookfield viscometer at 145 ° C, was 1.5 Pa. with.

This mixture is granulated by being introduced at atmospheric pressure and a temperature of Í45 ° C into a Hurrell-type colloidal mill with an aqueous phase containing, in addition to water - 0.4% by weight, tallow diamine, 0.1% by weight, tallow polyamine and 2% by weight, hydrochloric acid having a density of 1.19, the percentages being calculated on the weight of water. The aqueous phase is at 60 ° C. The weight ratio between the bituminous mixture and the aqueous phase is 70 to 30.

The whole bitumen / rubber mixture is emulsified and the emulsion obtained has the following properties:

- mean micelle size: 15 to 35 μΐη - sedimentation coefficient (ASTM-D-244-75):

% - Decomposition index: 90 g SiO2 per 100 g emulsion

Example 1 a d 3

The procedure described in Example 1 was repeated, but using. 1.9% by weight, calculated on the weight of water, of 85% acid solution. phosphorous. instead of hydrochloric acid. .

The whole bituminous mixture is emulsified and the emulsion obtained has the following properties:

- mean micelle size: 4 to 7 μπι - sedimentation coefficient (ASTM-D-244-75):

% W / w index of thawing: 35 g of S1O2 per 100 g of emulsion

Example 4

A bitumen of about 30 penetration is mixed with. . a block copolymer of polystyrene and polybutadiene having a radial configuration having a molecular weight of 150,000. The amount of block polymer represents 5% by weight of the total amount. . The incorporation time of the rubber into bitumen is 2 hours.

0.4% by weight of the mixture is added to the mixture. weight of bitumen and copolymer, amidoamine resin acid.

Viscosity of this mixture measured by Brookfield. viscosimeter at 175 ° C is 1.75 Pa. with.

This mixture is granulated by being introduced at atmospheric pressure and at 175 DEG C. into an Hurrell-type water-based colloid mill containing, in addition to water, 0.4% by weight of water of the same emulsifier and .0.8. % by weight, based on the weight of water, of hydrochloric acid having a density of 1.19. The aqueous phase has. temperature 60 ° C. The weight ratio between the bituminous mixture and the fragrance phase is 66 to 34. The mixture is emulsified. the whole bituminous mixture and. the emulsion obtained has the following characteristics:

- mean micelle size: 3 to 5 μΐη - sedimentation coefficient (ASTM-D-244-75):

% - Decomposition index: 40 g S1O2 per 100 g emulsion

Example 1 a d 5

The procedure of Example 1 is followed, but 0.4% by weight of tallow diamine is added to the bituminous mixture.

The viscosity of this mixture as measured by a Brookfield viscometer at 175 ° C is 1.5 Pa. with.

This mixture. It is granulated by being introduced into the colloidal at atmospheric pressure and 175 ° C. water-phase Charlotte mills containing, in addition to water, 0.4% by weight of water, tallow diamine and 1.2% by weight of water of 1.19 g / l of hydrochloric acid The aqueous phase is at a temperature of 60 DEG C. The weight fraction between the bituminous mixture and the aqueous phase is 68 to 32 cm @ ³ .

He's culling. the whole bituminous mixture and the obtained emulsion have the following properties:

- mean micelle size: 4 to 6 μΐη - sedimentation coefficient (ASTM-D-244-75):

% - Thawing index: 33 g S1O2 per 100 g emulsion

For comparison, the same experiment was repeated under the same operating conditions, but a polystyrene-polybutadiene-polystyrene-type linear block copolymer was used, wherein the molecular weight of the polystyrene blocks was 14,000 and the molecular weight of the polybutadlene block was 65,000.

The total mixture of bituminous a. the emulsion had these. Properties:

- average micelle size: 20-30 .mu.m, but the presence of particles having a size between 200 and 500 .mu.m.

- sedimentation coefficient (ASTM-D-244-75):

- thawing index: 30 g S1O2 per 100 g emulsion

She said d6

Bitumen with a penetration of approximately 180 was mixed with the block. copolymer of polystyrene 'and polybutadiene of radial'. . a configuration having a molecular weight of 150,000. % of the total polymer. The time of incorporation of the copolymer into bitumen was 3 hours.

0.4% by weight, based on the weight of bitumen and copolymer, of tallow diamine and 0.4% by weight, based on the weight of bitumen and copolymer, of tallow polyamine are added to this mixture.

The viscosity of this mixture as measured by a Brookfield viscometer at 190 ° C is 4.5 Pa. . with.

This mixture is emulsified by adding it at atmospheric pressure. pressure and 190 ° C to a Hurrell-type colloid mill with an aqueous phase containing, in addition to water, 0.4% by weight, tallow diamine, 0.4. % by weight of tallow polyamine and 2.0% by weight of hydrochloric acid having a density of 1.19, based on the weight of water. The aqueous phase has a temperature of 60 ° C. The weight ratio between the bituminous mixture and the aqueous phase is 60 to 40.

The total bituminous mixture was emulsified and the emulsion obtained had the following properties:

- medium micelle size: approximately 80% micelles between 5 and 10 ди approximately 20% micelles between 30 and 50 μΐη - sedimentation coefficient: 40% - burst index: 90 g S1O2 per 100 g emulsion

Claims (9)

Subject An aqueous bitumen-rubber emulsion comprising 25 to 55% by weight, preferably 30 to 40% by weight, based on the weight of the emulsion, water, 0.05 to 2% by weight, preferably 0, 1 to 1.5% by weight, based on the weight of the emulsion, of an aliphatic or alicyclic amine salt containing at least 10 carbon atoms as an emulsifier, the remainder being a mixture of bitumen having a penetration of between 10 and 300 and a softening point of between 25 and 95 And a block copolymer of polybutadiene and polystyrene having a radial configuration and a molecular weight of between 50,000 and 300,000, the amount of block copolymer in the mixture being 2 to 20% by weight, preferably 4 to 15% by weight. Aqueous emulsion according to Claim 1, characterized in that it comprises natural bitumen as bitumen, bitumen obtained directly as the crude oil distillation residue or oxidized bitumen. Void emulsion according to Claim 1, characterized in that the amine used is monoamine, diamine, polyamine or mixtures thereof, and in particular of tallow diamine, tallow polyamine, resin acid amidoamine and resin acid imidazoline. 4. A process for the production of an aqueous bitumen-rubber emulsion as claimed in any one of claims 1 to 3, wherein the bitumen is mixed with a block copolymer of conjugated diene and aromatic vinyl compound with radial inventive figuration, to which a portion of the total amine is added. this mixture is emulsified in an aqueous phase containing the remaining amount of amine as well as the acid in at least an amount sufficient to neutralize the total amount of amine. Process according to claim 4, characterized in that the emulsifier is used in an amount of 0.05 to 2% by weight, preferably 0.1 to 1.5% by weight, based on the weight of the emulsion. 6. A process according to claim 4, wherein 40 to 70% by weight of the total amount of amine used and the remaining amount of amine are added to the aqueous phase to the mixture of bitumen and block copolymer of radial configuration. 7. The process of claims 4 to 6 wherein the emulsion is prepared at a temperature in the range of 140-190 [deg.] C. . 8. A process according to any one of claims 4 to 7, wherein the viscosity of the mixture of bitumen and block copolymer of radial configuration is 1 to 5 Pa. s, preferably 1 to 2 Pa. at the emulsion preparation temperature. 9. A process according to any one of Claims 4 to 8 wherein the acid is added to the aqueous phase in an amount of 1.2-2 times the stoichiometric amount required to neutralize the amine that has been added to both the radial configuration bitumen and block copolymer mixture. phase.